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121.
Rationale, aims and objectives Drug‐eluting coronary stents (DES) rapidly dominated the marketplace in the United States after approval in 2003, but utilization rates were initially lower among African American patients. We assess whether racial differences persisted as DES diffused into practice. Methods Medicare claims data were used to identify coronary stenting procedures among elderly patients with acute coronary syndromes (ACS). Regression models of the choice of DES versus bare mental stent controlled for demographics, ACS type, co‐morbidities and hospital characteristics. Diffusion was assessed in the short run (2003–2004) and long run (2007), with the effect of race calculated to allow for time‐varying effects. Results The sample included 381 887 Medicare beneficiaries treated with stent insertion; approximately 5% were African American. Initially (May 2003–February 2004), African American race was associated with lower DES use compared to other races (44.3% versus 46.5%, P < 0.01). Once DES usage was high in all patients (March–December 2004), differences were not significant (79.8% versus 80.3%, P = 0.45). Subsequent concerns regarding DES safety caused reductions in DES use, with African Americans having lower use than other racial groups in 2007 (63.1% versus 65.2%, P < 0.01). Conclusions Racial disparities in DES use initially disappeared during a period of rapid diffusion and high usage rates; the reappearance of disparities in use by 2007 may reflect DES use tailored to unmeasured aspects of case mix and socio‐economic status. Further work is needed to understand whether underlying differences in race reflect decisions regarding treatment appropriateness.  相似文献   
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BACKGROUND: Several instruments can be used to identify patients with an unfavourable course of low back pain in general practice. However, it is unclear which instrument is the predictor of outcome. AIM: To compare the predictive performance (that is, calibration and discrimination) of risk estimation by GPs with assessments using the Orebro Musculoskeletal Pain Screening Questionnaire, the Low Back Pain Perception Scale (LBPPS), and a prediction rule developed for this purpose. Design of study: A prospective cohort study with 1-year follow-up. SETTING: General practice in The Netherlands. METHOD: The outcome 'unfavourable course of low back pain' was defined as having no clinically important improvement at minimally 50% of the measurements at 6, 13, 26, and 52 weeks. Logistic regression analyses were used to study associations between potential predictors and outcome. RESULTS: In total, 60 GPs recruited 314 patients to the study (16 patients were excluded from analysis due to missing data on the course of low back pain). Over a third of patients (112/298) showed an unfavourable course of low back pain on follow-up. Risk estimation by GPs, the Orebro questionnaire, the LBPPS, and the prediction rule had discriminative ability (area under the curve) of 0.59 (95% CI [confidence intervals] = 0.52 to 0.66); 0.61 (95% CI = 0.54 to 0.67); 0.59 (95% CI = 0.52 to 0.66); and 0.75 (95% CI = 0.69 to 0.81) respectively. The prediction rule included history of low back pain, self-perceived risk to develop chronic low back pain, no solicitous responses of the patient's partner (as reported by the patient), frequent walking at work, and 'pain catastrophising'. CONCLUSION: Although the prediction rule performed best with regard to calibration and discrimination, it needs to be externally validated. Risk estimation by GPs performs as well as other instruments and, at present, seems to be the best available option.  相似文献   
124.
Chemerin is an adipokine that regulates adipogenesis and metabolic functions of mature adipocytes mainly through the activation of chemokine‐like receptor 1 (CMKLR1). Elevated levels of chemerin have been found in individuals with obesity, type 2 diabetes, and osteoporosis. This adipokine was identified as an inflammatory and metabolic syndrome marker. Considering that the association between metabolic syndrome and bone health remains unclear, the present study aimed to clarify the role of chemerin in the pathophysiology of bone loss induced by dyslipidemia, particularly modulating osteoclastogenesis. In vitro analyses showed a downregulation of CMKLR1 at the early stage of differentiation and a gradual increase at late stages. Strikingly, chemerin did not modify osteoclast differentiation markers or osteoclast formation; however, it increased the actin‐ring formation and bone resorption activity in mature osteoclasts. The increased bone resorption activity induced by chemerin was effectively inhibited by CMKLR1 antagonist (CCX832). Chemerin boosting mature osteoclast activity involves ERK5 phosphorylation. Moreover, two models of dyslipidemia (high‐fat diet [HFD]‐treated C57/BL6 and db/db mice) exhibited significantly increased level of chemerin in the serum and gingival tissue. Morphometric analysis showed that HFD‐treated and db/db mice exhibited increased alveolar bone loss compared to respective control mice, which was associated with an up‐regulation of chemerin, CMKLR1 and cathepsin K mRNA expression in the gingival tissue. The treatment of db/db mice with CCX832 effectively inhibited bone loss. Antagonism of chemerin receptor also inhibited the expression of cathepsin K in the gingival tissue. Our results show that chemerin not only increases osteoclasts activity in vitro, but also that increased level of chemerin in dyslipidemic mice plays a critical role in bone homeostasis. © 2016 American Society for Bone and Mineral Research.  相似文献   
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We sought to evaluate whether residency application statements regarding expected career paths are accurate predictors of early postresidency career paths. We evaluated 162 residents who completed a categorical medicine residency at Georgetown University Hospital between 1990 and 1998 to determine if their stated career plans (generalist practice, subspecialization, or undecided) at application predicted activity immediately after residency. Of 130 residents with defined postresidency plans at application, most 78 (60%) followed those career paths after graduation; 18 (67%) of 27 pursued their initial interest in generalist practice, and 60 (58%) of 103 pursued their stated interest in subspecialty training. We also noted a movement of residents toward generalism (79 [49%] of 162), despite low initial interest (27 [17%] of 162).  相似文献   
127.
Our contribution reviews the diagnostic algorithm of head injuries in children. According to the Heidelberg consensus on head injury, patients should be divided into three risk groups. In low-risk patients clinical observation is the method of choice and radiological examinations are usually unnecessary. Patients at medium risk should be observed carefully. Sometimes neurosurgical consultation or CT is necessary. High risk patients in most instances need CT and neurosurgical consultation. Skull X-ray is helpful only in selected cases. A simple fracture as demonstrated by skull X-ray has no therapeutic consequence. However, normal findings in skull X-ray do not exclude intracranial injury. CT is the method of choice to detect intracranial hemorrhage, epi- or subdural hematoma and cerebral contusion. If patients present with severe clinical deficits, CT allows characterization of lesions and initiation of specific therapy.  相似文献   
128.
Purpose of ReviewWith increased understanding of the biomechanical function of the acetabular labrum, more attention has been directed towards surgical techniques that preserve or restore normal joint anatomy. While labral repair has been shown to produce superior outcomes to labral debridement, repair is not always possible in the setting of severe labral intrasubstance tearing or deficiency. These patients were previously left without suitable arthroscopic treatment options.Recent FindingsLabral reconstruction is an emerging procedure that has been shown to offer promising outcomes for traditionally difficult-to-treat hip pathology. Short- and mid-term follow-up studies have consistently demonstrated significant improvement in patient-reported outcomes, function, and patient satisfaction postoperatively, often despite less favorable preoperative characteristics.SummaryLabral reconstruction is a viable arthroscopic treatment option that has been shown to reliably produce clinically meaningful results in patients with severe labral pathology that is not amenable to repair/refixation or augmentation.  相似文献   
129.
Abdominal trauma: use of oral contrast material for CT is safe   总被引:2,自引:0,他引:2  
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130.
Color Doppler imaging (CDI) can demonstrate the relative direction and velocity of blood flow in color, superimposed on a conventional gray-scale ultrasound image that depicts stationary tissue. Twenty-five infants were studied with portable CDI in the coronal, sagittal, and axial planes. Bilateral antegrade flow was noted in the anterior, middle, and posterior cerebral arteries in all patients. Multiplanar CDI can image flow in the circle of Willis and its tributaries and branches.  相似文献   
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