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131.
The peroxisome proliferator‐activated receptor‐γ coactivator‐1 α (PGC‐1 α) induces mitochondria biogenesis in skeletal muscles. To determine the relationships between PGC‐1 α and the muscle fiber types, the expression levels of PGC‐1 α were analyzed in porcine and bovine skeletal muscles. As a first step, the nucleotide sequences of the porcine and bovine PGC‐1 α were determined. The porcine and bovine PGC‐1 α cDNA encoded 796 amino acid sequences and showed 95.1% identity between the two species. The expression levels of the PGC‐1 α mRNA were analyzed in the same 10 skeletal muscles from four pigs and three cattle. The contents of porcine and bovine PGC‐1 α were higher in the tongue, masseter and diaphragm, and lower in the Biceps femoris, semimembranosus, Longissimus thoracis and semitendinosus muscles. The contents of myosin heavy chain slow‐type protein (MyHC‐slow) were also determined in the same muscles by ELISA. The analysis of MyHC‐slow showed results similar to those for the PGC‐1 α contents in all of the muscles except for the tongue. The content of MyHC‐slow in the tongue was the lowest among the porcine muscles, and moderate among the bovine muscles. The results suggest that PGC‐1 α relates to the development of oxidative muscle fibers, but is not the principal factor in determining type I fiber content.  相似文献   
132.
The aim of the present study was to compare the expression of adipose tissue mRNA related to glucose metabolism between Japanese Black steers (n = 5) and Holstein steers (n = 5). We examined the expression of the resistin, tumor necrosis factor‐α (TNF‐α), glucose transporter 1 (GLUT1) and growth hormone receptor (GHR) genes using real‐time polymerase chain reaction of cDNA in adipose tissue. The cDNA sequence identified by 5′/3′‐rapid amplification of cDNA and the deduced amino acid sequence were highly conserved in human, porcine and murine resistin. Expression of resistin mRNA was significantly greater in Holstein steers than in Japanese Black steers. In contrast, expression of TNF‐α mRNA was slightly greater in Japanese Black steers. Expression of GHR mRNA was significantly greater in Japanese Black steers compared with the Holstein steers, although there was no significant difference in the expression of GLUT1 mRNA. However, the plasma non‐esterified fatty acid (NEFA), glucose, insulin and growth hormone concentrations did not differ between Japanese Black and Holstein steers. The present results show that there is a difference in the expression level of mRNA related to glucose metabolism between Japanese Black steers and Holstein steers.  相似文献   
133.
In dogs effects of phenobarbital (PB) on hepatic cytochrome P450 (CYP) activities and on concentrations of plasma alpha 1-acid glycoprotein (AGP) were examined. Total body clearance (Cl(B)) of antipyrine and plasma AGP concentrations were monitored during oral PB treatment at a therapeutic dose for 35 days. Cl(B) of antipyrine, which reflects hepatic CYP activities, gradually increased and was maintained at about threefold concentrations compared with that before treatment, suggesting that PB induced CYP activities at a large extent even in a therapeutic dose, necessary for an antiepileptic effect. Plasma AGP concentrations also increased significantly (about fourfold). Dogs were killed at the 35th day of the PB treatment, and hepatic CYP content and enzyme kinetics of several CYPs were determined using liver microsomes. CYP content was about twofold higher than that from untreated dogs. The V(max) values for CYP1A-like activity (ethoxyresorufin O-deethylation), 2B-like activity (ethoxycoumarin O-deethylation), 2C-like activity (tolbutamide hydroxylation) and 3A-like activity (midazolam 4-hydroxylation) were higher (2-4-fold) than that in untreated dogs. In summary, a therapeutic dose of PB for antiepileptic therapy significantly induced hepatic CYPs and plasma AGP in dogs. Therefore, during antiepileptic therapy with PB, special attention must be paid to the pharmacokinetics of drugs simultaneously administered.  相似文献   
134.
Glucocorticoids are reported to bias cytokines to a Th2 phenotype. However, this dogma has been advanced largely from studies utilizing potent glucocorticoid analogs. The current study was conducted to revisit the issue of glucocorticoid modulation of Th1/Th2 cytokine production and evaluate migration inhibitory factor (MIF) mRNA expression in cultured pig splenocytes treated with physiologically relevant concentrations of cortisol (CORT). Dexamethasone (DEX) was included for comparison. In Experiment 1, DEX, at 150 and 300 nM, suppressed concanavalin (ConA)-stimulated IFNgamma at both 12 and 24 h in culture, and IL-10 at 24h (P<0.05). Both 150 and 300 nM CORT suppressed IL-10 at 24 h (P<0.05), but neither concentration affected IFNgamma at 24 h. In Experiment 2, cells were cultured with a broader range of CORT for 48 h following ConA. Parallel cultures with identical treatments also were conducted in separate plates for evaluation of glucocorticoid regulation of MIF mRNA. IFNgamma was reduced by 300 nM DEX at 12, 24, and 48 h (P<0.05), whereas 150 and 300 nM CORT blunted IFNgamma at 24 h (P<0.05), but not 48 h. ConA increased IL-2 (P<0.01), but none of the steroid treatments affected IL-2. At both 12 and 24 h, IL-10 was reduced by 300 nM DEX and by 150 and 300 nM CORT (P<0.05). ConA increased relative abundance of MIF mRNA (P<0.001), but no steroid treatment affected MIF mRNA. In Experiment 3, steroid additions were delayed by 24 h after ConA, and cytokine concentrations evaluated 48 h later. Again, separate cultures were used for determination of effect of treatments on MIF mRNA. None of the steroid treatments affected IFNgamma, but 300 nM DEX reduced IL-10 (P<0.05). All of the CORT treatments (75-300 nM) reduced MIF mRNA (P<0.05), whereas DEX did not affect MIF mRNA in this experiment. The current experiments suggest that both DEX and high physiological concentrations of CORT can suppress both type 1 and type 2-like cytokines in cultured pig splenocytes. But, IL-10 was generally more sensitive to CORT suppression with increased time in culture than was IFNgamma. In addition, MIF mRNA could be suppressed by delayed addition of CORT to porcine splenocytes. Taken together, the data do not support the hypothesis that CORT directs the cytokine milieu toward a type 2 bias in cultured pig splenocytes.  相似文献   
135.
A 6-year-old male red squirrel (Sciurus vulgaris orientis) developed bilateral tumors of upper and lower eyelids. The tumors in the left lid recurred despite surgical removal. Necropsy revealed metastasis to the lung. The neoplastic cells were epithelioid and highly pleomorphic, and only a few cells contained melanin granules. Occasionally melanoma cells were immunoreactive for S100, neuron-specific enolase and vimentin, and a small number of cells for cytokeratin. Ultrastructurally, the presence of premelanosomes was confirmed in the cytoplasm. Possible presence of cytokeratin-positive neoplastic melanocytes should be taken into account when differentiating a nonpigmented epithelioid melanoma from other tumors such as anaplastic carcinomas.  相似文献   
136.
A 14-year-old female cougar died from gastroduodenal adenocarcinomas and rectal adenoma. At necropsy, polypoid tumor masses of various sizes were scattered on the mucosal surfaces of the stomach, duodenum, and rectum. Histologically, the gastric tumor was diagnosed as an intestinal type adenocarcinoma and the tumor cells metastasized to the mesenteric lymph nodes, spleen, and lung. Helicobacter-like organisms were detected in the lumina lined by foveolar epithelium. In the duodenum, the carcinoma cells were localized in the limina propria and many of them were intensely positive for proliferating cell nuclear antigen (PCNA). In contrast, the rectal adenoma had a lower number of PCNA-positive cells. In the rectum, chronic inflammation with numerous spirochetes was also noted. These results indicated that the occurrence of the gastrointestinal tumors might be associated with the bacterial infection described above.  相似文献   
137.
The prevalence of blood parasites was investigated in 701 Japanese wild birds for 13 years from January, 1988 to March, 2001. Most of the injured or sick birds were caught in the suburbs of Kobe City, Hyogo Prefecture and brought to the zoo for clinical care. Among all the birds examined, 10.6% were infected with hematozoa belonging to three genera as Plasmodium (1.7% of the samples), Haemoproteus (5.1% of the samples) and Leucocytozoon (4.6% of the samples), and two birds (0.29% of the samples), a Japanese grosbeak (Coccothraustes personatus) and a dusky thrush (Turdus naumanni), were infected with microfilariae. Mixed infection with Leucocytozoon sp. and Haemoproteus sp. was observed in 6 individuals of 4 species and that with Leucocytozoon sp. and microfilariae was observed in 2 individuals of 2 species of bird. Relatively high positive rates were 75%(3/4) in the scops owl (Otus scops), 71.4% (10/14) in the ural owl (Strix uralensis), 57.7% (15/26) in the jungle crow (Corvus macrorhynchos), 57.1% (4/7) in the black-tailed gull (Larus crassirostris), 55.6% (5/9) in the brown hawk owl (Ninox scutulata), 41% (16/39) in the carrion crow (Corvus corone) and 24.1% (7/29) in the night heron (Nycticorax nicticorax).  相似文献   
138.
Adverse reactions to vaccines were examined in 311 canine cases reported to the Ministry of Agriculture, Forestry and Fisheries in Japan during the period of 6 years from April of 1994 to March of 2000, and classified according to their clinical symptoms. There were 27 cases of adverse reactions to rabies virus vaccines. Gastrointestinal symptoms were the most frequently observed (26%), followed by respiratory and/or cardiovascular symptoms (22%) and dermatologic symptoms (11%). There were 284 cases of adverse reactions to non-rabies monovalent vaccines and mixed vaccines. Dermatologic symptoms were the most frequently observed (53%), followed by gastrointestinal symptoms (16%) and respiratory and/or cardiovascular symptoms (14%). Of the total 311 cases, 11 (3.5%) died of adverse reactions to vaccines.  相似文献   
139.
A 37-day-old male Japanese black calf showing marked salivation and leucocytosis died and was examined the tissues histologically. Histological lesions were characterized by severe focal necrotic glossitis on the ventral side of the root of the tongue. Immunohistochemically, Fusobacterium necrophorum subsp. necrophorum antigen was detected in the necrotic tissues and its distribution corresponded to that of the gram-negative, nonsporeforming, long filamentous organisms. Ultrastructural similarities between the organism and F. necrophorum subsp. necrophorum, but not subsp. funduliforme were observed. These findings clearly demonstrated that the fatal necrotic glossitis was caused by F. necrophorum subsp. necrophorum. This is the first report of bovine fatal necrotizing glossitis with leucocytosis caused by F. necrophorum subsp. necrophorum infection, and this organism may be an important fatal pathogen in calves with glossal lesions.  相似文献   
140.
Partial sequences of the 18S rRNA gene (625 bp) from a Hepatozoon detected in two canine hepatozoonosis cases, one clinical and one subclinical, in Japan were analyzed. Both sequences were identical to each other and they were closely related to the Hepatozoon canis strain found in Israel with 99% (617/625) nucleotide identity. Both Hepatozoon americanum and Hepatozoon catasbianae were distantly related to the Japanese Hepatozoon with 94% (586/625) and 91% (566/625) identities, respectively. In a phylogenetic tree, the Japanese Hepatozoon was most closely related to H. canis from Israel but was significantly different than H. americanum and H. catasbianae. These results suggest that the Hepatozoon detected in the Japanese dogs might be a strain variant of H. canis, but is apparently a different species than H. americanum.  相似文献   
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