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151.
2型糖尿病肾病患者血清胱抑素C的检测及意义   总被引:1,自引:0,他引:1  
目的:检测糖尿病患者血清胱抑素C浓度变化,分析其在糖尿病患者早期肾损伤中的作用。方法:根据24h尿白蛋白排泄率(UAER)的测定结果,将104例糖尿病患者分为3组:单纯糖尿病组(SDM组)、早期糖尿病肾病组(EDN组)和临床糖尿病肾病组(CDN组);46名健康者作对照组;采用颗粒增强散射免疫比浊法测定血清胱抑素C水平,常规测定内生肌酐清除率、血肌酐和UAER,并对全部患者胱抑素C血清浓度与尿UAER进行直线相关分析。结果:SDM组,EDN组及CDN组间血清胱抑素C水平均有非常显著性统计学意义(P<0.01),血清胱抑素C与UAER、内生肌酐清除率及血肌酐值有良好相关性(r值分别为0.772,-0.754,0.785,P均<0.01)。结论:血清胱抑素C水平测定有助于2型糖尿病肾病的早期诊断,优于血肌酐和内生肌酐清除率,具有临床应用价值。  相似文献   
152.
Summary Training-induced adaptations in the endocrine system and strength development were investigated in nine male strength athletes during two separate 3-week intensive strength training periods. The overall amount of training in the periods was maintained at the same level. In both cases the training in the first 2 weeks was very intensive: this was followed by a 3rd week when the overall amount of training was greatly decreased. The two training periods differed only in that training period I included one daily session, while during the first 2 weeks of period II the same amount of training was divided between two daily sessions. In general, only slight and statistically insignificant changes occurred during training period I in mean concentrations of serum hormones examined or sex hormone-binding globulin as well as in maximal isometric leg extensor force. However, during training period II after 2 weeks of intensive strength training a significant decrease (P<0.05) was observed in serum free testosterone concentration [from 98.4 (SD 24.5) to 83.8 (SD 14.7) pmol · l–1] during the subsequent week of reduced training. No change in the concentration of total testosterone was observed. This training phase was also accompanied by significant increases (P<0.05) in serum luteinizing hormone (LH) and cortisol concentrations. After 2 successive days of rest serum free testosterone and LH returned to (P<0.05) their basal concentrations. Training period II led also to a significant increase (P<0.05) [from 3942 (SD 767) to 4151 (SD 926) N] in maximal force. These findings suggest that in male strength athletes dividing the amount of training into smaller units may create more effective training stimuli leading to further strength development.  相似文献   
153.
The ability to minimise, if not prevent, large variations in deep body temperature that would otherwise result from some environmental conditions is a homeostatic function of unquestioned benefit that is demonstrated only by the more highly evolved animals. Nevertheless, body temperature is raised above normal values in many pathological conditions. This increase in temperature or fever is an active and co-ordinated response, which indicates the involvement of the CNS. Central injection and lesion studies have shown that the brain, in particular the PO/AH, is the site of action of fever-inducing agents, termed pyrogens. Electrophysiological data show that pyrogens modify the activity of central thermosensitive neurones as if to increase heat gain and decrease heat loss. The common response of fever to pyrogens of diverse origins is attributable to fever being mediated by an endogenous pyrogen released by phagocytic cells in the host. The mechanism by which central neuronal function is disturbed by pyrogens present in the periphery is not known. Tracer studies have yet to demonstrate the passage of a pyrogen across the blood-brain barrier. The possible involvement of several putative neuro- transmitters and modulators in fever has been reviewed here, but most compounds have not been studied sufficiently to allow firm conclusions to be drawn. Much of the data is limited to the effects of the putative mediators on normal thermoregulation but, even when the effect is hyperthermia, such observations do not necessarily indicate a role for the endogenous material in fever. Dose-response curves for agonists and the effects of antagonists are often undetermined. This shortfall in data is due to some extent to the nature of fever; a central response in vivo over several hours. Although fever may enhance other host reactions to combat infection and inflammation, neither this benefit nor the undesirability of antipyretic therapy has been demonstrated unequivocally in either homeothermic laboratory animals or humans. Consequently, antipyretic drugs continue to be used clinically to alleviate the fever, malaise and/or pain commonly associated with disease. The drugs in common usage are the nonsteroidal antipyretic analgesics, many of which also have an anti-flammatory effect. The primary mode of action of these drugs as antipyretics appears at present to be the inhibition of cyclo-oxygenase and a consequent reduction of prostanoid material in pyrogen-sensitive areas of the brain. PGEs in the PO/AH have received most study to date, but other mediators in other parts of the CNS, where the density of pyrogen receptors may be sparse, cannot be discounted and await further investigation.  相似文献   
154.
目的探讨中枢神经系统感染患儿血脑屏障(blood-brain barrier,BBB)与脑脊液(cerebrospinal-fluid,CSF)白蛋白指数的变化。方法采用溴甲酚绿法和免疫比浊法检测18例化脓性脑膜炎患儿急性期、恢复期及22例病毒性脑炎患儿急性期血清和CSF中白蛋白水平,并计算出CSF白蛋白指数。与正常对照组比较。结果化脓性脑膜炎、病毒性脑炎患儿急性期CSF白蛋白、CSF白蛋白指数显著高于正常对照组(P〈0.001),且化脑组显著高于病脑组(P〈0.001)。化脑组恢复期患儿CSF白蛋白、CSF白蛋白指数与对照组无明显差异(P〉0.05)。结论监测CSF白蛋白和CSF白蛋白指数的水平可作为化脓性脑膜炎和病毒性脑炎早期诊断、鉴别诊断,以及判断BBB损伤程度的参考指标。  相似文献   
155.
17 alpha-Alkylated androgens are highly effective in preventing attacks in HAE patients. These drugs, however, seem to be implicated in the development of cholestatic jaundice, peliosis hepatis, and liver tumors. In order to assess the risk-benefit balance of the long-term therapy with androgen derivatives, a follow-up investigation was performed in 13 HAE patients. The results of this study indicate that long-term treatment (15 to 47 mo) with low doses of danazol or stanozolol does not induce significant hepatic damage detectable by laboratory tests or liver biopsy. However, the limited number of patients, although in a rather long period of observation, still suggests a careful control and the use of minimal effective doses.  相似文献   
156.
Separation of the external membranes from freshly converted mechanical schistosomula of Schistosoma mansoni was achieved by osmotic shock under hypertonic conditions, followed by mechanical shearing and ultracentrifugation. Prior to treatment, the schistosomula were surface labeled by introduction of N-DNP-epsilon-aminocaproylphosphatidylethanolamine molecules into their lipid bilayer followed by anti-DNP antibodies and stained with either 125I-protein-A or ferritin labeled secondary anti-DNP antibodies. This label provided a membrane marker by which the purity of the preparation could be assessed at each stage. Fluorescence staining with FITC-conjugated secondary antibodies prior to treatment revealed that the homogeneously stained membrane of the intact schistosomula became swollen and ruptured after the osmotic shock. The isolated membrane pellet was intensely fluorescent. Electron microscopical examination revealed mostly vesicles, some of them with organized multilayer assembly. The vesicles were ferritin labeled, indicating that they originated from the outer surface membrane of the schistosomula. A 100 fold enrichment in the alkaline phosphatase activity and about 300 fold enrichment in acetylcholinesterase activity in the membrane preparations, as compared to the intact schistosomula, was found. The isolated tegument was analyzed by SDS-polyacrylamide gel electrophoresis. The pattern obtained showed three major bands, of molecular weights 69 000, 45 000 and 12 000 alongside with a large number of minor bands. Immunoprecipitation of the isolated 125I-labeled membrane antigens with antisera from chronically infected mice revealed these three major bands together with three other bands of molecular weight 38 000, 23 000 and 16 000.  相似文献   
157.
Toluene diisocyanate (TDI) sensitivity accompanied by nonspecific bronchial hyperresponsiveness occurs in approximately 5% of occupationally exposed workers. We report the case of a 32-yr-old worker followed longitudinally after removal from isocyanate exposure. TDI reactivity was lost 11 mo after removal from exposure and nonspecific bronchial hyperresponsiveness resolved after 17 mo. Bronchial reactivity to radishes (Raphanus sativus), which developed concurrently with TDI reactivity, was lost 2 yr later. Immunopharmacologic results show that the worker's initial decreased ability of lymphocytes to produce cyclic AMP returned to near normal after 2 yr. IgE antibodies to a human serum albumin tolyl monoisocyanate conjugate were still present at this time.  相似文献   
158.
A species-specific receptor for polymerized human albumin (PHALB) has been reported on hepatitis B surface antigen (HBsAg)-carrying particles. Our previous observations that human Clq also binds PHALB in a species-restricted manner led us to investigate the possibility that HBsAg-associated Clq is involved in the PHALB receptor on HBsAg particles. The temperature, ionic strength, and pH requirements necessary for binding of PHALB to both Clq and HBsAg were compared and found to be similar. Normal human serum and purified Clq inhibited the PHABL-HBsAg interaction; the inhibition was markedly reduced in heat-inactivated and Clq-depleted serum. Heat-denatured or reduced and alky-lated Clq failed to inhibit the PHALB-HBsAg binding. Moreover, human Clq was found to be present in purified preparations of HBsAg and the quantity detected paralleled the degree of PHALB-HBsAg binding. While anti-Clq inhibited the PHALB-HBsAg interaction, anti-Clr, -Cls, -C3, and -Ig were not inhibitory. Collagenase treatment of purified HBsAg reduced both PHALB-binding activity and the degree of HBsAg-associated Clq. These observations provide evidence that HBsAg-associated Clq is involved in or near the HBsAg-binding site for PHALB.  相似文献   
159.
There were 26 male and female (nonpregnant and nonlactating) apparently healthy adult (5 to 10 years) field camels (Camelus dromedarius) studied to provide data regarding the normal values of trace elements in serum and different tissues. Blood samples were collected by jugular venepuncture and serum was separated by centrifugation. Tissue samples (liver, heart, striated muscle, spleen, kidney, and hair) were collected during postmortem examinations. All the samples were digested and analyzed for copper, iron, cobalt, and molybdenum using atomic absorption spectrophotometry. The results showed that the highest concentration of iron was present in the spleen and that the concentrations of this element in the liver and kidney were higher than those in the heart, striated muscle, serum, and hair (p<0.05). The lowest mean iron concentration was observed in the serum (p<0.05). The mean copper concentration was highest in liver in comparison to other tissues (p<0.05). No significant differences in cobalt concentrations were detected among different compartments. The mean molybdenum concentration of striated muscle, heart, kidney, spleen, and liver were significantly higher than those of serum and hair (p<0.05). No difference due to sex was detected in different tissue and serum concentrations of trace elements.  相似文献   
160.
Monoclonal antibodies reactive with deoxynivalenol were generated following the immunization of mice with a deoxynivalenol‐mouse serum albumin conjugate. One of the anti‐deoxynivalenol monoclonal antibodies, designated C6–1, exhibited cross‐reactivity with 3‐acetyldeoxynivalenol and 15‐acetyldeoxynivalenol but not with nivalenol, T‐2 tetraol or scirpentriol. An indirect competitive ELISA based on this monoclonal antibody gave 50% inhibition values of 0–6 μg ml‐1 for deoxynivalenol, 0–2 μg ml‐1 for 15‐acetyldeoxynivalenol and 10 μg ml‐1 for 3‐acetyldeoxynivalenol.  相似文献   
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