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This study investigates the syntactic abilities of ten individuals with Williams syndrome (WS) (mean chronological age: 8;9 years; mean mental age: 4;8 years) and Down's syndrome (DS) (mean chronological age: 8;7 years; mean mental age: 4;6 years), matched individually on chronological age, mental age and performance IQ. The syntactic components investigated include the comprehension of passives and the production, comprehension and repetition of wh‐questions. Performance is compared to ten younger typically developing (TD) controls matched individually to both experimental groups on mental age (mean chronological age: 4;4 years; mean mental age: 5;0 years). Participants were given a standardized measure of grammatical ability and non‐standardized tasks exploring the comprehension of active and passive sentences, and the production, comprehension and repetition of a range of wh‐question types: wh‐subject, wh‐object, which NP‐subject and which NP‐object. Participants with WS and DS performed similarly on the standardized measure of grammatical ability, as well as on the experimental tasks that tapped comprehension of passives, and production and comprehension of wh‐questions. Participants with DS performed significantly more poorly than both the WS cohort and TD controls on the repetition of wh‐questions. Both the WS and DS cohorts performed significantly more poorly on most of the syntactic tasks compared to the younger TD controls. Individuals with WS and DS experienced significant difficulties in tasks measuring aspects of syntactic ability and performed more poorly than mental age‐matched TD controls. Implications of these findings, with regards to the debates around language “intactness” in WS, as well as the similarities and differences in language abilities in WS and DS, dependent on age and developmental stages studied, are explored.  相似文献   
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PURPOSE: To determine whether ras-activated cascades lead to activation of ets-1 expression in sequential histological stages of oral oncogenesis in an experimental animal model. METHODS: Thirty-seven Syrian golden hamsters were divided into three experimental groups (A, B, C) and one control group. The hamsters' buccal pouches in experimental groups were treated with 0.5% 9, 10-dimethyl-1, 2-benzanthracene (DMBA) for 14 weeks and were excised at 10, 14, 19 weeks, respectively. The biopsies were classified pathologically (normal mucosa, hyperkeratosis, hyperplasia, dysplasia, early invasion, well and moderately differentiated carcinoma) and studied immunohistochemically. The two-tailed Student's t test was performed for each animal group and for each histological category. RESULTS: The ets-1 expression increased in early stages of oral tumor formation and invasion. The expression of N-ras gradually decreased during oral oncogenesis, as previously observed with H-ras. CONCLUSIONS: Neither N-ras nor H-ras affects ets-1 expression in contrast to other types of cancer in which N-ras and ets-1 are implicated in the same signalling pathway. Therefore, the existing pathway implicating these proteins might be somehow altered in oral cancer. It seems that ets-1 is a good prognostic marker for invasiveness and progression of oral cancer.  相似文献   
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The present study was performed in order to investigate the possible association of the -418 G/C polymorphism in the tissue inhibitor of metalloproteinase-2 (TIMP-2) gene, which affects its expression, with the risk of developing oral cancer. PCR-based restriction analysis was performed in DNA samples from 158 patients with oral squamous cell carcinoma (OSCC) and 168 healthy controls of equivalent sex, age and ethnicity (Greeks and Germans). Statistical analyses were performed with Fisher's exact test and the calculation of odds ratios with a 95% confidence interval (CI). The frequency of the low C allele expression was ten times greater in the patients than the controls (31% vs 2.7%, respectively; P<0.001). The C/C and G/C genotypes were associated with an increased risk of developing OSCC (P<0.001, OR=40.88, 95% CI=2.24-744.40, and P<0.001, OR=21.31, 95%=9.82-46.21, respectively). The same pattern of significant differences with the controls was also observed in the subgroups of patients in regard to the initial or advanced stages of oral cancer, family history of any type of cancer or thrombosis, and smoking habits or alcohol abuse. These findings are consistent with the reduced levels of TIMP-2 in the presence of the low expression C allele, which are insufficient to inhibit the matrix metalloproteinase-driven degradation of the extracellular matrix (leading to cancer invasion) and mitogen-driven neoangiogenesis (leading to tumor growth and metastasis). In conclusion, the studied TIMP-2 polymorphism is strongly associated with an increased risk of OSCC in Europeans carrying the low C allele expression. These results indicate that this polymorphism could serve as a genetic marker for the susceptibility of cancer in the oral cavity.  相似文献   
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Background

In addition to its role in the endogenous control of erythropoiesis, recombinant human erythropoietin (rh-EPO) has been shown to exert tissue protective properties in various experimental models. However, its role in the cardiac arrest (CA) setting has not yet been adequately investigated.

Aim

The aim of this study is to examine the effect of rh-EPO in a pig model of ventricular fibrillation (VF)-induced CA.

Methods

Ventricular fibrillation was electrically induced in 20 piglets and maintained untreated for 8 minutes before attempting resuscitation. Animals were randomized to receive rh-EPO (5000 IU/kg, erythropoietin [EPO] group, n = 10) immediately before the initiation of chest compressions or to receive 0.9% Sodium chloride solution instead (control group, n = 10).

Results

Compared with the control, the EPO group had higher rates of return of spontaneous circulation (ROSC) (100% vs 60%, P = .011) and higher 48-hour survival (100% vs 40%, P = .001). Diastolic aortic pressure and coronary perfusion pressure during cardiopulmonary resuscitation were significantly higher in the EPO group compared with the control group. Erythropoietin-treated animals required fewer number of shocks in comparison with animals that received normal saline (P = .04). Furthermore, the neurologic alertness score was higher in the EPO group compared with that of the control group at 24 (P = .004) and 48 hours (P = .021).

Conclusion

Administration of rh-EPO in a pig model of VF-induced CA just before reperfusion facilitates ROSC and improves survival rates as well as hemodynamic variables.  相似文献   
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Optimism is a key variable for adjustment in aversive conditions. The purpose of this study was to examine whether optimism is predicted by two stress‐related variables which represent information about self and the environment (i.e. illness‐related stress and self‐efficacy), in a sample of breast cancer survivors. Ninety‐two women who had undergone a mastectomy participated in the study (minimum time elapsed since diagnosis = 3 years). Most participants (51 per cent) reported that at least one of four illness‐related concerns had been quite or very stressful in the past 6 months. Analyses showed that illness‐related stress exerted influence on optimism through coping, whereas self‐efficacy exerted influence both directly and through coping. Stress was predicted by two medical variables (time since diagnosis and time since mastectomy). These findings confirmed our hypothesis that knowledge about personal abilities, as well as about environment difficulties can predict the way a person evaluates future outcomes. This study has significant implications for clinical practice with patients. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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BACKGROUND: Increased expression of fibroblast growth factors and their receptors (FGFRs) has recently been described in oral squamous cell carcinoma. In addition, we have previously described a molecular basis for an association between oral cancer and diabetes. The expression of FGFR-2 and FGFR-3 investigated in an experimental model of chemically induced carcinogenesis in normal and diabetic (type I) rats. MATERIALS AND METHODS: Tissue sections ranging from normal mucosa to moderately-differentiated oral squamous cell carcinoma were studied using monoclonal antibodies against FGFR-2 and FGFR-3 proteins. RESULTS: A similar pattern of elevated FGFR-2 and FGFR-3 expression was observed in the initial stages of oncogenesis for both diabetic and non-diabetic animals. In the last stages of oral oncogenesis, the expression of both proteins remained relatively stable. CONCLUSION: It seems that diabetes does not affect the FGFR-2 and FGFR-3 pattern of expression throughout the various stages of oral oncogenesis.  相似文献   
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