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61.
Acute porphyria is rare in orientals. We describe a Chinese woman with recurrent generalised tonic-clonic seizures and abdominal pain. Genomic DNA studies identified a heterozygous base substitution from guanine to adenine at nucleotide position 503, resulting in substitution of arginine by histidine at position 168 of the protein (R168H). This genetic abnormality is similar to the mutation reported in Caucasians with variegate porphyria. To the best of our knowledge, this is the first report in the English literature a Chinese patient with variegate porphyria with an identifiable mutation. A brief review of porphyria is presented.  相似文献   
62.
目的探讨银杏叶制剂对急性脑梗死的治疗效果。方法随机选择银杏叶制剂配合治疗及常规药物治疗急性脑梗死患者各42例,对不同时期单光子发射电子计算机断层扫描(SPECT)、经颅多普勒超声检查(TCD)及血液流变学进行对比分析。结果银杏叶制剂配合治疗组治愈率及显效率明显高于常规药物治疗组(P<0.01);银杏叶治疗组血液流变学指标全血粘度及血浆粘度均明显降低(P<0.01);SPECT及TCD均示脑缺血病灶有不同程度改善,但常规药物治疗组血液流变学、SPECT、TCD改善均不明显。结论银杏叶制剂治疗急性脑梗死效果显著。  相似文献   
63.
According to the 1990 census, the highly diverse Asian and Pacific Islander (API) American population has doubled in size from 1980 to 1990, and is now the nation's fastest growing minority group. Several studies have documented this population's comparative underuse of mental health services. A review of recent studies on the mental health of Asian and Pacific Island elders identifies a number of risk factors and protectors. Elder APIs appear to have poorer mental health compared to white counterparts, but not the poorest mental health within their own ethnic group. Within-group differences emerge, with recent immigrant groups and colonized populations appearing as most at-risk for mental health problems. A critical variable on this population's mental health status appears to be socioeconomic status,and yet an analysis of other demographic variables, notably nativity and gender, remain contradictory. A research agenda is proposed and implications for mental health administrators are suggested.  相似文献   
64.
Objective To examine behavioral and body size influences on the underreporting of energy intake by obese and normal-weight women.Design Seven-day estimated food records were kept by subjects before they participated in a 49-day residential study. Self-reported energy intake was compared with energy intake required to maintain a stable body weight during the residential study (reference standard). Energy intake bias and its relationship to various body size and behavioral measures were examined.Subjects Twenty-two, healthy, normal-weight (mean body mass index [BMI]=21.3) and obese (mean BMI=34.2) women aged 22 to 42 years were studied.Statistical analyses Analysis of variance, paired t test, simple linear regression, and Pearson correlation analyses were conducted.Results Mean energy intake from self-reported food records was underreported by normal-weight (−9.7%) and obese (−19.4%) women. BMI correlated inversely with the energy intake difference for normal-weight women (r=−.67, P=.02), whereas the Beck Depression Inventory correlated positively with the energy intake difference for obese women (r=.73, P<.01).Conclusion/applications Results suggest that body size and behavioral traits play a role in the ability of women to accurately self-report energy intake. BMI appears to be predictive of underreporting of energy intake by normal-weight women, whereas emotional factors related to depression appear to be more determinant of underreporting for obese women. Understanding causative factors of the underreporting phenomenon will help practicing dietitians to devise appropriate and realistic diet intervention plans that clients can follow to achieve meaningful change. J Am Diet Assoc. 1999;99:300-306.  相似文献   
65.
These studies were designed to test the hypolipidemic activity of green tea epicatechins (GTE) isolated from jasmine green tea. In Experiment 1, three groups of hamsters were given a semisynthetic diet containing 200 g lard/kg and 1 g cholesterol/kg for 4 wk. The control group received distilled water, and the other two groups received either 15 g/L green tea water extract (GTWE) or 5.0 g/L GTE solution. Both the GTWE and GTE groups had lower concentrations of serum total cholesterol (TC) and triacylglycerols (TG) than the controls (P < 0.05). In Experiment 2, four groups of hamsters received tap water as the drinking fluid, but they were given the same high fat and cholesterol diet supplemented with 0 (control), 1.1, 3.4 or 5.7 g GTE/kg diet. The hypolipidemic effect of jasmine GTE was dose dependent. In Experiment 3, the time-course of changes in serum TC and TG was monitored in hamsters given the high fat diet supplemented with 5.7 g GTE/kg in comparison with that of controls. The hypolipidemic effects of dietary GTE were evident after feeding for 2 wk. Dietary supplementation of GTE did not affect liver fatty acid synthase. However, GTE-supplemented hamsters had higher fecal excretions of total fatty acids, neutral sterols and acidic sterols compared with the control group. In Experiment 4, hamsters were fed nonpurified diet; the control group drank distilled water, and the GTE group drank distilled water containing 5.0 g GTE/L. No differences in activities of 3-hydroxy-3-methyl glutaryl coenzyme A reductase and intestinal acyl CoA:cholesterol acyltransferase were observed. This study suggests that the hypolipidemic activity of GTE is not due to inhibition of synthesis of cholesterol or fatty acid but is most likely mediated by its influence on absorption of dietary fat and cholesterol.  相似文献   
66.
PURPOSE: To determine and compare the diagnostic performance of fetal middle cerebral (MCA), renal (RA), and umbilical (UA) arterial Doppler ultrasonography (US) for prediction of adverse perinatal outcome in suspected intrauterine growth restriction (IUGR). MATERIALS AND METHODS: Two hundred ninety-three small-for-gestational age fetuses (24-39 weeks at recruitment and US-estimated weight or abdominal circumference below 10th percentile) were prospectively examined with Doppler US of the UA, MCA, and RA. Clinicians were blinded to MCA and RA Doppler measurements. RESULTS: Seventy-six fetuses (25.9%) had at least one major or minor adverse perinatal outcome. Major outcomes included stillbirth, neonatal death, neurologic complication, and necrotizing enterocolitis. The MCA pulsatility index (PI), compared with the UA PI and RA PI, was more sensitive (72.4% vs 44.7% and 8.3%) but less specific (58.1% vs 86.6% and 92.6%) in predicting adverse outcome. The UA PI had the highest positive likelihood ratio (ratio, 3.3); the MCA PI had the lowest negative likelihood ratio (ratio, 0.48). When gestational age at the first Doppler US examination was less than 32 weeks, the MCA PI had a sensitivity of 95.5% and negative predictive value of 97.7% for major adverse outcome (negative likelihood ratio, 0.10). CONCLUSION: In suspected IUGR, while an abnormal UA PI is a better predictor of adverse perinatal outcome than an abnormal MCA or RA PI, a normal MCA PI may help to identify fetuses without major adverse perinatal outcome, especially before 32 weeks gestational age.  相似文献   
67.
Myles RT  Fong B  Esses SI  Hipp JA 《Spine》1999,24(5):476-480
STUDY DESIGN: Kappa statistics were used to compare the accuracy of two different techniques for verifying pedicle screw pilot hole placement in cadaveric vertebrae. OBJECTIVE: To determine whether clinicians radiographically detect misplaced pedicle screw holes with greater sensitivity and specificity when beaded wires rather than straight Kirschner wires are used. SUMMARY OF BACKGROUND DATA: Pedicle screws commonly are used in orthopedic surgery to obtain and maintain spinal stability. Pedicle screws are reportedly misplaced at a rate of 20% to 40%. Radiographic verification is commonly used to place pedicle screw pilot holes, but this technique is known to be less than 100% accurate. Computer-assisted techniques may allow more accurate screw placement, but these techniques require expensive equipment. METHODS: Pedicle screw pilot holes were drilled into 12 human lumbar and thoracic vertebrae. Some of the holes were misplaced deliberately so that they violated the pedicle walls. Lateral and posteroanterior radiographs of the vertebrae were evaluated by 13 experienced orthopedic spine surgeons and 3 inexperienced observers. At different times, the observers were shown radiographs depicting Kirschner wires or beaded wires placed in the pilot holes. Observers indicated whether they thought the pedicle screw pilot hole violated the pedicle. RESULTS: The sensitivity and specificity of using posteroanterior or lateral radiographs to detect misplaced pedicle screws were increased when beaded wires were placed in the pilot holes. CONCLUSIONS: Radiographic evaluation of beaded wires placed in pedicle screw pilot holes can be both sensitive and specific for misplaced screws. The highest sensitivity and specificity were found using posteroanterior radiographs.  相似文献   
68.
Large palatomaxillary and oromandibular defects have a dramatic impact on speech, deglutition, mastication, and cosmesis. Traditional methods of reconstruction, such as locoregional flaps, free bone grafts, alloplastic materials, and prosthetic devices, have difficulty providing meaningful aesthetic and functional reconstruction of these defects. This article discusses current concepts in the reconstruction of large composite palatomaxillary and oromandibular defects with an emphasis on the role of free tissue transfer, including the factors to be evaluated when choosing a method of reconstruction, indications for specific donor sites, and recent technical refinements.  相似文献   
69.
Studies of minority ethnic women and cancer screening have, in the past, suffered from many theoretical and methodological weaknesses. In addition, no attempts have been made to study the complexity of the issue involved in the intercultural context, or the possible contribution of women's experiences to low uptake rates. In order to further our understanding of the issues, an alternative approach, participatory action research (PAR), was adopted to identify factors that might have contributed to the persistently low participation of minority ethnic women in the cervical screening programme, and address them collaboratively. This paper presents the key findings of the ‘problem identification' phase of the project. Using mainly the focus-group method, it explores both smear takers' and minority ethnic women's perceptions and experiences of cervical screening. Data suggest that there was a divergence in perceptions held by these groups regarding cervical screening, which contributed to negative experiences for both groups. There is also clear evidence of dysfunctional clinical communication arising from these differing perceptions. Opportunistic screening at post-natal examination adopted by many general practices appeared to have perpetuated the perceptions that the majority of minority ethnic women held about the purpose of the smear test. Compounded by language differences, the majority of women who had undergone smear testing understood neither the purpose of screening programme nor the procedure of the test. This has clear implications for promoting regular uptake, and more importantly for informed consent and choice.  相似文献   
70.
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