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81.
A commercial swineherd in Indiana experienced high death loss of nursery pigs with neurologic disorders for a prolonged period. Polioencephalomyelitis was the consistent histopathological lesion in affected animals. A porcine enterovirus (PEV) classified to group I was isolated from spinal cords and brains collected from the affected animals. The isolate (ISUVDL 200103183) was determined to belong to either serogroup 5 or 6 at the National Veterinary Services Laboratories, Ames, IA. No other significant viral or bacterial agents were isolated from or detected in the animals. A prospective longitudinal serological monitoring of pigs in the index herd for the PEV isolate revealed that colostrum-derived neutralizing antibodies to the virus rapidly declined, and by the age of 21 days the majority of piglets had no or minimal neutralizing antibody against the virus. Seroconversion to the virus then coincided with increased mortality in the herd. Results of diagnostic and cohort observations supported a diagnosis of PEV infection as the cause of the prolonged outbreak of "polio." Investigation into factors that may be contributing to the prolonged problem is currently in progress.  相似文献   
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Frozen-thawed (FT) boar sperm have a reduced fertile life, due in part to a capacitation-like status induced by cooling. Reversal of this cryocapacitation in vitro by exposure to boar seminal plasma (SP) has been demonstrated. The objective of these studies was to determine the effect of SP on the ability of FT sperm to create an oviductal sperm reservoir following artificial insemination (AI). In Experiment one, 35 pre-pubertal gilts were injected (IM) with 400 IU eCG plus 200 IU hCG to induce oestrus. At detection of oestrus, gilts were inseminated with 3 x 10(9) live sperm, either fresh (FS; n = 13), FT (n = 10), or FT supplemented with 10% v/v SP (n = 12). Gilts were killed 8 h later, their reproductive tracts recovered and the uterotubal junctions (UTJs) flushed to recover sperm. Fewer (p < 0.01) sperm were recovered following FT, compared to FS, inseminations, and there was no evident effect of SP. In Experiment two, 30 pre-pubertal gilts received IM injections of 1000 IU eCG followed by 5 mg pLH 80 h later to control time of ovulation. Gilts were inseminated with 3 x 10(9) live FS sperm (n = 6), FT sperm (n = 15) or FT sperm plus 10% SP (n = 9) at 12 h before ovulation and then sacrificed 8 h later. The UTJs were dissected and flushed for sperm recovery. Fewest (p < 0.001) sperm were recovered following FT insemination and there was no evident effect of SP. These data demonstrate that the size of the sperm reservoir is markedly reduced in gilts inseminated with FT sperm. However, the lack of effect of SP suggested that either it did not reverse cryocapacitation or that such a reversal does not impact the in vivo ability to create a sperm reservoir.  相似文献   
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Bovine viral diarrhea (BVD) is one of the economically important diseases of cattle. For many years, different types of vaccines have been commercially available, yet this disease is hard to control in high-density population areas. Detection and isolation of bovine viral diarrhea virus (BVDV) from any potential reservoir is vital, especially when considering virus eradication from a herd or locale. One potential source is wild ruminants. Ear notches and lymph nodes were collected from the wild population of white-tailed deer (Odocoileus virginianus) during deer hunting season in Indiana and tested for BVDV with a commercial BVD antigen capture enzyme-linked immunosorbent assay. Two samples out of 745 collected samples were positive, and subsequently cp and ncp BVDV was isolated from 1 ear notch and 1 lymph node. These isolates were genotyped as type 1a and 1b based on sequence analysis of the 5' untranslated region (UTR). The results of the present study indicate that the prevalence of BVDV in the white-tailed deer population of Indiana is about 0.3%. Wild ruminants infected with BVDV should be taken into consideration during an eradication program of BVDV from the livestock population.  相似文献   
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Assessment of urine levels of luteinizing hormone (LH) for predicting the reproductive status of animals is in practice. The aim of this study was to predict the period of ovulation based on the urine levels of LH for timed‐artificial insemination to increase the conception rate in buffaloes, which are naturally silent‐oestrous animals. Level of LH in urine was assessed using ELISA, and a cut‐off LH concentration for prediction of ovulation period was obtained using receiver operating characteristic analysis. Artificial insemination was performed before‐ and after ‐positive prediction of ovulation period adopting this method, and the rates of conception were assessed. Urine LH level of 105 mIU/ml (n = 14) was derived as a cut‐off concentration which predicts the ovulation period. The buffaloes in the positively predicted group (day 1 or 2) inseminated via intracervical route had an increase in the conception rate (83.33%); however, the insemination in the before‐positive‐prediction group resulted in poor conception rates (day 0; 16.66%) compared to that of the naturally inseminated group (day 0; 75.0%). In conclusion, the urinary LH would possibly be a fairly reliable predictor of the ovulation period. The day when cut‐off LH concentration is obtained may be taken as the most favourable time for artificial insemination, so as to attain a much better rate of conception in the buffalo.  相似文献   
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In this study, motility and oxidative–antioxidant capacity (thiobarbituric acid‐reactive substance level [TBARS], superoxide dismutase [SOD], catalase [CAT] and glutathione reductase [GR]) of beluga sturgeon (Huso huso) sperm, stored for 6 days at ?80°C, were evaluated. After 2 days of storage, sperm motility was significantly decreased (no motile sperm were observed after 6 days of storage; < .05), while TBARS and SOD values were significantly increased (< .05). CAT and GR activities did not show significant changes among storage times (> .05). Furthermore, all investigated parameters showed a significant difference between semen stored at 4°C (control) and ?80°C during in vitro storage (< .05). Data from this work can potentially be useful in sturgeon sperm cryobanking.  相似文献   
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