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81.
Seventy-six children ≤2 years old were prospectively followed for 1 year in a peri-urban community of Mexico City to determine asymptomatic infection and acute diarrhea associated with diarrheagenic Escherichia coli pathotypes (DEPs). By use of a pathogen-specific multiplex PCR, DEPs were sought in 795 stool samples, of which 125 (16%) were positive for DEP; of these, 4 represented shedding episodes and 4 parasite coinfections. Most single-DEP infections (85/117) were asymptomatic (P < 0.001), and of the 32 DEP diarrhea episodes, 41% were associated with atypical enteropathogenic E. coli (aEPEC), 37.5% with enterotoxigenic E. coli, 9% with typical EPEC, 9% with enteroinvasive E. coli, and 3% with Shiga toxin-producing E. coli strains. Among the 76 children, 54 had at least one stool positive for DEP, of which 23 experienced a DEP-associated diarrhea episode. In the last group of children, DEP infection was significantly associated with a diarrhea episode (relative risk [RR] = 2.5; 95% confidence interval [CI], 1.79 to 3.57; P < 0.001), with ETEC (RR = 2.30; 95% CI, 1.49 to 3.54; P = 0.003) and aEPEC (RR = 1.92; 95% CI, 1.23 to 3.0; P = 0.019) being the pathotypes associated with diarrhea. aEPEC-associated diarrhea episodes were frequently in the <12-month age group (RR = 2.57; 95% CI, 1.05 to 6.27; P = 0.04). aEPEC infections were distributed all year round, but associated diarrheal episodes were identified from April to October, with a May-June peak (rainy season). Most ETEC infections and diarrhea episodes characteristically occurred during the summer (rainy season), with a diarrhea peak in August. Of all DEPs, only aEPEC was associated with acute diarrhea episodes lasting 7 to 12 days (P = 0.019). DEPs are important causes of community-acquired enteric infection and diarrhea in Mexican children.  相似文献   
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83.

Introduction

Physicians with substance use disorders receive care that is qualitatively different from and reputedly more effective than that offered to the general population, yet there has been no national study of this distinctive approach. To learn more about the national system of Physician Health Programs (PHPs) that manage the care of addicted physicians, we surveyed all 49 state PHP medical directors (86% responded) to characterize their treatment, support, and monitoring regimens.

Results

PHPs do not provide substance abuse treatment. Under authority from state licensing boards, state laws, and contractual agreements, they promote early detection, assessment, evaluation, and referral to abstinence-oriented (usually) residential treatment for 60 to 90 days. This is followed by 12-step–oriented outpatient treatment. Physicians then receive randomly scheduled urine monitoring, with status reports issued to employers, insurers, and state licensing boards for (usually) 5 or more years. Outcomes are very positive, with only 22% of physicians testing positive at any time during the 5 years and 71% still licensed and employed at the 5-year point.

Conclusion

Addicted physicians receive an intensity, duration, and quality of care that is rarely available in most standard addiction treatments: (a) intensive and prolonged residential and outpatient treatment, (b) 5 years of extended support and monitoring with significant consequences, and (c) involvement of family, colleagues, and employers in support and monitoring. Although not available to the general public now, several aspects of this continuing care model could be adapted and used for the general population.  相似文献   
84.
The authors report the rare association of Prader-Willi syndrome and short-chain acyl-CoA dehydrogenase gene variant. Prader-Willi syndrome, associated with paternal chromosome 15q11-q13 silencing, is characterized by neonatal/infantile hypotonia, growth failure, and neurodevelopmental delays in the first 1 to 2 years of life, typically followed by hyperphagia and obesity. Short-chain acyl-CoA dehydrogenase gene variant, with 625 G-to-A and 511 C-to-T changes, impairs C4-C6 fatty acid metabolism and variably causes neonatal/infantile hypotonia with developmental delays. The authors' patient continues to exhibit the classic severe growth failure of early infancy Prader-Willi syndrome at 40 months. Extensive laboratory investigations indicate that the short-chain acyl-CoA dehydrogenase gene variant is likely preventing or delaying the normal expression of the Prader-Willi syndrome phenotype.  相似文献   
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87.
Results of nonlinear finite element analysis support the Schachar theory of accommodation and demonstrate that the long-held Helmholtz theory of accommodation is impossible.  相似文献   
88.
A recently reported multinational, 8-week double-blind, placebo-controlled study assessing the efficacy of alprazolam versus placebo in the treatment of panic disorder indicated significant differences favoring alprazolam. We now report the results of a three-site, 6-week, double-blind, fixed-dose study comparing alprazolam 2 mg, alprazolam 6 mg, and placebo in 94 patients with panic disorder with or without agoraphobia. Both alprazolam treatment groups (6 mg and 2 mg) improved significantly more than did the placebo treatment group on most outcome measures. Only a few statistically significant differences between the 6 mg and 2 mg alprazolam groups were discerned, although the pattern of treatment response across measures suggested a dose effect. Dropouts in the placebo group were primarily due to lack of efficacy and in the alprazolam 6 mg group were due to side effects, which may have contributed to the limited differences between groups at study end. The findings suggest that many patients may require less than 6 mg of alprazolam per day for effective treatment of panic disorder.  相似文献   
89.
Enteroaggregative Escherichia coli (EAEC) is an emerging enteric pathogen that causes acute and chronic diarrhea among children, human immunodeficiency virus-infected patients, and travelers to developing regions of the world. The pathogenesis of EAEC strains involves the production of biofilm. In this study, we determined the association between presence of putative EAEC virulence genes and biofilm formation in 57 EAEC isolates (as defined by HEp-2 adherence) from travelers with diarrhea and in 18 EAEC isolates from travelers without diarrhea. Twelve nondiarrheagenic E. coli isolates from healthy travelers were used as controls. Biofilm formation was measured by using a microtiter plate assay with the crystal violet staining method, and the presence of the putative EAEC virulence genes aap, aatA, aggR, astA, irp2, pet, set1A, and shf was determined by PCR. EAEC isolates were more likely to produce biofilm than nondiarrheagenic E. coli isolates (P = 0.027), and the production of biofilm was associated with the virulence genes aggR, set1A, aatA, and irp2, which were found in 16 (40%), 17 (43%), 10 (25%), and 27 (68%) of the biofilm producers versus only 4 (11%), 6 (6%), 2 (6%), and 15 (43%) in non-biofilm producers (P = 0.008 for aggR, P = 0.0004 for set1A, P = 0.029 for aatA, and P = 0.04 for irp2). Although the proportion of EAEC isolates producing biofilm in patients with diarrhea (51%) was similar to that in patients without diarrhea (61%), biofilm production was related to the carriage of aggR (P = 0.015), set1A (P = 0.001), and aatA (P = 0.025). Since aggR is a master regulator of EAEC, the presence of aap (P = 0.004), astA (P = 0.001), irp2 (P = 0.0006), pet (P = 0.002), and set1A (P = 0.014) in an aggR versus an aggR-lacking background was investigated and was also found to be associated with biofilm production. This study suggests that biofilm formation is a common phenomenon among EAEC isolates derived from travelers with or without diarrhea and that multiple genes associated with biofilm formation are regulated by aggR.  相似文献   
90.
Blood transfusion is one of the principal routes of transmission of Chagas' disease, a major endemic disease in Latin America. Methods for blood screening are not accurate and may yield false results that lead to high social and economic costs. This study compares two methods of diagnosing Chagas' disease (indirect immunofluorescence and hemagglutination) and several enzyme-linked immunosorbent assays (ELISAs) with regard to specificity and sensitivity, by using human sera with known serologic and parasitologic characteristics, as well as samples with discrepant results on conventional serologic tests. An ELISA using recombinant antigens showed no cross-reactivity with sera that were positive for other diseases. All evaluated ELISAs performed well, and their use may lead to a reduction of more than 50 percent in the number of discordant sera. Further improvements are needed in view of the complexity of the serologic diagnosis of Chagas' disease.  相似文献   
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