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41.
The NOTCH ligand, JAG2, was found to be overexpressed in malignant plasma cells from multiple myeloma (MM) patients and cell lines but not in nonmalignant plasma cells from tonsils, bone marrow from healthy individuals, or patients with other malignancies. In addition, JAG2 overexpression was detected in 5 of 5 patients with monoclonal gammopathy of undetermined significance (MGUS), an early phase of myeloma disease progression. This overexpression appears to be a consequence of hypomethylation of the JAG2 promoter in malignant plasma cells. An in vitro coculture assay was used to demonstrate that JAG2 induced the secretion of interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), and insulin-like growth factor-1 (IGF-1) in stromal cells. Further, the induction of IL-6 secretion was blocked in vitro by interference with anti-Notch-1 monoclonal antibodies raised against the binding sequence of Notch-1 with JAG2. Taken together, these results indicate that JAG2 overexpression may be an early event in the pathogenesis of multiple myeloma involving IL-6 production.  相似文献   
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BACKGROUND & OBJECTIVES: Vector control will for sometime remain a primary weapon in the war against vector borne diseases. Malaria is of paramount importance in this with its associated high morbidity and mortality especially in sub-Saharan Africa. This study on generational mortality associated factors in Anopheles mosquitoes life-table analysis was designed to investigate the fecundity, levels of mortality and mortality associated factors at the aquatic stages of anopheline malaria vectors. METHODS: Mortality associated factors were investigated at the eggs, I and II instar larval, III and IV instar larval and pupal stages of two anopheline species--Anopheles pseudopunctipennis (Theobald) and An. gambiae life-cycles in screen cages. Adult male and female mosquitoes were membrane filter-fed and algae in culture medium formed the bulk of food substances for the larval stage. Environmental temperature of culture media, pH and some associated physio-chemical factors were also determined. RESULTS: Results showed significant mortality rates at various aquatic stages. Infertility, cannibalism and environmental factors were the major factors responsible for mortality at the egg, larval and pupal stages respectively. INTERPRETATION & CONCLUSION: The aquatic stages of Anopheles mosquito mortality factor K and the mortality factors at the various stages investigated k1, k2, k3 and k4 are discussed. Our recommendations include further studies on the possible genetic modification of predacious An. pseudopunctipennis larvae and/or its modification for the production of sterile/infertile eggs as possible alternatives in the reduction and control of anopheline malaria burden.  相似文献   
44.

Ethnopharmacological relevance

Traditional healers in Nigeria use a combination of decoctions from green leafy vegetables in their blood glucose (BG) lowering recipes. Three plants Vernonia amygdalina (Del.) (VA), Gongronema latifolium (Benth.) (GL) and Occimum gratissimum (Linn.) (OG) are found consistently in such recipes. Whereas the anti-diabetic properties of extracts of these plants have been reported in animal models, little is known about the effects of their aqueous decoctions (singly or in combinations) on oral glucose tolerance (OGT) in humans.

Materials and methods

Twenty seven subjects were recruited and (on separate days) were given 150 mL of water, VA, GL and OG decoctions or blends of the decoctions to drink 45 min before a 2-h OGTT. Their OGTT curves were plotted and areas under the curves (AUCs) calculated.

Results

The results show that each of the three decoctions neither altered the peak time of the OGTT nor significantly (P>0.05) reduced the BG concentrations (BGCs) at any time point on the test curves relative to the baseline. VA, OG and GL gave 0.4, 0.2 and 2.8% reductions in the AUCs, respectively, relative to the baseline. Blending GL and VA did not improve the results. However, a decoction containing the three vegetables in equal proportions significantly reduced the BGCs at 90 (96.8±9.5 vs. 107.1±10.2 mg/dL; P=0.041) and 120 (92.8±14.3 vs. 102.5±12.1 mg/dL; P=0.037) minutes relative to the baseline, and gave better reductions in the AUCs (4.1%).

Conclusion

The decoction containing the three vegetables was found to be superior in activity to any 1, or blends of only 2, of the 3 decoctions. This is a case of positive synergism, and justifies the use of these plants in ethnopharmacological BG lowering recipes.  相似文献   
45.
ObjectiveTo investigate the calcium and phosphorus contents of four domestic animals used as sources of meat in Nigeria.MethodsThe calcium contents of the body parts of the animals were determined using atomic absorption spectrometer. Their phosphorus contents were determined colorimetrically using the molybdenum blue method.ResultsThe calcium and phosphorus contents were significantly higher in the bone samples than in the other animal parts investigated (P<0.05). The calcium contents of all the edible parts were higher in chicken than in the other animals. High calcium and phosphorus contents were detected in the faeces of chicken and goat, and that of cattle and goat, respectively. Low calcium and phosphorus contents were detected in the urine samples. Calcium: phosphorus ratios calculated for the bones of chicken, cattle and goat were satisfactory.ConclusionsIn conclusion, calcium and phosphorus contents of the animal parts vary significantly and their relative contents may be related to the animal's diet. Chicken parts may be the preferred dietary source of these minerals. This study highlights the need for routine investigation of the mineral contents of food, which is necessary for proper nutritional guidelines.  相似文献   
46.
Neurocysticercosis appears to be on the rise in the United States, based on immigration patterns and published cases series, including reports of domestic acquisition. We used a collaborative network of U.S. emergency departments to characterize the epidemiology of neurocysticercosis in seizure patients. Data were collected prospectively at 11 university-affiliated, geographically diverse, urban U.S. emergency departments from July 1996 to September 1998. Patients with a seizure who underwent neuroimaging were included. Of the 1,801 patients enrolled in the study, 38 (2.1%) had seizures attributable to neurocysticercosis. The disease was detected in 9 of the 11 sites and was associated with Hispanic ethnicity, immigrant status, and exposure to areas where neurocysticercosis is endemic. This disease appears to be widely distributed and highly prevalent in certain populations (e.g., Hispanic patients) and areas (e.g., Southwest).  相似文献   
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48.

Background  

Efficient delivery strategies for health interventions are essential for high and sustainable coverage. We report impact of a change in programmatic delivery strategy from routine delivery through the Expanded Programme on Immunization (EPI+) approach to twice-yearly mass distribution campaigns on coverage of vitamin A supplementation in Tanzania  相似文献   
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This is by far the largest study of its kind to date, and further suggests that AIB1 does not play a substantial role in modifying the phenotype of BRCA1 and BRCA2 carriers. The AIB1 gene encodes the AIB1/SRC-3 steroid hormone receptor coactivator, and amplification of the gene and/or protein occurs in breast and ovarian tumors. A CAG/CAA repeat length polymorphism encodes a stretch of 17 to 29 glutamines in the HR-interacting carboxyl-terminal region of the protein which is somatically unstable in tumor tissues and cell lines. There is conflicting evidence regarding the role of this polymorphism as a modifier of breast cancer risk in BRCA1 and BRCA2 carriers. To further evaluate the evidence for an association between AIB1 glutamine repeat length and breast cancer risk in BRCA1 and BRCA2 mutation carriers, we have genotyped this polymorphism in 1,090 BRCA1 and 661 BRCA2 mutation carriers from Australia, Europe, and North America. There was no evidence for an increased risk associated with AIB1 glutamine repeat length. Given the large sample size, with more than adequate power to detect previously reported effects, we conclude that the AIB1 glutamine repeat does not substantially modify risk of breast cancer in BRCA1 and BRCA2 mutation carriers.  相似文献   
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