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51.
Objective: To report four cases of rice bodies (RBs) showing remarkable size variations and discuss their pathogenesis. Design and patients: Based on analysis of the clinical data, we speculate on the pathogenesis of RBs using immunohistochemical and ultrastructural methods. The patients comprised three men and one woman, three with RBs in the subacromial bursae and one in the wrist synovial sheath, aged 28 (woman), 44, 50 and 81 (wrist) years, respectively. Results: There were no particular differences in clinical data among the patients. T2-weighted MR imaging was very useful for diagnosis of the RBs, allowing their clear delineation from the bursal fluid. The RBs consisted of a layered protein- aceous substance with vague targetoid cut surfaces. Much fibrin and a lesser amount of collagen fibers were recognized together with various mononuclear cells, which were few in number and predominantly T cells. The bursae and synovial sheath had multiple fibrinoid spheroids at the luminal surface. Conclusion: Fibrinoid nodular deposits probably became detached, forming the nuclei of RBs and growing to a giant RB 65 mm in diameter. Received: 27 September 1999 Revision requested: 5 January 2000, 21 March 2000 Revision received: 21 March 2000, 14 April 2000 Accepted: 8 June 2000  相似文献   
52.
A 23-year-old woman with liver cirrhosis secondary to primary sclerosing cholangitis was referred to us for the treatment of recurrent bleeding from esophageal varices that had been refractory to endoscopic sclerotherapy. Her portal vein was occluded, associated with cavernous transformation. A transjugular intrahepatic portosystemic shunt (TIPS) was performed after a preprocedural three-dimensional computed tomographic angiography evaluation to determine feasibility. The portal vein system was recanalized and portal blood flow increased markedly after TIPS. Esophageal varices disappeared 3 weeks after TIPS. Re-bleeding and hepatic encephalopathy were absent for 3 years after the procedure. We conclude that with adequate preprocedural evaluation, TIPS can be performed safely even in patients with portal vein occlusion associated with cavernous transformation.  相似文献   
53.
Hepatolithiasis is more frequently seen in East Asian countries than in Western countries, and it is well known to represent a high-risk state for intrahepatic cholangiocarcinoma. Intrahepatic cholangiocarcinoma is an aggressive tumor that shows a dismal outcome even after resection. Cancer results from multistep carcinogenesis; however, the precise molecular mechanisms involved in the genetic alterations in cancer remain unknown. The accumulation of alterations in cancer-related genes leads to disruptions in cell-cycle regulation and also to continuous cell proliferation. The present review provides an overview of cancer-related genes in intrahepatic cholangiocarcinogenesis arising in hepatolithiasis. Further study of molecular mechanisms in hepatolithiasis-related intrahepatic cholangiocarcinoma, and the delineation of the influence of the genes involved should lead to our understanding of cholangiocarcinogenesis.  相似文献   
54.
Mucinous cystic neoplasms (MCN) of the pancreas are rare tumors that are almost exclusively located in the body or the tail of the pancreas. A 60-year-old woman with no history of pancreatic disease was referred to our hospital with a chief complaint of dull pain in the upper abdomen. Abdominal computed tomography showed a multilocular cystic mass of 7.0 cm in the head of the pancreas, and endoscopic retrograde cholangiopancreatography showed no communication between the cystic mass and the main pancreatic duct. A pancreatoduodenectomy was performed for the complete resection of the tumor, and an annular pancreas was discovered by accident. The pathological examination of the tumor led to a definitive diagnosis of MCN with ovarian-type stroma. To our knowledge this is the first documented case of MCN occurring in the head of the pancreas and associated with annular pancreas.  相似文献   
55.

Background

Saline-linked electric cautery (SLC) is introduced as an effective device to reduce blood loss in liver surgery. The aim of the current study was to evaluate the safety and efficacy of a 2-surgeon technique using SLC and the Cavitron Ultrasonic Surgical Aspirator (CUSA; Valleylab, Boulder, CO) in living donor hepatectomy.

Methods

Forty-three living donor right hepatectomy cases were enrolled in this study. The first 28 cases underwent liver transection with CUSA alone (CUSA group), while additional SLC was applied in the current 15 cases (2-surgeon technique, TS group).

Results

Blood loss was significantly reduced by the 2-surgeon technique (1,115.2 ± 652.9 g in CUSA group vs 732.3 ± 363.6 g in TS group, P < .05). In the TS group, there was no bile leakage from the cut surface. The early graft function and postoperative recipient survival were not significantly different between the groups.

Conclusions

According to our single-center experience, blood loss and donor complications in living donor hepatectomies were significantly reduced using a 2-surgeon technique using CUSA and SLC, while maintaining the graft viability.  相似文献   
56.
An 82-year-old woman presented with a 5-day history of right upper quadrant pain. A physical examination showed a palpable tender mass in the right upper quadrant with Murphy's sign. The contrast-enhanced multidetector computed tomography (MDCT) scan clearly showed the twisted pedicle of the cystic duct and gallbladder mesentery on the right side of the gallbladder, thus showing a “whirl sign,” and a definitive diagnosis of gallbladder torsion was made. The patient underwent a cholecystectomy, resulting in a favorable outcome. Therefore, the whirl sign on MDCT imaging can be a key to making a definitive diagnosis of gallbladder torsion.  相似文献   
57.

Purpose

No studies have used stress analysis with finite element analysis (FEA) to determine the causes of and mechanisms underlying rotator cuff tears. Therefore, we performed a biomechanical evaluation of the changes in stress distribution on the rotator cuff using three-dimensional (3-D) FEA.

Methods

The 3-D FEA model of shoulder joint allowed for abduction angles of 0°, 45° and 90° from the plane of the scapula and included the anatomical insertion points of the three major rotator cuff tendons and the middle fibres of the deltoid muscle. Stress distribution of the supraspinatus tendon on 3-D FEA was validated by a comparison with cadaveric and two-dimensional finite element model.

Results

The principal stress peaked in the region approximately 1 cm proximal to the insertion of the supraspinatus tendon. Furthermore, the stress on the joint side increased at the anterior edge of the supraspinatus tendon at abduction angles of 45° and 90°.

Conclusion

There are differences in stress changes between the joint side and bursal side of the supraspinatus tendon within the angles of abduction. The maximal tensile stress was observed on the articular side of the anterior edge of the supraspinatus tendon at 90° abduction. Our results indicate that the difference in tensile stress between the two layers results in delamination and causes partial-thickness tears.

Level of evidence

Decision analysis, Level II.  相似文献   
58.
Anterior mediastinal hemangiomas are very rare neoplasms in mediastinal tumors. A 58-year-old woman was revealed to have a mass measuring 4×3 cm in size in the anterior mediastinum with calcification on computed tomography. It was initially suspected to be a thymoma. We performed tumor extirpation in November 1998. The tumor was close to the thymus and slightly adhered to the superior vena cava, ascending aorta and right phrenic nerve, however, it did not invade any surrounding organs. Histopathologically, it was diagnosed to be a venous type hemangioma composed of vessels covered by smooth muscle and a cavernous type hemangioma composed of dilated vessels covered by one layer of endothelial cells.  相似文献   
59.
The effects of the dietary Ca and P ratio, independent of any vitamin D effects, on bone mineralization and turnover was examined in 60 VDRKO mice fed different Ca/P ratio diets. High dietary Ca/P ratio promoted bone mineralization and turnover with adequate intestinal Ca and P transports in VDRKO mice. INTRODUCTION: To clarify the effects of the dietary calcium (Ca) and phosphorus (P) ratio (Ca/P ratio) on bone mineralization and turnover in null-vitamin D signal condition, vitamin D receptor knockout (VDRKO) mice were given diets containing different Ca/P ratios. MATERIALS AND METHODS: Five groups of 4-week-old VDRKO mice, 10 animals each, were fed diets for 4 weeks. Group 1 was wild-type littermate mice, fed the diet containing 0.5% Ca and P (Ca/P = 1). Group 2 was the control and was fed a similar diet (Ca/P = 1). Groups 3, 4, 5, and 6 were fed the following diets: 0.5% Ca and 1.0% P (Ca/P = 0.5), 1.0% Ca and 1.0% P (Ca/P = 1), 1.0% Ca and 0.5% P (Ca/P = 2), and 0.5% Ca and 0.25% P (Ca/P = 2). RESULTS AND CONCLUSIONS: Compared with group 2, serum calcium and phosphorus levels in groups 4-6 significantly increased. Serum parathyroid hormone levels increased in group 3 and decreased in group 5. The amounts of intestinal calcium absorption decreased in groups 3 and 4. Phosphorus absorption increased in group 3 and decreased in groups 4-6. Bone mineral content (BMC) and bone mineral density (BMD) of the femur in group 3 significantly decreased and increased in group 5. In the primary spongiosa of the proximal tibia, the trabecular bone volume (BV/TV) and osteoid thickness (O.Th) in group 3 significantly increased, and decreased in group 6. In groups 5 and 6, the numbers of the trabecular osteoclasts increased. In groups 2 and 4, and the secondary spongiosa was identified in 5 of 10 mice. In group 3, there was no secondary spongiosa in either mouse. Osteoid maturation time (OMT) significantly decreased, and bone formation rate (BFR/BS) increased in groups 4-6. These data indicate that the dietary Ca/P ratio regulates bone mineralization and turnover by affecting the intestinal calcium and phosphorus transports in VDRKO mice. They may suggest the existence of Ca/P ratio-dependent, vitamin D-independent calcium and phosphorus transport system in the intestine.  相似文献   
60.
Background/Purpose  While lipiodolized transarterial chemoembolization (lip-TACE) is effective for treating unresectable hepatocellular carcinoma (HCC), its effect for treating recurrent HCC after curative liver resection needs to be clarified. Methods  Of 163 patients who had undergone curative liver resection between 1992 and December 2003, 65 patients (39.8%) had recurrent HCC in the liver without extrahepatic recurrence and were indicated for lip-TACE. The overall survival rate after lip-TACE was calculated, and its correlation with factors such as the histology of the primary HCC and background noncancerous tissue were analyzed. Results  The overall survival rates after lip-TACE after the detection of the first recurrent HCC were 82.6%, 44.5%, and 24.8% at 1, 3, and 5 years, respectively. The factors affecting patient survival after lip-TACE were microscopic portal venous involvement of HCC at liver resection, grade of inflammation in the noncancerous liver parenchyma, and recurrence within 1 year after the initial liver resection. Multivariate analysis showed that the period between the resection and first recurrence had the highest hazard ratio. Conclusions  Lip-TACE is a reasonable procedure for treating recurrent HCC in selected patients who are not eligible for hepatic re-resection. When HCC recurred within 1 year from the primary liver resection, the effect of lip-TACE on patient survival was limited.  相似文献   
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