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81.
Inadequate milk curd formation in the abomasum of newborn calves causes malnutrition and diarrhea. In order to define the factors of inadequate curd formation, we compared the curd forming ability among 9 kinds of milk replacers, bulk milk (raw milk), and skim milk both in vitro and in vivo . When rennet was added, the raw milk and one milk replacer formed firm curds. The rest of the milk replacers and skim milk did not form any curd. When a solution of HCl was added, raw milk, three milk replacers and skim milk formed the curd at pH 4.5, but the other milk replacers did not. When HCl was added following the rennet, raw milk, one milk replacer and skim milk formed the curd. In vivo , raw milk, two milk replacers and skim milk showed good curd formation whereas the other milk replacers showed poor curd formation inside the abomasums of the calves. This study showed that most of the milk replacers sold in Japan could not form the curd with rennet.  相似文献   
82.
Although our previous report demonstrated that adiponectin and AdipoR1 gene expressions changed among different lactation stages in the bovine mammary gland, its in vivo kinetics remain unclear in ruminant animals. In this study, we investigated the changes in circulating concentrations of adiponectin, as well as other metabolic hormones and metabolites, (i) during the periparturient period and (ii) among different lactation stages, in Holstein dairy cows. In experiment 1, serum adiponectin concentrations increased after parturition. Serum insulin concentrations were lower in the postpartum than prepartum period, whereas serum growth hormone (GH) concentrations increased in the postpartum period. Serum nonesterified fatty acids (NEFA) levels were increased during the postpartum period and were dependent on the parity. In experiment 2, there was no significant difference in plasma adiponectin concentrations among lactational stages. Plasma insulin concentrations tended to be lower in early lactation while plasma GH levels tended to be higher. Plasma NEFA concentrations were significantly lower in mid‐ and late‐lactation stages than non‐lactation stages. These findings indicate that elevation of serum adiponectin might be involved in energy metabolism just around parturition, and might exert its action through regulation of receptor expression levels in target tissues in each lactational stage in Holstein dairy cows.  相似文献   
83.
Several studies have shown a relationship between depression and animal protein intake. To evaluate whether the difference of dietary chicken protein levels induces an antidepressant‐like effect and potentiates acute antidepressant effects, three levels of dietary chicken protein were used as the representative animal protein with imipramine used as the antidepressant. In addition, the effects of dietary chicken protein on brain metabolism were evaluated. Open field test (OFT) and forced swimming test (FST) were conducted on the 27th and 28th days, respectively. OFT and FST were not influenced by both imipramine and dietary protein levels. However, characteristic effects of imipramine treatment on brain monoamine metabolism were observed in the cerebral cortex and hypothalamus. In addition, dietary protein significantly increased taurine and L‐ornithine levels even though these amino acids were not contained in the diets. In conclusion, the metabolism of several amino acids in the plasma and brain were altered by dietary chicken protein.  相似文献   
84.
Several amino acids have effects on mental function, including sedative, antidepressant‐like and anxiolytic‐like effects. However, the influence of integrated amino acid nutrition as protein constituents on mental function remains unclear. Therefore, the purpose of the present study was to compare the influence of chicken, pork and beef protein extracts on brain monoamine metabolism in mice. Changes in monoamine levels and their turnover rates in the brain were induced by different protein sources. In particular, chicken protein group showed the highest norepinephrine levels in the hippocampus and hypothalamus, and beef protein extract caused an activation of the serotonergic system in the hypothalamus, although there were no significant differences in amino acid compositions of these protein extracts. Therefore, it was revealed that amino acid compositions in dietary protein did not induce alteration in monoamine metabolism. However, there were differences in small molecular peptides, such as creatine, carnosine and anserine levels in animal protein extracts. In conclusion, monoamine metabolism was altered by dietary protein sources. However, it was indicated that the alteration in monoamine metabolism may be independent from amino acid compositions in dietary protein. In addition, alteration in monoamine metabolism depending on the dietary protein sources may be induced by small molecular peptides.  相似文献   
85.
Two pony mares were immunized against recombinant porcine inhibin alpha subunit three times with 39 day intervals. Clinical findings and endocrinological changes before immunization were taken as the control. The first significant rise in the anti-inhibin titre (P<0.05) in the circulation was found 27 days after the first injection. Maximum binding activity was reached by the 12th day after the second booster dose. The number of small, medium and large sized follicles had increased significantly compared to before immunization (11.75 +/- 4.30, 2.75 +/- 0.69 and 2.51 +/- 0.63 vs 6.50 +/- 1.43, 1.83 +/- 0.44 and 1.33 +/- 0.38, respectively), but the ovulation rate remained unchanged after immunization. The average plasma concentration of FSH and estradiol-17beta during the estrous cycle increased significantly (P<0.05) after immunization. These results suggest that immunization against inhibin is a useful tool to increase the number of ovarian follicles during the estrous cycle of pony mares. Moreover, the present study supported the concept that inhibin plays a major role in the control of follicular growth through its inhibitory effect on FSH secretion synergistically with steroid hormones.  相似文献   
86.
Hepatocyte growth factor (HGF) is a pleiotropic cytokine that stimulates a wide array of cellular targets, including hepatocytes and other epithelial cells, melanocytes, endothelial and hematopoietic cells. We have cloned a different form of cDNA, with a deletion of 15 base pairs predicted to result in the loss of 5 amino acids from the first kringle domain. To investigate the biological activity, original and deleted variant of feline HGF cDNAs were transiently expressed in COS-7 cells. Both recombinant feline HGFs showed almost the same dose-response curves in the stimulation of the growth of BNL CL.2 cells (a mouse hepatocyte cell line) and scatter activity of Madin-Darby canine kidney (MDCK) cells. The findings reported here suggest that the deleted variant of feline HGF has almost the same biological activity as the original in terms of the proliferation and scatter activity.  相似文献   
87.
A new valved conduit was developed using a canine aortic valve. The bioprosthetic valve was fixed with glutaraldehyde and epoxy compound (Denacol-EX313/810). A vascular graft composed of ultra-fine polyester fiber (10 mm in diameter, 200 mm in length) was used. Four dogs underwent apico-aortic valved conduit (AAVC) implantation and aortic banding (bypass group, BG), while another 4 dogs underwent aortic banding without AAVC implantation (control group, CG). Cardiac catheterization and angiocardiography were performed for assessment of hemodynamics 2 weeks and 6 months after surgery. Left ventricular systolic pressure, left ventricular end-diastolic pressure and the left ventricular-aortic pressure gradient differed significantly (P<0.01) between the BG and CG dogs. Left ventricular angiocardiography showed patency of the valved conduit in all the BG dogs. Echocardiography was performed before and 2, 4 and 6 months after surgery, and showed that while pressure overload caused concentric myocardial hypertrophy in the CG dogs, the left ventricle dilated eccentrically in the BG dogs. Furthermore, relief of left ventricular pressure overload by AAVC was maintained.  相似文献   
88.
To investigate the effect of hoof trimming before the dry period, the hooves of 10 cows (trimmed group) were trimmed at 79.6 +/- 8.6 days before parturition and the hooves of 52 cows were left untrimmed (control group). Blood biochemistry and hormone concentrations were investigated for 6 cows from each group. The daily milk yield after parturition in the trimmed group tended to be higher than that of the control group. Between 0 and 30 days after parturition, the levels of non-esterified fatty acids were significantly lower stet, and the plasma glucose and glucose disposal rates were significantly higher in the trimmed group. The plasma cortisol concentration was stable before and after parturition in the trimmed group. Hoof trimming before the dry period appears to reduce stress and maintain the nutritional conditions of perinatal dairy cows.  相似文献   
89.
Device-associated infections are serious complications, and their prevention is an issue of considerable importance. Since biofilms are responsible for these refractory infections, effective methods to inhibit biofilm formation are required. In this investigation, stainless steel plates with and without 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer, i.e., poly (MPC-co-n-butyl methacrylate) (PMB) coating, were incubated in a medium containing bacteria. In the course of incubation, half of the specimens received antibiotics. The specimens were stained for nucleic acid and polysaccharides, and then examined with a confocal laser scanning microscope. The numbers of bacteria on the specimen surfaces were evaluated by an ATP assay. On the surfaces of the specimens without PMB coating, the formation of a biofilm enveloping bacteria was confirmed. The addition of antibiotics did not effectively decrease the number of bacteria. On the other hand, on the surfaces of the specimens with PMB coating, no biofilm formation was observed, and the number of bacteria was significantly decreased. The addition of potent antibiotics further decreased the number of bacteria by 1/100 to 1/1000 times. The PMB coating combined with the validated use of antibiotics might provide a method for the simultaneous achievement of biocompatible surfaces of devices and the prevention of device-associated infections.  相似文献   
90.
A 4-month-old male French Bulldog weighing 5.0 kg (11 lb) was referred for a heart murmur. A grade 3/6 systolic murmur was detected at the left heart base and a grade 4/6 systolic murmur was detected at the right heart base. By use of color-flow Doppler ultrasonography and cardiac catheterization, a diagnosis of supracristal ventricular septal defect (VSD) with accompanying aortic regurgitation was made. Percutaneous transcatheter coil embolization was used to close the VSD. Because residual shunt was detected via echocardiography after coil implantation, the residual shunt was followed periodically via echocardiography to detect spontaneous closure of the VSD. Volume overload in the left ventricle was detected in the dog 131 days after admission. Additional coils were placed 137 days after admission. Hemolysis resulting in hemoglobinuria was detected, but this complication was mild. In the dog of this report, results of coil occlusion for correction of VSD were promising. Thus, coil occlusion should be considered as an alternative treatment for VSD in dogs.  相似文献   
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