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41.
42.
Antibody-mediated rejection is well established for renal allografts but remains controversial for lung allografts. Cardinal features of antibody-mediated rejection in renal allografts include antibodies to donor human leukocyte antigen (HLA) and evidence for antibody action, such as complement activation demonstrated by C4d deposition. We report a lung allograft recipient with circulating antibodies to donor HLA who failed treatment for acute cellular rejection but responded to therapy for humoral rejection. To address the second criteria for antibody-mediated rejection, we determined whether complement activation could be detected by measuring C4d in bronchoalveolar lavage fluid (BALF) by ELISA. Airway allergen challenge of asthmatics activates the complement pathway; therefore, we used BALF from asthmatics pre- and post-allergen challenge to measure C4d. These controls demonstrated that ELISA could detect increases in C4d after allergen challenge. BALF from the index patient had elevated C4d concomitant with graft dysfunction and anti-donor HLA in the absence of infection. Analysis of BALF from 25 additional lung allograft recipients showed that C4d concentrations >100 ng/mL were correlated with anti-HLA antibodies (p = 0.006), but were also observed with infection and in asyptomatic patients. The findings support the occurrence of anti-HLA-mediated lung allograft rejection and suggest that C4d measurement in BALF may be useful in diagnosis.  相似文献   
43.
BACKGROUND CONTEXT: Although plate fixation enhances the fusion rate in multilevel anterior cervical discectomy and fusion (ACDF), debate exists regarding the efficacy of nonplating to rigid plate fixation in one-level ACDF. PURPOSE: To determine the efficacy of nonplating to rigid plate fixation in regards to fusion rate and clinical outcome in patients undergoing one-level ACDF with autograft. STUDY DESIGN: A review of 69 consecutive patients who underwent one-level ACDF with autograft and with or without rigid anterior cervical plate fixation. PATIENT SAMPLE: Sixty-nine patients who underwent one-level ACDF (mean age, 45 years) were evaluated for radiographic evidence of fusion (mean, 14 months) and for clinical outcome. All patients received tricortical iliac crest autografts. Disc space distraction was 2 mm, the grafts were inserted with the cortical surface positioned anteriorly, and each graft was countersunk 2 mm from the anterior vertebral border. Thirty-eight patients underwent nonplated ACDF and 31 patients underwent plated ACDF. Eighteen Orion (Sofamor-Danek, Memphis, TN), eight Atlantis (Sofamor-Danek) and five PEAK polyaxial (Depuy-Acromed, Rayham, MA) anterior cervical plating systems were used. Rigid plate fixation was used in all patients with instrumentation. Postoperatively, hard collars were worn 6 to 8 weeks in nonplated patients and soft collars were worn for 3 to 4 weeks in plated patients. Twenty-four patients were smokers (54.2% nonplating; 45.8% plating) and work-related injuries entailed 23 patients (47.8% nonplating; 52.2% plating). OUTCOME MEASURES: Fusion was assessed based on last follow-up of lateral neutral, flexion and extension radiographs. Radiographs were evaluated blindly to assess fusion and instrumentation integrity between nonplated and plated patients. Clinical outcomes were assessed with the Cervical Spine Outcomes Questionnaire and also assessed on last follow-up as excellent, good, fair or poor based on Odom's criteria. METHODS: Fusion rate and postoperative clinical outcome were assessed in 69 patients who underwent one-level ACDF with autograft and with or without rigid anterior plate fixation. Additional risk factors were also analyzed. Statistical significance was established at p<.05. RESULTS: Sixty-six patients (95.7%) achieved a solid fusion (100% nonplated; 90.3% plated). Nonunions occurred in three patients (1 smoker; 2 nonsmokers) with Orion instrumentation. Slight screw penetration into the involved and uninvolved interbody spaces occurred in one patient who was a nonsmoker and did not achieve fusion. One superficial cervical wound infection was noted in a nonplated patient. No other intraoperative or postoperative complications were noted. No statistically significant difference was noted between nonplating to rigid plating upon fusion rate (p>.05). All nonunions occurred at the C5-C6 level. Mean estimated intraoperative blood loss was significantly greater in plated patients (p=.043). Revision surgery involved 9.7% of the plated patients, whereas none of the nonplated patients required reoperation. Postoperative clinical outcome was assessed in all patients (mean, 21 months). Excellent results were noted in 18.8%, good results in 72.5% and fair results in 8.7% of the patients. Nonunion patients reported satisfactory clinical outcome. No statistical significance was noted between clinical outcome of fused and nonfused patients, the presence of a work-related injury and the use of plating (p>.05). Demographics and history of smoking were not factors influencing fusion or clinical outcome in this series (p>.05). The effect on fusion by various plate types could not be discerned from this study. CONCLUSION: A 100% and 90.3% fusion rate was obtained for one-level nonplated and plated ACDF procedures with autograft, respectively. The effects of smoking or level of fusion could not be discerned from these one-level cases. Excellent and good clinical outcome results were obtained for 91.3%. Nonplating or rigid plate fixation for ACDF in properly selected patients to treat radiculopathy with or without myelopathy has a high fusion rate and yields a satisfactory clinical outcome. Although controversy exists as to the efficacy of rigid plate fixation in one-level ACDF, solid bone fusion can be adequately obtained without plate fixation and instrumentation-related complications can be avoided. In line with the literature, plate fixation should be reserved for patients unwilling or unable to wear a hard orthosis postoperatively for an extended period of time or for those patients who seek a quicker return to normal activities. Proper patient selection, meticulous operative technique and postoperative care is essential to promote optimal graft-host incorporation.  相似文献   
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INTRODUCTION: Surgical morbidity and mortality rates are high in patients with Cushing's syndrome. Nevertheless, simultaneous bilateral laparoscopic adrenalectomy (LA) is feasible in these patients with less morbidity and good long-term results. BACKGROUND AND RESULTS: Consecutive 22 patients who underwent LA for Cushing's syndrome between 2003 and 2010 in our institute were retrospectively studied. Ninteen patients underwent bilateral simultaneous and three underwent unilateral LA. Seven patients had Cushing's syndrome after failed pituitary surgery and five each had ectopic adrenocorticotrophic hormone dependent syndrome and bilateral macronodular hyperplasia respectively. LA was bilaterally done by lateral transabdominal adrenalectomy in 15 patients and retroperitoneal endoscopic adrenalectomy in 4 on the right side. Mean operative time for simultaneous bilateral cases was 199.45±72.43 minutes with mean blood loss of 72.72±48.6 mL. Patients were fit for discharge by the fifth postoperative day from the surgical aspect. Surgical complication rate was 26% that included wound infections in two, port site hernia, pleural effusion, and atelectasis in one each. One patient died of sepsis (5% mortality). Satisfactory metabolic control was achieved in all observable patients in the long term although Addisonian crisis and Nelson syndrome were seen in 26% and 15% respectively. CONCLUSION: LA has all advantages of minimal access surgery in patients with Cushing's syndrome who are immunocompromised and at high risk of delayed wound healing and infections. Magnification decreases the risk of retained adrenal remnants. Despite advances in minimal access surgery, perioperative morbidity continues to be significant for the procedure.  相似文献   
46.
BackgroundRheumatoid arthritis is a chronic autoimmune disorder that commonly affects the metatarsophalangeal (MTP) joints. Conventional surgical treatment involves joint-sacrificing surgery to relieve pain and correct deformity.ObjectivesWe retrospectively reviewed 49 patients with rheumatoid forefoot deformities who underwent 66 joint preserving procedures with Scarf osteotomy of the first metatarsal and Weil's shortening osteotomy of the lesser metatarsals.MethodThere were 5 males and 44 females with mean age 56.1 years and mean follow-up 51 months. All patients were evaluated clinically and radiologically with hallux valgus angle (HVA) and inter-metatarsal angle (IMA).ResultsMean AOFAS score improved from 39.8 preoperatively to 88.7 at final follow-up. Subjectively patients reported their outcome as excellent in 49 feet (74%), good in 9 feet, fair in 7 feet and poor in 1 foot. Five feet had residual stiffness and 11 residual pain. Mean HVA and IMA decreased from 32° to 14° and from 15° to 11° respectively.ConclusionIn intermediate to severe stages of the disease, joint preserving surgery by Scarf osteotomy of the first MTP joint and Weil osteotomy of the lesser metatarsals may be performed as an alternative to joint-sacrificing procedures and should be considered as a complement to the various surgical treatments of the rheumatoid forefoot.  相似文献   
47.
Ten percent of all fractures lead to problems with healing. Smoking is said to be a cause. There are 13.5 million smokers in the U.K. Healing of tibial fractures, for instance, requires two more months in smokers. Nicotine, carbon monoxide and hydrogen cyanide are most often seen as the offenders, among the 4000 chemicals found in cigarettes. Many studies plead for the negative effect of smoking in general, yet there is uncertainty as to the precise role of nicotine. The authors recommend that patients should attempt smoking cessation therapy before elective orthopaedic treatment.  相似文献   
48.
Obesity is an epidemic in the United States and is associated with an increased risk of musculoskeletal problems. Rotational injuries of the ankle with a Weber C fibula fracture have a greater risk of syndesmosis disruption and instability. The goal of the present study was to explore the association between obesity and ankle fractures. Using a retrospective review, the radiographs of 280 patients with an ankle fracture were reviewed and classified using the Weber classification, which was then associated with the body mass index, gender, age, diabetes, tobacco use, and osteoporosis. Patients with a body mass index of 30 kg/m2 or greater (odds ratio 1.78), men (odds ratio 1.74), and age 25 years or younger (odds ratio 3.97) had greater odds of having a Weber C ankle fracture (compared with Weber A and B) and Weber C and B (compared with Weber A). Diabetes mellitus, osteoporosis/osteopenia, and current tobacco use were not significantly associated with the severity of the ankle fracture. The results from the present study suggest that obesity presents a greater risk of sustaining a more proximal distal fibula fracture.  相似文献   
49.
Athletic activity after total joint replacement   总被引:2,自引:0,他引:2  
Nicholls MA  Selby JB  Hartford JM 《Orthopedics》2002,25(11):1283-1287
Total hip and knee replacement surgery is a successful treatment for the arthritic hip and knee ensuring proven pain relief and return of function. Younger, more active patients who have greater expectations and higher demands are receiving hip and knee replacements. With current surgical techniques and implant designs, athletic participation should be limited to low impact, low demand, and low duration activity. Future advancesin bearing surfaces may allow for higher demand activities.  相似文献   
50.
The patient's own palm is used as a template in assessing small patchy burns and is traditionally believed to be 1% of body surface area. This does alter with the patient's age, sex and BMI and there have been suggestions that it can also differ between ethnic groups. We undertook this study to see if there were any differences in the hand surface area between Caucasians, Orientals and Asians. It was done by tracing the hand outline and calculating the surface area. The study showed that there was no significant difference between the three ethnic groups in terms of hand surface area.  相似文献   
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