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  1. Article: Comparison of the effects of high and low milk-replacer feeding regimens on health and growth of crossbred dairy heifers

    Johnson, K. F / Nair, R. Vinod / Wathes, D. C

    Animal production science. 2019, v. 59, no. 9

    2019  

    Abstract: Context Pre-weaning growth in dairy heifers is highly dependent on the amount of milk fed. Both milk replacer (MR) and associated labour are costly, encouraging restricted milk rations and once-a-day feeding. Aims This study compared performance relating ...

    Abstract Context Pre-weaning growth in dairy heifers is highly dependent on the amount of milk fed. Both milk replacer (MR) and associated labour are costly, encouraging restricted milk rations and once-a-day feeding. Aims This study compared performance relating to the growth and health of calves receiving one of two commercial feeding regimens: High or Low. Methods All heifers born during the Spring (January–March) calving block on a commercial UK farm with mixed-breed genetics were recruited at birth, randomly assigned to the High (n = 104, receiving MR-A) or Low (n = 88, receiving MR-B) feed group and reared indoors on straw bedding, with free access to concentrate. Both groups initially received MR twice daily. The High group continued to receive MR twice daily throughout the experiment, whereas the Low group calves were reduced to a single MR feed daily during Weeks 4–8. Blood samples were taken in Weeks 1 and 6 to assess passive transfer and measure circulating insulin-like growth factor 1 (IGF1). The Wisconsin calf-scoring system was used to assess health of calves in Weeks 1, 2, 4, 6 and 8 and at 6 months and size was also measured at these times. Data were analysed by univariate and multivariate models. Key results Passive transfer was good in both groups (serum total protein (mean ± s.d.) 60.9 ± 9.1 mg/mL) with no differences in pre-weaning disease incidence; diarrhoea occurred in 64.5% and bovine respiratory disease in 26.3% of calves. High group calves were significantly heavier, taller and longer at all pre-weaning examinations except recruitment owing to more growth in the first month, and remained significantly larger at 6 months: weight 157 ± 8 vs 149 ± 7 kg, height 103 ± 5 vs 100 ± 5 cm, length 90 ± 4 vs 88 ± 5 cm. Plasma IGF1 concentrations at around Week 6 were doubled in the High group (101 ± 38.6 vs 55 ± 34.1 ng/mL). Bovine respiratory disease was associated with reduced weight gain. Heifers with diarrhoea were leaner at weaning. High feed group, weight at recruitment and good passive transfer were positively associated with weight at 6 months. Conclusions Higher feeding levels pre-weaning increased growth rates and IGF1, although the disease incidence was unaffected. Implications Previous studies have shown that more growth and higher IGF1 pre-weaning are associated with a lower age at first calving and an increased chance of reaching the end of first lactation. These in turn improve long-term performance.
    Keywords blood proteins ; blood sampling ; bovine respiratory disease ; calf feeding ; calves ; calving ; crossbreds ; dairy heifers ; diarrhea ; disease incidence ; farms ; feeding level ; insulin-like growth factor I ; lactation ; milk ; milk replacer ; mixed breeds ; multivariate analysis ; rearing ; straw ; weaning ; weight gain ; United Kingdom
    Language English
    Size p. 1648-1659.
    Publishing place CSIRO Publishing
    Document type Article
    ZDB-ID 2472524-9
    ISSN 1836-5787 ; 1836-0939
    ISSN (online) 1836-5787
    ISSN 1836-0939
    DOI 10.1071/AN18432
    Database NAL-Catalogue (AGRICOLA)

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  2. Article ; Online: Analysis of pre-weaning feeding policies and other risk factors influencing growth rates in calves on 11 commercial dairy farms.

    Johnson, K F / Chancellor, N / Burn, C C / Wathes, D C

    Animal : an international journal of animal bioscience

    2017  Volume 12, Issue 7, Page(s) 1413–1423

    Abstract: Growth rates in pre-weaned calves influence their health, age at first calving and lifetime productivity. Many farms restrict milk rations to encourage solid feed intake and facilitate early weaning, but this can compromise growth. This study determined ... ...

    Abstract Growth rates in pre-weaned calves influence their health, age at first calving and lifetime productivity. Many farms restrict milk rations to encourage solid feed intake and facilitate early weaning, but this can compromise growth. This study determined the milk feeding policies and associated growth rates on 11 commercial dairy farms in South East England, each following their normal management regime. Between 26 and 54 heifers were recruited per farm, providing a final cohort of 492, of which 71% were pure Holstein. Information on calf rearing practices (feeding, weaning, housing) and health was collected via questionnaires and weekly observations. Estimates of actual milk fed (kg solids) between 1 and 63 days were calculated for individual calves. Morphometric data (weight, height, length) were taken at weeks 1, 5 and 9 and at a median age of 7.5 months and growth rates were calculated. Most calves were fed milk replacer via automated feeders (four farms), teat feeder (one) or buckets (four) whereas two farms provided drums of acidified waste milk. Farms fed between 4 and 6 l/day of milk at mixing rates of 10% to 15%, providing 400 to 900 g/day of milk solids. Both skeletal growth rates and average daily weight gain (ADG) increased in the second month of life compared with the first: height growth from 0.17±0.14 to 0.25±0.16 cm/day and ADG from 0.48±0.25 to 0.71±0.28 kg/day. Post-weaning heifers up to 7.5 months had height increases of 0.16±0.035 cm/day and ADG of 0.83±0.16 kg/day. From 1 to 63 days 70% of calves had growth rates <0.7 kg/day and of these 19.6% gained <0.5 kg/day. Mean ADG before 9 weeks varied between farms from 0.52±0.30 to 0.75±0.20 kg/day. This was related to the amount of milk fed at both a farm and individual calf level. Increasing the total milk solids fed between 1 and 63 days from 20.4 to 46.3 kg (the 10th to 90th percentile observed) was associated with an increase of 0.11 kg/day ADG. All farms had a wide variation in growth rates despite single feeding policies. Higher circulating immunoglobulin G and IGF1 concentrations were associated with better growth, whereas low temperatures in month of birth, high scores for diarrhoea, respiratory and umbilical disease and large birth size reduced growth. Many commercially grown dairy heifers therefore experienced growth restriction in the pre-weaned period, potentially reducing their health, welfare and productivity.
    MeSH term(s) Animal Feed ; Animals ; Cattle/growth & development ; England ; Farms ; Female ; Milk ; Risk Factors ; Weaning
    Language English
    Publishing date 2017-11-23
    Publishing country England
    Document type Journal Article
    ZDB-ID 2257920-5
    ISSN 1751-732X ; 1751-7311
    ISSN (online) 1751-732X
    ISSN 1751-7311
    DOI 10.1017/S1751731117003160
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Analysis of pre-weaning feeding policies and other risk factors influencing growth rates in calves on 11 commercial dairy farms

    Johnson, K. F / Burn, C. C / Chancellor, N / Wathes, D. C

    Animal. 2018 July, v. 12, no. 7

    2018  

    Abstract: Growth rates in pre-weaned calves influence their health, age at first calving and lifetime productivity. Many farms restrict milk rations to encourage solid feed intake and facilitate early weaning, but this can compromise growth. This study determined ... ...

    Abstract Growth rates in pre-weaned calves influence their health, age at first calving and lifetime productivity. Many farms restrict milk rations to encourage solid feed intake and facilitate early weaning, but this can compromise growth. This study determined the milk feeding policies and associated growth rates on 11 commercial dairy farms in South East England, each following their normal management regime. Between 26 and 54 heifers were recruited per farm, providing a final cohort of 492, of which 71% were pure Holstein. Information on calf rearing practices (feeding, weaning, housing) and health was collected via questionnaires and weekly observations. Estimates of actual milk fed (kg solids) between 1 and 63 days were calculated for individual calves. Morphometric data (weight, height, length) were taken at weeks 1, 5 and 9 and at a median age of 7.5 months and growth rates were calculated. Most calves were fed milk replacer via automated feeders (four farms), teat feeder (one) or buckets (four) whereas two farms provided drums of acidified waste milk. Farms fed between 4 and 6 l/day of milk at mixing rates of 10% to 15%, providing 400 to 900 g/day of milk solids. Both skeletal growth rates and average daily weight gain (ADG) increased in the second month of life compared with the first: height growth from 0.17±0.14 to 0.25±0.16 cm/day and ADG from 0.48±0.25 to 0.71±0.28 kg/day. Post-weaning heifers up to 7.5 months had height increases of 0.16±0.035 cm/day and ADG of 0.83±0.16 kg/day. From 1 to 63 days 70% of calves had growth rates <0.7 kg/day and of these 19.6% gained <0.5 kg/day. Mean ADG before 9 weeks varied between farms from 0.52±0.30 to 0.75±0.20 kg/day. This was related to the amount of milk fed at both a farm and individual calf level. Increasing the total milk solids fed between 1 and 63 days from 20.4 to 46.3 kg (the 10th to 90th percentile observed) was associated with an increase of 0.11 kg/day ADG. All farms had a wide variation in growth rates despite single feeding policies. Higher circulating immunoglobulin G and IGF1 concentrations were associated with better growth, whereas low temperatures in month of birth, high scores for diarrhoea, respiratory and umbilical disease and large birth size reduced growth. Many commercially grown dairy heifers therefore experienced growth restriction in the pre-weaned period, potentially reducing their health, welfare and productivity.
    Keywords automated feeders ; birth weight ; buckets ; calves ; calving ; dairy farming ; dairy heifers ; diarrhea ; early weaning ; farms ; feed intake ; Holstein ; immunoglobulin G ; issues and policy ; milk ; milk replacer ; mixing ; morphometry ; questionnaires ; rearing ; risk factors ; temperature ; wastes ; weight gain ; England
    Language English
    Dates of publication 2018-07
    Size p. 1413-1423.
    Publishing place Cambridge University Press
    Document type Article
    ZDB-ID 2257920-5
    ISSN 1751-732X ; 1751-7311
    ISSN (online) 1751-732X
    ISSN 1751-7311
    DOI 10.1017/S1751731117003160
    Database NAL-Catalogue (AGRICOLA)

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  4. Article: Synthesis of oligosaccharides by bacterial enzymes.

    Johnson, K F

    Glycoconjugate journal

    1999  Volume 16, Issue 2, Page(s) 141–146

    Abstract: Many human pathogens initiate disease by utilizing their microbial adhesin proteins to attach to glycoconjugates on host cell mucosal surfaces. Soluble oligosaccharides of identical or similar structure to these naturally occurring ligands can both ... ...

    Abstract Many human pathogens initiate disease by utilizing their microbial adhesin proteins to attach to glycoconjugates on host cell mucosal surfaces. Soluble oligosaccharides of identical or similar structure to these naturally occurring ligands can both prevent bacterial attachment as well as mediate the release of attached bacteria. Since it has not been possible to isolate large quantities of these compounds, we have developed enzyme-based technologies to synthesize several relevant human oligosaccharides. Using cloned bacterial glycosyltransferases, we can synthesize several hundred grams of these oligosaccharides at a time. The availability of these large quantities will allow these compounds to be tested as anti-adhesive pharmaceutical agents as well as lead to expanded practical applications.
    MeSH term(s) Bacteria/enzymology ; Bacteria/genetics ; Biotechnology ; Carbohydrate Sequence ; Gene Expression ; Genetic Vectors ; Globosides/biosynthesis ; Glycosyltransferases/biosynthesis ; Glycosyltransferases/metabolism ; Humans ; Molecular Sequence Data ; Oligosaccharides/biosynthesis ; Recombinant Proteins/biosynthesis ; Recombinant Proteins/metabolism ; Trisaccharides/biosynthesis
    Chemical Substances Globosides ; Oligosaccharides ; Recombinant Proteins ; Trisaccharides ; globotriose (66580-68-5) ; globotetraose (75660-79-6) ; Glycosyltransferases (EC 2.4.-)
    Language English
    Publishing date 1999-02
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 283770-5
    ISSN 1573-4986 ; 0282-0080
    ISSN (online) 1573-4986
    ISSN 0282-0080
    DOI 10.1023/a:1026440509859
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Heifer fertility and carry over consequences for life time production in dairy and beef cattle

    Wathes, D. C / Cooke, J. S / Johnson, K. F / Pollott, G. E / Richardson, H

    Animal. 2014 May, v. 8, no. s1

    2014  

    Abstract: The rearing period has a key influence on the later performance of cattle, affecting future fertility and longevity. Producers usually aim to breed replacement heifers by 15 months to calve at 24 months. An age at first calving (AFC) close to 2 years (23 ...

    Abstract The rearing period has a key influence on the later performance of cattle, affecting future fertility and longevity. Producers usually aim to breed replacement heifers by 15 months to calve at 24 months. An age at first calving (AFC) close to 2 years (23 to 25 months) is optimum for economic performance as it minimises the non-productive period and maintains a seasonal calving pattern. This is rarely achieved in either dairy or beef herds, with average AFC for dairy herds usually between 26 and 30 months. Maintaining a low AFC requires good heifer management with adequate growth to ensure an appropriate BW and frame size at calving. Puberty should occur at least 6 weeks before the target breeding age to enable animals to undergo oestrous cycles before mating. Cattle reach puberty at a fairly consistent, but breed-dependent, proportion of mature BW. Heifer fertility is a critical component of AFC. In US Holsteins the conception rate peaked at 57% at 15 to 16 months, declining in older heifers. Wide variations in growth rates on the same farm often lead to some animals having delayed first breeding and/or conception. Oestrous synchronisation regimes and sexed semen can both be used but unless heifers have been previously well-managed the success rates may be unacceptably low. Altering the nutritional input above or below those needed for maintenance at any stage from birth to first calving clearly alters the average daily gain (ADG) in weight. In general an ADG of around 0.75 kg/day seems optimal for dairy heifers, with lower rates delaying puberty and AFC. There is some scope to vary ADG at different ages providing animals reach an adequate size by calving. Major periods of nutritional deficiency and/or severe calfhood disease will, however, compromise development with long-term adverse consequences. Infectious disease can also cause pregnancy loss/abortion. First lactation milk yield may be slightly lower in younger calving cows but lifetime production is higher as such animals usually have good fertility and survive longer. There is now extensive evidence that as long as the AFC is >23 months then future performance is not adversely influenced. On the other hand, delayed first calving >30 months is associated with poor survival. Underfeeding of young heifers reduces their milk production potential and is a greater problem than overfeeding. Farmers are more likely to meet the optimum AFC target of 23 to 25 months if they monitor growth rates and adjust feed accordingly.
    Keywords average daily gain ; beef ; beef cattle ; breeding ; calving ; conception rate ; cows ; dairy heifers ; dairy herds ; economic performance ; farmers ; farms ; Holstein ; infectious diseases ; lactation ; longevity ; milk yield ; nutrient deficiencies ; overfeeding ; pregnancy ; puberty ; rearing ; restricted feeding ; semen ; United States
    Language English
    Dates of publication 2014-05
    Size p. 91-104.
    Publishing place Cambridge University Press
    Document type Article
    ZDB-ID 2257920-5
    ISSN 1751-732X ; 1751-7311
    ISSN (online) 1751-732X
    ISSN 1751-7311
    DOI 10.1017/S1751731114000755
    Database NAL-Catalogue (AGRICOLA)

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  6. Article: Does an on-site satellite laboratory reduce surgical delays? A study of delays in a same day surgical center.

    Johnson, K F

    AORN journal

    1994  Volume 59, Issue 6, Page(s) 1275–6, 1279–82, 1285–90

    MeSH term(s) Adult ; Ambulatory Surgical Procedures ; Diagnostic Tests, Routine ; Female ; Humans ; Interdepartmental Relations ; Laboratories, Hospital/organization & administration ; Male ; Operating Rooms ; Program Evaluation ; Time and Motion Studies ; Utah
    Language English
    Publishing date 1994-06
    Publishing country United States
    Document type Journal Article
    ZDB-ID 603972-8
    ISSN 0001-2092
    ISSN 0001-2092
    DOI 10.1016/s0001-2092(07)64893-5
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Heifer fertility and carry over consequences for life time production in dairy and beef cattle.

    Wathes, D C / Pollott, G E / Johnson, K F / Richardson, H / Cooke, J S

    Animal : an international journal of animal bioscience

    2014  Volume 8 Suppl 1, Page(s) 91–104

    Abstract: The rearing period has a key influence on the later performance of cattle, affecting future fertility and longevity. Producers usually aim to breed replacement heifers by 15 months to calve at 24 months. An age at first calving (AFC) close to 2 years (23 ...

    Abstract The rearing period has a key influence on the later performance of cattle, affecting future fertility and longevity. Producers usually aim to breed replacement heifers by 15 months to calve at 24 months. An age at first calving (AFC) close to 2 years (23 to 25 months) is optimum for economic performance as it minimises the non-productive period and maintains a seasonal calving pattern. This is rarely achieved in either dairy or beef herds, with average AFC for dairy herds usually between 26 and 30 months. Maintaining a low AFC requires good heifer management with adequate growth to ensure an appropriate BW and frame size at calving. Puberty should occur at least 6 weeks before the target breeding age to enable animals to undergo oestrous cycles before mating. Cattle reach puberty at a fairly consistent, but breed-dependent, proportion of mature BW. Heifer fertility is a critical component of AFC. In US Holsteins the conception rate peaked at 57% at 15 to 16 months, declining in older heifers. Wide variations in growth rates on the same farm often lead to some animals having delayed first breeding and/or conception. Oestrous synchronisation regimes and sexed semen can both be used but unless heifers have been previously well-managed the success rates may be unacceptably low. Altering the nutritional input above or below those needed for maintenance at any stage from birth to first calving clearly alters the average daily gain (ADG) in weight. In general an ADG of around 0.75 kg/day seems optimal for dairy heifers, with lower rates delaying puberty and AFC. There is some scope to vary ADG at different ages providing animals reach an adequate size by calving. Major periods of nutritional deficiency and/or severe calfhood disease will, however, compromise development with long-term adverse consequences. Infectious disease can also cause pregnancy loss/abortion. First lactation milk yield may be slightly lower in younger calving cows but lifetime production is higher as such animals usually have good fertility and survive longer. There is now extensive evidence that as long as the AFC is >23 months then future performance is not adversely influenced. On the other hand, delayed first calving >30 months is associated with poor survival. Underfeeding of young heifers reduces their milk production potential and is a greater problem than overfeeding. Farmers are more likely to meet the optimum AFC target of 23 to 25 months if they monitor growth rates and adjust feed accordingly.
    MeSH term(s) Age Factors ; Animal Husbandry ; Animals ; Body Composition ; Breeding ; Cattle/physiology ; Dairying ; Female ; Fertility/physiology ; Lactation/physiology ; Meat ; Pregnancy ; Reproduction/physiology
    Language English
    Publishing date 2014-05
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 2257920-5
    ISSN 1751-732X ; 1751-7311
    ISSN (online) 1751-732X
    ISSN 1751-7311
    DOI 10.1017/S1751731114000755
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Unraveling the recruitment problem: A review of environmentally-informed forecasting and management strategy evaluation

    Haltuch, M.A / Brooks, E.N / Brodziak, J / Devine, J.A / Johnson, K.F / Klibansky, N / Nash, R.D.M / Payne, M.R / Shertzer, K.W / Subbey, S / Wells, B.K

    Fisheries research. 2019 Sept., v. 217

    2019  

    Abstract: Studies describing and hypothesizing the impact of climate change and environmental processes on vital rates of fish stocks are increasing in frequency, and concomitant with that is interest in incorporating these processes in fish stock assessments and ... ...

    Abstract Studies describing and hypothesizing the impact of climate change and environmental processes on vital rates of fish stocks are increasing in frequency, and concomitant with that is interest in incorporating these processes in fish stock assessments and forecasting models. Previous research suggests that including environmental drivers of fish recruitment in forecasting is of limited value, concluding that forecasting improvements are minimal while potential spurious relationships were sufficient to advise against inclusion. This review evaluates progress in implementing environmental factors in stock-recruitment projections and Management Strategy Evaluations (MSEs), from the year 2000 through 2017, by reviewing studies that incorporate environmental processes into recruitment forecasting, full-cycle MSEs, or simulations investigating harvest control rules. The only successes identified were for species with a short pre-recruit survival window (e.g., opportunistic life-history strategy), where the abbreviated life-span made it easier to identify one or a limited set of key drivers that directly impact dynamics. Autoregressive methods appeared to perform as well, if not better, for species with a longer pre-recruit survival window (e.g., seasonal, inter-annual) during which the environment could potentially exert influence. This review suggests that the inclusion of environmental drivers into assessments and forecasting is most likely to be successful for species with short pre-recruit survival windows (e.g., squid, sardine) and for those that have bottlenecks in their life history during which the environment can exert a well-defined pressure (e.g., anadromous fishes, those reliant on nursery areas). The effects of environment may be more complicated and variable for species with a longer pre-recruit survival window, reducing the ability to quantify environment-recruitment relationships. Species with more complex early life histories and longer pre-recruit survival windows would benefit from future research that focuses on relevant species-specific spatio-temporal scales to improve mechanistic understanding of abiotic-biotic interactions.
    Keywords anadromous fish ; climate change ; environmental factors ; life history ; longevity ; models ; sardines ; species recruitment ; squid
    Language English
    Dates of publication 2019-09
    Size p. 198-216.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 406532-3
    ISSN 0165-7836
    ISSN 0165-7836
    DOI 10.1016/j.fishres.2018.12.016
    Database NAL-Catalogue (AGRICOLA)

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  9. Article: Critical assessment of microarray data analysis: the 2001 challenge.

    Johnson, K F / Lin, S M

    Bioinformatics (Oxford, England)

    2001  Volume 17, Issue 9, Page(s) 857–858

    Abstract: Unlabelled: We initiated the Critical Assessment of Microarray Data Analysis (CAMDA) conference to stimulate and evaluate the development of advanced data analysis techniques for microarrays. A standard data set has been released for this data analysis ... ...

    Abstract Unlabelled: We initiated the Critical Assessment of Microarray Data Analysis (CAMDA) conference to stimulate and evaluate the development of advanced data analysis techniques for microarrays. A standard data set has been released for this data analysis challenge. The goal of this challenge is to assess the performance of different analytical methods and at the same time to determine how such methods should be evaluated. We hope this effort will catalyze the discussion of microarray data analysis among the research community of biologists, statisticians, mathematicians, and computer scientists.
    Availability: http://camda.duke.edu.
    MeSH term(s) Computational Biology/methods ; Computational Biology/trends ; Databases, Genetic ; Gene Expression Profiling/methods ; Gene Expression Profiling/trends ; Oligonucleotide Array Sequence Analysis/methods ; Oligonucleotide Array Sequence Analysis/trends
    Language English
    Publishing date 2001-09
    Publishing country England
    Document type Congress ; Evaluation Studies ; Research Support, Non-U.S. Gov't
    ZDB-ID 1422668-6
    ISSN 1367-4803
    ISSN 1367-4803
    DOI 10.1093/bioinformatics/17.9.857
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Developing a user-friendly information network.

    Johnson, K F

    Health progress (Saint Louis, Mo.)

    1989  Volume 70, Issue 1, Page(s) 84–85

    MeSH term(s) Centralized Hospital Services ; Computer Communication Networks ; Hospital Information Systems/organization & administration ; Microcomputers
    Language English
    Publishing date 1989-01
    Publishing country United States
    Document type Journal Article
    ZDB-ID 605925-9
    ISSN 0882-1577 ; 0018-5817
    ISSN 0882-1577 ; 0018-5817
    Database MEDical Literature Analysis and Retrieval System OnLINE

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