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51.
The immune responses of hypothyroid dogs to canine thyroglobulin (cTg) were evaluated for the proliferative ability of peripheral blood mononuclear cells (PBMC). PBMC from three hypothyroid dogs with high titers of thyroglobulin autoantibody (TgAA) and 3 clinically normal dogs were cultured with 5, 10, or 20 microg/ml of cTg for 72 hr. The proliferative responses of the cells were determined by the level of incorporated BrdU. The numbers of cells expressing Thy-1, CD4, CD8 and IgG in the PBMC were counted by the immunofluorescence method. Proliferative responses to cTg were observed in the cells from hypothyroid dogs. The number of cells expressing IgG and CD8 in the hypothyroid dogs tended to be high compared with the clinically normal dogs. The CD4+ cells in cultures from hypothyroid dogs increased depending upon the amount of cTg. There was a significant (P<0.05) positive correlation between the number of CD4+ cells and the concentration of cTg in the cultures from hypothyroid dogs. These findings suggest a possible relationship between canine hypothyroidism and cellular immunity. Loss of self tolerance to thyroid antigens in CD4+ T cells may play an important role in the development of canine hypothyroidism.  相似文献   
52.
Forty-three isolates ofVerticillium lecanii from insects, phytopathogenic fungi and other substrates were tested for vegetative compatibility by observing heterokaryon formation among complementary nitrate-nonutilizing (nit) mutants.nit mutants were isolated from 42/43 strains examined. Twenty-one isolates were self-incompatible, and the remaining 21 isolates were divided into 14 vegetative compatibility groups (VCGs): ten containing only a single strain each, and the remaining four containing two to four isolates each. Members of isolates in each of these VCGs all shared the same IGS haplotype. Further, the isolates within a VCG were correlated with one another in part by fragment patterns of mt-LrDNA, -SrDNA, Bt-2 and H4 region, by PCR-RFLP and -SSCP, but not by dsRNA. Two isolates belonging to VL-J2 have high virulence to aphids, whereas strains from VL-J1 lack this character. These findings indicate that two VCGs (VL-J1 and -J2) may originate from two distinct clonal lineages. Alternatively, high VCG diversity and HSI frequency ofV. lecanii might be associated with an array of distinct lineages. These data not only suggest relationships among DNA polymorphisms, virulence, and VCG, but also demonstrate genetic heterogeneity ofV. lecanii. http://www.phytoparasitica.org posting Sept. 30, 2003.  相似文献   
53.
Two Holstein heifers and a cow were diagnosed with White Heifer Disease by ultrasonography. Case 1 was a 14 month-old heifer with aplasia of both sides of the uterine horn. In case 2, a primiparous cow and case 3, an 18 month-old heifer, both showed aplasia of the right uterine horn. Case 2 became pregnant by artificial insemination at ipsilateral ovulatory follicle and corpus luteum in the left ovary, while case 3 became pregnant by embryo transfer at 7 days after oestrus with contralateral corpus luteum in the right ovary.  相似文献   
54.
Low molecular weight organic acids are widespread and reactive in soils, but their distribution among mineral horizons is uncertain. We investigated the distribution of low molecular weight aliphatic carboxylic acids (LACAs) in three Japanese forest soils, two Acid Brown Forest soils and one Podzolic soil. The total LACAs ranged from 207.3 to 411.8 μmol kg–1 and were abundant in the lower horizons as well as in the surface horizons of these soils. The illuvial horizons of the Podzolic soil were rich in adsorbed oxalic acid and citric acid. Total LACAs were similar in the two subtypes of Brown Forest soils derived from different parent materials but formed under similar vegetation and climate, and were larger than that in the Podzolic soil. Among the volatile LACAs, formic acid and acetic acid dominated the moist horizons containing much organic material, whereas the non-volatile LACAs, the most abundant being oxalic acid and citric acid, increased in the subsurface horizons. The distribution of water-soluble LACAs in the Brown Forest soil profiles was closely correlated with soil acidity.  相似文献   
55.
Rice brown spot (BS), caused by Bipolaris oryzae, causes yield loss and deterioration of grain quality. Using single-nucleotide polymorphism (SNP) markers, we conducted quantitative trait locus (QTL) analysis of BS resistance in backcross inbred lines (BILs) from a cross between an American rice cultivar, ‘Dawn’ (resistant), and ‘Koshihikari’ (susceptible). Four QTLs for BS resistance were detected in a three-year field evaluation, and ‘Dawn’ contributed the resistance alleles at all QTLs. The QTL with the greatest effect, qBSR6-kd, explained 15.1% to 20.3% of the total phenotypic variation. Although disease score and days to heading (DTH) were negatively correlated in all three years, qBSR6-kd was located near a QTL for DTH at which the ‘Dawn’ allele promoted heading. Another BS resistance QTL (qBSR3.1-kd) was unlinked to the QTLs for DTH. Therefore, these two QTLs are likely to be useful for breeding BS-resistant varieties without delaying heading. The other two BS resistance QTLs (qBSR3.2-kd and qBSR7-kd) were located near DTH QTLs at which the ‘Dawn’ alleles delayed heading. The QTLs reported here will be good candidates for developing BS-resistant cultivars.  相似文献   
56.
57.
Laboratory experiments were conducted to investigate (1) the effects of the addition of rice (Oryza sativa. L.) bran to paddy soil on the germination of Monochoria vaginalis (Burm. f.) Kunth, and (2) the relationship between the electric conductivity (EC) of the soil solution and germination. Soil samples were collected at 4 sites in Japan. After flooded soils with rice bran had been incubated for 7?d at 30°C, the soil solution was collected using a porous cup and the EC of the soil solution was measured. The amounts of rice bran added to the soil were 0%, 0.3%, 0.6% and 0.9% (weight(w)/w). In the soil solution obtained, seeds of M. vaginalis were incubated for 3?d at 30°C, and the germination percentage was then analyzed. The addition of rice bran suppressed germination, and the degree of suppression increased with increasing content of rice bran. Although the same amount of rice bran was applied to each soil, the degree of growth suppression by rice bran as well as the EC of the soil solution differed among the soils. In each soil, there was a positive correlation between the amount of rice bran and EC, and the degree of growth suppression significantly increased with an increase in EC. When EC was higher than 150?mS?m?1, seeds of M. vaginalis hardly germinated. There was no significant correlation between the oxidation-reduction potential (Eh) of soil and seed germination, suggesting that EC is a more reliable and convenient indicator than Eh for evaluating the relationship between the addition of organic material and seed germination. In conclusion, the addition of rice bran to soil increases the EC of the soil solution, and EC is one of the factors that suppress the germination of M. vaginalis. The suppressive effect of rice bran on germination is different among soils. This fact is attributed to the difference in EC due to the addition of rice bran. Thus, it is expected that EC can be used as an indicator for determining how much rice bran to add.  相似文献   
58.
The aim of this study was to determine whether the population of lymphocytes expressing CD4 and CD8 molecules changed in the white follicles during atresia in chickens. Frozen sections of healthy, early atretic, advanced atretic and late atretic follicles were immunostained for CD4 and CD8, and the populations of positive cells were analyzed under a light microscope. In the healthy, early atretic and advanced atretic follicles both CD4+ and CD8+ cells were localized in the theca layer, but not in the granulosa layer. However, an influx of CD4+ and CD8+ cells was observed not only in the theca but also in the follicular cavity that was formed by disintegration of the oocyte in late atretic follicles. The frequency of CD4+ T cells in the theca layer did not differ among healthy, early atretic and advanced atretic follicles, but was significantly increased in the late atretic follicles (P < 0.05). The frequency of CD8+ cells showed a pattern of change that resembled that of CD4+ T cells, with a significantly greater population in late atretic follicles than the other follicles (P < 0.05). These results suggest that CD4+ and CD8+ cells are increased in the late atretic follicles, probably to promote the tissue regression.  相似文献   
59.
Fifty-six hamsters with demodicosis were treated with daily oral administration of ivermectin (0.3 mg/kg). Thirty-three cases (58.9%) were cured and 6 cases (10.7%) had improved clinically but needed to continue treatment. Of 5 cases (8.9%) who relapsed within 3 months and were retreated with ivermectin, 4 were cured and 1 needed further treatment. Five cases (8.9%) had improved clinically but died within 3 months. Seven cases (12.5%) had not improved and died within 3 months. Overall 49 (87.5%) hamsters had improved clinically. No significant differences in prognosis of demodicosis were detected according to sex, breed, age and clinical features, but the prognosis of demodicosis in hamsters with concurrent disease was poor.  相似文献   
60.
The abilities of Salmonella serovars to colonize the reproductive organs of chickens and to contaminate eggs were compared. Mature laying hens were inoculated intravenously with 10(5) colony-forming units of Salmonella enteritidis, Salmonella typhimurium, Salmonella infantis, Salmonella hadar, Salmonella heidelberg, or Salmonella montevideo to cause the systemic infection. Salmonella enteritidis was recovered from three yolks of the laid eggs (7.0%), suggesting egg contamination from the transovarian transmission of S. enteritidis. The liver, spleen, and cecum were colonized by each serovar similarly at 4 or 7 days postinoculation (PI), whereas the ovary and preovulatory follicles were colonized by S. enteritidis with significantly (P < 0.05) higher levels than by the other serovars at 4 and 7 days PI. Salmonella enteritidis was recovered from the cloaca and vagina at 2, 4, and 7 days PI and from the other portions of the oviduct at 4 and 7 days PI. In addition, S. enteritidis had been persistent in the peripheral blood for 7 days PI. These results suggest that S. enteritidis is the predominant serovar to colonize the reproductive organs of mature laying hens among six serovars used in this study, reflecting the field situatibn in which the predominant outbreaks of human salmonellosis were caused by S. enteritidis-contaminated eggs recently. The ability of S. enteritidis to colonize the reproductive organs may be one of the reasons that egg contamination with S. enteritidis has increased.  相似文献   
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