A context for recruitment correlations: why marine fisheries biologists should still look for them     

A. V. TYLER 《Fisheries Oceanography》1992,1(1):97-107

In many cases when ecologists want to investigate a process, they often look for the best system on which to conduct the research, "best" meaning that the possibility of discovering mechanisms is optimized or made easier in some way. In fisheries we do it backwards. The species and system are given to us by economics, and we then fly in the face of the difficult circumstances to find mechanisms that are elusive anyway. These difficult circumstances constitute in some sense the first set of statistical problems. Using examples from the Northeast Pacific, I review the characteristics of cohort time series that make some species more tractable; propose a conscious process of conceptualization to assist in the formulation of clear, germane hypotheses; highlight the contrast between modeling in the sense of statistical fitting versus simulation models of processes; explore how the first round of models integrates with the second round of planning for new data collection at sea and in the lab; and, finally, propose how to judge success in terms of an operational approach.  相似文献   

福建黄兔繁殖性状相关研究   总被引：5，自引：0，他引：5  

徐龙  林和官 《福建畜牧兽医》1994,16(2):13-15

本文对３１０只母兔的繁殖性状进行了测定分析，结果表明；妊娠期与产仔数、产活仔数及活仔窝重呈负相关，相关系数分别为－０．４２６＊、－０．３５０＊和－０．５１５头４胎内母兔，胎次对产仔性能无影响，对母兔泌乳性能有一定影响。同样条件下胎次增加。泌乳性能提高，第３胎较第２胎有显著提高。  相似文献   

Court modifications of covenants against competition.     

H W Hannah 《Journal of the American Veterinary Medical Association》1992,201(3):399-401

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Proliferative response of mammary gland mononuclear cells to recombinant bovine interleukin-2.     

P M Torre  P K Konur  S P Oliver 《Veterinary immunology and immunopathology》1992,32(3-4):351-358

Methods of augmenting bovine mononuclear cell responsiveness during physiological transitions of the udder may enhance resistance of the mammary gland to intramammary infections. Interleukin-2 is required for proliferation of T-lymphocytes and may contribute to B-lymphocyte proliferation. Recombinant bovine interleukin-2 (rBoIL-2) was evaluated as a potential immunoenhancer of bovine mammary gland mononuclear cells. Bovine mononuclear cells were isolated from five primiparous Holstein cows at 14-18 and 28-32 days of involution and at 7-13 days prior to parturition. Bovine blood and mammary gland mononuclear cells were highly responsive to rBoIL-2. Response of mammary gland mononuclear cells to rBoIL-2 was comparable with response of blood mononuclear cells. These data suggest that rBoIL-2 may be an effective immunoenhancer of bovine mononuclear cells during the non-lactating and prepartum periods.  相似文献   

Use of netting and whitewash spray to protect papaya plants against Nivun Haamir (NH)-dieback disease     

A. Franck  M. Bar-Joseph 《Crop Protection》1992,11(6):525-528

A disease causing the decline of papaya (Carica papaya) plants was noticed in the Jordan Valley in 1982. The disease caused severe yellowing of the upper leaves and dieback of the apex. The disease was not transmissible mechanically and continued efforts to associate viruses and viroids have so far been unsuccessful. Epidemiological observations suggested that the disease is airborne and probably caused by a mollicute. In order to test this hypothesis, plots were covered by an insect-proof net and with white nets providing 15, 30 and 50% shade. The 30%, 50% and insect-proof nettings provided complete protection, and the 15% netting reduced disease incidence to <2%, compared with>37% in the uncovered control plot. Spraying plants at weekly intervals with a commercial whitewash solution was also found to be effective in reducing disease incidence. The advantages of using a range of netting field treatments as a simple means for obtaining information on the epidemiological nature of a new disease are described.  相似文献   

Pulmonary artery and aortic pressure changes during high intensity treadmill exercise in the horse: effect of frusemide and phentolamine.     

B K Erickson  H H Erickson  J R Coffman 《Equine veterinary journal》1992,24(3):215-219

Intravenous frusemide (1.0 mg/kg bwt) or phentolamine (0.33 mg/kg bwt) was given to 7 horses 1 h before exercise and their effects on pulmonary artery and aortic pressure changes during strenuous exercise were examined. Short-term near-maximal treadmill exercise (10 m/sec, 3 degrees incline) produced increases in heart rate, mean pulmonary artery pressure (PAP), mean aortic pressure (AP), and packed cell volume (PCV). Frusemide did not affect heart rate, PAP or PCV during exercise. Frusemide significantly decreased mean AP by 10 to 15 mmHg during exercise. Phentolamine produced an increase in heart rate relative to control only early in exercise but not during later, more strenuous, exercise. Phentolamine had no statistically significant effect on AP, PAP, or PCV, but a significant reduction was observed between 180 and 230 sec of exercise when PAP and AP were standardised against heart rate. Frusemide did not prevent horses from haemorrhaging during exercise in this study. Treatment with phentolamine did not sufficiently reduce the PAP and AP to test our hypothesis that a reduction in PAP and AP would eliminate EIPH.  相似文献   

Large granular lymphoma in an FIV-positive and FeLV-negative cat     

P. Buracco  R. Guglielmino  O. Abate  V. Bocchini  E. Cornaglia  D. B. DeNicola†  M. Cilli  P. Ponzio 《The Journal of small animal practice》1992,33(6):279-284

The clinical course of a feline leukaemia virus (FeLV)-negative and feline immunodeficiency virus (FIV)-positive cat affected with a large granular lymphocyte lymphoma is presented. Cyto-logical examination showed neoplastic cells in the pleural effusion and in two abdominal masses. Bone marrow and peripheral blood were moderately involved and chemotherapy was used to control the tumour. Cytochemistry, immunohis-tochemistry and ultrastructural studies were applied to define the cellular lineage; cytochemistry suggested a T-cell lineage.  相似文献   

A recombinant-based feline immunodeficiency virus antibody enzyme-linked immunosorbent assay.     

B Mermer  P Hillman  R Harris  T Krogmann  Q Tonelli  W Palin  P Andersen 《Veterinary immunology and immunopathology》1992,35(1-2):133-141

We have developed an antibody detection enzyme-linked immunosorbent assay (ELISA) for the identification of animals infected by feline immunodeficiency virus (FIV). The ELISA solid-phase antigen consists of recombinant FIV gag proteins expressed in bacteria. The proteins are purified from bacterial lysates as insoluble inclusion bodies. In the case of bacterially expressed p24gag, it is shown that all of the linear, sequential epitopes presented by viral p24 during infection are retained. Purified preparations can be substituted for solid-phase whole virus in the IDEXX PetChektm immunoassay. The antibody ELISA duplicates the sensitivity and specificity of the whole virus based PetChek plate assay.  相似文献   

Immunocytochemical Study of the Ultimobranchial Tubule in Wistar Rats     

E. Conde    A. M. Moreno    I. Martin-Lacave  A. Fernandez y H.  Galera 《Anatomia, histologia, embryologia》1992,21(1):94-100

A systematic immunohistochemical study of the ultimobranchial tubule (UBT) has been carried out in 45 Wistar rats of different ages (0, 5, 10, 15, 20, 25, 30, 60 and 120 days). The existence of calcitonin immunoreactive cells in the UBT wall has been demonstrated in a 5-days old rat. In addition, immunohistochemical studies for thyroglobulin revealed positive staining in follicular cells connected to the UBT and, occasionally, in isolated cells lying within solid clusters from the UBT. These last results together with the continued and repeated existence of numerous mitosis and PAS (+) microfollicles, apparently rising from the UBT, support the hypothesis that the ultimobranchial body (UBB) may contribute partially to the formation of a part of the follicular component.  相似文献   

Dietary preferences of domestic ruminants (cattle, sheep, goats) grazing on natural Sahelian and Sudano-Sahelian ranges. IV. Attempted description of the diet by micro-histological analyses of samples collected by shepherds, esophageal boluses and feces from cattle and sheep     

H Planton 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1989,42(2):245-252

A research program to study tropical pastures used by domestic livestock was implemented in Senegal. During field studies, numerous information was collected together with many samples with three main aims: pasture composition, diet composition and relationship between each other. The so-called method of epiderms, more often used in temperate areas, was chosen for analyzing and comparing the botanical composition of 105 samples, e.g., shepherd's hand-picking, alimentary bolus and faeces collected during a twelve-month period. In view of the results, some methodological problems are raised and discussed.  相似文献