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61.

Background

Early recognition and accurate risk stratification are important in the management of arrhythmogenic right ventricular cardiomyopathy (ARVC). Identification of predictors of outcome by cardiovascular magnetic resonance (CMR) in patients undergoing evaluation for ARVC is limited. We investigated the predictive value of morphological abnormalities detected by CMR for major clinical events in patients with suspected ARVC.

Methods

We performed a longitudinal study on 369 consecutive patients with at least one criterion for ARVC. Abnormal CMR was defined by the presence of one of the following: increased right ventricular (RV) volumes, reduced RV ejection fraction, RV regional wall motion abnormalities, myocardial fatty infiltration, and myocardial fibrosis. The end-point was a composite of cardiac death, sustained ventricular tachycardia, ventricular fibrillation, and appropriate ICD discharge.

Results

Twenty patients met the composite end-point over a mean follow-up of 4.3 ± 1.5 years. An abnormal CMR was an independent predictor of outcomes (p < 0.001). The presence of multiple abnormalities heralded a particular high risk of events (HR 23.0, 95% CI 5.7–93.2, p < 0.001 for 2 abnormalities; HR 35.8, 95% CI 9.7–132.6, p < 0.001 for 3 or more abnormalities). The positive predictive value of an abnormal CMR study was 21.0% for an adverse event, whilst the negative predictive value of a normal CMR study was 98.8% over the follow-up period.

Conclusions

CMR provides important prognostic information in patients under evaluation for ARVC. A normal study portends a good prognosis. Conversely, the presence of multiple abnormalities identifies a high risk group of patients who may benefit from ICD implantation.  相似文献   
62.
Human myometrium and leiomyomas express granulocyte macrophage-colony-stimulating factor (GM-CSF), transforming growth factor-beta (TGFbeta), and their receptors. Overexpression of TGFbeta and, to a limited extent, GM-CSF has been associated with tissue fibrosis throughout the body, including leiomyomas. The objective of the present study was to determine the action of GM-CSF on leiomyoma and myometrial smooth muscle cells (LSMC and MSMC) and examine whether the action of GM-CSF is mediated through the induction of TGFbeta1 expression. Using competitive quantitative RT-PCR and enzyme-linked immunosorbent assay, we found that LSMC express significantly higher GM-CSF messenger ribonucleic acid (mRNA; 0.6 +/- 0.1 x 10(3) copies of mRNA/microg total RNA) and protein (0.75 +/- 0.2 ng/mL) than MSMC (0.5 +/- 0.1 x 10(2) copies of mRNA and 0.45 +/- 0.07 ng/mL protein; P < 0.05). In addition, LSMC expressed significantly higher TGFbeta1 mRNA (1.6 +/- 0.3 x 10(4) copies of mRNA/microg total RNA) than MSMC (2.4 +/- 0.4 x 10(3) copies) and synthesized and secreted more TGFbeta1 protein (1.7 +/- 0.2 vs. 0.5 +/- 0.02 ng/mL); whereas MSMC contained more cell-associated TGFbeta1 (56.2 +/- 1.2 ng/mL) than LSMC (35.2 +/- 1.2 ng/mL; P < 0.05). We found that GM-CSF (0.01-100 ng/mL) has limited mitogenic activity for LSMC but not for MSMC determined by the rate of [3H]thymidine incorporation and cell proliferation assay. However, GM-CSF at 1 ng/mL increased its own production, the expression of TGFbeta1 mRNA, the cell-associated TGFbeta1 protein content in both cell types, and TGFbeta1 released into the culture-conditioned medium of LSMC (P < 0.05). TGFbeta1 also increased its own mRNA and protein expression, but had no effect on cell-associated TGFbeta1 in both cell types (P < 0.05). Cotreatment of LSMC and MSMC with GM-CSF and TGFbeta1 induced changes similar to those produced by GM-CSF in both cells. In conclusion, our data suggest that GM-CSF is not a mitogen for MSMC and LSMC, but it regulates its own expression and the expression of TGFbeta1 by these cells, a regulatory interaction that may account for the GM-CSF-induced tissue fibrosis that occurs in leiomyomas.  相似文献   
63.
Ten percent of newly diagnosed myeloma patients treated with any type of chemotherapy develop deep venous thrombosis (DVT). Thalidomide has proven activity in refractory multiple myeloma (MM), and although single-agent thalidomide has minimal prothrombogenic activity, its combination with cytotoxic chemotherapy is associated with a significantly increased risk of DVT. We analyzed the incidence of DVT in 232 MM patients who received a combination of chemotherapy and thalidomide on 2 protocols that differed only by the inclusion of doxorubicin in one. DT-PACE (dexamethasone/thalidomide/cisplatin/doxorubicin/cyclophosphamide/etoposide) was offered to patients with preceding standard dose therapy, but no prior autotransplantation, while DCEP-T (dexamethasone/cyclophosphamide/etoposide/cisplatin/thalidomide) was administered for relapse after transplantation. If there were signs or symptoms suggestive of DVT, patients received additional investigations, including Doppler ultrasonography, followed by venography if indicated. Only patients on DT-PACE but not DCEP-T experienced an increased incidence of DVT. A statistical association between the incidence of DVT and combination chemotherapy including doxorubicin (P =.02) was observed; this association was confirmed on multivariate analysis. MM patients treated with thalidomide and doxorubicin have a high risk of developing DVT.  相似文献   
64.
Bovine tropical Theileriosis caused by Theileria annulata is an economically important disease of cattle. An enzyme linked immunosorbent assay (ELISA) was used to determine antibody levels in vaccinated and unvaccinated cattle, using cellular schizont as antigen and its results were compared with immunofluorescent assay (IFA). For this test 126 sera collected (105 vaccinated, 31 not vaccinated) from cows and assayed with ELISA which among them 104 sera were positive and 32 sera were negative. Same sample assayed with IFA in which 99 were positive sera and 37 were negative sera. Thereby the sensitivity and specificity of this ELISA on comparsion with lEA were 95.5% and 66.6% respectively. This study revealed that ELISA could be successfully used for both differentiating vaccinated and not vaccinated cattle and obtaining the titer of vaccinated cattle.  相似文献   
65.
The prothrombin time (PT) represents the most commonly used coagulation test in clinical laboratories. The PT is mathematically converted to the international normalized ratio (INR) for use in monitoring anticoagulant therapy with vitamin K antagonists such as warfarin in order to provide test results that are adjusted for thromboplastin and instrument used. The INR is created using two major PT ‘correction factors’, namely the mean normal PT (MNPT) and the international sensitivity index (ISI). Manufacturers of reagents and coagulometers have made some efforts to harmonizing INRs, for example, by tailoring reagents to specific coagulometers and provide associated ISI values. Thus, two types of ISIs may be generated, with one being a ‘general’ or ‘generic’ ISI and others being reagent/coagulometer-specific ISI values. Although these play a crucial role in improving INR results between laboratories, these laboratories reported INR values are known to still differ, even when laboratories use the same thromboplastin reagent and coagulometer. Moreover, ISI values for a specific thromboplastin can vary among different models of coagulometers from a manufacturer using the same method for clot identification. All these factors can be sources of error for INR reporting, which in turn can significantly affect patient management. In this narrative review, we provide some guidance to appropriate ISI verification/validation, which may help decrease the variability in cross laboratory reporting of INRs.  相似文献   
66.
In December 2019, a new type of coronavirus was detected for the first time in Wuhan, Hubei Province, China. According to the reported data, the emerging coronavirus has spread worldwide, infecting more than fifty-seven million individuals, leading to more than one million deaths. The current study aimed to review and discuss the hematological findings of COVID-19. Laboratory changes and hematologic abnormalities have been reported repeatedly in COVID-19 patients. WBC count and peripheral blood lymphocytes are normal or slightly reduced while these indicators may change with the progression of the disease. In addition, several studies demonstrated that decreased hemoglobin levels in COVID-19 patients were associated with the severity of the disease. Moreover, thrombocytopenia, which is reported in 5%-40% of patients, is known to be associated with poor prognosis of the disease. COVID-19 can present with various hematologic manifestations. In this regard, accurate evaluation of laboratory indicators at the beginning and during COVID-19 can help physicians to adjust appropriate treatment and provide special and prompt care for those in need.  相似文献   
67.
AIM: To investigate the prevalence and risk factors of gastroesophageal reflux disease (GERD) symptoms in Qashqai migrating nomads with a different life style in Fars province, southern Iran. METHODS: In summer 2006, 748 Qashqai migrating nomads aged 25 years or more were enrolled using a multiple-stage stratified cluster random sampling method. A questionnaire consisting of demographic characteristics, lifestyle and GERD symptoms (heartburn, regurgitation, chest pain, dysphagia, hoarseness and cough) as completed for each subject. RESULTS: The questionnaire was completed in 717 subjects. The prevalence rate of GERD, defined as reflux occurring at least one time per week in the preceding year, was 33% (237 subjects). The prevalence was higher in older individuals (36.0% vs 28.9%, P 〈 0.05) and in those with other gastrointestinal complaints (51.0% vs 27.8%, P 〈 0.001), but not different in obese and non-obese subjects. It was also higher in those consuming fruits and vegetables more than once a week (36.2% vs 17.3%, P 〈 0.001). GERD had a positive correlation with smoking (42.1% vs 27.8%, P 〈 0.001), but a negative relation with non-alcoholic beverages. The association between GERD and non-steroidal antiinflammatory drugs (NSAIDs) consumption was also significant (40.2% vs 25.4%, P 〈 0.001). CONCLUSION: The prevalence of GERD (33%) is very high in Qashqai migrating nomads which may be due to a lower socioeconomic and educational level of these people and difference in the life style. Older age, frequent consumption of fruits and vegetables, smoking and NSAIDs are risk factors for GERD in this population.  相似文献   
68.
69.
BACKGROUND & AIMS: We conducted a systematic review and a meta-analysis to estimate the magnitude and determinants of association between diabetes and hepatocellular carcinoma (HCC). METHODS: MEDLINE searches were conducted for published full studies (between January 1966 and February 2005) that provided risk estimates and met criteria concerning the definition of exposure and outcomes. Two investigators independently performed standardized search and data abstraction. Unadjusted and adjusted odds ratios for individual outcomes were obtained or calculated for each study and were synthesized using a random-effects model. RESULTS: A total of 26 studies met our inclusion and exclusion criteria. Among 13 case-control studies, diabetes was associated significantly with HCC in 9 studies (pooled odds ratio, 2.5; 95% confidence interval, 1.8-3.5). Among 13 cohort studies, diabetes was associated significantly with HCC in 7 studies (pooled risk ratio, 2.5; 95% confidence interval, 1.9-3.2). The results were relatively consistent in different populations, different geographic locations, and a variety of control groups. The significant association between HCC and diabetes was independent of alcohol use or viral hepatitis in the 10 studies that examined these factors. Few studies adjusted for diet and obesity. CONCLUSIONS: Diabetes is associated with an increased risk for HCC. However, more research is required to examine issues related to the duration and treatment of diabetes, and confounding by diet and obesity.  相似文献   
70.
The antiaging effect of selegiline was reported by several investigators; therefore, there is a growing interest in the potential use of stem cell therapy in aging. In this investigation, selegiline was used to induce neuronal differentiation in undifferentiated pluripotent embryonic stem cells (ESCs). The results show that selegiline can induce neuronal phenotype associated with neurotrophic factor expression. Morphologic and immunohistochemical techniques were used to evaluate the differentiation of the CCE cells, Cresyl violet for the morphologic study, anti-synaptophysin and antityrosine hydroxylase antibodies for characterizing the neuronal phenotype of ESCs, and RT-PCR to study the neurotrophins. The results showed that selegiline can induce dose-dependent ESC differentiation into neurons. Moreover, selegiline can induce neurotrophin expression. This study suggests the potential use of combined selegiline and stem cell therapy to improve deficits in neurodegenerative diseases in aging.  相似文献   
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