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91.
Cushing's disease caused by pituitary corticotroph adenoma is a common endocrine disease in dogs. A characteristic biochemical feature of corticotroph adenomas is their relative resistance to negative feedback by glucocorticoids. In this study, we examined gene expression related to adrenocorticotropic hormone (ACTH) production and secretion, and the negative feedback by glucocorticoids in canine corticotroph adenoma. We used resected corticotroph adenomas from 10 dogs with Cushing's disease. In order to investigate the alteration of gene expression between corticotroph adenoma and normal corticotrophic cells, ACTH-positive cells in the anterior lobe were microdissected using a laser-capture microdissection system, and mRNA levels of proopiomelanocortin (POMC), corticotropin releasing hormone receptor 1 (CRHR1), glucocorticoid receptor (GR), mineralocorticoid receptor (MR), and 11 beta hydroxysteroid dehydrogenase (11HSD) type 1 and type 2 were determined using real-time RT-PCR. POMC, CRHR1, and 11HSD2 mRNA levels in corticotroph adenoma were greater than those in normal corticotrophic cells (POMC, 5.5-fold; CRHR1, 4.9-fold; 11HSD2, 4.2-fold, P<0.01, respectively). MR and 11HSD1 mRNA levels in corticotroph adenoma were lower than those in normal corticotrophic cells (MR, 2.2-fold; 11HSD1, 2.9-fold, P<0.01, respectively). GR mRNA levels did not differ between corticotroph adenoma and normal corticotrophic cells. Our results may help to understand the increased ACTH production and the resistance to negative feedback suppression by glucocorticoids in canine corticotroph adenomas. These changes in gene expression may have a role in the growth of canine corticotroph adenoma, and help elucidate the pathophysiology of dogs with Cushing's disease.  相似文献   
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93.
SUMMARY: Cathepsin S was purified from carp hepatopancreas to homogeneity up to 300-fold. The amino acid sequence of its NH2-terminus was determined to be V-P-D-A-M-D-W-Y-N-K-G-Y-V-T-D-V-K-N-Q. On the contrary, that of purified cathepsin L from carp hepatopancreas was to be V-P-N-S-L-D-W-R-E-K-G. Purified cathepsin S consisted of a single chain with 37 kDa estimated by sodium dodecylsulfate–polyacrylamide gel electrophoresis. The enzyme had strong hydrolytic activity toward Z-Phe-Arg-MCA with the pH optimum of 7.0, but this lacked the ability to hydrolyze most of the other MCA substrates. The optimum pH of cathepsin S for protein substrate (carp myosin heavy chain) was also to be pH 7.0. These properties of purified cathepsin S obviously differ from cathepsins B and L. The enzyme activity was totally inhibited by E-64, leupeptin, 5–5'-dithiobis (2-nitro-benzoic acid) and p -tosyl-lys chloromethylketone as well.  相似文献   
94.
To clarify the effect of nutritive conditions on changes in immune cells in Japanese Black (JB) calves during the growth period, leukocyte populations were analyzed in ten healthy JB calves managed in one herd. The calves were divided into two groups: five calves in Group 1 were given insufficient nutrition, and the other five calves in Group 2 received adequate nutrition. The levels of serum total cholesterol and glucose were significantly lower in Group 1 than in Group 2 at 1 month. The numbers of CD3+, CD4+ and CD8+ cells tended to be lower in Group 1 than in Group 2 at months 1 and 2, and the difference in CD4+ was significant at month 2. The number of MHC class-II(+high) cells was significantly lower in Group 1 than in Group 2 at months 1 and 2. These results suggest that adequate nutrition might stimulate an increase in immune cells in calves during the growth period.  相似文献   
95.
The effects of alpha-cyclodextrin-horseradish oil complex (CD-HR) on methane production and ruminal fermentation were studied in vitro and in steers. In the in vitro study, diluted ruminal fluid (30 mL) was incubated anaerobically at 38 degrees C for 6 h with or without CD-HR, using cornstarch as substrate. The CD-HR was added at various concentrations (0, 0.17, 0.85 and 1.7 g/L). Treatment affected neither the pH of the medium nor the number of protozoa. Total VFA increased in a linear manner (P = 0.02), and NH3-N decreased quadratically (P = 0.04) as the concentration of CD-HR increased from 0.17 g/L to 1.7 g/L. Molar proportions of acetate decreased in a linear manner (P = 0.03), and propionate increased linearly (P = 0.008) with increasing concentrations of CD-HR. Production of methane was inhibited up to 90%, whereas accumulation of dihydrogen was increased 36-fold by 1.7 g/L of CD-HR supplementation relative to controls. The effect of CD-HR on methane production, ruminal fermentation and microbes, and digestibility was further investigated in vivo using four Holstein steers in a crossover design. The CD-HR supplement was mixed into the concentrate portion of a (1.5:1) Sudangrass hay plus concentrate mixture that was fed twice daily to the steers. Ruminal samples were collected 0, 2, and 5 h after the morning feeding. No effects of CD-HR supplementation on ruminal pH (P = 0.63) or protozoal numbers (P = 0.44) were observed. Molar proportion of acetate was decreased (P = 0.04) and propionate was increased (P = 0.005) by CD-HR treatment. Molar proportion of butyrate was increased (P = 0.05) in CD-HR-supplemented steers. Ruminal NH3-N was decreased (P = 0.05) by treatment. Blood plasma glucose concentration was increased (P = 0.02) and urea-N was decreased (P = 0.04) with CD-HR supplementation. Daily DMI was decreased (P = 0.04), and apparent digestibility of DM (P = 0.13), NDF (P = 0.14), and CP tended (P = 0.14) to be increased by treatment. Methane production was decreased (P = 0.03) by 19%, and the number of methanogens was also decreased (P = 0.03). Although N retention (P = 0.11), total viable bacteria (P = 0.15), and sulfate-reducing bacteria (P = 0.17) were not significantly altered by treatment, tendencies for increases were noted with CD-HR supplementation. The number of cellulolytic (P = 0.38) and acetogenic bacteria (P = 0.32) remained unchanged by treatment. These results indicate that CD-HR supplementation can be used to decrease methane production in steers.  相似文献   
96.
OBJECTIVE: To determine whether small intestinal ischemia and reperfusion induces bacterial translocation and proinflammatory cytokine response in either the systemic or portal circulation in dogs. ANIMALS: 17 healthy adult Beagles. PROCEDURE: The superior mesenteric artery (SMA) was occluded for 0 (group-3 dogs), 30 (group-1 dogs), or 60 (group-2 dogs) minutes, followed by reperfusion for 180 minutes; serum lactate and endotoxin concentrations and tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and IL-6 activities in the systemic and portal circulation and intramucosal pH were measured at various time points. RESULTS: In group-2 dogs, TNFalpha activity was found to be significantly increased in the portal circulation, peaking at 60 minutes of reperfusion; TNF-alpha activity, in the systemic circulation, gradually increased from 60 minutes of reperfusion to the end of the experiment; however, the increase was not significant. In group-1 and -2 dogs, IL-6 activities significantly and gradually increased in the systemic and portal circulation during the reperfusion phase, and the magnitude of these increases was dependent on the duration of the ischemic phase. There were no significant changes in IL-1beta activity or endotoxin concentration in any dog group. CONCLUSIONS AND CLINICAL RELEVANCE: Results of the our study indicate that intestinal ischemia and reperfusion leads to significant increases of the circulating TNF-alpha and IL-6 activities, depending on the duration of the ischemia phase, in the absence of detectable endotoxin in the circulation. This finding suggests that intestinal ischemia and reperfusion induces a systemic proinflammatory cytokine response in dogs.  相似文献   
97.
The pathogenic races of 450 cultures of Xanthomonas oryzae pv. oryzae, isolated from eight locations in the inland mountainous area of Hiroshima Prefecture during 2000 to 2003, were determined with a set of Japanese differentials. The rice cultivars infected with the bacterium are thought to be in the Kinmaze group, which does not have any resistance genes. Five Japanese races IA, IB, II, V, and VII occurred across the area, although the composition of the races in each location altered during the surveyed 4 years.  相似文献   
98.
Effects of electro-acupuncture (EA) stimulation on the rhythm of the autonomic nervous system in dogs were studied. Six healthy beagles were used in this study. Each dog was separately kept in a cage, and repeatedly exposed to light for 12 hr and dark for 12 hr alternately. Fixed subject dogs were stimulated by use of 5-V, 250-musec, 2-Hz biphasic square pulses for 15 min at the Xuan Shu (GV-5) and Bai Hui (GV-20) points on the spine. After EA stimulation, electrocardiogram was recorded for 24 hr. From the electrocardiogram data, the heart rate (HR), coefficient of variation in the R-R intervals (CVRR; index of autonomic nervous activity), power of high frequency component (HF; index of vagal nervous activity), and ratio of powers of the low and high frequency components (LF/HF; index of sympathetic nervous activity) were obtained. Cosinor analysis demonstrated that these indices exhibited a significant rhythmicity (P<0.05), irrespective of EA stimulation. In LF/HF, EA stimulation advanced the acrophase (from 22:55 to 21:33, P=0.012), and elevated the midline-estimating statistic of rhythm (from 0.653 to 0.725, P=0.006). However, there was no significant difference in HR, CVRR, or HF. In conclusion, EA stimulation markedly influenced the rhythm of sympathetic nervous system in dogs.  相似文献   
99.
Glutamate decarboxylase (GAD) is the primary enzyme in the brain that catalyzes the synthesis of gamma-aminobutyric acid (GABA), the main inhibitory neurotransmitter. There are two isoforms named according to their molecular weights, GAD67 and GAD65, which are encoded by GAD1 and GAD2, respectively. To investigate the association between GAD genes and temperament in domestic dogs, Canis familiaris, we sequenced the full lengths of the coding regions of these genes and identified three single nucleotide polymorphisms (SNPs) in GAD1 and one in GAD2. When comparing genotype and allele frequencies of SNPs among five breeds with different behavioral traits, statistically significant interbreed differences were observed for three SNPs in GAD1. These results suggest that GAD1 SNPs may be useful for behavioral genetic studies in dogs.  相似文献   
100.
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