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111.
We investigated the relationship between immunological and behavioral changes during ageing in Dark Agouti female rats. Results showed that ageing was associated with decreased exploratory behavior and increased emotionality (open field test) and decreased pain perception (writhing assay), but not with altered depression-like behavior (forced swim test). The observed behavioral changes were paralleled with decreased innate immunity in middle-aged and old rats, as revealed by reduced peroxide production of peritoneal macrophages; and decreased specific immunity, measured by the plaque-forming cell response, in old rats in comparison with young rats. Correlation analyses between behavioral and immune parameters demonstrated a significant correlation between the lines crossed in the open field test and the plaque-forming cell response. Taken together, the demonstrated age-dependent association between exploratory behavior and specific immune response suggests a senescent decline of a common neuroimmune regulatory mechanism.  相似文献   
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BACKGROUND: The established treatment modality of acute Stanford type A dissection includes repair of the ascending aorta and various portions of the aortic arch, whereas the descending aorta is left untreated. We report a simultaneous approach of open repair of the ascending aorta with transluminal stent grafting of the descending aorta to minimize the consequences of an untreated descending aorta. METHODS: From April 2001 to February 2002, 8 consecutive patients (3 women [37.5%] and 5 men [62.5%]) with a mean age of 55.7 years (range, 45 to 70 years) were intended to be treated with the combined method of surgical repair of the ascending aorta and transluminal stent grafting into the descending aorta during the period of deep hypothermic circulatory arrest. Circulatory arrest time ranged between 30 and 67 minutes (average, 38.8 minutes). Specially designed Talent stent grafts (32 to 40 mm in diameter, length 13 cm) were inserted under direct vision and deployed with the proximal end at the origin of the left subclavian artery. RESULTS: Intraoperative stent graft placement was successful in 7 patients (87.5%). Because of severe kinking of the distal arch, stent insertion failed in 1 patient (12.5%). One patient with a history of preoperative stroke in the middle cerebral artery died because of intracerebral bleeding on postoperative day 2, resulting in an in-hospital mortality of 12.5%. Mean intensive care unit stay was 6.4 days (range, 2 to 21 days) and overall hospital stay was 18.2 days (range, 7 to 33 days). Completion computed tomographic scans revealed complete thrombosis of the false lumen in 2 patients and partial thrombosis in 4 patients. Follow-up was complete and ranged from 1 to 9 months (mean, 5.4 months). CONCLUSIONS: This preliminary study shows that combined surgical and endovascular treatment of acute type A dissection is feasible, and at least partial thrombosis of the false lumen can be achieved, potentially minimizing the risk of further dilatation or rupture. Additionally, the stent graft expands the otherwise sickle-shaped true lumen, thereby ameliorating distal aortic perfusion. Long-term results are warranted to demonstrate the effectiveness of this new combined treatment modality.  相似文献   
114.
BACKGROUND: The VAC system (vacuum-assisted wound closure) is a noninvasive active therapy to promote healing in difficult wounds that fail to respond to established treatment modalities. The system is based on the application of negative pressure by controlled suction to the wound surface. The method was introduced into clinical practice in 1996. Since then, numerous studies proved the effectiveness of the VAC System on microcirculation and the promotion of granulation tissue proliferation. METHODS: Eleven patients (5 men, 6 women) with a median age of 64.4 years (range 50 to 78 years) with sternal wound infection after cardiac surgery (coronary artery bypass grafting = 5, aortic valve replacement = 5, ascending aortic replacement = 1) were fitted with the VAC system by the time of initial surgical debridement. RESULTS: Complete healing was achieved in all patients. The VAC system was removed after a mean of 9.3 days (range 4 to 15 days), when systemic signs of infection resolved and quantitative cultures were negative. In 6 patients (54.5%), the VAC system was used as a bridge to reconstructive surgery with a pectoralis muscle flap, and in the remaining 5 patients (45.5%), primary wound closure could be achieved. Intensive care unit stay ranged from 1 to 4 days (median 1 day). Duration of hospital stay varied from 13 to 45 days (median 30 days). In-hospital mortality was 0%, and 30-day survival was 100%. CONCLUSIONS: The VAC system can be considered as an effective and safe adjunct to conventional and established treatment modalities for the therapy of sternal wound infections after cardiac surgery.  相似文献   
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It was the aim of this study to compare in vitro closure time (PFA-100), reflecting platelet-related primary hemostasis, to more platelet-specific tests like whole blood electrical aggregometry and platelet surface antigen expression in healthy volunteers. In vitro closure time was measured using a PFA-100. Platelet surface antigen expression (CD63, CD62-P, CD42b, CD36, CD31) was determined in accordance with the consensus protocol for flow-cytometric characterisation of platelet function. Platelet aggregometry was performed using a whole blood electrical aggregometer (ADP and arachidonic acid as agonists). Analysis of the obtained data revealed only a few significant correlations between the different platelet function tests used. This finding can be explained by the various aspects of platelet function being focused by these tests in different extents. Whenever platelet function is analysed, the investigator should be aware of the specific and limited evidence of the method used. For screening purposes, it may be useful to introduce a platelet function index, referring to basal platelet activity, platelet adhesion and platelet aggregation at low and high shear stress forces.  相似文献   
117.
Churg-Strauss syndrome (CSS) is medium blood vessels vasculitis with predilection for lungs in patients with bronchial asthma, chronic eosinophilic pneumonia and positive ANCA in the sera in 55-67%. This is a case report of a 60 years old female patient with bronchial asthma, peripherial pulmonary infiltrations, blood eosinophilia, xerophtalmia, tachycardia, chronic rhinosinustis, polyneuropathia and negative imunological tests: CIC (PEG), CRYO, ANA (IIF), RF (aglutination) and ANCA (IFF: pANCA and cANCA; ELISA: proteinase 3, lactoferrin, myeloperoxidase. elastase, cathepsin G). Eosinophilic infiltrates in the tissues tested by skin and salivery gland biopsies were not found. The patient had fulfilled five clinical diagnostic criteria and responded well to imunosuppressive therapy, so this case could be classified as the ANCA negative angiitis and granulomatosis of CSS type.  相似文献   
118.
Course and kinetics of the isothermal bulk polymerization of methyl methacrylate were studied by differential scanning calorimetry. The initiator used was 2,2′-azoisobutyronitrile. The polymerization was investigated at temperatures between 70 and 90°C at constant initiator concentration, 5,2.10?2 mol dm?3. The heat of polymerization at 70°C is ?52,3 kJ/mol (?12,5 kcal/mol) and decreases, i.e. becomes more negative, with increasing temperature. Initial rate constants for the polymerization were also determined and from them the overall activation energy, 77 kJ/mol (18,4 kcal/mol), which is in good agreement with the literature value. Another series of polymerization experiments were performed at 80°C with variable amounts of the initiator. The heat of polymerization found is ?52,8 kJ/mol (?12,6 kcal/mol) and depends only slightly on the initiator concentration. The overall rate of polymerization at low degrees of conversion depends on the square root of the initiator concentration. These findings thus corroborate the conclusion reached by other authors that differential scanning calorimetry is a useful method for studying the kinetics of polymerization.  相似文献   
119.
The present work analyzed the gene pattern profiles in 6 squamous non-small cell lung cancers (NSCLCs) versus 4 normal lung epithelial tissues by means of cDNA microarrays. In addition to cDNA microarray analyses, quantitative RT-PCR and immunohisto-chemical analyses were used to validate some of the results obtained. Our data enabled 7 genes to be selected by looking at the genes which were detected as being expressed in all the tumors and not expressed in all the normal samples, or inversely. Additionally, 19 genes were detected as being overexpressed in the tumors when compared to the normal tissue specimens. Of these 26 genes, 16 are not yet suspected of influencing NSCLC biology. These genes are involved in cell proliferation (G2 cyclin), signal transduction (SMARCC2, TM4SF3), apoptosis (CFLAR/FLIP), cell cytoskeleton (cytokeratins-14 and 16, alpha-tubulin isoform 1 and S100A10), cell adhesion (JUP), invasion (cathepsins H and O) and other biological processes (OAZ1, IGHG3, SCYA5/RANTES, beta-sarcoglycan and transcobalamin I). In conclusion, we identified a number of genes as being differentially expressed in squamous NSCLCs as compared to normal lung epithelial tissue. Some of these genes (such as those involved in invasion) could be used as new prognostic markers and others, like CFLAR/FLIP, could even constitute new therapeutic targets.  相似文献   
120.
The overexpression of somatostatin receptors (SST-Rs) on various tumour cells provides the molecular basis for the successful use of radiolabelled SST analogues in clinical oncology. The objective of the study was to evaluate the tumour binding of In-1,4,7,10-tetraazacyclo-dodecane-N,N',N',N'-tetraacetic acid-lanreotide (In-DOTA-LAN) and In-DOTA-tyrosine-octreotide (In-DOTA-Tyr-OCT) in patients with stage IV melanoma. In addition, we evaluated the potential antiproliferative effect of SST analogues, together with an assessment of the functionality of SST-Rs, on four melanoma cell lines. Twenty-three patients with advanced metastatic melanoma underwent scintigraphy. Thirty-eight of 61 lesions (62%) were positively imaged with In-DOTA-LAN, whereas 23 (37%) were negative. With In-DOTA-Tyr-OCT, 10 of the 23 documented lesions (43%) were positive and 13 (56%) were negative. In vitro, cell lines showed no growth inhibition in the presence of SST analogues and no influence on cell cycle distribution was found with the addition of SST analogues to cultured cells. In addition, no functional surface SST-Rs could be demonstrated on these cell lines. Taken together, our results demonstrate the visualization of metastatic melanoma in a high percentage of patients, probably due to binding of SST analogues to SST-Rs on tumour vessels or infiltrating immune cells. Judging from our data, however, there is no evidence of functional SST-R expression on melanoma cells.  相似文献   
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