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1.
OBJECTIVES: The increasing number of fixed-angle plate systems used to treat distal radius fractures carries with it the problem of determining the optimal fixation for unstable fractures. Our goal was to analyze the clinical and radiological outcomes of patients with displaced, unstable distal radius fractures treated with a palmar fixed-angle plate. DESIGN: Prospective protocol; multicenter clinical study; retrospective analysis. SETTING: Level 1 university trauma centers. PATIENTS: Over a mean 15-month period (range, 12 to 27 months), 141 consecutive patients were treated for an unstable dorsally displaced distal radius fracture of which 114 or 81% were followed for 1 year or longer. INTERVENTION: Open reduction and palmar internal fixation with a fixed-angle plate (2.4 mm LCP Distal Radius Plates; Synthes, Salzburg, Austria). Indication for surgical treatment was the inability to obtain or maintain fracture or articular alignment after initial closed reduction. MAIN OUTCOME MEASURES: In a follow-up period, which had to be longer than 12 months, objective and subjective functional results (active range of motion; strength; Disabilities of the Arm, Shoulder, and Hand (DASH) score; visual analog scale (VAS); Green and O'Brien Score) and radiographic assessment (palmar tilt, radial inclination, ulnar variance, fracture union) were assessed. Potentials for complications were given special attention. RESULTS: In the 114 patients followed for a minimum of 12 months, there were 21 men and 93 women with a mean age of 57 years (17 to 79 years). Fractures were classified according to the AO/ASIF classification system as type A2 (n = 39), A3 (n = 16), C1 (n = 24), C2 (n = 30), or C3 (n = 5). The modified Green and O'Brien Score revealed 31 excellent, 54 good, 23 fair, and 6 poor results. Active wrist motion averaged 54 degrees extension (82% as compared with the uninjured side) and 46 degrees flexion (72% as compared with the uninjured side). The average pronation was 81 degrees (95% as compared with the uninjured side), and the average supination was 82 degrees (95% as compared with the uninjured side). Mean grip strength at final follow-up was 70% of the uninjured side. Low residual pain values in the wrist were demonstrated: 81 patients (71%) were pain free, 17 patients (15%) had mild pain, 10 patients (9%) had moderate pain, and 6 patients (5%) had severe pain. The DASH score averaged 13 points (range, 0 to 39 points). Fracture union was achieved in all patients. A mean loss of palmar tilt of 3.4 degrees (range, 0 to 8 degrees), radial inclination of 0.4 degrees (range 0 to 2 degrees), and of the ulnar variance of 1.2 mm (range, 0 to 6 mm) was measured. The overall complication rate was 27% (31/114). The most frequent problems were flexor and extensor tendon irritation (57% of the total number of complications), including 2 ruptures of the flexor pollicis longus tendon, 2 ruptures of the extensor pollicis longus tendon, 4 cases of extensor tendon tenosynovitis, and 9 cases of flexor tendon tenosynovitis. Carpal tunnel syndrome was observed in 3 patients, and complex regional pain syndrome occurred in 5 patients. In 2 cases, loosening of a single screw was seen. Delayed fracture union occurred in 3 patients, and intraoperative intraarticular screw displacement was recognized in 1 patient. Neither clinical outcome nor complication rate were dependent on fracture type (intraarticular versus extraarticular). CONCLUSION: Fixation of unstable dorsally displaced distal radius fractures with a fixed angle plate provides sufficient stability with minimal loss of reduction. Nevertheless, very distal palmar plate position can interfere with the flexor tendon system, too long screws can penetrate the extensor compartments, and distal screws in comminuted fracture patterns can cut through the subchondral bone and penetrate into the radiocarpal joint. Mindful of these problems, we consider that the complex fracture pattern of an unstable distal radius fracture cannot be treated by a single plate system and approach.  相似文献
2.
This morphometric and experimental study was designed to assess the dimensions and axes of the subaxial cervical pedicles and to compare the accuracy of two different techniques for subaxial cervical pedicle screw (CPS) placement using newly designed aiming devices. Transpedicular fixation is increasingly used for stabilizing the subaxial cervical spine. Development of the demanding technique is based on morphometric studies of the pedicle anatomy. Several surgical techniques have been developed and evaluated with respect to their feasibility and accuracy. The study was carried out on six conserved human cadavers (average age 85 years). Axes and dimensions of the pedicles C3-C7 (60 pedicles) were measured using multislice computed tomography (CT) images prior to surgery. Two groups consisting of 3 specimens and 30 pedicles each were established according to the screw placement technique. For surgical technique 1 (ST1) a para-articular mini-laminotomy was performed. Guidance of the drill through the pedicle with a handheld aiming device attached onto the medial aspect of the pedicle inside the spinal canal. Screw hole preparation monitored by lateral fluoroscopy. In surgical technique 2 (ST2) a more complex aiming device was used for screw holes drilling. It consists of a frame with a fully adjustable radiolucent arm for carrying the instruments necessary for placing the screws. The arm was angled according to the cervical pedicle axis as determined by the preoperative CT scans. Drilling was monitored by lateral fluoroscopy. In either technique 3.5 mm screws made of carbon fiber polyetheretherketone (CF-PEEK) were inserted. The use of the CF-PEEK screws allowed for precise postoperative CT-assessment since this material does not cause artifacts. Screw placement was qualified from ideal to unacceptable into four grades: I = screw centered in pedicle; IIa = perforation of pedicle wall less than one-fourth of the screw diameter; IIb = perforation more than one-fourth of the screw diameter without contact to neurovascular structures; III = screw more than one-fourth outside the pedicle with contact to neurovascular structures. Fifty-six pedicle screws could be evaluated according to the same CT protocol that was used preoperatively. Accuracy of pedicle screw placement did not reveal significant differences between techniques 1 and 2. A tendency towards less severe misplacements (grade III) was seen in ST2 (15% in ST2 vs. 23% in ST1) as well as a higher rate of screw positions graded IIa (62% in ST2 vs. 43% in ST1). C4 and C5 were identified to be the most critical vertebral levels with three malpositioned screws each. Because of the variability of cervical pedicles preoperative CT evaluation with multiplanar reconstructions of the pedicle anatomy is essential for transpedicular screw placement in the cervical spine. Cadaver studies remain mandatory to develop safer and technically less demanding procedures. A similar study is projected to further develop the technique of CPS fixation with regard to safety and clinical practicability.  相似文献
3.
The authors present a retrospective clinical and radiological study addressing the outcome after posterior stabilisation of thoracolumbar fractures with intervertebral fusion via transpedicular bone grafting. The study included computed tomographic (CT) scan after implant removal for analysis of the intervertebral fusion and incorporation of the intervertebral bone graft and its influence on postoperative re-kyphosing. Twenty-nine patients with acute fractures of the thoracolumbar spine, treated between 1988 and 1995 at the Department of Trauma Surgery, Hannover Medical School, underwent posterior stabilisation and interbody fusion with transpedicular cancellous bone grafting. This study group was followed clinically and radiologically for a mean of 3.5 years. All patients underwent spiral CT scan with sagittal reconstruction after implant removal. Twenty-four type A, four type B, and one type C lesion were posteriorly stabilised and transpedicular intervertebral bone grafting was performed. The operative time averaged 2 h 50 min, the intraoperative fluoroscopy time 4 min 7 s, and the mean intraoperative blood loss was 376 ml. Four patients out of six with an incomplete neurologic lesion (Frankel/ASIA D) improved to Frankel/ASIA grade E. Two complications were observed: one delayed wound healing and one venous thrombosis with secondary pulmonary embolism. Compared to the preoperative status, our follow-up examinations demonstrated permanent social sequelae: the percentage of individuals able to do physical labor was reduced, whereas the proportion of unemployed or retired patients increased. The assessment of complaints and functional outcome with the Hannover Spine Score reflected a significant difference ( P<0.001) between the status before injury (96.6/100 points) and at follow-up (64.4/100 points). The radiographic follow-up revealed a mean loss of correction of 7.8 degrees ( P<0.005). CT scans after implant removal showed an interbody fusion and incorporation of the transpedicular bone graft in ten patients (34%). In another ten patients (34%), the CT scans demonstrated the interbody fusion at the anterior and posterior walls of the vertebral body via direct contact due to collapse of the disc space. In these patients, the bone graft was not incorporated and no central interbody fusion could be found. In nine patients (31%) neither interbody fusion nor incorporation of the transpedicular graft was achieved. A frequent and reliable intervertebral fusion could not be achieved with the described technique of transpedicular bone grafting. The ineffectiveness of the intervertebral graft was found to be a reason for postoperative re-kyphosing.  相似文献
4.
BACKGROUND: FOXP3+ regulatory T-cells (Treg) are important regulators of allo-reactivity and may therefore represent an important predictor for the risk of graft versus-host disease (GVHD) after allogeneic stem cell transplantation. METHODS: To determine the clinical significance of Treg-content in stem cell grafts, we analyzed 58 human leukocyte antigen (HLA)-identical sibling donors (34 patients received myeloablative and 24 patients reduced intense conditioning regimens) and correlated the Treg frequency with clinical outcome after stem cell transplantation (SCT). RESULTS: A mean value of 9.1 x 10(6) CD4+ FOXP3+ Treg per kg body weight (bw) of the recipient was transplanted (ranging from 0.7 to 33.7 x 10(6) Treg/kg bw). Graft content of Treg correlated with mononuclear cells and CD3+ T-cells. Patients receiving low numbers of Treg (Treg(low)) after myeloablative conditioning for SCT had a significantly increased cumulative incidence of 76% for acute GVHD when compared with 23% for individuals receiving high numbers of Treg (Treg(high)). This observation, however, was not made in patients after reduced intense conditioning-SCT. Notably, relapse rate was not significantly different between Treg(low) and Treg(high) patients in either patient group and overall survival was even increased in Treg(high) patients after myeloablative SCT. Finally, low Treg graft levels represent an independent prognostic factor in multivariate analysis for the appearance of acute GHVD. CONCLUSION: Donor-derived Treg might be of particular significance for the development of acute GVHD after myeloablative SCT using HLA-identical sibling donors.  相似文献
5.
The immunomodulatory enzyme indoleamine 2,3-dioxygenase (IDO) is activated by interferon-gamma (IFN-gamma) and via tryptophan depletion, suppresses adaptive T cell-mediated immunity in inflammation, host immune defense, and maternal tolerance. Its role in solid organ transplantation is still unclear. Therefore, we investigated the usefulness of IDO-mediated tryptophan catabolism in the evaluation of kidney allograft rejection. Blood, urine, and tissue samples were collected from 34 renal transplant patients without rejection and from nine patients with biopsy-confirmed episodes of acute rejection (n=12). Concentrations of kynurenine and tryptophan in serum and urine were analyzed by high-pressure liquid chromatography. Kynurenine to tryptophan ratio (kyn/trp) was calculated to estimate IDO activity. Immunostaining for IDO was performed on renal biopsies. Neopterin was assessed using radioimmunoassay. Kyn/trp and neopterin were detectable at low levels in serum of healthy volunteers and were increased in non-rejecting allograft recipients. Serum levels of kyn/trp were higher in recipients with rejection compared to non-rejectors as early as by day 1 post-surgery. Rejection episodes occurring within 13+/-5.9 days after transplantation were accompanied by elevated kyn/trp in serum (114+/-44.5 micromol/mmol, P=0.001) and urine (126+/-65.9 micromol/mmol, P=0.02) compared to levels during stable graft function. Kyn/trp correlated significantly with neopterin suggesting an IFN-gamma-induced increase in IDO activity. Immunostaining showed upregulation of IDO in rejection biopsies, localized in tubular-epithelial cells. Non-rejected grafts displayed no IDO expression. Acute rejection is associated with simultaneously increased serum and urinary kyn/trp in patients after kidney transplantation. Thus, IDO activity might offer a novel non-invasive means of immunomonitoring of renal allografts.  相似文献
6.
Ischemia and reperfusion (IR) are known to negatively affect early allograft function following solid organ transplantation. Lipocalin-2 (Lcn-2) has been described as a marker and potential positive modulator of acute inflammation during these processes. Using a heterotopic murine heart transplant model we previously found that IR resulted in a pronounced upregulation of Lcn-2 mRNA in the heart at 12 (22.7-fold increase) and 24 h (9.8-fold increase) of reperfusion. We now confirm this increase at the protein level and provide evidence for infiltrating polymorphonuclear cells as the primary source of Lcn-2 protein. Lcn-2 levels are increased 6.6-fold at 12 h, 11.4-fold at 24 h and 6.4 fold at 48 h after reperfusion. In Lcn-2(-/-) grafts the number of infiltrating granulocytes is reduced by 54% (p < 0.05) at 2 h, 79% (p < 0.01) at 12 h, 72% (p < 0.01) at 24 h and 52% (p < 0.01) at 48 h after reperfusion compared to Lcn-2(+/+) grafts, without any differences in cardiomyocyte apoptosis. These data suggest a function of Lcn-2 in the initiation of the inflammatory response. Moreover, an increase in Lcn-2 is not only restricted to the transplanted heart, but is also observed in the kidney, hinting at a possible involvement of Lcn-2 in the systemic response to IR.  相似文献
7.
Previous efforts to use adipocyte transplants for tissue augmentation have been limited by high and unpredictable resorption rates. Preadipocytes are precursor cells that are capable of replication and differentiation into mature adipocytes. Furthermore, they are more resilient to ischemia, making them a desirable transplant media. Utilizing fibrin glue as a transport vehicle and a prefabricated intramuscular capsule pouch as the recipient site, we have demonstrated the successful transplantation of cultured preadipocytes without the previously presented resorption sequelae. Histological analysis at 2 weeks has demonstrated establishment of vascular supply and the complete resorption of fibrin glue. Most importantly, using planimetric analysis, volume retention has been demonstrated in implanted areas up to 1 year following implantation. Finally, BrdU labeling has been utilized to demonstrate the lack of increased and uncontrolled replication rate, an index of potentially tumorigenic tissue. In conclusion, we have demonstrated a potentially new and safe source of tissue augmentation in the rat model.  相似文献
8.
Reliability of epigastric auscultation to detect gastric insufflation   总被引:3,自引:3,他引:1  
Background. We studied the reliability of epigastric auscultationto detect gastric insufflation in 30 anaesthetized, paralysedintubated patients. Methods. A 16FG gastric tube was positioned with the tip inthe mid-oesophagus with the proximal end attached to an injectionport with a one-way valve. Four observers participated in thestudy. Observers were paired and each pair studied 15 patients.Each patient underwent four test sequences in random order,two by each observer. Each test sequence comprised one observerinjecting different volumes of air (0.25 ml, 0.5 ml,1 ml, 2 ml, 3 ml, 4 ml, 5 ml, 10 ml,15 ml and 0 ml as a control) in random order whilstthe second blinded observer listened with a stethoscope overthe epigastrium. Each randomized volume was injected rapidlyat 5 s intervals for 1 min. The number of injectionsrequired to detect air entering the stomach was recorded. Thestomach was deflated between each test sequence. Results. To detect air entering the stomach with 95% confidence,11 injections were required for 0.25 ml; 7 for 0.5 ml;3 for 1 ml; 2 for 2 ml and 3 ml, and 1 for  相似文献
9.
Background: This study was performed to determine what consequences surgery for morbid obesity has on weight loss, problems in eating behavior, quality of life, physical appearance and mental state. Method: After a minimum follow-up of >8 months (median follow-up 21 months, range 8-48 months), a questionnaire concerning extent of, satisfaction with and consequences of weight loss was mailed to 250 morbidly obese patients after laparoscopic Swedish adjustable gastric banding (SAGB). In addition, the partner's opinion regarding the operation was evaluated as well as the consequences of weight loss for partnership and sexual relationship. Results: 160 patients (64%) completed and returned the questionnaire. Most patients (87%) were happy with the extent of weight loss. Weight loss, however, was connected with negative consequences for the body such as flabby skin (53%), abdominal skin overhang (47%) and pendulous breasts (42%). Patients who were satisfied with their postoperative physical appearance showed significantly less weight loss than did patients who were unhappy with their appearance (38 vs 54 kg). Most of the partners (91%) believed that the decision for SAGB was right. An improvement in partnership was reported by more than half of the partners (59%), and an improved sexual relationship by 45%. Conclusion: Laparoscopic SAGB is an effective surgical treatment for morbid obesity. However, the consequences of excess and rapid weight loss for physical appearance are negative in many cases. Well-directed information about the consequences of excess weight loss before SAGB and the possibilities and limits of plastic surgery must be given preoperatively to offset high and often unrealistic expectations.  相似文献
10.
The primary limitation of the laryngeal mask airway (LMA®)  相似文献
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