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91.
Most fragility fractures arise among the many women with osteopenia, not the smaller number with osteoporosis at high risk for fracture. Thus, most women at risk for fracture assessed only by measuring areal bone mineral density (aBMD) will remain untreated. We measured cortical porosity and trabecular bone volume/total volume (BV/TV) of the ultradistal radius (UDR) using high‐resolution peripheral quantitative computed tomography, aBMD using densitometry, and 10‐year fracture probability using the country‐specific fracture risk assessment tool (FRAX) in 68 postmenopausal women with forearm fractures and 70 age‐matched community controls in Olmsted County, MN, USA. Women with forearm fractures had 0.4 standard deviations (SD) higher cortical porosity and 0.6 SD lower trabecular BV/TV. Compact‐appearing cortical porosity predicted fracture independent of aBMD; odds ratio (OR) = 1.92 (95% confidence interval [CI] 1.10–3.33). In women with osteoporosis at the UDR, cortical porosity did not distinguish those with fractures from those without because high porosity was present in 92% and 86% of each group, respectively. By contrast, in women with osteopenia at the UDR, high porosity of the compact‐appearing cortex conferred an OR for fracture of 4.00 (95% CI 1.15–13.90). In women with osteoporosis, porosity is captured by aBMD, so measuring UDR cortical porosity does not improve diagnostic sensitivity. However, in women with osteopenia, cortical porosity was associated with forearm fractures. © 2014 American Society for Bone and Mineral Research.  相似文献   
92.
The purpose of this study was to evaluate patient, operative, implant, surgeon, and hospital factors associated with aseptic revision after primary THA in patients registered in a large US Total Joint Replacement Registry. A total of 35,960 THAs registered from 4/2001–12/2010 were evaluated. The 8-year survival rate was 96.7% (95% CI 96.4%–97.0%). Females had a higher risk of aseptic revision than males. Hispanic and Asian patients had a lower risk of revision than white patients. Ceramic-on-ceramic, ceramic-on-conventional polyethylene, and metal-on-conventional polyethylene bearing surfaces had a higher risk of revision than metal-on-highly cross-linked polyethylene. Body mass index, health status, diabetes, diagnosis, fixation, approach, bilateral procedures, head size, surgeon fellowship training, surgeon and hospital volume were not revision risk factors.  相似文献   
93.
In this article we outline the molecular findings of select odontogenic tumors. In each section, we briefly review selected the clinicoradiographic, histologic, immunologic features, focusing on the molecular findings and their applications in practice. The understanding of molecular pathobiology at various other organ sites has developed quite rapidly in recent years, however much remains unknown about the genetic profile of odontogenic tumors. Improved understanding of mutations in odontogenic tumors may clarify classification schema and elucidate targets for novel therapies. Molecular testing will no doubt improve our understanding of odontogenic tumor pathogenesis and will likely be, someday, an important component of routine clinical practice and its role will only increase in the coming years.  相似文献   
94.

INTRODUCTION

Thrombosis of the inferior vena cava (IVC) is governed by Virchow''s triad of stasis of blood flow, endothelial damage and hypercoagulability. Causes may be secondary to malignancy, congenital anomalies or other infrequent events such as external compression. We present a case of external compression of the IVC leading to extensive thrombus burden secondary to a benign hepatic cyst.

PRESENTATION OF CASE

A 72 year old African American female presented to the emergency department with new onset shortness of breath, right lower extremity weakness and swelling. CT imaging demonstrated multiple hepatic cysts compressing the IVC, leading to extensive clot burden. Treatment with heparin drip was initiated without resolution of her symptoms. Transcatheter mechanical thrombectomy and tPA infusion was performed. After 24 h, swelling and weakness were nearly resolved. The patient was bridged to therapeutic low molecular weight heparin in preparation for surgery.

DISCUSSION

Management of IVC thrombosis has typically been with a heparin drip and transition to oral anticoagulants. Thrombolysis has been shown to promote complete clot lysis more often than compared to standard anticoagulant therapy. In addition, venous patency was better maintained.

CONCLUSION

We feel that the added benefit of short term effects of improved venous patency and long term benefits of less post thrombotic syndrome, catheter based tPA administration and mechanical thrombectomy for thrombus offers an adjuvant treatment in the setting of large clot burden refractory to standard treatment.  相似文献   
95.
The practice of midwifery has long been recognized as both art and science. However, educational programmes for midwifery are most often undertaken within an academic health sciences environment, and tend to be based on knowledge derived from the sciences (e.g. life sciences, biomedical sciences, behavioural sciences and social sciences). These scientific perspectives, while essential to the preparatory and on-going education of midwives, do not necessarily fully prepare midwives to fulfil their practice roles. This paper reports a teaching innovation aimed at facilitating student exploration of fundamental, complex and ethereal concepts which are essential to the effective and skillful practice of midwifery. Through the exploration of the arts and humanities, students were encouraged to engage with concepts such as 'caring', 'empathy', 'suffering', 'motherhood', 'pain', 'love', 'attachment', 'health' and 'illness'. Students were also encouraged to explore cultural and social symbols pertaining to parenthood and family life. Evaluation revealed that students valued the course, and that they gained insights which assisted them to develop understanding of key concepts. Implications for practice and education are drawn from this paper.  相似文献   
96.
Aims and objectives. To investigate the factors that influence satisfaction with emergency care among individuals accompanying patients to the emergency department and explore agreement between the triage nurse and accompanying person regarding urgency. Background. Many patients seeking treatment in hospital are escorted by an accompanying person, who may be a friend, family member or carer. Several factors influence patient satisfaction with emergency care, including waiting time and time to treatment. It is also influenced by provision of information and interpersonal relations between staff and patients. Research on satisfaction has focused on the patient perspective; however, individuals who accompany patients are potential consumers. Knowledge about the ways accompanying persons perceive the patient's medical condition and level of urgency will identify areas for improved patient outcomes. Design and methods. A prospective cross‐sectional survey with a consecutive sample (n = 128 response rate 83·7%) was undertaken. Data were collected in an Australian metropolitan teaching hospital with about 32,000 visits to the emergency department each year. The Consumer Emergency Satisfaction Scale was used to measure satisfaction with nursing care. Results. Significant differences in perceptions of patient urgency between accompanying persons and nurses were found. Those people accompanying patients of a higher urgency were significantly more satisfied than those accompanying patients of a lower urgency. These results were independent of real waiting time or the accompanying person's knowledge of the patients’ triage status. In addition, older accompanying persons were more satisfied with emergency care than younger accompanying persons. Discussion. Little attention has been paid to the social interactions that occur between nurses and patients at triage and the ways in which these interactions might impact satisfaction with emergency care. Relevance to clinical practice. Good interpersonal relationships can positively influence satisfaction with the emergency visit. This relationship can contribute to improved patient care and health outcomes.  相似文献   
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Self-paced functional MR imaging (fMRI) paradigms, in which the task timing is determined by the subject's performance, can offer several advantages over commonly applied paradigms with predetermined stimulus timing. Independent component analysis (ICA) does not require specification of a timed response function, and could be an advantageous method of deriving results from fMRI data sets with varying response timings and durations. In this study normal volunteers (N = 10) each performed two self-paced fMRI motor and arithmetic paradigms. Individual data sets were analyzed with the Infomax spatial ICA algorithm. Conventional regression analysis was performed for comparison purposes. Spatial ICA effectively produced task-related components from each of the self-paced data sets, even in a few cases where regression analysis yielded non-specific functional maps. For the motor paradigm, these components consistently mapped to primary motor areas. ICA of the arithmetic paradigm yielded multiple task-related components that variably mapped to regions of parietal and frontal lobes. Regression analysis generally yielded similar spatial maps. The multiple task-related ICA components that were sometimes produced from each self-paced data set can be challenging to identify and evaluate for significance. These preliminary results indicate that ICA is useful as an exploratory and complementary method to conventional regression analysis for fMRI of self-paced paradigms.  相似文献   
100.
The Amplicor Chlamydia trachomatis test is a polymerase chain reaction (PCR)-based methodology used for the detection of a cryptic plasmid found in C. trachomatis. It was evaluated in comparison with cell culture and the Microtrak II Chlamydia enzyme immunoassay (EIA) for the detection of C. trachomatis in urogenital specimens from women. Endocervical swabs were collected from 993 women attending the women's unit at the Mount Sinai Hospital in Toronto. In addition, concomitant first void urine specimens were collected from 394 of these women for PCR testing only. As compared with culture of the endocervical specimens, PCR and EIA had a sensitivity, specificity, positive predictive value and negative predictive value of 84.6%, 99.2%, 57.9%, and 99.8% and 61.5%, 99.7%, 72.7%, and 99.5%, respectively. As compared with the secondary gold standard of a positive culture and/or a positive PCR using a primer to the major outer membrane protein the sensitivity, specificity, positive, and negative predictive values for culture were 72.2%, 100%, 100%, and 99.5%, respectively. For the Amplicor PCR and EIA the results were 88.9%, 99.7%, 84.2%, and 99.9% and 61.1%, 99.9%, 91.7%, and 99.6%, respectively. When the urine PCR was compared with the same standard, the test had a sensitivity of 91.7% and a specificity of 99.5%. Based on this study the Amplicor C. trachomatis test was found to be sensitive and specific for the detection of C. trachomatis in both endocervical and urine specimens.  相似文献   
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