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71.
BACKGROUND: Androgenetic alopecia (AGA) has received scant attention, despite it being a common entity that may result in significant psychosocial morbidity. There are some patients who do not fit into any of the proposed types. Moreover, there have been no published studies of pattern and prevalence of AGA in males in an Indian context. Hence, the present study was an attempt to classify AGA in males with the aim of producing a simple, effective and easily reproducible classification. METHODS: In total, 150 male patients were clinically diagnosed as AGA. After obtaining informed consent from all patients, a detailed history/examination was carried out, including a hair pull test, a trichogram investigation and a biopsy. Classification of AGA was subsequently attempted across Norwood guidelines. RESULTS: A gradual shift in the type of AGA from the earlier types (II and III) to more severe types (VI) with increasing age was significant. Twenty-seven patients did not fit into specific patterns according to Hamilton and Norwood classifications. In addition, type 'a' variant was recorded in 20% of patients, clearly indicating limitations of the existing classifications. CONCLUSIONS: It was possible to classify 80% of the AGA, with II (28%) and III (15%) being the most common types of AGA. Twenty-seven patients (18%) could not be classified as a significant finding. There was considerable overlap in types IV, V and VI in the Norwood classification with the 'a' variants further confusing the picture.  相似文献   
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Purpose Hindlimb ischemia and reperfusion leads to lung injury in various animal models. We investigated the effectiveness of FK506, an immunosuppressive agent, which also modulates neutrophilic infiltration, in preventing lung injury after hindlimb ischemia and reperfusion in a rat model.Methods Twenty-seven male Sprague-Dawley rats were randomized to received FK506 at doses of 0.3mg/kg, 0.5mg/kg, or 1mg/kg body weight per day, or normal saline injections, as pretreatment, and there was also a sham group. On the 4th day, the animals were subjected to 2h of ischemia induced by a tourniquet, followed by reperfusion of the extremities for 2h. Lung tissue assays were performed for the lipid peroxidation product malondialdehyde (MDA) and total glutathione (GSH). Lung tissues were also examined histopathologically under light and electron microscopy.Results The MDA levels in the study groups were significantly lower than those in the control group (P < 0.05), but the total GSH levels did not differ significantly among the groups. Histopathologically, there were no significant differences among the groups given different doses of FK506, but there was a significant difference between the control group and all the treatment groups.Conclusion FK506 ameliorates the lung injury associated with ischemia and reperfusion of the lower limbs, and might have an inhibitory effect on the neutrophils that cause remote organ damage.  相似文献   
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Long-term follow-up after the mini-maze procedure   总被引:4,自引:0,他引:4  
BACKGROUND: Atrial fibrillation (AF) is associated with significant morbidity and mortality. The standard to treat AF surgically is the Cox maze III procedure but owing to its complexity it is not performed on a regular basis. Meanwhile several maze variants have been developed but their long-term results are still not well known. METHODS: From November 1995 until May 2002 a mini-maze procedure was performed upon 77 patients aged 64 +/- 8.7 years with chronic symptomatic AF. Electrophysiological evaluation, magnetic resonance imaging, echocardiography and electrocardiographic evaluations were performed after 3 and 12 months. After a mean follow-up of 50 +/- 2.6 months a standard questionnaire was sent to all patients. RESULTS: Early and late mortality was 1.2% and 9.3% respectively. Actuarial survival was 91%, 90%, and 87% after 1, 3, and 5 years respectively. Left bundle branch block was an independent risk factor for late death (p = 0.02). Patients who were in sinus rhythm at follow-up had significantly better survival rate as compared with the patients still in AF. Seventy-one percent of patients were in sinus rhythm or paced by an atrial pacemaker. Predictors for restoration of sinus rhythm were absence of preoperative mitral insufficiency (p = 0.03) and larger left atrium (p = 0.04). The presence of preoperative tricuspid insufficiency (p = 0.03) and larger right atrium (p = 0.017) were predictors for postoperative pacemaker implantation. CONCLUSIONS: The mini-maze procedure can be carried out with satisfactory early and long-term results regarding mortality and restoration of sinus rhythm. Prophylactic implantation of biventricular pacemakers in patients with left bundle branch block may decrease late mortality. Every effort should be done to cure AF as it affects long-term survival.  相似文献   
75.
BACKGROUND: Technetium 99m ( 99m Tc)-methoxyisobutylisonitrile (MIBI) single photon emission computed tomography (SPECT) is frequently used in the evaluation of patients with hyperparathyroidism. Calcium channel blockers (CACBs) may affect 99m Tc-MIBI uptake by parathyroid cells. This study examines the effect of CACB therapy on the sensitivity of 99m Tc-MIBI SPECT localization for hyperparathyroidism. METHODS: Two hundred fifty-three operated patients with hyperparathyroidism were retrospectively reviewed. The potential effect of CACB therapy on 99m Tc-MIBI scan sensitivity was examined by using logistic regression analysis. Possible confounding factors were considered. RESULTS: Among 235 patients, those with multiple endocrine neoplasia, type I (MEN-I), MEN-IIA, 4-gland hyperplasia, secondary hyperparathyroidism, and tertiary hyperparathyroidism exhibited no difference associated with CACB use. Of the remaining 198 patients with primary hyperparathyroidism, 7/30 (23%) with negative 99m Tc-MIBI SPECT scans compared to 24/168 (14%) with positive scans used CACBs. After correcting for age, gender and gland weight, the odds ratio (OR) for a negative study in patients taking CACBs was 2.88 (95% CI, 1.03-8.10; P = .045). Atherosclerosis, hypertension, diabetes mellitus, preoperative calcium and parathyroid hormone levels, and thyroid hormone use were not confounding factors. CONCLUSIONS: CACB therapy reduces the sensitivity of 99m Tc-MIBI parathyroid SPECT in patients with primary hyperparathyroidism. Further studies are required to determine the potential reversibility of this effect with termination of CACB therapy.  相似文献   
76.
BACKGROUND: Endotoxin, with its potential to enhance type 1 immunity, is a significant player in the hygiene hypothesis. The combined effects of the genetic variants of various molecules in the endotoxin response pathway on asthma related phenotypes are largely unknown. OBJECTIVE: To investigate the effects of the genetic variants of CD14 and TLR4 genes on asthma phenotypes in a large number of asthmatic children. METHODS: 613 asthmatic children were genotyped at the CD14-C159T, TLR4-A896G and TLR4-C1196T loci. IgE, eosinophil numbers and FEV1 were compared in 327 children who were not on any controller medications and were symptom free. Multivariate logistic regression was used to determine the factors associated with total IgE. RESULTS: Among children with atopic asthma, total IgE levels were significantly different among the three genotypes in the co-dominant model [CC: 435 kU/l (interquartile range: 146-820); CT: 361 (140-710); TT 204 (98-435), P = 0.035]. TT genotype was significantly and independently associated with lower IgE levels (OR: 0.5 95%; CI = 0.28-0.90, P = 0.021). Both TLR4-A896G and TLR4-C1196T polymorphisms were more frequent in the mild asthma group with atopy (P = 0.032, 0.018, respectively). The combined effects of the genetic variants in CD14 and TLR4 genes did not improve the observed associations. CONCLUSION: Our study demonstrates that the CD14-C159T promoter variant influences total IgE levels and also indicates that the T allele has a more profound effect on total IgE in children with atopic asthma. Polymorphisms in the TLR4 gene may be associated with milder forms of disease in atopic asthmatics in the population studied.  相似文献   
77.
This study was designed to investigate the effects of iron supplementation on the parameters of oxidative stress in the skeletal muscle tissue of hyperthyroidism induced rats. Hyperthyroidism was found to cause an increase in thiobarbituric acid-reactive substances (TBARS) and copper zinc superoxide dismutase (Cu, Zn SOD) activity, but decreases in the glutathione-peroxidase (GSH Px) activity and glutathione (GSH). Iron supplementation caused an increase in TBARS and a decrease in GSH. Iron supplementation in hyperthyroid rats attenuated the hyperthyroid state, but lowered the plasma ferritin level, which is considered an indicator of thyroid hormone action. Iron supplementation caused no additional increase in the TBARS in hyperthyroid rats, ameliorated the decrease in GSH content and abolished the induction of Cu, Zn SOD. Our findings suggested no increase, but a decrease, in the risk of oxidative stress in iron supplemented hyperthyroid rats. Whether supplementation of iron would have similar effects in humans should be further investigated in clinical studies.  相似文献   
78.
The distribution of three integrin subunits, alpha3, alpha5 and alpha(v), in immature and mature human oocytes has been examined using immunofluorescence and confocal microscopy. The results demonstrate that both alpha5 and alpha(v) are present at the germinal vesicle stage, while alpha3 was only detected in oocytes after germinal vesicle breakdown, in metaphase I and II stage oocytes. The cortical concentration of integrin subunits alpha3 and alpha5 is consistent with their localization in the oolemma. In contrast, the homogeneous distribution of alpha(v) throughout the oocyte suggests the existence of cytoplasmic reservoirs of this protein in the oocyte.   相似文献   
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