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121.
The purpose of this phase III clinical trial was to compare two different extracellular contrast agents, 1.0 M gadobutrol and 0.5 M gadopentate dimeglumine, for magnetic resonance imaging (MRI) in patients with known or suspected focal renal lesions. Using a multicenter, single-blind, interindividual, randomized study design, both contrast agents were compared in a total of 471 patients regarding their diagnostic accuracy, sensitivity, and specificity to correctly classify focal lesions of the kidney. To test for noninferiority the diagnostic accuracy rates for both contrast agents were compared with CT results based on a blinded reading. The average diagnostic accuracy across the three blinded readers (‘average reader’) was 83.7% for gadobutrol and 87.3% for gadopentate dimeglumine. The increase in accuracy from precontrast to combined precontrast and postcontrast MRI was 8.0% for gadobutrol and 6.9% for gadopentate dimeglumine. Sensitivity of the average reader was 85.2% for gadobutrol and 88.7% for gadopentate dimeglumine. Specificity of the average reader was 82.1% for gadobutrol and 86.1% for gadopentate dimeglumine. In conclusion, this study documents evidence for the noninferiority of a single i.v. bolus injection of 1.0 M gadobutrol compared with 0.5 M gadopentate dimeglumine in the diagnostic assessment of renal lesions with CE-MRI.
Bernd TombachEmail:
  相似文献   
122.
Patellektomie nach Trauma—beeinflusst der Zeitpunkt das Ergebnis?   总被引:1,自引:0,他引:1  
Müller EJ  Wick M  Muhr G 《Der Unfallchirurg》2003,106(12):1016-1019

Aim of the study

Is there a correlation between the timing of patellectomy after trauma in crush injuries and the clinical outcome?

Methods

Retrospective analysis of 21 patients who had undergone patellectomy after trauma.

Results

In 12 patients (57.1%) a primary patellectomy was performed within 4 weeks after the fracture; in the remaining 9 (42.9%) patients the procedure was performed after an average of 21 months (range 2–72). Nineteen patients could be followed up after 9.3 years (range 3–18). In 10 of these, patellectomy had been performed primarily. The HSS Knee Score was 68.4 points (range 39–83) on average for all patients. For patients with a primary patellectomy the score was 71 points (range 54–83), while for patients in whom the patellectomy was performed secondarily the score was 63.8 points (range 39–77). The evaluated ROM was 113.6° for all patients; in the primary group ROM was 122.5° (range 65–145°), and in the secondary group it was 103° (range 85–145°). The difference was not statistically significant for either parameter.

Conclusion

Primary reconstruction of the patella is recommended in multifragmentary fractures; if the outcome is poor, however, patellectomy should be considered early.
  相似文献   
123.
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   
124.
Diagnosis of non-palpable breast cancer: a review   总被引:3,自引:0,他引:3  
The literature on several methods of diagnosing non-palpable breast carcinoma has been reviewed. Skin projection and dye are methods not frequently used. Several aspects of FNA biopsy/cytology, ultrasound-directed methods, frozen section and MRI localization procedures are highlighted and comparisons are made. Much attention is being payed to needle localization breast biopsy and stereotactic core needle breast biopsy. The management of patients with mammographic abnormalities is shifting from needle localization to breast biopsy stereotactic core needle biopsy. Items of comparison between the two mentioned methods are accuracy, indications, complications and costs. The role of the ABBI system in the management of breast cancer has not yet been defined. A cooperative effort between the mammographer, surgeon and pathologist is critical to a successful image-guided breast biopsy programme.  相似文献   
125.
Between March 2012 and August 2013, 591 quality forms were filled out for abdominal organs in the Netherlands. In 133 cases (23%), there was a discrepancy between the evaluation from the procuring and transplanting surgeons. Injuries were seen in 148 (25%) organs of which 12 (2%) led to discarding of the organ: one of 133 (0.8%) livers, five of 38 (13%) pancreata and six of 420 (1.4%) kidneys (P < 0.001). Higher donor BMI was a risk factor for procurement‐related injury in all organs (OR: 1.06, P = 0.011) and donor after cardiac death (DCD) donation in liver procurement (OR: 2.31, P = 0.034). DCD donation is also associated with more pancreata being discarded due to injury (OR: 10.333, P = 0.046). A higher procurement volume in a centre was associated with less injury in pancreata (OR = −0.95, P = 0.013) and kidneys (OR = −0.91, P = 0.012). The quality form system efficiently monitors the quality of organ procurement. Although there is a relatively high rate of organ injury, the discard rate is low and it does not significantly affect 1‐year graft survival for any organ. We identified higher BMI as a risk factor for injury in abdominal organs and DCD as a risk factor in livers. A higher procurement volume is associated with fewer injuries.  相似文献   
126.
127.
Nowadays in cases of nonunions of the femoral neck, the surgeon is tempted to perform prosthetic replacement of the hip, more so if there is also evidence of avascular necrosis of the head of femur. This provides rapid pain relief and allows early mobilization. However, long-term results of hip arthroplasties, especially in younger people and in the presence of osteopenia, are not always as expected; and a less radical approach is worth considering. The intertrochanteric valgization osteotomy, described by Pauwels, is an excellent alternative for healthy patients up to 65 years of age with a nonunion of the femoral neck. A union rate of 80-90% of the nonunion is described by most authors. Leg length inequallity, rotational and angular deformities can be corrected at the same time. During the period 1973-1995, we performed valgization osteotomy according to Pauwels in 66 patients of, 18-72 years old (mean 49.5 years). 24 (37%) of our patients died 4 months to 24 years (mean: 9.5 years) after the operation. Union of the femoral neck was achieved in 58 (88%) of the 66 patients; union of the osteotomy in 65 patients (99%). A good or excellent result was achieved in 62% (23 uneventful and 13 with healed, necrosis/arthrosis without need for further treatment) of our patients. However, the method has its limits. We feel if there is too little bone stock inside the femoral head, a valgization osteotomy does not give good result. The radiographic signs of avascular necrosis in patients over 30 years of age is considered a contraindication for an osteotomy. However our results show that it is worthwhile trying to save the joint of young patients even in case of a segmental collapse. In the race between revascularization and collapse, often revascularization is the winner. We deliberately give nature its chance and don''t rely on the result of bleeding from drill holes in the head, nuclear scans and other methods to estimate vascularity. A secondary total hip replacement if necessary because of avascular necrosis or osteoarthritis is considerably postponed; and better milieu for hip replacement can be achieved by the development of sclerotic bone in the subchondral areas of the acetabulum and femoral head. Between 65 and 80 years of age, a total hip replacement is probably the best option for fit patients. We treat fresh femoral neck fractures with a hemiarthroplasty in patients over the biological age of 80 years. Logically the same choice will be made for patients with a nonunion. During the period 1973-1995 we performed hemiarthroplasty (n = 34) in patient with low general condition. Their mean age was 79 years. The average survival in these patients was less than three years and that explains probably the low late complication rate: in this group. Total hip replacement was performed in 37 younger patients with a mean age of 69 years. They were not considered for a valgization osteotomy because of age being over 70 years, severe osteoporosis or a total collapse of the femoral head. In this group, we observed one aseptic cup revision and two extractions of the prosthesis because of a deep infection.  相似文献   
128.
Background The outcome and quality of surgical treatment in gastric cancer are closely associated with specific postoperative morbidity and mortality, in addition to an oncosurgically adequate resection status. In this context, a preventive concept of decreasing the insufficiency rate of esophageal anastomosis may have a great impact.Method Over a time period of 12 months (from 1 January 2002 to 31 December 2002), 1,199 patients (from 80 East German hospitals) with gastric carcinoma, carcinoma of the esophagogastral junction, or gastrointestinal stroma tumor (GIST) were enrolled in this prospective multicenter observational study with the aim of evaluating their early postoperative outcome. By means of a logistic regression analysis, independent variables, which alter significantly the healing of esophagojejunal anastomosis, were determined; in addition, their clinical impact on preventive management to lower the insufficiency rate of esophageal anastomosis was investigated.Results In 1,139 patients, histological investigation revealed gastric carcinoma. Out of these patients, 1,031 subjects underwent surgical intervention (90.5%) and 891 individuals underwent resection (86.4%). In 813 patients, radical resection (subtotal resection and gastrectomy) was executed (78.9%), whereas in 726 cases, R0 resection was achieved (81.5%). Gastrectomy was the preferred procedure in 649 patients, resulting in a gastrectomy rate of 62.9% relating to all patients who underwent operation (curative and palliative intention, 80.3% and 19.7%, respectively). The insufficiency rate of esophagojejunal anastomosis was 5.7% (37/649). Neither the comparison between the various procedures for the reconstruction of the esophagojejunal passage and anastomosing techniques after gastrectomy nor that between gastrectomies with curative and palliative intention revealed any significant difference. Dysphagia and gastric outlet syndrome due to a stenosis were determined as independent variables by a logistic regression analysis of all preoperative and intraoperative variables. In all patients with gastric carcinoma, both parameters were recorded in 9.9% (113/1,139) and 6.7% (76/1,139), respectively.Conclusion Dysphagia and gastric stenosis, which significantly influence the healing of esophagojejunal anastomosis after gastrectomy, are considered characteristics of an advanced tumor growth and a pretherapeutic lack of an adequate nutrition. This emphasizes the necessity of an early diagnosis of gastric cancer in order to lower perioperative morbidity. In addition, dysphagia is commonly associated with an obstruction of the upper gastrointestinal tract, which can lead to nutritional deficits, and thus deserves specific care during preventive management.  相似文献   
129.
BACKGROUND: We aimed to test whether stenotic microvasculopathy affects the more beneficial course in female cardiac transplant recipients. METHODS: We studied 873 patients (35/151 premenopausal women aged < or =40 years) who underwent primary heart transplantation. In 7750 biopsies harvested within the first posttransplant year endothelial disease and stenotic microvasculopathy were evaluated by light microscopy (Hematoxylin and Eosin). Kaplan-Meier and Cox regression analyses were performed for major cardiac events (MACE; lethal myocardial infarction, sudden cardiac death, graft failure, and cardiac retransplantation). RESULTS: Stenotic microvasculopathy was found equally in men (38%) and women (39%). Allografts from premenopausal female-to-male transplants more frequently developed endothelial disease (78% vs. 65%; P=0.021) and stenotic microvasculopathy (46% vs. 28%, P=0.024). Beyond the first 5 posttransplant years women presented MACE less often than men, independently of donor gender and stenotic microvasculopathy (P=0.0001). Multivariate regression analysis found women to be at lower risk for MACE (Relative Risk [RR] 0.38; 95% Confidence Interval [CI] 0.17-0.81), whereas stenotic microvasculopathy (RR 2.15; 95% CI 1.42-3.26) and treated diabetes (RR 1.65; 95% CI 1.08-2.52) indicated a higher risk for MACE. CONCLUSIONS: Stenotic microvasculopathy has prognostic impact on survival of male and female cardiac recipients; however, it does not affect the more beneficial course of women in the long-term follow-up.  相似文献   
130.
Endobronchial ultrasound (EBUS) and autofluorescence bronchoscopy (AFB) are the two technologies to have the largest impact on diagnostic bronchoscopy in the last forty years. The AFB utilizes inherent tissue properties to identify preinvasive lesions of the central airways. The EBUS can accurately define airway invasion versus compression from tumors, guide transbronchial needle aspiration of hilar and mediastinal lymph nodes, and predict, based on ultrasound morphology, whether peripheral nodules are benign or malignant. It is also extremely useful for determining the proximal and distal extent of tumors in and around the airway, and aid in surgical planning. This article will review the principles and clinical applications of these two technologies.  相似文献   
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