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51.
The freezing conditions for preparation of frozen canine semen by the plunging method were investigated with regard to the period of sensitization in liquid nitrogen (LN2) vapor and the height from LN2, and the semen qualities after thawing were compared with those of canine semen prepared by the simple freezer method previously reported by us. In the plunging method, 9 semen straws were prepared under the same conditions, horizontally kept at 5, 7, and 10 cm above the LN2 surface in a styrene foam box for 5, 10, and 15 min, and then plunged into LN2. The semen qualities immediately after thawing were high in the 7 cm/10 min (cooling rate: -4 to -22 degrees C/min) and 10 cm/15 min groups (cooling rate: -6 to -10 degrees C/min). On comparison of frozen semen prepared by the plunging method (7 cm/10 min) with frozen semen prepared by the simple freezer method, sperm motility and viability were significantly higher for the frozen semen prepared by the plunging method. The cooling rate in freezing was higher for the simple freezer method (cooling rate: -6 to -50.9 degrees C/min) than the plunging method. Based on these findings, horizontal placement of canine semen straws above LN2 to reduce the temperature at a slow cooling rate of about -10 degrees C/min, followed by plunging into LN2 after sensitization for 10-15 min, provides good semen qualities after thawing.  相似文献   
52.
Commercial western blot (WB) assay was used to detect serum antibodies specific to Echinococcus multilocularis in 23 horses in which infection was confirmed by postmortem inspection at a slaughterhouse. Livers contained from 1 to >20 nodular lesions; foci diameter ranged from 1 to 25 mm. Antibody tests of serum from all 23 animals were negative for antigen bands at 7, 16, 18, and 26-28 kDa, which show specificity in the serum of human patients. However, sera from two infected horses with the largest nodules (diameter, 25 mm) showed positive response to one of the 22-kDa and 30-kDa antigen bands. It may be possible to diagnose E. multilocularis infection in horses based on the detection of these bands on commercial WB assay.  相似文献   
53.
A 2-year-old East Friesian sheep imported from Australia exhibited severe anemia after contagious pustular dermatitis in Hokkaido, Japan. Hemoplasma infection was confirmed in blood smears. Both Mycoplasma ovis and 'Candidatus Mycoplasma haemovis' were detected by PCR and sequence analyses. In the epidemiological analysis, dual pathogens were detected in 6 of 12 (50.0%) sheep imported from Australia with the infected ewe at the same time, 1 of 5 (20.0%) sheep introduced from a domestic farm in Hokkaido, and in 1 of 16 (6.3%) sheep from an epidemiologically unrelated ranch. It is the first clinical case of sheep to confirm coinfection of these pathogens in Japan.  相似文献   
54.
Bovine neosporosis, caused by Neospora caninum is a leading cause of abortion in cattle. We postulated that neosporosis could lead to fetal death and mummification. Fifteen mummified fetuses were tested by polymerase chain reaction (PCR) for the mutation in the bovine SLC35A3 gene that causes complex vertebral malformation (CVM) and the pNC-5 gene which identifies N. caninum infection. DNA was extracted from the mummified fetuses and the sex of the mummies was determined by PCR. The CVM mutation was not detected in the mummified fetuses, but 4 fetuses were positive for N. caninum infection. The ages of the mummies with N. caninum infection were 100, 113, 123, and 131 days. Twelve of the 15 mummified fetuses were male. To our knowledge, this is the first detection of N. caninum as a possible cause of bovine fetal mummification.  相似文献   
55.
The incidence of different types of luteal activity postpartum and their effect on reproductive performance were studied in 21 postpartum dairy cows. Progesterone concentrations in defatted milk collected 3 times a week were determined by EIA. Reproductive tract examination was undertaken every other week postpartum. Body weight and body condition score (BCS) were measured before and after calving and the average 100-day milk yield was calculated. Nine (42.9%) cows had normal ovarian activity (first luteal activity < or = 50 days postpartum followed by regular cycles), 5 (23.8%) had prolonged luteal phase (PLP; ovarian cycle with luteal activity > or = 20 days pre-service) and in 7 (33.3%) cows the first luteal activity was shown later than 50 days postpartum (DOV). When compared with normal cows, both PLP and DOV had longer interval to first insemination (63.1 +/- 22.0 days versus 77.6 +/- 21.6 and 93.0 +/- 22.3 days, P<0.05 and P<0.01, respectively), lower first insemination conception rate (88.9% versus 0.0% and 57.1%, P<0.01 and P<0.05, respectively) and greater BCS loss (0.81 +/- 0.2 versus 1.05 +/- 0.21 and 1.04 +/- 0.10, respectively, P<0.01). Cows with PLP showed longer interval to uterine involution than normal and DOV groups (54.0 +/- 8.3 days versus 42.4 +/- 5.5 and 43.3 +/- 8.3 days, respectively, P<0.01) and higher 100-day milk yield (38.8 +/- 2.7 kg versus 33.6 +/- 4.7 and 29.9 +/- 6.1 kg, respectively, P<0.01). In conclusion, more than half of the cows had abnormal luteal activity postpartum, which adversely affected reproductive performance.  相似文献   
56.
Artificial insemination with frozen cauda epididymal sperm was performed in cats. Sperm were transmigrated from the epididymides in 10 male cats. The mean sperm motility and viability were 67% and 82.5%, respectively, and 11.6 x 10(7) sperm were recovered. The mean sperm motility after thawing was 24.0%. Eleven female cats received unilateral intrauterine insemination of 5 x 10(7) sperm, and the conception rate was 27.3% (3/11). This was the first case of conception obtained with frozen epididymal sperm in cats.  相似文献   
57.
The present study was undertaken to develop a novel, practical and simple procedure for enzyme‐linked immunosorbent assay of fecal estrone derivatives (estrone, estrone sulfate and estrone glucuronide) in dairy cows. Fecal solution, prepared by mixing feces with borate buffer, was applied directly to wells without extraction, and incubated with anti‐estrone antibody and horseradish peroxidase‐labeled estrone. Estrone sulfate was used as the standard. The sensitivity of the assay was estimated as 0.15 ng/mL (0.6 ng/g). The intra‐assay and inter‐assay coefficients of variation were 5.3–8.1% and 13.4–15.7%, respectively. The recovery rate was 78–102%. Only 4 h were needed to complete an assay to measure fecal estrone derivative concentrations. A significant positive correlation was established between plasma estrone sulfate concentrations and fecal estrone sulfate equivalent concentrations. When fecal estrone sulfate equivalent concentrations were measured in pregnant dairy cows, a gradual increase from day 150 of pregnancy, and subsequent drastic increases from day 240 to calving date were observed. These results suggest that the direct enzyme immunoassay procedure developed in the present study is a practical and reliable method for measuring fecal estrone derivative concentrations.  相似文献   
58.
 Rice reflectance was measured to determine the spectral regions most sensitive to leaf blast infection with a multispectral radiometer. As disease severity increased, reflectance also increased in the 400–500 nm (blue), 570–700 nm (red), and 900–2000 nm regions but decreased in the 500–570 nm and 700–900 nm regions. The increased reflectance in the blue and red regions may be attributed to decreased chlorophyll and carotenoid contents in response to the blast infection. The maximum and minimum reflectance differences occurred at 680 nm and 760 nm for the nondiseased and diseased rice, respectively. The spectral location of maximum sensitivity was 675 nm regardless of disease severity. Rice reflectance ratios were evaluated as indicators of leaf blast severity. Two ratios, R550/R675 (reflectance at 550 nm divided by reflectance at 675 nm), and R570/R675 quantified the significant disease severity. These wavelengths were selected based on the sensitivity minima and maxima. The ratios of nondiseased rice plants varied depending on growth stage. The variation in ratios must be considered when they are used to estimate leaf blast severity. Received: April 2, 2002 / Accepted: August 12, 2002  相似文献   
59.
OBJECTIVE: To establish novel polymorphic markers for analysis of loss of heterozygosity (LOH), so as to study the possible involvement of BRCA2 in mammary tumors obtained from dogs. SAMPLE POPULATION: Blood samples, mammary gland specimens, or mammary tumors from 3 tumor-bearing dogs and 10 tumor-free dogs. PROCEDURES: Nucleotide sequence analysis was performed with a DNA autosequencer. Loss of heterozygosity analysis was performed for markers established in the present study. The expression level of canine BRCA2 was quantified by real-time PCR analysis. RESULTS: 3 novel microsatellite markers with high heterozygosity rates (> 50%) were established, and the previously reported marker for canine BRCA2 gene locus was improved. These markers were used for the analysis of DNA from formalin-fixed and paraffin-embedded samples. By use of these markers, LOH in canine BRCA2 was identified as a result of recombination. In mammary tumor DNA that corresponded to the LOH-positive dog, the level of canine BRCA2 expression was decreased compared with that of nonneoplastic mammary gland tissue; the open reading frame contained 4 missense variations, 1 insertion variation, and 1 silent variation, some of which were localized to functional domains. CONCLUSIONS AND CLINICAL RELEVANCE: 3 novel polymorphic markers were developed for LOH analysis of canine BRCA2 and identified a dog with LOH with some variations in the functional domains. These markers could be useful for assessing the relevance of BRCA2 variation in mammary tumors of dogs.  相似文献   
60.
Direct enzyme immunoassay of progesterone in bovine plasma   总被引:2,自引:0,他引:2  
The present study was undertaken to develop a novel, practical and simple procedure for enzyme immunoassay (EIA) of plasma progesterone in cows. Diluted plasma was heated for 70°C for 30 min and applied directly to wells of a microtitre plate without extraction. Then plasma was incubated with antiprogesterone antibody and horseradish peroxidase‐labeled progesterone. The sensitivity of the assay was estimated as 4.4 pg/mL (0.11 pg/well). The intra‐assay and interassay coefficients of variation were 5.7–19.1% and 6.6–19.3%, respectively. When 0.3, 1 and 3 ng of progesterone were added to plasma, the recovery rates ranged between 79.9 and 108.4%. Only 4 h were needed to complete an assay to measure progesterone concentration. To apply the present direct EIA, progesterone concentration in plasma was assayed in crossbred cows used for the embryo transfer program. During insertion of controlled‐internal drug release (CIDR), progesterone concentrations were kept at a high level, although the removal of CIDR with treatment of dinoprost trometamine reduced progesterone concentration drastically. These results suggest that the present direct EIA is a practical and suitable method for measuring the plasma concentration of progesterone.  相似文献   
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