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991.
John Werner  MD    Jocelyn A. Rapelyea  MD    Kristen G. Yost  MS    Rachel F. Brem  MD 《The breast journal》2009,15(6):579-582
Abstract:  To develop a means of quantifying axillary radio-tracer uptake in patients undergoing breast specific gamma imaging. This may help differentiate uptake secondary to extravasation of the radio-tracer at the injection from increased uptake as a result of breast cancer metastatic to lymph nodes. A retrospective analysis of patients who had undergone breast specific gamma imaging was performed. Scans from 26 patients showing increased axillary uptake of radio-tracer were identified from 939 patients reviewed. Eighteen of these patients had increased axillary uptake ipsilateral to the side of tracer injection in the absence of breast cancer on that side. Of these 18 cases, eight patients had pathologic proven axillary metastatic disease with increased axillary uptake contralateral to the side of tracer injection. The maximum signal intensity for each region of increased radio-tracer uptake was measured using the net maximum uptake per region of interest and the two groups of patients were compared. Statistical significance was determined using a two-tailed p-value and 95% confidence intervals were considered statistically significant. The calculated means of the "net maximum uptake per region of interest" in the subjects with increased radio-tracer uptake secondary to radio-tracer extravasation and metastatic breast cancer were 177.89 and 117.25, respectively. Comparison of the means yielded a two-tailed p-value of 0.0498, which is statistically significant. There is a statistically significant greater intensity of axillary radio-tracer uptake when the uptake occurs secondary to extravasation when compared with metastases to axillary lymph nodes.  相似文献   
992.
BACKGROUND: The chemokines keratinocyte-Derived Cytokine (KC) and macrophage inflammatory protein (MIP)-2, murine equivalents of human interleukin 8, have been implicated in remote injury after acute hind limb ischemia/reperfusion (I/R). These studies were designed to determine whether the cytokines responsible for remote tissue injury are also synthesized and accumulate in the ischemic or reperfused hind limb. METHODS: B6, 129SF2/J mice were subjected to either 3 hours of unilateral hind limb ischemia alone (IA) or 3 hours of ischemia followed by 4 or 24 hours of reperfusion (I/R). After IA or I/R, experimental and control (nonischemic) contralateral hind limbs were harvested for analysis of protein content, messenger RNA (mRNA), tissue edema, and viability. RESULTS: IA did not increase KC or MIP-2 mRNA or protein levels. In contrast, I/R resulted in a 15- and 10-fold increase in KC mRNA after 4 and 24 hours of reperfusion, respectively. KC protein levels were increased 10-fold after 4 hours of reperfusion and 30-fold after 24 hours (vs IA or sham; P < .001). MIP-2 mRNA transiently increased 42-fold after 4 hours of reperfusion but decreased to basal levels after 24 hours of reperfusion. Despite the relative increase in MIP-2 mRNA by 4 hours of reperfusion, significantly increased (8- to 10 fold) MIP-2 protein levels were not detected until 24 hours of reperfusion only in the reperfused limbs. Tissue edema was increased significantly (P < .01) compared with sham after just 4 hours of reperfusion and remained increased at 24 hours. Tissue viability decreased 52% after 4 hours of reperfusion and did not change significantly by 24 hours. CONCLUSIONS: Skeletal muscle is a site of significant ongoing chemokine synthesis during reperfusion. The persistent increase in muscle chemokine levels at 24 hours of reperfusion was not associated with increased edema or injury. The role of these chemokines during reperfusion may be further investigated by local or oral administration of chemokines or chemokine receptor antagonists. CLINICAL RELEVANCE: I/R injury remains an important clinical problem across a variety of surgical specialties. In the critical care arena, serum levels of proinflammatory cytokines have been useful in predicting the mortality associated with acute respiratory distress syndrome and sepsis. In this article, the data presented indicate that murine skeletal muscle produces potent proinflammatory neutrophil and macrophage chemokines during reperfusion, but not during ischemia. These findings suggest that measurement of tissue and/or serum levels of chemokines during reperfusion may be an important adjunct to predicting tissue injury along with ongoing inflammation during the clinical course of reperfusion injury. Within the vascular system, severe inflammatory responses are usually associated with thrombotic events. New techniques to noninvasively image thrombin activation (by using magnetic resonance imaging) in reperfused limbs may coincide with the pattern of murine skeletal muscle chemokine expression in humans. The data suggest that reperfusion is when chemokine mRNA and protein synthesis increase. Within the time periods studied in these experiments, the chemokine component of the inflammatory response remained in the reperfused, rather than the systemic nonreperfused, tissue. This observation may underestimate the degree of the systemic response to ischemia because the single mouse hind limb represents only 7% of the mouse total body area, whereas the human limb represents nearly 18% of the adult body area. Despite this shortcoming, these data provide potential temporal and quantitative information regarding the location and magnitude of chemokine synthesis in skeletal muscle during reperfusion.  相似文献   
993.
Background Metastatic breast cancer is an aggressive disease associated with recurrence and decreased survival. To improve outcomes and develop more effective treatment strategies for patients with breast cancer, it is important to understand the molecular mechanisms underlying metastasis. Methods We used allelic imbalance (AI) to determine the molecular heritage of primary breast tumors and corresponding metastases to the axillary lymph nodes. Paraffin-embedded samples from primary breast tumors and matched metastases (n = 146) were collected from 26 patients with node-positive breast cancer involving multiple axillary nodes. Hierarchical clustering was used to assess overall differences in the patterns of AI, and phylogenetic analysis inferred the molecular heritage of axillary lymph node metastases. Results Overall frequencies of AI were significantly higher (P < 0.01) in primary breast tumors (23%) than in lymph node metastases (15%), and there was a high degree of discordance in patterns of AI between primary breast carcinomas and the metastases. Metastatic tumors in the axillary nodes showed different patterns of chromosomal changes, suggesting that multiple molecular mechanisms may govern the process of metastasis in individual patients. Some metastases progressed with few genomic alterations, while others harbored many chromosomal alterations present in the primary tumor. Conclusions The extent of genomic heterogeneity in axillary lymph node metastases differs markedly among individual patients. Genomic diversity may be associated with response to adjuvant therapy, recurrence, and survival, and thus may be important in improving clinical management of breast cancer patients.  相似文献   
994.
Background: Aprotinin is the only Food and Drug Administration-approved agent to reduce haemorrhage related to cardiac surgery and its safety and efficacy has been extensively studied. Our study sought to compare the efficacy, early and late mortality and major morbidity associated with aprotinin compared with e-aminocaproic acid (EACA) in cardiac surgery operations. Methods: Between January 2002 and December 2006, 2101 patients underwent coronary artery bypass grafting (CABG), valve surgery or CABG and valve surgery in our institution with the use of aprotinin (1898 patients) or EACA (203 patients). Logistic regression and propensity score analysis were used to adjust for imbalances in the patients’ preoperative characteristics. The propensity score-adjusted sample included 570 patients who received aprotinin and 114 who received EACA (1–5 matching). Results: Operative mortality was higher in the aprotinin group in univariate (aprotinin 4.3% vs EACA 1%, p = 0.023) but not propensity score-adjusted multivariate analysis (4% vs 0.9%, p = 0.16). In propensity score-adjusted analysis, aprotinin was also associated with a lower rate of blood transfusion (38.8% vs 50%, p = 0.04), a lower rate of haemorrhage-related re-exploration (3.7% vs 7.9%, p = 0.04) and a higher risk of in-hospital cardiac arrest (3.7% vs 0%, p = 0.03) and a marginally but not statistically significantly higher risk of acute renal failure (6.8% vs 2.6%, p = 0.09). In Cox proportional hazards regression analysis, the risk of late death was higher in the aprotinin compared to EACA group (hazard ratio = 4.33, 95% confidence interval (CI) = 1.60–11.67, p = 0.004). Conclusion: Aprotinin decreases the rate of postoperative blood transfusion and haemorrhage-related re-exploration, but increases the risk of in-hospital cardiac arrest and late mortality after cardiac surgery when compared to EACA. Cumulative evidence suggests that the risk associated with aprotinin may not be worth the haemostatic benefit.  相似文献   
995.
BackgroundClinically relevant postoperative pancreatic fistula and delayed gastric emptying cause substantial morbidity after pancreatoduodenectomy. Per international guidelines, the placement of jejunostomy tubes may be considered for patients at risk for malnutrition, such as those with a high risk for clinically relevant postoperative pancreatic fistula and related complications. This study determined predictors and postoperative outcomes of jejunostomy tube placement.MethodsPatients undergoing pancreatoduodenectomy in 2014 to 2015 were identified using the American College of Surgeons National Surgical Quality Improvement Program and Procedure-Targeted Pancreatectomy Participant Use Files. Multivariable logistic regressions were used to identify factors associated with concurrent jejunostomy tube placement and postoperative outcomes.ResultsOf 3,600 patients, 8.9% underwent jejunostomy tube placement. Patients given a jejunostomy tube were more likely white (odds ratio 1.46, P = .016), to have low preoperative serum albumin levels (odds ratio 2.13, P < .001), to have received neoadjuvant radiotherapy (odds ratio 2.14, P < .001), and to have received an intraoperative transfusion (odds ratio 1.50, P = .004). We observed no association between jejunostomy tube placement and an increasing number of risk factors for clinically relevant postoperative pancreatic fistula (P = .96) or delayed gastric emptying (P = .54). Overall, jejunostomy tube placement was associated with increased morbidity (odds ratio 1.34, P = .020) and duration of stay (P < .001), but not mortality (P = .12). Among patients with low serum albumin or those who developed clinically relevant postoperative pancreatic fistula or delayed gastric emptying, jejunostomy tube utilization was not associated with morbidity or mortality.ConclusionJejunostomy tube placement during pancreatoduodenectomy was not driven by risk factors for clinically relevant postoperative pancreatic fistula or delayed gastric emptying, suggesting that practice patterns play a role. Among patients with at-risk preoperative albumin or who developed these complications, jejunostomy tube placement was not associated with worse outcomes, supporting selective utilization per guideline recommendations.  相似文献   
996.
Breast‐specific gamma imaging (BSGI) is a physiologic breast imaging modality that provides more sensitive detection of breast lesions than mammography or ultrasound, and appears to have greater specificity than breast MRI. The purpose of this study was to evaluate how often BSGI changed surgical management in patients with breast cancer. Charts were reviewed from 218 consecutive eligible patients who had preoperative evaluation with BSGI or MRI before surgery for breast cancer from January 2008 to May 2010. Patients who were initially considered eligible for breast‐conserving therapy (BCT) were evaluated to determine how many ultimately had mastectomies. Patients who underwent mastectomy because of personal choice or ineligibility for BCT were excluded. Management was changed to mastectomy in 11.9% of those who had BSGI and 28.9% of those who had MRI. Review of pathology demonstrated that all patients who underwent mastectomies were not candidates for breast conservation. 15.4% of patients who underwent BCT based on BSGI findings required a single re‐excision due to positive surgical margins. 14.4% required mastectomy. In the MRI group, 18.8% required a single re‐excision, and 6.3% required mastectomy. Evaluation with BSGI changed management to mastectomy in a substantial proportion of patients believed to be eligible for BCT following standard imaging. BSGI is effective in evaluation of extent of disease in patients with breast cancer, and is comparable to MRI in terms of its influence on surgical management.  相似文献   
997.
The High-Activity Arthroplasty Score (HAAS) was specifically developed to assess subtle variations in functional ability after lower limb arthroplasty with particular regard to highly functioning individuals. The score was a 4-item self-assessment measure covering the 4 domains of walking, running, stair climbing, and general activities, with a possible score ranging from 0 to 18 points. The score was validated in 22 patients (total hip arthroplasty [THA], n = 11; total knee arthroplasty [TKA], n = 11) by comparison with the Oxford, Knee Society, Harris Hip, and Short WOMAC scores. The HAAS was then administered to 152 high-functioning arthroplasty patients (THA, n = 99; TKA, n = 53), all younger than 66 years. The HAAS produced a much wider range of scores, allowing greater differentiation of level of function between patients in assessing performance after TKA or THA.  相似文献   
998.

Objective

Thoracic endovascular aortic repair (TEVAR) has demonstrated encouraging results and is gaining increasing acceptance as a treatment option for aortic aneurysms and dissections. Yet, its role in managing proximal aortic pathologies is unknown—this is important because in proximal (Stanford type A) aortic dissections, 10% to 30% are not accepted for surgery and 30% to 50% are technically amenable for TEVAR. We describe our case series of type A aortic dissections treated by using TEVAR.

Methods

Between year 2009 and 2016, 12 patients with acute, subacute, or chronic type A aortic dissection with the proximal entry tear located between the coronaries and brachiocephalic artery were treated with TEVAR at 3 centers. Various stent-graft configurations were used to seal the proximal entry tear in the ascending aorta under rapid pacing.

Results

A total of 12 patients (9 male, 3 female), mean age 81 ± 7 years, EuroSCORE II 9.1 ± 4.5, underwent TEVAR for the treatment of type A aortic dissection. Procedural success was achieved in 11 of 12 patients (91.7%). There was 1 minor stroke and 1 intraprocedural death. No additional deaths were reported at 30 days. At 36 months, there were 4 further deaths (all from nonaortic causes). The mean survival of these 4 deceased was 23 months (range 15-36 months). Follow-up computed tomography demonstrated favorable aortic remodeling.

Conclusions

TEVAR is feasible and reveals promising early results in selected patients with type A aortic dissection who are poor candidates for surgical repair. The current iteration of stent-graft technology, however, needs to be adapted to features specific to the ascending aorta.  相似文献   
999.
1000.
miR-155 is an oncogenic microRNA which is upregulated in many solid cancers. The targets of miR-155 are well established, with over 100 confirmed mRNA targets. However, the regulation of miR-155 and the basis of its upregulation in cancer is not well understood. We have previously shown that miR-155 is regulated by p63, and here we investigate the role of the major p63 isoforms TAp63 and ΔNp63 in this regulation. When the TAp63 isoform was knocked down, or exogenously overexpressed, miR-155 levels were elevated in response to TAp63 knockdown or reduced in response to TAp63 overexpression. The ΔNp63 isoform is shown to directly bind to the p63 response element on the miR-155 host gene, and this binding is enriched when TAp63 is knocked down. This could indicate that TAp63 prevents ΔNp63 from binding to the miR-155 host gene. The knockdown of TAp63, and the subsequent elevation of miR-155, enhances migration and tumour growth similar to that seen when directly overexpressing miR-155. The migratory phenotype is abrogated when miR-155 is inhibited, indicating that miR-155 is responsible for the phenotypic effect of TAp63 knockdown.  相似文献   
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