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21.

Objectives

To assess the effectiveness of corticosteroids in the prophylaxis of postoperative atrial fibrillation (AF) in patients undergoing elective coronary artery bypass grafting or valvular heart surgery in terms of reducing its incidence and decreasing the length of hospital stay.

Methods

This prospective double blinded randomized study was conducted at Queen Alia Heart Institute (Amman, Jordan) from June 2014 to June 2015 on 340 patients who underwent their first on-pump elective coronary artery bypass grafting (CABG) alone or combined with valvular surgery. Inclusion criteria consisted of elective first time CABG or combined with valvular surgery, use of β-adrenergic blockade, and normal sinus rhythm. Exclusion criteria included a history of heart block, previous episodes of AF or flutter, uncontrolled diabetes mellitus, history of peptic ulcer disease, systemic bacterial or mycotic infection, permanent pacemaker, and any documented or suspected supraventricular or ventricular arrhythmias. Patients were randomized into two equal groups (n = 170 each), then each group was subdivided into patients who underwent CABG alone (n = 120), and patients underwent valvular heart surgery with or without CABG (n = 50). In the treatment group, patients were given 1 g of methylprednisolone before cardiopulmonary bypass then 100 mg of hydrocortisone every 8 hours for the first 3 days postoperatively. The primary endpoint was the overall occurrence of postoperative AF.

Results

AF developed in 21.1% (36 patients) in the treatment group in contrast to 38.2% (65 patients) in the control group (p < 0.05). In the subdivided groups (CABG only), approximately 20% (24 patients) developed AF in the treatment group in contrast to 35% (42 patients) in the control group (p < 0.05). In the other group, (CABG + VALVE) 24% (12 patients) developed AF compared with 46% (23 patients) in the control group (p < 0.05). The length of hospital stay was 6.02 ± 11.23 days in the treatment group while it was 5.98 ± 1.86 days in the control group, which was found to be statistically nonsignificant. No statistical significant difference in the rate of postoperative complications including mediastinitis as well superficial wound infections was observed between the two groups.

Conclusion

Prophylactic short-term use of steroids both intraoperatively and postoperatively proved to be safe and effective in reducing the incidence of postoperative AF in patients undergoing CABG alone or combined with valve surgery.  相似文献   
22.
OBJECTIVE: Some genome-wide scans and association studies for schizophrenia susceptibility genes have yielded significant positive findings, but there is disagreement between studies on their locations, and no mutation has yet been found in any gene. Since schizophrenia is a complex disorder, a study with sufficient power to detect a locus with a small or moderate gene effect is necessary. METHOD: In a genome-wide scan of 382 sibling pairs with a diagnosis of schizophrenia or schizoaffective disorder, 396 highly polymorphic markers spaced approximately 10 centimorgans apart throughout the genome were genotyped in all individuals. Multipoint nonparametric linkage analysis was performed to evaluate regions of the genome demonstrating increased allele sharing, as measured by a lod score. RESULTS: Two regions with multipoint maximum lod scores suggesting linkage were found. The highest lod scores occurred on chromosome 10p15-p13 (peak lod score of 3.60 at marker D10S189) and the centromeric region of chromosome 2 (peak lod score of 2.99 at marker D2S139). In addition, a maximum lod score of 2.00 was observed with marker D22S283 on chromosome 22q12, which showed evidence of an imprinting effect, whereby an excess sharing of maternal, but not paternal, alleles was present. No evidence of linkage was obtained at several locations identified in previous studies, including chromosomes 1q, 4p, 5p-q, 6p, 8p, 13q, 15p, and 18p. CONCLUSIONS: The findings of this large genome-wide scan emphasize the weakness and fragility of linkage reports on schizophrenia. No linkage appears to be consistently replicable across large studies. Thus, it has to be questioned whether the genetic contribution to this disorder is detectable by these strategies and the possibility raised that it may be epigenetic, i.e., related to gene expression rather than sequence variation. Nevertheless, the positive findings on chromosome 2, 10, and 22 should be pursued further.  相似文献   
23.
Internal fixation in proximal femoral osteotomies using traditional devices may be sub-optimal in children with neuromuscular disorders who have small or osteopenic bone. In this population, between 1988 and 2000, we performed 36 proximal femoral varus osteotomies in 28 patients. These were controlled by the AO external fixator. The average age at surgery was 7 years (range, 2-13 years). A mean varus correction of 34 degrees (range, 15-90 degrees) was obtained. Complications consisted of one superficial pin tract infection, one skin breakdown, and one non-union. Other than the non-union, all osteotomies were stable at the time of the fixator removal. The AO external fixator is an effective alternative in maintaining corrective proximal femoral osteotomies in children with fragile bones.  相似文献   
24.
The deleted in colorectal cancer (DCC) gene is a candidate tumor suppressor gene that may be associated with differentiation and proliferation of normal cells. Loss of heterozygosity (LOH) of 18q, where the gene is located, and absence of DCC protein expression have been associated with worse prognosis in certain subgroups of patients with colorectal adenocarcinoma. We studied the prognostic significance of loss-of-protein expression in 66 patients with resected gastric cancer with a high probability of relapse (T3, T4, N+). The DCC protein was detected with immunohistochemistry using an anti-DCC monoclonal antibody on paraffin-embedded sections. The DCC protein expression was present in 51 cases (77.3%) and absent in 15 cases (22.7%). Poorly differentiated and signet ring carcinomas had significantly lower expression than more differentiated tumors (p < 0.05) as did diffuse-type tumors compared to intestinal and mixed (p < 0.01). There was no correlation with proliferation rate, estimated immunohistochemically using an anti-proliferating cell nuclear antigen (PCNA) monoclonal antibody. Absence of DCC protein was an independent favorable prognostic factor (median survival 57 months vs. 18 months, p = 0.0176). The DCC protein expression was correlated with relapse site: all patients with distant metastases were positive for DCC staining, while one-third of patients with local/peritoneal relapse were negative (p < 0.01). In conclusion, DCC protein expression seems to be a significant prognostic factor in high-risk resected gastric cancer. Our results support previous data associating the DCC gene with differentiation and indicate that this gene may play a role in the metastatic potential of these tumors. These findings need to be confirmed by future larger studies.  相似文献   
25.
Human cytosolic beta-glycosidase is a small monomeric enzyme that is active under physiological conditions, which might be ideal for enzyme-prodrug therapy. We have previously reported the synthesis of a galactoside (DNR-GlA3) and a glucoside (DNR-GsA3) prodrug of daunorubicin. In the present study, we established that cellular uptake of DNR-GlA3 and DNR-GsA3 was low in contrast to that of daunorubicin. Recombinant human beta-glycosidase converted both prodrugs to daunorubicin as shown by liquid chromatography. The kinetics of the conversion of DNR-GlA3 and DNR-GsA3 by human beta-glycosidase, however, was unfavorable as the K(m) values were, respectively, 3- and 6-fold higher than those of another mammalian beta-glycosidase of bovine origin. The V(max) values were, respectively, 3.3 and 8.5nmol/hr/mg as compared to 158.3 and 147.8nmol/hr/mg of the bovine enzyme. Treatment of OVCAR-3 cells with human beta-glycosidase (0.5U/mL) and 0.5 microM DNR-GlA3 or DNR-GsA3 resulted in, respectively, 86 and 81% cell growth inhibition, while the prodrugs alone inhibited growth to only 19 and 1%. Treatment of cells with the bovine enzyme and the prodrugs inhibited cell growth more efficiently. We conclude that the endogenous intracellular beta-glycosidase is not available for extracellular prodrug activation. Thus, the incorporation of the enzyme in enzyme-prodrug therapy might be an elegant approach to achieve tumor-specific prodrug conversion. The efficiency of glycoside prodrug conversion might be improved by design of a prodrug that is more readily activated by human beta-glycosidase or by evolution of the enzyme into a mutant form that displays high activity towards these prodrugs.  相似文献   
26.
Pulp therapy in the primary dentition is an area undergoing continual changes. Treatment involves numerous methods and the use of a variety of dental materials. This article discusses various techniques and materials used in pulp therapy in the primary dentition. It includes a summary of the morphology, indications, contraindications, techniques for pulpotomies and pulpectomies, and contemporary treatment modalities used in the primary dentition.  相似文献   
27.
28.
Neonatal diabetes mellitus (DM) develops within the first six weeks of life with basic findings including dehydration, hyperglycaemia, and mild or no ketonemia/ketonuria. It can be either transient or permanent. Here, we report a case of a one-month-old infant with permanent neonatal diabetes, due to pancreatic hypoplasia, accompanied by diabetic ketoacidosis (DKA). The hyperglycaemia and ketoacidosis resolved by the 14(th) hour of treatment, consisting of IV insulin and rehydration. Subsequently, insulin treatment was continued with neutral protamine hagedorn (NPH) insulin. Breastfeeding was started and was continued at intervals of three hours. Following initiation of breastfeeding, the stools became watery, loose, yellow-green in color, and frequent (8-10 times a day). They contained no blood or mucus. Replacement of pancreatic enzymes resulted in decreased stool frequency. Neonatal DM due to pancreatic hypoplasia and associated with DKA may mimic sepsis and should be kept in mind in all newborns who present with fever, dehydration, and weight loss.  相似文献   
29.

Gastroenterology Research

Gastroenterology elsewhere  相似文献   
30.
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