首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   167篇
  免费   9篇
  国内免费   1篇
儿科学   3篇
妇产科学   1篇
基础医学   24篇
口腔科学   16篇
临床医学   20篇
内科学   24篇
皮肤病学   27篇
神经病学   10篇
特种医学   2篇
外科学   9篇
综合类   1篇
预防医学   21篇
眼科学   1篇
药学   14篇
中国医学   3篇
肿瘤学   1篇
  2024年   1篇
  2023年   1篇
  2022年   5篇
  2021年   9篇
  2020年   5篇
  2019年   2篇
  2018年   6篇
  2017年   8篇
  2016年   3篇
  2015年   9篇
  2014年   9篇
  2013年   13篇
  2012年   14篇
  2011年   17篇
  2010年   7篇
  2009年   5篇
  2008年   10篇
  2007年   7篇
  2006年   12篇
  2005年   12篇
  2004年   5篇
  2003年   6篇
  2002年   6篇
  2001年   3篇
  2000年   1篇
  1999年   1篇
排序方式: 共有177条查询结果,搜索用时 15 毫秒
1.
2.
Ichthyoses are a common group of keratinization disorders. A non-inflammatory generalized persistent skin desquamation is observed. It is characterized by increased cell turnover, thickening of the stratum corneum and functional changes of sebaceous and sweat glands. All of these favor fungal proliferation. Dermatophytes may infect skin, hair and nails causing ringworm or tinea. They have the ability to obtain nutrients from keratinized material. One of its most prevalent genera is Trichophyton rubrum. Although tineas and ichthyoses are quite common, the association of the two entities is rarely reported in the literature. Three cases of ichthyosis associated with widespread infection by T. rubrum are presented. Resistance to several antifungal treatments was responsible for worsening of ichthyosis signs and symptoms.  相似文献   
3.
Background: Individuals with severe aphasia may fail to regain spoken language, so that treatment should target other communication modalities such as writing. There is relatively limited documentation of successful writing treatment, particularly in individuals with severe aphasia. Aims: The present study was designed to examine treatment outcomes in response to two writing treatment protocols intended to rebuild single-word vocabulary for written communication. Methods & Procedures: Writing treatments were implemented with four individuals who had significant aphasia and severe agraphia. Two participants received Anagram and Copy Treatment (ACT) which involved arrangement of component letters and repeated copying of target words, along with a homework programme called Copy and Recall Treatment (CART) that included copying and recall of target words. The other two participants received the homework-based CART only. Single-subject multiple-baseline designs were used with sets of words sequentially targeted for treatment. Outcomes & Results: All four participants responded positively to treatment. Three of the participants had severely limited spoken language, so that mastery of written words provided a much-needed means of communication. The fourth participant, who had adequate spoken language for face-to-face conversation, employed his improved spelling for written messages such as e-mail. Conclusions: Single-word writing abilities may improve with treatment despite long times post onset and persistent impairments to spoken language.  相似文献   
4.

Purpose

The purpose of this study was to estimate the association among the presence of subependymal nodules (SENs), subependymal giant cell tumours (SGCTs) and gene mutation in tuberous sclerosis complex (TSC) patients.

Methods

Clinical records and images of 81 TSC patients were retrospectively reviewed by two neuroradiologists in consensus. All patients were assessed for gene mutations and were categorized as TSC1 or TSC2 mutation carriers, or no-mutations-identified (NMI) patients. They underwent a brain magnetic resonance imaging (MRI) using 0.1 mmol/kg of gadobutrol. Any enhancing SEN?≥?1 cm and placed near the foramen of Monro was considered SGCT. Two MRI follow-up exams for each patient with SGCT were evaluated to assess tumour growth using Wilcoxon and chi-squared tests.

Results

Of 81 patients, 44 (54 %) were TSC2 mutation carriers, 20 (25 %) TSC1 and 17 (21 %) NMI. Nine (11 %) had a unilateral and three (4 %) a bilateral SGCT. Fifty of 81 patients (62 %) showed at least one SEN. None of the 31 patients without SEN showed SGCTs, whilst 12 (24 %) of the 50 patients with at least one SEN showed SGCTs (p?=?0.003). The association between the presence of SGCT or SEN and gene mutation was not significant (p?=?0.251 and p?=?0.187, respectively). At follow-up, the median SGCT diameter increased from 14 to 15 mm (p?=?0.017), whilst the median SGCT volume increased from 589 to 791 mm3 (p?=?0.006).

Conclusions

TSC patients with SENs are more likely to present with SGCT than those without SENs, in particular for TSC2 mutation carriers. The SGCT growth rate may be missed if based on the diameter instead of on the volume.  相似文献   
5.

Purpose

LDD is an important cause of low back pain. Many people believe there is an adverse influence of type 2 diabetes (T2D) on lumbar intervertebral disc degeneration (LDD). We examined a population sample for epidemiological evidence of association.

Methods

Twin volunteers from the TwinsUK cohort having spine magnetic resonance (MR) scans coded for LDD and information about T2D were investigated in two ways. First, as a population sample and second as a cotwin case control study in twin pairs discordant for T2D. Other risk factors for LDD considered were age, body-mass index (BMI), smoking, and alcohol.

Results

In 956 twin volunteers T2D had a prevalence of 6.6 %. LDD score was higher in T2D twins (14.9 vs 13.1 p = 0.04) but was not an independent risk factor if the influence of age and BMI were included in the model. Discordant twin analysis (n = 33 pairs) showed no significant difference in LDD between twins having T2D and their unaffected cotwins.

Conclusions

Twins having T2D did manifest higher LDD scores but the effect was abrogated once BMI was included in multivariable analysis, showing it is not an independent risk factor for LDD. The population study had 80 % power at 0.1 significance level to detect a difference of 1.8 in LDD score (range of 0–60), so if there is an effect of T2D on LDD, it is likely to be small.
  相似文献   
6.
7.
Multi-reactive centered reagents are beneficial in chemical synthesis due to their advantage of minimal material utilization and formation of less by-products. Trichloroisocyanuric acid (TCCA), a reagent with three reactive centers, was employed in the synthesis of spirooxindoles through the oxidative rearrangement of various N-protected tetrahydro-β-carbolines. In this protocol, low equivalents of TCCA were required to access spirooxindoles (up to 99% yield) with a wide substrate scope. Furthermore, the applicability and robustness of this protocol were proven for the gram-scale total synthesis of natural alkaloids such as (±)-coerulescine (1) and (±)-horsfiline (2) in excellent yields.

Three-reactive centered reagent (TCCA) mediated construction of spirooxindoles through an oxidative rearrangement of various N-protected tetrahydro-β-carbolines and total synthesis of natural alkaloids (±)-coerulescine and (±)-horsfiline.  相似文献   
8.
Stem cell therapy has been considered a promise for damaged myocardial tissue. We have previously shown that S-nitroso-N-acetyl-D,L-penicillamine (SNAP) increases the expression of several muscular markers and VEGF in mesenchymal stem cells, indicating that transplantation of SNAP-treated cells could provide better functional outcomes. Here, we transplanted SNAP-treated adipose tissue-derived stem cells (ADSCs) in rat infarcted myocardium. After 30 days, we observed a significant improvement of the ejection fraction in rats that received SNAP-treated ADSCs, compared with those that received untreated cells (p = 0.008). Immunohistochemical reactions showed an increased expression of troponin T–C and von Willebrand factor, and organized vascular units in the infarcted area of tissue transplanted with treated ADSCs. SNAP exposure induced intracellular S-nitrosation, a decreased GSH/GSSG ratio, but did not increase cGMP levels. Collectively, these results indicate that SNAP alters the redox environment of ADSCs, possibly associated with a pre-differentiation state, which may improve cardiac function after transplantation.  相似文献   
9.
Glutaric acidemia type I (GA-I) is an inherited metabolic disease characterized by accumulation of glutaric acid (GA) and striatal degeneration. Although growing evidence suggests that excitotoxicity and oxidative stress play central role in the neuropathogenesis of this disease, mechanism underlying striatal damage in this disorder is not well established. Thus, we decided to investigate the in vitro effects of GA 10 nM (a low concentration that can be present initial development this disorder) on l-[3H]glutamate uptake and reactive oxygen species (ROS) generation in synaptosomes from striatum of rats. GA reduced l-[3H]glutamate uptake in synaptosomes from 1 up to 30 min after its addition. Furthermore, we also provided some evidence that GA competes with the glutamate transporter inhibitor l-trans-pyrrolidine-2,4-dicarboxylate (PDC), suggesting a possible interaction of GA with glutamate transporters on synaptosomes. Moreover, GA produced a significant decrease in the VMAX of l-[3H]glutamate uptake, but did not affect the KD value. Although the GA did not show oxidant activity per se, it increased the ROS generation in striatal synaptosomes. To evaluate the involvement of reactive species generation in the GA-induced l-[3H]glutamate uptake inhibition, trolox (0.3, 0.6 and 6 μM) was added on the incubation medium. Statistical analysis showed that trolox did not decrease inhibition of GA-induced l-[3H]glutamate uptake, but decreased GA-induced reactive species formation in striatal synaptosomes (1, 3, 5, 10, 15 and 30 min), suggesting that ROS generation appears to occur secondarily to glutamatergic overstimulation in this model of organic acidemia. Since GA induced DCFH oxidation increase, we evaluate the involvement of glutamate receptor antagonists in oxidative stress, showing that CNQX, but not MK-801, decreased the DCFH oxidation increase in striatal synaptosomes. Furthermore, the results presented in this report suggest that excitotoxicity elicited by low concentration of GA, could be in part by maintaining this excitatory neurotransmitter in the synaptic cleft by non-competitive inhibition of glutamate uptake. Thus the present data may explain, at least partly, initial striatal damage at birth, as evidenced by acute bilateral destruction of caudate and putamen observed in children with GA-I.  相似文献   
10.
PURPOSE: This study analyzed the continued nursing education process in three university hospitals in southern Brazil. Its theoretical reference was centered upon the problematization pedagogy of Freire and the levels of practice of Vázquez. METHODS: This was a qualitative case study, based on multiple holistic cases. The data were collected through document analysis, observation of scenarios, and semistructured interviews with 22 nursing employees. RESULTS: The thematic analysis evidenced the continued nursing education process, highlighting initiatives such as the creation of the Center for Nursing Education and Research, the Permanent Nursing Education Center, and the Continued Nursing Education Program. CONCLUSION: This study serves as an important tool for the transformation of the reality of health care subjects and institutions.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号