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1.
Dolphins in a captive environment are exposed to various kinds of stresses. Handling and transportation are stressful events for terrestrial mammals, and such stress may affect immune system function and increase susceptibility to infectious diseases. The same phenomenon could occur in dolphins, however, few studies have reported this in dolphins. The objective of this study was to evaluate the relationship between stress and polymorphonuclear (PMN) cell function of dolphins during transportation. Four bottlenose dolphins (Tursiops truncatus) were transported for 6 hr by truck. Serum cortisol levels, leukograms, phagocytosis, and superoxide production of PMN cells were evaluated during handling and transportation compared to resting values. The mean serum cortisol level was significantly increased during handling and transportation (p<0.05) when compared with the resting values. White blood cell (WBC) counts, eosinophil counts, phagocytosis, and superoxide production of PMN cells during handling and transportation stages decreased significantly in comparison with the resting stage (p<0.05). The concentration of serum cortisol was significantly correlated with the results of the WBC counts, eosinophil counts, superoxide production, and phagocytosis (p<0.01, p<0.05, p<0.05, and p<0.001, respectively). The present results indicate that handling and transportation are stressful events for dolphins and could affect their PMN cell functions, thereby leading to the impairment of the immune system.  相似文献   
2.
Porcine bioprosthetic valves cross-linked with glutaraldehyde and polyepoxy compound were newly developed for mitral valve replacement (MVR) in dogs. Five beagle dogs were performed a left thoracotomy and underwent MVR using the porcine bioprosthetic valves during cardiopulmonary bypass (CPB). A vein catheter inserted into right atrium and a vent catheter inserted into the right ventricle to drain. The hemodynamic conditions of CPB were excellent during surgery. The left atrial pressure was measured before and after MVR; there was no significant difference and it was normal. Thrombosis and the prosthetic valve regurgitation were not observed one week after MVR. Pressure half time (PHT) prolonged significantly (P<0.05) from 31.40 +/- 4.0 msec presurgery to 99.20 +/- 19.4 msec at seven days after MVR, although it indicated the normal range as the bioprosthetic valve. The symptom of the prosthetic valve failure was not observed. This study indicated that the MVR using porcine bioprosthetic valves under CPB might have been effective in dogs as a short-term evaluation.  相似文献   
3.
To clarify the contribution of autologous transplantation of mesenchymal stromal cells (MSCs), an atelocollagen gel containing or not containing fluorescently-labeled canine MSCs was transplanted into an osteochondral defect which did not repair spontaneously and the histological repair of the defect was compared. Although an early repair of the cartilage was not observed in either defect, the reproduction of subchondral bone was remarkable in the MSCs-implanted defect. Moreover, in 2 weeks after operation, the implanted MSCs were located in the deeper regions of the defect, suggesting the differentiation of osteoblasts. There was a possibility that the movement of the implanted MSCs was due to an increase in intra-articular pressure from postoperative inflammation.  相似文献   
4.
Juvenile green abalone Haliotis rufescens were grown under laboratory conditions at 21±1 °C and fed formulated diets consisting of different protein:energy ratios (mg protein/kcal), 62, 74, 85, 100, 108, for 60 days. The level of crude protein ranged from approximately 26% to 44% while the energy content remained constant at about 4.1 kcal g−1. Growth ranged from 3.63 to 12.33 mg day−1. The growth of abalone fed the 100 and 108 diets was significantly greater than that of each of the other diets. Protein efficiency ratio increased as the dietary protein content increased except for the T108 diet (44% crude protein). Abalone apparently consume food to satisfy an energy requirement. Caloric expenditure due to metabolism was estimated for abalone fed diets with protein ratios of 62, 85, 100. Energy loss due to respiration did not vary appreciably among abalone fed the different diets. The proportional distribution of dietary energy into fecal, digestible, growth, and metabolic energy was estimated for abalone fed these diets. Apparent dry matter digestibility was among the lowest for abalone fed the 100 P:E diet, but growth of abalone fed this diet was significantly higher than that of each of the other treatments except the 108 diet. Unexplained energy loss to achieve balance ranged from 7% to 28.5%, some of which is probably due to differential mucus and ammonia production. Results suggest a potential for the reduction of both dietary protein and lipid without causing any adverse effects on the growth response.  相似文献   
5.
The pharmacokinetics of oxolinic acid and oxytetracycline were examined in kuruma shrimp (Penaeus japonicus) after intra-sinus (10 and 25 mg/kg, respectively) and oral (50 mg/kg) administration. The shrimp were kept in tanks with recirculated artificial seawater at a salinity of 22–23 ppt. The water temperature was maintained at 25±0.6 °C. The hemolymph concentrations of both drugs after intra-sinus dosing were best described by a two-compartment open model. The distribution and elimination half-lives (t1/2 and t1/2β) were found to be 0.59 and 33.2 h for oxolinic acid and 0.45 and 24.7 h for oxytetracycline, respectively. The apparent volume of distribution at a steady state (Vss) and total body clearance (CLb) were estimated to be 1309 ml/kg and 28.8 ml/kg/h for oxolinic acid and 748 ml/kg and 22.7 ml/kg/h, respectively. The hemolymph concentration–time curves after oral administration did not fit by the nonlinear least squares method using one- and two-compartment model with first-order absorption in either of the drugs. The peak hemolymph concentration (Cmax), the time to peak hemolymph concentration (tmax) and the elimination half-life were found to be 17.8 μg/ml, 7 h and 34.3 h for oxolinic acid and 24.3 μg/ml, 10 h and 33.6 h for oxytetracycline, respectively. The bioavailability (F) after oral administration was 32.9% for oxolinic acid and 43.2% for oxytetracycline. The hemolymph protein binding in vivo was determined to be 36.7±8.5% for oxolinic acid and 22.9±4.8% for oxytetracycline.  相似文献   
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A 10-year-old, female shih tzu was diagnosed as having myelodysplastic syndrome (MDS) based on the presence of a nonregenerative anemia, dysplastic changes in the three hematopoietic cell lines, a normal to hypercellular bone marrow, and less than 30% blast cells of all nucleated cells in the bone marrow. Low-dose aclarubicin, a differentiation-induction therapy for MDS and atypical leukemias in humans, was administered. Hematological improvement was observed, and the dog lived for 809 days after the first presentation.  相似文献   
9.
We performed a pathologic examination of the brains of three dogs in an epileptic beagle colony. Histologically, all the cases had diffuse astrocytosis in the cerebral cortex and basal ganglia as well as the hippocampus, whereas they showed acute nerve cell change in the hippocampus and some other areas of the cerebrum. One of these animals showed laminar myelin pallor associated with the presence of many vacuoles in the IV to VI layers of the bilateral motor cortices. Most of the vacuoles contained fine granules stained with luxol-fast-blue stain. Ultrastructural examination revealed that some oligodendrocytes and perineuronal satellite oligodendrocytes in the bilateral cerebral motor cortices of the two affected dogs had many vacuoles surrounded by myelin-like lamellar structures. These findings suggest a possibility that astrocytosis in the cerebrum and vacuolar degeneration of oligodendrocytes in the cerebral motor cortex may be, at least in part, related to the occurrence or development of seizures.  相似文献   
10.
In vitro cell culture is a convenient tool for studying cellular mechanisms. In the present study, production of matrix-metalloproteinases (MMPs) in bovine endometrial (containing both epithelial and stromal cells) monolayer cells was examined. Blastocysts attached to the endometrial cells in a monolayer culture were examined for their effects on MMP-2 production. Initial attachment of blastocysts to the monolayer inhibited MMP-2 production by endometrial cells. But once trophoblast cells began to migrate into the endometrial cell layer, MMP-2 production increased, and at the same time MMP-9 production also became evident in the medium. In order to understand how blastocysts affected MMP-2 production, we examined the effect of progesterone, estradiol, insulin-like growth factors (IGFs), tumor necrosis factors (TNFs), and interferon-tau (IFN-tau) supplementation. It was IFN-tau that inhibited the production of MMP-2. In addition, progesterone at a lower dose appeared to inhibit MMP-2 production. Both TNF-alpha and TNF-beta strongly stimulated the production of MMP-2 and MMP-9, whereas IGFs had no effect. Based on these findings, it appears that conceptus has the capacity to inhibit MMP activity.  相似文献   
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