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991.

Objective

To investigate the relation between donor characteristics and TRALI incidence.

Background

Transfusion-related acute lung injury (TRALI) is a potentially fatal complication of transfusion. In pre-clinical studies and several clinical studies, TRALI has been related to loss of product quality during red blood cell (RBC) storage, called the “storage lesion”. Donor characteristics, as for example age, genetics and life style choices influence this “storage lesion”. We hypothesized that donor sex, age and blood type is related to TRALI incidence.

Methods/materials

We performed a secondary analysis of two cohort studies, designed to identify TRALI risk factors by matching TRALI patients to transfused controls. We obtained donor sex, age and blood type from the Dutch Blood Bank Sanquin and investigated TRALI incidence in patients who were exposed to a certain donor characteristic. We used Kruskal-Wallis testing to compare the number of transfused products and Chi2 testing to compare proportions of TRALI patients and transfused control.

Results

After implementation of the male-donor only plasma strategy, patients received more transfusion products from male donors. However, we did not detect a relation between TRALI incidence and donor sex. Both TRALI patients and transfused controls received mainly products from donors over 41 years old, but donor age did not influence TRALI risk. Donor blood type, the transfusion of blood type-compatible and blood type-matched products also had no influence on TRALI incidence.

Conclusion

We conclude that in two cohorts of TRALI patients, donor age, donor sex and donor blood type are unrelated to TRALI.  相似文献   
992.
993.
Familial lipoprotein lipase deficiency (FLD) is of particular interest to the French Canadian population of Québec since the largest concentration of homozygotes and carriers of this genetic disease in the world resides in this area. We have previously described a missense mutation (M-188) in the lipoprotein lipase (LPL) gene which was present in FLD patients belonging to different ancestries, including a number of French Canadians (Monsalve MV et al. J Clin Invest 1990: 86: 728-734). In the present report, we show that this mutation, although found in largest absolute numbers among French Canadians as compared to other groups in the world, accounts for only a small proportion (24%) of all the LPL mutant alleles in this population. The M-188 occurs either in the homozygote state or as a compound heterozygote with another LPL mutation. Analysis of geographic distribution indicates that the M-188 is more prevalent in western Québec, with the highest carrier rate in the Mauricie region. Genealogical reconstruction leads to the recognition of four founders for M-188, all emigrants from France to Québec in the 17th century.  相似文献   
994.
BACKGROUND: Apple allergy is dominated by IgE antibodies against Mal d 1 in areas where birch pollen is endemic. Apples with significantly decreased levels of Mal d 1 would allow most patients in these areas to eat apples without allergic reactions. OBJECTIVE: The aim of this study was to inhibit the expression of Mal d 1 in apple plants by RNA interference. METHODS: In vitro -grown apple plantlets were transformed with a construct coding for an intron-spliced hairpin RNA containing a Mal d 1-specific inverted repeat sequence separated by a Mal d 1-specific intron sequence. The presence of the construct in transformants was checked by PCR. Expression of Mal d 1 in leaves was monitored by prick-to-prick skin testing in 3 patients allergic to apples and by immunoblotting with a Mal d 1-reactive mAb and with IgE antibodies against Mal d 1. RESULTS: After transformation, plantlets were selected on the basis of having a normal phenotype and growth rate. With PCR, in 6 of 9 selected plantlets, the presence of the gene-silencing construct was demonstrated. By skin prick test it was shown that a wild-type plantlet had significantly ( P < .05) higher allergenicity than 5 of the transformants. Reduction of expression of Mal d 1 was confirmed by immunoblotting. In wild-type and unsuccessful transformants, a strong band was detected with Mal d 1-reactive mAb 5H8 at the expected apparent M r of 17 kDa. This band was virtually absent in the transformants that carried the gene-silencing construct. With human IgE antibodies, the same observations were made. CONCLUSIONS: Mal d 1 expression was successfully reduced by RNA interference. This translated into significantly reduced in vivo allergenicity. These observations support the feasibility of the production by gene silencing of apples hypoallergenic for Mal d 1.  相似文献   
995.
The prevalence of allergic diseases has been increasing continuously and, accordingly, there is a great desire to evaluate the allergenic potential of components in our daily environment (e.g., food). Although there is almost no scientific evidence that genetically modified organisms (GMOs) exhibit increased allergenicity compared with the corresponding wild type significant concerns have been raised regarding this matter. In principle, it is possible that the allergenic potential of GMOs may be increased due to the introduction of potential foreign allergens, to potentially upregulated expression of allergenic components caused by the modification of the wild type organism or to different means of exposure. According to the current practice, the proteins to be introduced into a GMO are evaluated for their physiochemical properties, sequence homology with known allergens and occasionally regarding their allergenic activity. We discuss why these current rules and procedures cannot predict or exclude the allergenicity of a given GMO with certainty. As an alternative we suggest to improve the current evaluation by an experimental comparison of the wild-type organism with the whole GMO regarding their potential to elicit reactions in allergic individuals and to induce de novo sensitizations. We also recommend that the suggested assessment procedures be equally applied to GMOs as well as to natural cultivars in order to establish effective measures for allergy prevention.  相似文献   
996.
Multiple Helicobacter pylori strains may colonize an individual host. Using enzyme-linked immunosorbent assay and line probe assay (LiPA) techniques, we analyzed the prevalence of mixed H. pylori colonization in 127 subjects from Venezuela, a country of high H. pylori prevalence, from three regions representing different population groups: the Andes (Merida), where Caucasian mestizos predominate, a major city near the coast (Caracas), where Amerindian-Caucasian-African mestizos predominate, and an Amazonian community (Puerto Ayacucho), where Amerindians predominate and mestizos reflect Amerindian and Caucasian ancestry. Among 121 H. pylori-positive persons, the prevalence of cagA-positive strains varied from 50% (Merida) to 86% (Puerto Ayacucho) by LiPA. Rates of mixed colonization also varied, as assessed by LiPA of the vacA s (mean, 49%) and m (mean, 26%) regions. In total, 55% of the individuals had genotypic evidence of mixed colonization. vacA s1c, a marker of Amerindian (East Asian) origin, was present in all three populations, especially from Puerto Ayacucho (86%). These results demonstrate the high prevalence of mixed colonization and indicate that the H. pylori East Asian vacA genotype has survived in all three populations tested.  相似文献   
997.
Stress proteins as inducers and targets of regulatory T cells in arthritis   总被引:2,自引:0,他引:2  
Immunization with microbial or mammalian stress proteins or heat-shock proteins in models of experimental autoimmunity has been observed to lead to increased disease resistance. Furthermore, such immunization has been proposed to result in the induction and expansion of T cells that suppress disease upon transfer. Comparisons of microbial heat-shock proteins with other conserved immunogenic proteins of bacterial origin have indicated a unique capacity for heat-shock proteins to induce a regulatory phenotype in T cells, such as reflected by the production of IL10. Also, studies in children with chronic arthritis have indicated that T-cell responses to heat-shock proteins are associated with a benign course of the disease and with remission. Furthermore, in patients, heat-shock-protein-(HSP-) activated T cells were shown to display regulatory phenotypes consistent with CD4+ CD25+ T regulatory cells.  相似文献   
998.
Background: The Seasonal Pattern Assessment Questionnaire (SPAQ) is a frequently used screening instrument in the research on Seasonal Affective Disorder (SAD). Nevertheless, studies on its reliability and validity are relatively scarce. In the present study the reliability and the contrast validity of the SPAQ are investigated. Methods: SAD patients, selected by means of a clinical interview, non-seasonal depressed out-patients, non-depressed out-patients, and a control group, are contrasted to estimate the discriminating power of the SPAQ. Also, the reliability and factor structure of the seasonality and the climate subscales are investigated. To study food intake the Seasonal Food Preference Questionnaire (SFPQ) was developed. Results: The SAD criterion of the SPAQ shows good specificity (94%), but a low sensitivity (44%). Discriminant analysis shows sufficient ability to classify subjects (81% correctly classified). The Global Seasonality Scale has a good internal consistency. It consists of two factors, a psychological factor and a food factor. The SFPQ is sensitive for carbohydrate intake by SAD patients. Limitations: Most SAD patients had received treatment and completed the SPAQ while they were not depressed, which may have influenced the sensitivity. Conclusions: The SPAQ is not sensitive enough to be considered a diagnostic instrument for SAD. Nevertheless, it is accurate enough to be used as a screenings instrument. The only false positives were found in the depressive group. The accuracy of prevalence Figs. can be improved by completion of the SPAQ in the summer months, combined with the completion of a depression scale.  相似文献   
999.
The role of the neuroendocrine environment in the pathogenesis of enteric bacterial infections is increasingly being recognized. Here we report that norepinephrine augments Escherichia coli O157:H7-induced intestinal inflammatory and secretory responses as well as bacterial adherence to intestinal mucosa in a bovine ligated ileal loop model of infection. Norepinephrine modulation of enteritis and adherence was dependent on the ability of E. coli O157:H7 to form attaching and effacing lesions.  相似文献   
1000.
BACKGROUND: Sutureless re-anastomosis per laparoscopy is an alternative for microsurgical re-anastomosis by laparotomy in the treatment of sterilized women with renewed child wish. Our aim was to compare pregnancy rates after both surgical techniques. METHODS: We performed a retrospective cohort study in which consecutive women who underwent sutureless re-anastomosis per laparoscopy were compared to women who underwent microsurgical re-anastomosis by laparotomy. Both procedures were performed in neighbouring hospitals in Northern-Brabant, The Netherlands, and women were matched for age. The primary outcome was time to ongoing pregnancy. RESULTS: Overall, we included 41 women who had sutureless re-anastomosis by laparoscopy, and 41 age-matched women who underwent microsurgical re-anastomosis by laparotomy. The number of women who conceived was 20 (15 ongoing pregnancies) in the sutureless laparoscopic group versus 26 (24 ongoing pregnancies) in the laparotomic group, a difference due to a longer follow-up period in the laparotomic group. Time to ongoing pregnancy was comparable in both groups (P=0.46), with 3 year cumulative ongoing pregnancy rates of 45 and 52% respectively. After adjustment for other prognostic factors, the fecundity rate ratio was 0.97 (95% CI 0.26-3.6), indicating a similar performance of the two techniques. CONCLUSION: The simplified stitchless laparoscopic procedure for reversal of tubal sterilization with the use of a tubal splint, clip fixation of the muscularis and fibrin glue resulted in a promising pregnancy rate, which was similar to the pregnancy rate obtained with the microsurgical re-anastomosis per laparotomy.  相似文献   
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