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991.
Medical doctors, who practice interventional cardiology, receive a noticeable radiation dose. In this study, we measured the radiation dose to 9 cardiologists during 144 procedures (72 coronary angiographies and 70 percutaneus translumined coronary angioplasties) in two Greek hospitals. Absorbed doses were measured with TLD placed underneath and over the lead apron at the thyroid protective collar. Based on these measurements, the effective dose was calculated using the Niklason method. In addition, dose area product (DAP) was registered. The effective doses, E, were normalised to the total DAP measured in each procedure, producing the E/DAP index. The mean effective dose values were found to be in the range of 1.2-2.7 microSv while the mean E/DAP values are in the range of 0.010-0.035 microSv/Gycm2. The dependence of dose to the X-ray equipment, the exposure parameters and the technique of the cardiologist were examined. Taking under consideration the laboratories' annual workload, the maximum annual dose was estimated to be 1.9 and 2.8 mSv in the two hospitals.  相似文献   
992.
Relationship between floor type and risk of ACL injury in team handball   总被引:1,自引:0,他引:1  
The purpose of this study was to compare the ACL injury rate between two different floor types - wooden floors (parquet, generally having lower friction) and artificial floors (generally having higher friction). ACL injuries have been recorded prospectively from the three top divisions for men and women in Norwegian team handball during seven seasons (1989-2000). A total of 174 ACL injuries have been recorded, and of these 53 occurred in regular league games. The floor types for all regular games from the same seasons have been determined retrospectively based on match schedules. The matches were divided into two groups: those played on wooden floors and those played on artificial floors. A total of nine injuries occurred among men (incidence: 0.24+/-0.09 injuries per 1000 player hours) and 44 among women (0.77+/-0.04 injuries 1000 h(-1); OR vs. men: 3.21 (1.56-6.58); P=0.001). Among men, four injuries occurred on wooden floors (0.32+/-0.13 injuries 1000 h(-1)) and five injuries occurred on artificial floors (0.20+/-0.12 injuries 1000 h(-1); OR vs. wooden floors: 0.63 (0.17-2.37); ns). Among women, eight injuries occurred on wooden floors (0.41+/-0.09 injuries 1000 h(-1); OR vs. men: 1.29 (0.39-4.28); ns) and 36 on artificial floors (0.96+/-0.04 injuries 1000 h(-1); OR vs. wooden floors: 2.35 (1.09-5.07); P=0.03; OR vs. men: 4.77 (1.87-12.18); P=0.001). These results indicate that the risk of ACL injury for women is higher on artificial floors than on wooden floors.  相似文献   
993.
The gastric peptide ghrelin augments and the adipocyte-derived hormone leptin reduces appetite and food intake. In the central nervous system, insulin directly decreases hunger sensation but could also act indirectly by modulating ghrelin and leptin secretion. This study examines dose-dependent effects of insulin on plasma ghrelin and leptin concentrations during hyperinsulinemic (1, 2, and 4 mU x kg(-1) x min(-1))-euglycemic clamp tests in six nondiabetic (control subjects) and six type 2 diabetic patients. Type 2 diabetic patients were studied before and after prolonged (12-h and 67-h) variable intravenous insulin treatment aiming at near-normoglycemia (115 +/- 4 mg/dl). Nondiabetic subjects were also studied during saline infusion, which did not affect ghrelin but decreased leptin by 19 +/- 6% (P < 0.03). In control subjects, plasma ghrelin decreased at all clamp steps (-17 +/- 1, -27 +/- 6, and -33 +/- 4%, respectively; P < 0.006 vs. baseline), whereas leptin increased by 35 +/- 11% (P < 0.05). In type 2 diabetic patients without insulin treatment, ghrelin decreased by 18 +/- 7% (P < 0.05) only after 4 mU x kg(-1) x min(-1) insulin infusion and leptin increased by 19 +/- 6% (P < 0.05). After prolonged insulin treatment and near-normoglycemia, ghrelin and leptin remained unchanged in type 2 diabetic patients during the clamps. In conclusion, insulin reduces plasma ghrelin in nondiabetic patients and, to a lesser extent, in type 2 diabetic patients before insulin therapy. These findings indicate an indirect effect of insulin via ghrelin on the suppression of hunger sensation and appetite.  相似文献   
994.
995.
BACKGROUND: The authors report on their experience with food-induced angioedema in tacrolimus-immunosuppressed pediatric liver recipients. METHODS: Among 121 children treated with tacrolimus after liver transplantation, those who presented with angioedema are reported. RESULTS: Twelve children (10%) experienced angioedema related to food allergy while on tacrolimus. Mean ages at transplantation and angioedema were 1.3 years and 3.75 years, respectively. Angioedema occurred within a mean of 28 months from onset of tacrolimus. Eleven children experienced two or more angioedema attacks without consequences. One child presented with anaphylactic shock that caused postischemic cerebral damage. Besides eviction of food allergens, eight children were switched from tacrolimus to cyclosporine, whereas tacrolimus dosage was decreased in four. Reintroduction of food allergens was successfully performed only in those who were switched to cyclosporine. CONCLUSION: A causal relationship between tacrolimus and the occurrence of food-induced angioedema is suggested. The switch from tacrolimus to cyclosporine should be considered.  相似文献   
996.
The literature make it clear that lung cancer in women differs from that in men in several specific aspects. We conducted a retrospective study of the 967 consecutive recorded patients (696 men and 91 women after exclusions) diagnosed with small cell lung cancers (SCLC) between 1981 and 1994 in the Bas-Rhin population-based cancer registry to determine if such particularities could be observed in SCLC. Data included demographic and social characteristics, medical and smoking history, management (diagnosis and treatment), hospitalisation and survival. The end point for survival was 31 December 1998. Women were more frequently single, divorced, or widowed (P=0.007) and lived more often in urban areas (places with more than 10,000 inhabitants) (P=0.017). They differed significantly from men in their tobacco exposure (P=0.0001) and non-smoking rates (P=0.0003) but not in clinical presentation, except for more frequently elevated LDH levels (P=0.02). Bone marrow biopsies were more often performed in men (P=0.004), but management was otherwise comparable. The mean number of hospitalisations (for any reason) was comparable in both sexes but women tended to remain hospitalised longer (P=0.057). Overall survival did not differ, but women older than 70 years died sooner than their male counterparts (P=0.026). Our study confirms that some of gender differences reported in the lung cancer literature exist in SCLC. Sex-related differences in LDH levels have not previously been reported, to our knowledge. North American and European data concerning survival among women and men are discordant. Whether these gender differences are related to a real difference between the sexes or simply to differential exposure to carcinogens remains to be determined.  相似文献   
997.
We investigated the influence of estrogenic and antiestrogenic treatment on proteolytic activity--especially on MMP-2 and MMP-13--in the RUCA-I transplantable endometrial tumor model. Morphological studies demonstrate that RUCA-I cells are forming highly differentiated gland-like structures by remodelling and invading the underlying ECM. Estrogens upregulate the mRNA levels of MMP-2 and MMP-13 in the rat uterus. Treatment with the pure antiestrogen ICI 182,780 results in the downregulation of MMP-2 and MMP-13 mRNA. The same regulation for MMP-13 mRNA is found in vitro in RUCA-I cells. In contrast, in the transplantation tumor, the mRNA level of MMP-13 is repressed by estrogens and induced by ICI 182,780. MMP-2 mRNA is not regulated by hormones in the transplantation tumor and in RUCA-I cells. The divergent regulation suggests a varying influence of cell-cell-, cell-extracellular matrix interactions and soluble factors.  相似文献   
998.
Previously we have shown that the matrix metalloproteinase matrilysin (MMP-7) is overexpressed in human prostate cancers compared with normal epithelium. However, the mechanism for this overexpression is not understood. Human prostate fibroblasts have been shown to express certain fibroblast growth factors (FGFs), including FGF-1. Evidence from our laboratory and others has indicated that FGFs can regulate the expression of certain matrix metalloproteinases, including matrilysin. The goal of this study was to determine whether pharmacological inhibition of FGFR signaling would alter LNCaP tumor growth as well as expression of promatrilysin when LNCaP cells were co-injected subcutaneously with human prostate fibroblasts into athymic nude mice. For these inhibitor studies, AG1-X2 beads were coated with the pharmacological FGFR inhibitor SU5402 and were co-injected along with LNCaP and human prostate fibroblast cells (PF). Mice injected with LNCaP/PF and LNCaP/PF/beads alone demonstrated significant tumor growth, whereas mice injected with LNCaP/PF/SU5402-coated beads showed a significant decrease in tumor volume and weight. Immunohistochemical analysis showed that significant promatrilysin expression in tumors was inhibited by the FGFR inhibitor SU5402. Serum prostate-specific antigen (PSA) and promatrilysin levels were measured by enzyme-linked immunosorbent assay. The mice injected with LNCaP/PF and LNCaP/PF/beads expressed promatrilysin and serum PSA levels that were inhibited by co-injecting with SU5402. Therefore, pharmacological inhibition of FGF receptor signaling results in a decrease in the growth of LNCaP tumors generated subcutaneously by co-injecting LNCaP cells and human prostate fibroblasts. The inhibition in tumor growth was correlated with a decrease in tumor promatrilysin expression and a decrease in serum promatrilysin and PSA.  相似文献   
999.
1000.
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