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731.
The constancy of the hydrogen consuming flora of the human colon was studied in 15 healthy subjects via two measurements obtained 18 to 36 months apart. Hydrogen disappearance rate and the major products of H2-consuming bacteria, methane and sulfide, were measured during incubation of fecal homogenates with excess hydrogen and sulfate. In 11/15, the hydrogen consumption rate and the predominant hydrogen-consuming pathway (methanogenesis, sulfate reduction, or neither) remained constant. However, major shifts in these pathways were observed in four subjects, with two losing and two gaining the ability to produce methane. Methanogenesis was associated with the highest hydrogen consumption rate. This study demonstrates that clinically unrecognizable, major alterations of the colonic flora occur in healthy subjects. Understanding of the factors responsible for these alterations might allow for therapeutic manipulation of the colonic flora.Supported in part by the Department of Veterans Affairs and NIDDKD RO1 DK 13309-25.  相似文献   
732.
Recombinant human erythropoietin (rHuEPO) stimulates erythropoietic bone marrow cells and increases erythrocyte production. This prospective study was designed to evaluate the effects of rHuEPO on regeneration of erythropoiesis after allogeneic or autologous bone marrow transplantation (BMT). Seventeen centers participated in this randomized, double-blind, placebo-controlled multicenter trial. The randomization was performed centrally for each center and stratified according to allogeneic or autologous BMT and major ABO-blood group incompatibility. One hundred and six patients received rHuEPO after allogeneic BMT and 109 patients received placebo. After autologous BMT, 57 patients were treated with rHuEPO and 57 with placebo. Patients received either 150 IU/kg/day C127 mouse-cell-derived rHuEPO or placebo as continuous intravenous infusion. Therapy started after bone marrow infusion and lasted until independence from erythrocyte transfusions for 7 consecutive days with stable hemoglobin levels > or = 9 g/100 mL or until day 41. After allogeneic BMT, the reticulocyte counts were significantly higher with rHuEPO from day 21 to day 42 after BMT. The median time (95% confidence intervals) to erythrocyte transfusion independence was 19 days (range, 16.3 to 21.6) with rHuEPO and 27 days (range, 22.3 to > 42) with placebo (P < .003). The mean (+/- SD) numbers of erythrocyte transfusions until day 20 after BMT were 6.6 +/- 4.8 with rHuEPO and 6.0 +/- 3.8 with placebo. However, from day 21 to day 41, the rHuEPO-treated patients received 1.4 +/- 2.5 (median, 0) transfusions and the control group received 2.7 +/- 4.0 (median, 2) transfusions (P = .004). In the follow-up period from day 42 up to day 100, 2.4 +/- 5.6 transfusions were required with rHuEPO and 4.5 +/- 9.6 were required with placebo (P = .075). A multivariate analysis (ANOVA) showed that acute graft-versus-host disease (GVHD), major ABO-blood group incompatibility, age greater than 35 years, and hemorrhage significantly increased the number of transfusions. However, after day 20, rHuEPO significantly reduced the number of erythrocyte transfusions in these patient groups, as well as reducing incompatibility in the major ABO-blood group. For the whole study period, rHuEPO reduced the transfusion requirements in GVHD III and IV from 18.4 +/- 8.6 to 8.5 +/- 6.8 U (P = .05). After autologous BMT, there was no difference in the time to independence from erythrocyte transfusions and in the regeneration of reticulocytes. Marrow purging strongly increased the requirement for transfusions as well as the time to transfusion independence.  相似文献   
733.
BACKGROUND : Bone marrow transplant (BMT) patients, although immunosuppressed, are at risk for the development of red cell (RBC) and HLA antibodies, and they often are given filtered blood in an effort to prevent the latter complication. This study attempts to determine the rate of formation and the specificity of both RBC and HLA alloantibodies in this patient population. STUDY DESIGN AND METHODS : BMT patients (148 received autologous marrow; 45 received allogeneic marrow) from an 18-month period, including patients with leukemia (57 patients), lymphoma (54), breast cancer (68), myeloma (8), myelodysplastic syndrome (5), and aplastic anemia (1), were studied to determine the rate of alloantibody formation to RBC and HLA antigens. A total of 2,410 RBC antibody screens were performed. The patients received 3,921 packed RBCs and 5,915 single-donor platelet units; all were irradiated and administered via white cell-reduction filters. RESULTS : Seven (3.6%) of 193 patients had RBC antibodies upon hospital admission. Four (2.1%) of 193 developed RBC antibodies during the course of BMT: 3 patients had one RBC antibody and 1 patient had two RBC antibodies. RBC antibodies included anti-E (n = 2), anti-M (n = 1), anti-Jkb (n = 1), and anti-Lu14 (n = 1). Thus, 98 percent of patients (189/193) did not develop new (182/186) or additional (7/7) RBC antibodies during BMT. BMT patients were also screened weekly for HLA antibody formation (60-cell panel). Upon admission, 170 (85%) patients were negative. Of these, 8 (4.7%) developed persistent HLA antibodies (mean panel-reactive antibody score, 33 +/? 29%) and 9 (5.3%) were variably positive. Thus, in our setting and population, RBC antibody formation was 0.1 percent per unit transfused, and the HLA alloimmunization rate was 5 to 10 percent. CONCLUSION : As RBC antibody screens are done every Monday, Wednesday, and Friday on this BMT service and as RBC antibody formation is low in these patients, screening for unexpected antibodies might be possible on a more infrequent basis. Also, the rate of HLA alloimmunization in this population receiving filtered blood components is low.  相似文献   
734.
Binding of urokinase-type plasminogen activator (uPA) to its glycosylphosphatidylinositol-anchored receptor (uPAR) initiates signal transduction, adhesion, and migration in certain cell types. To determine whether some of these activities may be mediated by associations between the uPA/uPAR complex and other cell surface proteins, we studied the binding of complexes composed of recombinant, soluble uPA receptor (suPAR) and single chain uPA (scuPA) to a cell line (LM-TK- fibroblasts) that does not express glycosylphosphatidylinositol (GPI)-anchored proteins to eliminate potential competition by endogenous uPA receptors. scuPA induced the binding of suPAR to LM-TK- cells. Binding of labeled suPAR/scuPA was inhibited by unlabeled complex, but not by scuPA or suPAR added separately, indicating cellular binding sites had been formed that are not present in either component. Binding of the complex was inhibited by low molecular weight uPA (LMW-uPA) indicating exposure of an epitope found normally in the isolated B chain of two chain uPA (tcuPA), but hidden in soluble scuPA. Binding of LMW-uPA was independent of its catalytic site and was associated with retention of its enzymatic activity. Additional cell binding epitopes were generated within suPAR itself by the aminoterminal fragment of scuPA, which itself does not bind to LM-TK- cells. When scuPA bound to suPAR, a binding site for alpha 2-macroglobulin receptor/LDL receptor-related protein (alpha 2 MR/LRP) was lost, while binding sites for cell-associated vitronectin and thrombospondin were induced. In accord with this, the internalization and degradation of cell-associated tcuPA and tcuPA-PAI- 1 complexes proceeded less efficiently in the presence of suPAR. Further, little degradation of suPAR was detected, suggesting that cell- bound complex dissociated during the initial stages of endocytosis. Thus, the interaction of scuPA with its receptor causes multiple functional changes within the complex including the dis-appearance of an epitope in scuPA involved in its clearance from the cell surface and the generation of novel epitopes that promote its binding to proteins involved in cell adhesion and signal transduction.  相似文献   
735.
Oral Diseases (2011) 17 , 258–264 Objective: To analyse and compare the expression of Palate, Lung, and Nasal Epithelium Clone (PLUNC) proteins in salivary glands from patients with and without AIDS (control group) using autopsy material. Methods: We analysed the expression of PLUNCs using immunohistochemistry in parotid (n = 45), submandibular (n = 47) and sublingual gland (n = 37) samples of AIDS patients [30 with normal histology, 21 with mycobacteriosis, 14 with cytomegalovirus (CMV) infection, 30 with chronic non‐specific sialadenitis, and 30 HIV‐negative controls. In situ hybridization (ISH) for SPLUNC 2 in the HIV‐negative group was performed. Results: SPLUNC 1 expression was detected in the mucous acini of submandibular and sublingual glands, and SPLUNC 2 were seen in the serous cells. LPLUNC 1 expression was only positive in the salivary ducts. There was a higher expression of SPLUNC 2 in AIDS patients with CMV infection and mycobacteriosis when compared with all other groups. The intensity of staining for SPLUNC 2 was greater around the lesions than the peripheral ones. ISH for SPLUNC 2 showed perinuclear positivity in the serous cells in all HIV‐negative cases. Conclusions: SPLUNC 1 and LPLUNC 1 proteins were similarly expressed in the salivary glands of AIDS patients and non‐HIV patients. CMV infection and mycobacteriosis increase SPLUNC 2 expression in serous cells in the salivary gland of AIDS patients.  相似文献   
736.
Background:  To photoelastically examine load transfer by unilateral distal extension removable partial dentures with supporting and retentive components made of the lower stiffness polyacetal resins.
Methods:  A mandibular photoelastic model, with edentulous space distal to the right second premolar and missing the left first molar, was constructed to determine the load transmission characteristics of a unilateral distal extension base removable partial denture. Individual simulants were used for tooth structure, periodontal ligament, and alveolar bone. Three designs were fabricated: a major connector and clasps made from polyacetal resin, a metal framework as the major connector with polyacetal resin clasp and denture base, and a traditional metal framework I-bar removable partial denture. Simulated posterior bilateral and unilateral occlusal loads were applied to the removable partial dentures.
Results:  Under bilateral and left side unilateral loading, the highest stress was observed adjacent to the left side posterior teeth with the polyacetal removable partial denture. The lowest stress was seen with the traditional metal framework. Unilateral loads on the right edentulous region produced similar distributed stress under the denture base with all three designs but a somewhat higher intensity with the polyacetal framework.
Conclusions:  The polyacetal resin removable partial denture concentrated the highest stresses to the abutment and the bone. The traditional metal framework I-bar removable partial denture most equitably distributed force. The hybrid design that combined a metal framework and polyacetal clasp and denture base may be a viable alternative when aesthetics are of primary concern.  相似文献   
737.
The clinical effectiveness and scar quality of the randomized controlled trial comparing enzyme alginogel with silver sulfadiazine (SSD) for treatment of partial thickness burns were previously reported. Enzyme alginogel did not lead to faster wound healing (primary outcome) or less scar formation. In the current study, the health‐related quality of life (HRQoL), costs, and cost‐effectiveness of enzyme alginogel compared with SSD in the treatment of partial thickness burns were studied. HRQoL was evaluated using the Burn Specific Health Scale‐Brief (BSHS‐B) and the EQ‐5D‐5L questionnaire 1 week before discharge and at 3, 6, and 12 months postburn. Costs were studied from a societal perspective (health care and nonhealth‐care costs) for a follow‐up period of 1 year. A cost‐effectiveness analysis was performed using cost‐effectiveness acceptability curves and comparing differences in societal costs and Quality Adjusted Life Years (QALYs) at 1 year postburn. Forty‐one patients were analyzed in the enzyme alginogel group and 48 patients in the SSD group. None of the domains of BSHS‐B showed a statistically significant difference between the treatment groups. Also, no statistically significant difference in QALYs was found between enzyme alginogel and SSD (difference ?0.03; 95% confidence interval [CI], ?0.09 to 0.03; P = .30). From both the health care and the societal perspective, the difference in costs between enzyme alginogel and SSD was not statistically significant: the difference in health‐care costs was €3210 (95% CI, €‐1247 to €7667; P = .47) and in societal costs was €3377 (95% CI €‐6229 to €12 982; P = .49). The nonsignificant differences in costs and quality‐adjusted life‐years in favor of SSD resulted in a low probability (<25%) that enzyme alginogel is cost‐effective compared to SSD. In conclusion, there were no significant differences in quality of life between both treatment groups. Enzyme alginogel is unlikely to be cost‐effective compared with SSD in the treatment of partial thickness burns.  相似文献   
738.

Background:

Time from injury to fixation of femoral neck fractures has been postulated as a vital determinant for rate of complications; however, no prospective study is available in the English literature. Delay, unfortunately, is inevitable in developing countries. The aim of the present study is to retrospectively review the outcome after delayed fixation of displaced type II and III femoral neck fractures in children.

Materials and Methods:

Using a standard assessment chart, we retrospectively reviewed medical records of all pediatric patients having femoral neck fractures presenting to our institution from June 1999 to May 2006. Inclusion criteria were children between 5 and 15 years of age sustaining displaced Delbet type II and III femoral neck fractures having a complete follow-up of at least 2 years. Patients with known metabolic disease, poliomyelitis or cerebral palsy, were excluded from the study. After application of inclusion and exclusion criteria, 22 patients having 22 fractures (13 type II and 9 type III) were studied. Surgery could be performed after a mean delay of 11.22 days (ranging from 2 to 21 days). Closed reduction was achieved in 14 cases and 8 cases required open reduction through anterolateral approach.

Result:

Osteonecrosis was noted in eight patients (36.37%) who included two of nine patients (22.22%) operated in the first week, three of eight patients (37.51%) operated in the second week, and three of five patients (60%) operated in the third week of injury. Nonunion was seen in four (18.18%) cases, and two of them were associated with failure of implants. One was treated by valgus osteotomy and the other by Meyer''s procedure. Fractures united in both children but the latter developed avascular necrosis. Functional results, as assessed using Ratliff''s criteria, were good in 14 (63.63%), fair in 2 (9%), and poor in 6 (27.27%) patients.

Conclusion:

Delay in fixation, type of fracture, and ability to achieve and maintain reduction are factors primarily responsible for the outcome. We also found that delay after the first week further adversely affects the outcome.  相似文献   
739.

Aim-Background

Infected pancreatic necrosis (IPN) develops in approximately one third of patients with necrotizing pancreatitis (NP). In the past, open necrosectomy (ON) was the standard treatment for this condition, but it carried significant morbidity and mortality. Currently, minimally invasive procedures (MIPs) have been established for the management of IPN, decreasing the risk of complications compared with ON.

Methods

A prospective study was made of patients with IPN treated by a MIP for necrosectomy via a percutaneous drainage catheter, followed by video-assisted retroperitoneal debridement (VARD).

Results

Between 2013 and 2016, 3 consecutive patients, with a mean age of 58 years, underwent a MIP for the management of IPN. All 3 patients had left lateral retroperitoneal pockets of necrosis, and the first-line procedure consisted of placement of a pigtail catheter. The drain tract was subsequently used to carry out VARD. None of the patients presented major postoperative complications or required re-intervention.

Conclusion

The management of IPN has shifted away from ON, which was associated with high morbidity, towards less invasive techniques. MIPs should be used initially as the surgical treatment of choice in most cases. When this is not feasible, or when the MIP is not successful, ON should be implemented.
  相似文献   
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