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BACKGROUND: The large and variable size of the renal vein has prompted most surgeons to select linear stapling devices to secure the vein during laparoscopic donor nephrectomy. Although effective, these stapling devices have a potential for misfire. Use of the nonabsorbable polymer ligating (NPL) clip during laparoscopic donor nephrectomy provides increased graft vessel length compared with the stapling device, and the NPL clip has a locking mechanism which may increase security compared with standard titanium clips. The objective of this study was to evaluate the safety and efficacy of the NPL clip for control of the renal artery and vein during hand-assisted laparoscopic donor nephrectomy (HALDN). METHODS: A retrospective chart review of 50 consecutive HALDN patients was conducted where two parallel NPL clips were used to control both the renal artery and vein. Information collected included demographic data, operative and postoperative data, and complications. RESULTS: Mean donor age was 33.4 years and body mass index was 25.8 kg/m2. Mean operative time was 266.0 min, mean hospital stay was 3.2 days, and mean warm ischemia time was 123.3 seconds. There were no transfusions, open conversions, or complications related to use of the NPL clip. A US 16,300 dollars disposable cost savings was seen during this 1-year period alone. CONCLUSIONS: The NPL clip was 100% safe and effective in controlling the renal artery and vein during HALDN, allowed for additional vessel length, and resulted in a disposable cost savings of US 362 dollars per patient.  相似文献   
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PURPOSE: Venous involvement develops in 5% to 10% of patients with renal cell carcinoma and is generally considered a relative contraindication to laparoscopic radical nephrectomy. To our knowledge we report the initial clinical series of laparoscopic radical nephrectomy for renal cell carcinoma associated with level I renal vein thrombus. MATERIALS AND METHODS: At our 2 institutions 8 patients each underwent laparoscopic radical nephrectomy for level I microscopic renal vein thrombus (group 1) and level I gross thrombus (group 2). In all 8 group 2 patients the level I thrombus was preoperatively diagnosed by computerized tomography. Mean renal tumor size in groups 1 and 2 was 7.8 and 12.4 cm., respectively. After controlling the renal artery the renal vein was secured by firing an endoscopic gastrointestinal anastomosis stapler on its collapsed, uninvolved proximal part adjacent to the vena cava. Intraoperative, postoperative and pathological parameters were assessed in the 2 groups. RESULTS: In group 1 laparoscopic radical nephrectomy was technically successful in all 8 patients. Mean operative time was 3.1 hours, mean estimated blood loss was 382 cc and mean hospital stay was 1.9 days. In 1 patient each a soft tissue and a vascular margin was positive for cancer. At a mean follow up of 19.5 months (range 2 to 36) metastatic disease occurred in 3 cases (38%). In group 2 laparoscopic radical nephrectomy was technically successful in 7 cases with open conversion in 1. Mean operative time was 3.3 hours, mean estimated blood loss was 354 cc and mean hospital stay was 2.3 days. Surgical soft tissue and the renal vein vascular margin of the transected vein were negative for cancer in all 8 cases. At a mean followup of 9.4 months (range 5 to 16) pulmonary metastasis developed in 1 patient (13%). CONCLUSIONS: Although it is an advanced procedure, laparoscopic radical nephrectomy in patients with level I renal vein thrombus is feasible, safe and follows established oncological principles.  相似文献   
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Laparoscopic nephrectomy for benign and inflammatory conditions   总被引:2,自引:0,他引:2  
OBJECTIVES: To evaluate the outcomes of laparoscopic nephrectomy for benign renal conditions associated with dense perinephric inflammation, such as xanthogranulomatous pyelonephritis (XGPN), pyonephrosis, tuberculous pyelonephritis, and calculus pyelonephritis, and compare outcomes with a matched group of patients undergoing open nephrectomy for similar indications. An additional objective was to evaluate factors predictive of complications and open conversions. PATIENTS AND METHODS: We retrospectively analyzed data from 84 patients with benign inflammatory diseases who underwent laparoscopic nephrectomy and compared the data with data from 94 matched patients undergoing open nephrectomy. Both groups were compared with regard to operative time, blood loss, intraoperative and postoperative complications, analgesia requirement, blood transfusion, and hospital stay. Univariate analysis assessed the predictive value of factors such as kidney size, presence of hilar lymphadenopathy, perinephric and perihilar adhesion, laterality and body mass index on complications and risk of open conversion. RESULTS: Mean operative time was 170 +/- 59.8 and 148 +/- 42.5 minutes, blood loss was 156.2 +/- 6.8 and 154.6 +/- 68.8 mL, analgesia requirement was 165 +/- 71.2 and 284 +/- 81 g diclofenac sodium, and average hospital stay was 4.34 +/- 0.8 and 8.07 +/- 1.8 days in the laparoscopic and open groups, respectively. Abnormal renal hilum (71%) and perihilar adhesions (86%) were common findings in patients with XGPN, whereas abnormal hilum and hilar lymphadenopathy (55%) were commonly seen in those with tuberculosis. The renal hilum was relatively unaffected in patients with pyonephrosis and calculus pyelonephritis. Pleural entry was more common (P < 0.0001) in the open group, and visceral injury was more common in the laparoscopic group (P = 0.04). Blood transfusion was necessary in 7% and 11% of patients in the laparoscopic and open groups, respectively. Open conversion was required in 8 cases (autosomal dominant polycystic kidney disease-3, pyonephrosis, 2, XGPN and calculus pyelonephritis, 3). Intestinal obstruction that required laparotomy and adhesinolysis developed in one patient in the laparoscopic group. CONCLUSION: Laparoscopic nephrectomy can be performed safely in most patients with benign inflammatory conditions that require surgical extirpation. Proper patient selection and technical modifications may help reduce morbidity. One should keep a low threshold for laparoscopic-assisted open conversion whenever necessary.  相似文献   
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INTRODUCTION: Leiomyosarcoma of the large bowel mesentery is a rare entity and characteristically behaves in an aggressive fashion. Surgical resection is the mainstay of treatment and offers both symptomatic and therapeutic benefit. CASE: We describe the case of a 55-year-old woman who presented with weight loss, increasing abdominal girth and a large solid inhomogenous mass within the abdomen and pelvis demonstrated on a computed tomography (CT) scan. The patient underwent an exploratory laparotomy and extensive tumor debulking procedure with complete resection of her tumor. Final pathology revealed leiomyosarcoma of the large bowel mesentery. The patient has chosen not to receive adjuvant therapy. CONCLUSIONS: Leiomyosarcoma of the large bowel mesentery often presents as an advanced lesion making surgical resection a challenging and potentially morbid procedure. Although surgical resection may be faced with significant morbidity, maximum surgical effort with complete resection offers the best overall outcome for patients with this disease.  相似文献   
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In normal conditions, nitric oxide (NO) is oxidized to the anion nitrite, but in hypoxia, this nitrite may be reduced back to NO by the nitrite reductase action of deoxygenated hemoglobin, acidic disproportionation, or xanthine oxidoreductase (XOR). Herein, is investigated the effects of topical sodium nitrite administration in a rat model of renal ischemia/reperfusion (I/R) injury. Rats were subjected to 60 min of bilateral renal ischemia and 6 h of reperfusion in the absence or presence of sodium nitrite (30 nmol) administered topically 1 min before reperfusion. Serum creatinine, serum aspartate aminotransferase, creatinine clearance, fractional excretion of Na(+), and plasma nitrite/nitrate concentrations were measured. The nitrite-derived NO-generating capacity of renal tissue was determined under acidic and hypoxic conditions by ozone chemiluminescence in homogenates of kidneys that were subjected to sham, ischemia-only, and I/R conditions. Nitrite significantly attenuated renal dysfunction and injury, an effect that was abolished by previous treatment of rats with the NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazole-1-oxyl-3-oxide (2.5 mumol intravenously 5 min before ischemia and 50 nmol topically 6 min before reperfusion). Renal tissue homogenates produced significant amounts of NO from nitrite, an effect that was attenuated significantly by the xanthine oxidoreductase inhibitor allopurinol. Taken together, these findings demonstrate that topically administered sodium nitrite protects the rat kidney against I/R injury and dysfunction in vivo via the generation, in part, of xanthine oxidoreductase-catalyzed NO production. These observations suggest that nitrite therapy might prove beneficial in protecting kidney function and integrity during periods of I/R such as those encountered in renal transplantation.  相似文献   
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BACKGROUND AND PURPOSE: Despite a 10% to 15% failure rate, endopyelotomy remains the treatment of choice for most patients with ureteropelvic junction (UPJ) obstruction. We present a novel technique of percutaneous endopyeloplasty, wherein a precise, full-thickness approximation of a standard longitudinal endopyelotomy incision is performed in a horizontal Heineke-Mikulicz fashion through the conventional solitary percutaneous tract via a nephroscope. We assess the feasibility and efficacy of percutaneous endopyeloplasty in a chronic porcine bilateral UPJ obstruction model and compare outcome data with those#10; of conventional endopyelotomy and laparoscopic pyeloplasty. MATERIALS AND METHODS: Partial UPJ obstruction was created in 20 kidneys (11 pigs) by laparoscopic ligation of the upper ureter over a 5F ureteral catheter. After development of hydronephrosis over a period of 4 to 6 weeks, percutaneous endopyeloplasty (N = 10), conventional percutaneous endopyelotomy (N = 5), or laparoscopic pyeloplasty (N = 5) was performed. The essential steps of percutaneous endopyeloplasty include retrograde ureteral catheterization, standard percutaneous endopyelotomy incision, mobilization of the distal ureteral lip, horizontal suturing of the endopyelotomy incision through the nephroscope, and nephrostomy drainage and ureteral stenting. Suturing was performed using a modified 5-mm laparoscopic device (Sew Right 5 SR; LSI Solutions, Rochester, NY), which was passed through the nephroscope. RESULTS: Percutaneous endopyeloplasty was technically successful in all 10 kidneys with a mean total operative time of 81.4 minutes (range 51-117 minutes). The mean endopyeloplasty suturing time was 29.4 minutes (range 20-64 minutes). Three kidneys required two sutures, while seven kidneys required three sutures to complete the endopyeloplasty. The solitary complication was a lower-pole infundibular stenosis. Over a mean follow-up of 7.7 weeks, all renal units showed relief of obstruction, as evidenced by regression of hydronephrosis,#10; improvement in T(1/2) and glomerular filtration rate on renogram, and a low intrapelvic pressure on Whitaker test. At autopsy, the endopyeloplasty site showed a fine, well-healed transverse scar with no evidence of residual suture on the mucosal surface. The mean caliber of the UPJ following endopyeloplasty (13.8F +/- 2.2F) was significantly greater (P = 0.01) than that following endopyelotomy (7.5F +/- 1.9F). Intraoperative extravasation on completion of endopyeloplasty was absent (N = 6) or mild (N = 4) compared with that seen in all five kidneys following endopyelotomy. CONCLUSION: Percutaneous endopyeloplasty is feasible, simple, reproducible, and effective. Its advantages over conventional endopyelotomy include transrenal performance of a Fenger-plasty, wider caliber of the UPJ, absence of extravasation, and shorter duration of ureteral stenting.  相似文献   
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