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Periosteal Ewing sarcoma   总被引:3,自引:0,他引:3  
  相似文献   
23.
OBJECTIVE: To assess ischemia and reperfusion (I/R) injury in a hemihepatectomy model in pigs after prolonged continuous or intermittent vascular inflow occlusion in the liver. SUMMARY BACKGROUND DATA: Massive intraoperative blood loss during liver resections can be prevented by temporary vascular inflow occlusion, consequently leading to ischemia and reperfusion injury in the remnant liver. Previously, in a pig liver resection model in which only limited I/R injury was induced during brief (90 min) vascular inflow occlusion, the authors demonstrated reduced I/R injury after continuous (CNT) occlusion, compared to intermittent (INT). This liver resection study on pigs was undertaken to assess I/R injury after prolonged (120 min) CNT or INT occlusion. METHODS: In pigs (37.0 +/- 1.5 kg), liver ischemia during 2 hours was CNT (n = 6) or INT (n = 6) (eight subsequent periods of 12 min ischemia and 3 min recirculation), followed by 6 hours of reperfusion. A left hemihepatectomy (45.5% +/- 1.4%) was performed within the first 12 minutes of ischemia. No hepatic pedicle clamping or liver resection was performed in control experiments (n = 6). Microvascular damage was assessed by hyaluronic acid (HA) uptake capacity of the liver (parameter of early sinusoidal endothelial cell damage) and restoration of intrahepatic tissue pO2 during reperfusion. Hepatocellular damage was tested by plasma concentrations of aspartate aminotransferase (AST), alanine aminotransferase, and lactate dehydrogenase (LDH). RESULTS: Hyaluronic acid uptake after 6 hours of reperfusion, compared to preischemic uptake, was unaltered in the control group, but was significantly reduced in both resection groups. However, more HA was taken up after INT occlusion, compared to CNT (60.4% +/- 5.6% and 39.5% +/- 3.7%, respectively; ANOVA: p = 0.001). Intrahepatic tissue pO2 distribution after 6 hours of reperfusion more closely returned to preischemic configuration in the INT group than in the CNT group, indicating reduced microcirculatory disturbances after INT occlusion. Release of AST and LDH after 6 hours of reperfusion was significantly increased in both CNT and INT groups. Lower AST levels, however, were found after INT occlusion than after CNT occlusion (267.0 +/- 74.7 U/l and 603.3 +/- 132.4 U/l, respectively; p = 0.06). CONCLUSIONS: Intermittent hepatic vascular inflow occlusion during prolonged liver ischemia in pigs resulted in less microcirculatory and hepatocellular injury, compared to continuous occlusion. Intermittent clamping is preferable when prolonged periods of vascular inflow occlusion are applied during liver resections.  相似文献   
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25.

Background

Radical resection remains the only curative treatment for hilar cholangiocarcinoma (HCCA). Only a limited proportion of patients, however, are eligible for resection. The survival and prognostic factors of these patients are largely unknown. The aim of this study was to evaluate survival and prognostic factors in unresectable patients presenting with HCCA.

Methods

We performed a cohort study of the denominator of HCCA patients seen in a tertiary referral center between March 2003 and March 2009. Demographics, treatment, pathology results, and survival were analyzed.

Results

A total of 217 patients with suspected HCCA were identified. Ninety-five patients (40?%) underwent laparotomy, and in 57 (63?%) of these patients resection was performed. Overall median and 5-year survival of resected patients were 37?months and 43?%, respectively, as compared to 13?months and 7?% in unresectable patients. In unresectable patients, median survival was better in patients with locally advanced disease (16?months) as compared to patients with hepatic and extrahepatic metastases (5 and 3?months, p?Conclusion Of the patients presenting with HCCA in our center, 26?% proved resectable. The 7?% long-term survival rate of unresectable patients is remarkable and emphasizes the indolent growth of some of these tumors. Patients with metastases had a much worse prognosis with a median of 4?months.  相似文献   
26.

Purpose

This study was designed to determine the effectiveness of percutaneous balloon dilation and long-term drainage of postoperative benign biliary strictures.

Methods

Medical records of patients with postoperative benign biliary strictures, in whom percutaneous transhepatic biliary drainage (PTBD) and balloon dilation was performed between January 1999 and December 2011, were retrospectively reviewed. PTBD and balloon dilation (4–10 mm) were followed by placement of internal-external biliary drainage catheters (8.5–12 F). Patients were scheduled for elective tube changes, if necessary combined with repeated balloon dilation of the stenosis, at 3-week intervals up to a minimum of 3 months.

Results

Ninety-eight patients received a total of 134 treatments. The treatment was considered technically successful in 98.5 %. Drainage catheters were left in with a median duration of 14 weeks. Complications occurred in 11 patients. In 13 patients, percutaneous treatment was converted to surgical intervention. Of 85 patients in whom percutaneous treatment was completed, 11.8 % developed clinically relevant restenosis. Median follow-up was 35 months. Probability of patency at 1, 2, 5, and 10 years was 0.95, 0.92, 0.88, and 0.72, respectively. Overall, 76.5 % had successful management with PTBD. Restenosis and treatment failure occurred more often in patients who underwent multiple treatments. Treatments failed more often in patients with multiple strictures. All blood markers of liver function significantly decreased to normal values.

Conclusions

Percutaneous balloon dilation and long-term drainage demonstrate good short- and long-term effectiveness as treatment for postoperative benign biliary strictures with an acceptably low complication rate and therefore are indicated as treatment of choice.  相似文献   
27.
Incidence and management of pancreatic leakage after pancreatoduodenectomy   总被引:5,自引:0,他引:5  
BACKGROUND: Optimal management of severe pancreatic leakage after pancreatoduodenectomy can reduce morbidity and mortality. Completion pancreatectomy may be adequate but leads to endocrine insufficiency. This study evaluated an alternative management strategy for pancreatic leakage. METHODS: Outcome after disconnection of the jejunal limb, resection of the pancreatic body and preservation of a small pancreatic remnant, performed between 1997 and 2002, was compared with that after completion pancreatectomy performed between 1992 and 1996. RESULTS: Pancreatoduodenectomy was performed in 459 consecutive patients. Pancreatic leakage occurred in 41 patients (8.9 per cent); its incidence did not change over the study period. Non-surgical drainage procedures were performed in 14 patients, of whom one died, and surgical drainage in eight patients, of whom two died. Completion pancreatectomy was performed in nine patients with no deaths. A pancreatic remnant was preserved in ten patients, of whom three died. A remnant tail had to be resected in two patients and three patients still developed endocrine insufficiency ('brittle' diabetes). CONCLUSION: The incidence of pancreatic leakage did not change over the study interval. Preservation of a small pancreatic tail was associated with higher morbidity and mortality rates than those of completion pancreatectomy.  相似文献   
28.
CT criteria for venous invasion in patients with pancreatic head carcinoma   总被引:21,自引:0,他引:21  
The purpose of the study was to evaluate CT criteria for venous invasion in patients with potentially resectable carcinoma of the pancreatic head, with surgical and histopathological correlation. In 113 patients evaluated with spiral CT for suspected pancreatic head carcinoma, several CT criteria for venous invasion were scored prospectively for the portal vein (PV) and the superior mesenteric vein (SMV): length of tumour contact with PV/SMV (0 mm, < 5 mm, > 5 mm); circumferential involvement of the vein (0 degree, 0-90 degrees, 90-180 degrees, > 180 degrees); degree of stenosis; irregularity of the vessel margin; and tumour convexity towards vessel. 65 patients underwent surgery. Pancreatic head carcinoma was proven and pathology of the vascular margin was obtained in 50 of these patients. CT findings for single and combined criteria were correlated with pathology in these 50 patients, 30 of whom showed venous ingrowth. Invasion was found in all cases with SMV narrowing (n = 7), PV contour involvement > 90 degrees (n = 6), PV narrowing (n = 5) and PV wall irregularity (n = 3). The vascular ingrowth rate was 88% (15/17) for tumour concavity towards the PV or SMV. Poor predictors of ingrowth were length of tumour contact with PV > 5 mm (78% ingrowth, 14/18) and contour involvement of the SMV > 90 degrees (83% ingrowth, 10/12). Absence of vascular ingrowth could not be predicted in 100%. In conclusion, CT criteria can predict a high risk of invasion in potentially resectable tumours. Narrowing of the SMV and the PV seems the most reliable criterion, as well as circumferential involvement of the PV > 90 degrees. The best combination of criteria was tumour concavity with circumferential involvement > 90 degrees (sensitivity 60% and positive predictive value 90%).  相似文献   
29.
30.
Diagnostic and therapeutic strategies for acute biliary inflammation/infection (acute cholangitis and acute cholecystitis), according to severity grade, have not yet been established in the world. Therefore we formulated flowcharts for the management of acute biliary inflammation/infection in accordance with severity grade. For mild (grade I) acute cholangitis, medical treatment may be sufficient/appropriate. For moderate (grade II) acute cholangitis, early biliary drainage should be performed. For severe (grade III) acute cholangitis, appropriate organ support such as ventilatory/circulatory management is required. After hemodynamic stabilization is achieved, urgent endoscopic or percutaneous transhepatic biliary drainage should be performed. For patients with acute cholangitis of any grade of severity, treatment for the underlying etiology, including endoscopic, percutaneous, or surgical treatment should be performed after the patient's general condition has improved. For patients with mild (grade I) cholecystitis, early laparoscopic cholecystectomy is the preferred treatment. For patients with moderate (grade II) acute cholecystitis, early laparoscopic or open cholecystectomy is preferred. In patients with extensive local inflammation, elective cholecystectomy is recommended after initial management with percutaneous gallbladder drainage and/or cholecystostomy. For the patient with severe (grade III) acute cholecystitis, multiorgan support is a critical part of management. Biliary peritonitis due to perforation of the gallbladder is an indication for urgent cholecystectomy and/or drainage. Delayed elective cholecystectomy may be performed after initial treatment with gallbladder drainage and improvement of the patient's general medical condition.  相似文献   
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