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91.

Background

The episode-of-care concept promulgated by the federal government requires hospitals to assume the cost burden for all care rendered up to 30 days after discharge, including all readmissions occurring in that time. Although surgical site infections (SSIs) are a leading cause of readmission after total joint arthroplasties (TJA) and spine surgery, it is unclear whether these readmissions occur relative to the 30-day period.

Questions/Purposes

We determined whether (1) most readmissions for SSIs occurred in 30 days, (2) the type of procedure performed affected the timing of readmission, and (3) the type of infecting organism influenced the timing of readmission.

Methods

From our hospital database we identified 91 patients treated with elective TJAs and spine surgery from 2007 through 2010 who were readmitted with SSIs. Of the 91 patients, 46 had undergone spine surgery and 45 had TJAs. For each of these readmissions, we determined the type of surgery, the length of time from initial discharge to readmission, and the type of infecting organism.

Results

Readmissions after spine surgery were more likely to occur within 30 days of discharge (80.4% for spine, 58.3% for TJAs). In the TJA cohort, there was a trend toward readmissions occurring within 30 days of discharge more often in the THA subset. We identified no correlation between type of infecting organism and timing of readmission.

Conclusions

With the episode-of-care model, SSIs pose a substantial cost burden for hospitals since the majority would be included in the 30-day period included in the bundled reimbursement.  相似文献   
92.
Serological assays are increasingly being used to measure HIV incidence in cross-sectional studies, but their specificity to determine incident infections remains problematic. We estimated the specificity of the BED assay in a cohort of long-term HIV-infected adults before and during antiretroviral treatment (ART) and evaluated an HIV avidity assay to detect BED-based false-recent results. We used the BED assay to test stored specimens from known long-term HIV-1-infected adult Ugandans before and at 3, 12, and 24 months after ART initiation. We evaluated the frequency of false-recent classifications by ART status and CD4(+) T(+) cell count. Specimens classified as BED false-recent were further tested with an avidity assay. In all, 950 blood specimens from 253 adults were tested with the BED assay. Of these, 149 (15.7%) specimens tested false-recent and 64 (24.9%) individuals tested false-recent at least once. Among all specimens tested, the proportion of false-recent rose with increasing CD4(+) cell count (<250 cells/μl: 11.3%, 250-499: 17.8%, ≥500: 21.4%; p for trend=0.002). Of 197 persons with all four BED results available, 75.6% were classified as long-term infected throughout and 8.1% as false-recent throughout; the remainder changed classification once (12.2%) or twice (4.1%). Of 105 false-recent specimens retested with the avidity assay, 101 (96.2%) were correctly classified as "long-term." The BED assay's specificity varied with CD4(+) cell count and use of ART. Knowledge of these parameters for blood samples could improve incidence estimates using the BED assay. The additional use of an avidity assay may help to minimize the proportion of BED false-recent specimens.  相似文献   
93.
Rationale: Elevated long pentraxin-3 (PTX3) levels are associated with the development of primary graft dysfunction (PGD) after lung transplantation. Abnormalities in innate immunity, mediated by PTX3 release, may play a role in PGD pathogenesis. Objectives: Our goal was to test whether variants in the gene encoding PTX3 are risk factors for PGD. Methods: We performed a candidate gene association study in recipients from the multicenter, prospective Lung Transplant Outcomes Group cohort enrolled between July 2002 and July 2009. The primary outcome was International Society for Heart and Lung Transplantation grade 3 PGD within 72 hours of transplantation. Targeted genotyping of 10 haplotype-tagging PTX3 single-nucleotide polymorphisms (SNPs) was performed in lung transplant recipients. The association between PGD and each SNP was evaluated by logistic regression, adjusting for pretransplantation lung disease, cardiopulmonary bypass use, and population stratification. The association between SNPs and plasma PTX3 levels was tested across genotypes in a subset of recipients with idiopathic pulmonary fibrosis. Measurements and Main Results: Six hundred fifty-four lung transplant recipients were included. The incidence of PGD was 29%. Two linked 5' region variants, rs2120243 and rs2305619, were associated with PGD (odds ratio, 1.5; 95% confidence interval, 1.1 to 1.9; P = 0.006 and odds ratio, 1.4; 95% confidence interval, 1.1 to 1.9; P = 0.007, respectively). The minor allele of rs2305619 was significantly associated with higher plasma PTX3 levels measured pretransplantation (P = 0.014) and at 24 hours (P = 0.047) after transplantation in patients with idiopathic pulmonary fibrosis. Conclusions: Genetic variants of PTX3 are associated with PGD after lung transplantation, and are associated with increased PTX3 plasma levels.  相似文献   
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96.
Oncotype DX has been criticized for not providing significantly more prognostic information than histopathologic analysis. Oncotype DX was validated in cohorts that included poor prognostic factors (HER2‐positive, low‐estrogen receptor [ER] expression), raising the question: if patients with known high recurrence rates are excluded, is the Recurrence Score (RS) still valid? Our purpose was to determine if RS can be predicted with readily available measures. One hundred and twenty samples from August 2006 to November 2010 that underwent Oncotype DX testing were analyzed. Data included RS, ER, progesterone receptor (PR), HER2, and Ki67 status by immunohistochemistry (IHC). IHC data were used to create two linear regression models to predict RS. SAS's JMP‐7 was used for statistical analysis. When comparing Oncotype DX‐ and IHC‐derived ER and PR values, there were 21 discordant samples. The linear regression model PRS‐F created with IHC data (ER, PR, HER2, Ki67) from all samples (= 120) had an adjusted R2 = 0.60 indicating a good model for predicting RS. The PRS‐R model was built without low‐ER and HER2‐positive samples (= 110). It had an adjusted R2 = 0.38 indicating poor prediction of RS. Oncotype DX data showed good concordance with IHC for ER‐ and PR‐expression in this cohort. Low‐ER samples had high RS. After removing low‐ER and HER2‐positives, calculating RS with PRS‐R from remaining data showed poor predictive power for RS (adjusted R2 = 0.38). This result questions whether RS is prognostic in this subgroup (who would most benefit from further clarification of recurrence risk) and independent of pathology, or is simply producing random RS values. Data bases available to Genomic Health can resolve this issue.  相似文献   
97.
98.

Background

Low socioeconomic status (SES) exacerbates the high rate of smoking relapse in women following childbirth.

Purpose

This study examined multiple models of potential mechanisms linking SES and postpartum smoking relapse among women who quit smoking due to pregnancy.

Methods

Participants were 251 women enrolled in a randomized clinical trial of a new postpartum smoking relapse prevention intervention. Four models of the prepartum mechanisms linking SES and postpartum smoking relapse were evaluated using a latent variable modeling approach.

Results

Each of the hypothesized models were a good fit for the data. As hypothesized, SES indirectly influenced postpartum smoking relapse through increased prepartum negative affect/stress, reduced sense of agency, and increased craving for cigarettes. However, the model that included craving as the sole final pathway between SES and relapse demonstrated superior fit when compared with all other models.

Conclusions

Findings have implications for future interventions that aim to reduce postpartum relapse.  相似文献   
99.
Neurotransmitters other than dopamine are recognized as having modulatory roles within the basal ganglia and can influence the basal ganglia dopaminergic system to alter activity of the direct and indirect pathways. Many nondopaminergic neurotransmitter systems have been implicated in the mechanisms contributing to the motor features of Parkinson's disease (PD). Thus, it is now well established that neurotransmitter systems, including glutamatergic, GABAergic, cholinergic, noradrenergic, serotonergic, opioidergic, histaminergic, and adenosinergic systems, are affected in the pathogenesis of PD. Nondopaminergic neurotransmitter systems are thus targets for the development of novel therapies for motor symptoms and motor complications in PD. Over the last 5 years, more than 20 randomized, control trials (RCTs) in PD investigating drugs that target several of these nondopaminergic neurotransmitter systems for the treatment of motor features have been completed. There are at least 15 additional RCTs that are ongoing or planned. Here, we review these RCTs to highlight the potential nondopaminergic pharmacological therapies for treatment of motor features of PD. Nondopaminergic drugs are not expected to replace dopaminergic strategies, but further development of these drugs will likely yield novel approaches with positive clinical implications. © 2012 Movement Disorder Society  相似文献   
100.
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