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991.
The objectives of the present study were to establish dental caries prevalence (percentage with caries) and experience in the primary and permanent dentition (dmft and DMFT) of 6 to 13-year-old schoolchildren in Campeche, Mexico, and to estimate the contributing roles of the likely risk indicators. A cross-sectional study was carried out in 1,644 children aged 6-13 years. Self-administered questionnaires obtained information on social, economic, behavioral, and demographic variables. The primary dentition of 1,309 children and the permanent dentition of 1,640 children were evaluated in the oral examinations. The main outcome measures were DMFT, dmft, and SiC indices. Data were modeled using logistic regression analysis. The overall caries prevalence was 77.4%, 73.6% in the primary dentition (61.6% in 6-year-olds), and 49.4% in the permanent dentition. The dmft and DMFT indices were 2.85+/-2.73 and 1.44+/-2.05, respectively (DMFT = 3.11+/-2.62 in 12-year-olds). The SiC index was 6.05 at 12 years of age. Associated variables to dental caries in both dentitions were presence of enamel defects, presence of dental plaque, low socio-economic status, female sex, and older age. Mother's schooling was negatively associated (OR = 0.95) with caries in primary dentition. Caries experience in the primary dentition (OR = 6.02) was positively associated with caries in the permanent dentition. Dental caries status in these Mexican children was closer to the goals proposed by the WHO/FDI for 2000 than previous studies. This study has identified clinical, socio-economic, and behavioral determinants for dental caries in primary and permanent dentition on Mexican schoolchildren.  相似文献   
992.
PURPOSE: This in vivo investigation compared the oral candidal population between heat-cured acrylic resin and nickel-chromium-beryllium alloy in maxillary complete dentures in HIV-infected patients. MATERIALS AND METHODS: Split-palate maxillary complete dentures were fabricated for 19 HIV-infected patients: one-half of the palate was made in acrylic resin and the other half in nickel-chromium-beryllium. Patients were divided into low or high CD4+ lymphocyte count groups. Dentures were worn for 5 months. Palatal mucosa was clinically evaluated at baseline, 1, 3, and 5 months after denture insertion. Specimens were collected at 1, 3, and 5 months using a modified imprint culture method. Speciation of Candida was performed using a chromogenic culture medium. Two-sample t-test was employed to determine effects and significant interactions between the control and test groups and the low and high CD4+ lymphocyte groups. A chi(2) test analyzed and compared the results of the clinical evaluation (p < 0.05). RESULTS: Significant differences were observed in the colony counts between both materials during the third (p= 0.046) and fifth months (p= 0.039). The low CD4+ group demonstrated significant differences during the third (p= 0.03) and fifth months (p= 0.05). There were no significant differences between the species of Candida that colonized either material with the exception of Candida dubliniensis (p < 0.001) and "Others" (p < 0.001) during the first and fifth months. There were no significant differences on the clinical appearance of the palatal mucosa between both materials (p= 1.00). CONCLUSIONS: The metal base proved to be effective in decreasing the fungal growth typically present in complete dentures. Although overt clinical manifestations were not present, colony counts of Candida species were high in the acrylic resin denture bases of these patients. This investigation demonstrated that metal base complete dentures provide an important alternative dental service for edentulous HIV-positive and other patients who are particularly prone to higher incidences of fungal infections.  相似文献   
993.
目的回顾性分析成都军区总医院(GH)在汶川地震与芦山地震应急医学救援中的异同,探讨应急医学救援体系从“汶川”到“芦山”的转变,旨在为今后的灾难医学救援提供有益参考。方法对比分析GH在汶川地震和芦山地震收治伤员性别、年龄、婚姻状况、民族构成、伤员流、来院时间分布、伤情分类、转归及医疗费用的差异,并进一步探讨两次地震救援中一线和二线医院收治方案、上级专家巡诊会诊模式、二级职能科室在医学救援中的职能转变、公共信息平台在地震救援中的应用等方面的变化。结果汶川地震和芦山地震伤员在性别、年龄、婚姻状况、民族构成等方面无统计学差异,但在伤情分类、医疗费用等方面存在一定统计学意义。芦山地震“伤员流”峰值时间较汶川地震时显著提前,伤员转归较汶川地震好。国家级、院级专家会诊巡诊模式的转变在一定程度上提高了伤员的救治效率,另外,二级职能科室参与医学救援过程的模式使应急救援过程更加有序、合法。结论在汶川地震医学救援的经验教训的基础上,在芦山地震医学救援中,GH从地震伤员的分类救治、空中转运、各级专家检诊模式以及医院二级职能部门的管理等方面大胆改革创新,提出应急救援遵循“变应急为常态、变无序为有序”的基本原则,极大地提高了救治效率。  相似文献   
994.
995.
The performance of a real-time PCR-based assay was retrospectively analyzed (according to European Organization for Research and Treatment of Cancer/Mycosis Study Group criteria) in the samples of patients with invasive aspergillosis. A total of 711 serial samples (356 whole-blood and 355 serum samples) from 38 adult patients were analyzed. The Aspergillus fumigatus PCR assay results were positive for 89 of 356 (25%) whole-blood samples and 90 of 355 (25.35%) serum samples. Positive PCR results were seen in 29 of 31 (93.5%) patients for which serum was analyzed and in 31 of 33 (93.9%) cases with whole-blood specimens. Both blood and serum samples were available in 26 cases, and significant differences were not observed in this subgroup of cases. The average number of threshold cycles (C(T)) for positive blood samples was 37.6, and the average C(T) for serum was 37.4. The DNA concentration ranged between 2 and 50 fg per μl of sample, with average DNA concentrations of 10.2 and 11.7 fg in positive blood and serum samples, respectively (P > 0.01). The performance of this PCR-based quantitative assay was similar for both serum and blood samples. We recommend serum samples as the most convenient hematological sample to use for Aspergillus DNA quantification when serial determinations are done.  相似文献   
996.
997.
998.
The genomic structure of Pelargonium line pattern virus (PLPV), a tentative member of a proposed new genus within the family Tombusviridae, has been recently determined. However, little is known about the genetic variability and population structure of this pathogen. Here, we have investigated the heterogeneity of PLPV isolates from different origins by sequence analysis of a 1817nt fragment encompassing the movement (p7 and p9.7) and coat protein genes as well as flanking segments including the complete 3' untranslated region. We have evaluated the selective pressures operating on both viral proteins and RNA genome in order to assess the relative functional and/or structural relevance of different amino acid or nucleotide sites. The results of the study have revealed that distinct protein domains are under different selective constraints and that maintenance of certain primary and/or secondary structures in RNA regulatory sequences might be an important factor limiting viral heterogeneity. We have also performed covariation analyses to uncover potential dependencies among amino acid sites of the same protein or of different proteins. The detection of linked amino acid substitutions has permitted to draw a putative network of intra- and interprotein interactions that are likely required to accomplish the different steps of the infection cycle. Finally, we have obtained phylogenetic trees that support geographical segregation of PLPV sequences.  相似文献   
999.

Objectives

Life expectancy in rheumatoid arthritis (RA) patients is reduced by 3-10 years, probably due to cerebrovascular and cardiovascular diseases associated with atherosclerosis. In the present study, we wanted to verify if previously reported IgA anti-beta 2-glycoprotein I (2GPI) antibodies possibly represented an independent risk factor for atherosclerosis in RA patients during a longer period of follow up.

Methods

The follow-up study (after 5.5 years) comprised all initially included patients and controls (premenopausal women, non-diabetic, normotensive at the start of the study), except for two RA patients (one died and one not available). The same clinical, laboratory and ultrasound assessments were performed.

Results

Patients and controls were divided into three categories: Intima-media thickness (IMT) progressors, plaque progressors, IMT and plaque progressors. In controls, 55% represented IMT progressors and 5% IMT and plaque progressors. No statistically significant differences were detected comparing the progressors with delta (Δ = difference between follow-up and baseline study for each group in a time span of 5.5 years) LDL cholesterol, homocysteine and IgA anti-β2GPI. In patients, there were 48.5% IMT progressors, 5.8% plaque progressors and 19.1% IMT and plaque progressors. The progression was statistically significant associated with the levels of Δ homocysteine and Δ apolipoprotein B but not with LDL cholesterol and IgA anti-β2GPI.

Conclusions

The follow-up study showed advanced atherosclerosis in RA patients compared to sex and age matched controls. However, we were not able to confirm our initial impression that IgA anti-β2GPI might represent an independent risk factor for atherosclerosis.  相似文献   
1000.
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