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   568篇
  免费   19篇
  国内免费   2篇
耳鼻咽喉   3篇
儿科学   27篇
妇产科学   25篇
基础医学   93篇
口腔科学   10篇
临床医学   71篇
内科学   108篇
皮肤病学   12篇
神经病学   31篇
特种医学   8篇
外科学   53篇
综合类   13篇
预防医学   45篇
眼科学   14篇
药学   47篇
中国医学   6篇
肿瘤学   23篇
  2024年   1篇
  2023年   10篇
  2022年   17篇
  2021年   36篇
  2020年   15篇
  2019年   34篇
  2018年   33篇
  2017年   19篇
  2016年   25篇
  2015年   28篇
  2014年   34篇
  2013年   38篇
  2012年   74篇
  2011年   55篇
  2010年   25篇
  2009年   19篇
  2008年   31篇
  2007年   23篇
  2006年   28篇
  2005年   17篇
  2004年   10篇
  2003年   3篇
  2002年   5篇
  2000年   1篇
  1999年   3篇
  1997年   2篇
  1996年   2篇
  1982年   1篇
排序方式: 共有589条查询结果,搜索用时 15 毫秒
11.
Rahimi Z  Nourozi-Rad R 《Angiology》2012,63(2):131-137
There are conflicting reports about the association of endothelial nitric oxide synthase (eNOS) gene polymorphism and the risk of coronary artery disease (CAD). To determine the frequency of eNOS G894T variant and to find the possible association between this polymorphism with CAD we studied 207 unrelated patients with total CAD (with and without diabetes) and 92 controls. The eNOS variants were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The presence of GT + TT genotype was associated with 2.1-fold (P = .006), 2.29-fold (P = .006), and 1.93-fold (P = .032) increased risk of CAD in total CAD, CAD with diabetes, and in CAD without diabetes patients, respectively. The presence of T allele of eNOS increased the risk of CAD 2.15-fold (P = .001). The levels of low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG) tended to be higher in patients carrier for T allele compared to those with G allele. The results of present study revealed that eNOS G894T polymorphism is associated with increased risk of CAD in our population.  相似文献   
12.
BackgroundDeep brain stimulation (DBS) has emerged as a potential therapeutic strategy in the treatment of neurological disorders including epilepsy. However, the cellular mechanism responsible for the effects of DBS remains largely undefined. Therefore, using electrophysiological approach, we aimed to determine the antiepileptic effects and restorative potential of low frequency stimulation (LFS) on amygdala kindling-induced changes in electrophysiological properties of rat hippocampal CA1 pyramidal neurons.MethodsAnimals were kindled by electrical stimulation of amygdala in a rapid kindling manner (12 times per day). In one group of animals, immediately after termination of daily 12 rapid kindling stimulations, the kindling site was subjected to 4 packages of LFS at intervals of 5 min (each package contained 200 monophasic square-wave pulses, 0.1 ms pulse duration at 1 Hz). Whole cell patch clamp recording under current clamp conditions was performed on visually identified pyramidal neurons in hippocampal slice preparations obtained from amygdala-kindled rats and the rats receiving LFS.ResultsKindling of the right basolateral amygdala profoundly affected spontaneous firing behavior and repetitive discharge characteristics of pyramidal neuronal electrophysiological properties. Application of LFS at the kindling site almost completely prevented the development of epilepsy and the disruptive effects of kindling on neuronal electrical activity through restoration of the normal electrophysiological characteristics.ConclusionsThe results of this study implied that application of LFS during kindling acquisition prevents the kindling induced changes in functional electrical properties of CA1 pyramidal neurons, suggesting that this action may be involved in the antiepileptogenic mechanism of LFS.  相似文献   
13.
14.
Wiener Medizinische Wochenschrift - Infection prevention protocols are the accepted standard to control nosocomial infections. These protective measures intensified after the coronavirus 2019...  相似文献   
15.
Introduction: There are some evidences indicating DNA damage by oxidant and mutant agents has an essential role in the chronic renal failure and end stage renal disease (ESRD). To investigate the possible association of GSTs variants with ESRD, we investigated the frequency of GST- T1, M1, and P1 genotypes, and the level of malondialdehyde (MDA) in patients with ESRD.

Materials and methods: The present case-control study consisted of 136 ESRD patients treated with maintenance hemodialysis and 137 gender- and age-matched, unrelated healthy controls from the population of west of Iran. The GST- T1, M1, and P1 genotypes were determined in all individuals using multiplex-PCR and PCR-RFLP. The level of MDA was measured by high-performance liquid chromatography (HPLC).

Results: We found that GSTM1 and GSTT1 null genotypes (GSTT1?/GSTM1?) increased the risk of ESRD by 1.8 times (p?<?0.001) and the increased risk of ESRD for GSTM-null (T1+-M1?) genotype was 3.04 times (p?=?0.002). ESRD patients carriers the GST (GSTM1-null?+?GSTT1-null?+?GST-null) genotypes compared to GST normal genotype increased the risk of ESRD by 3.3 (p?<?0.001) times. ESRD patients carriers of GST-null, GSTM1-null, and GSTT1-null genotypes had greater MDA concentration compared with the same genotypes of control subjects. Our results indicated that the GST-null allele (GSTT1-null/GSTM1-null) is a risk factor for ESRD and carriers of this allele have high levels of MDA.

Conclusion: Our findings indicate that oxidative stress, impairment of the antioxidant system and abnormal lipid metabolism may play a role in the pathogenesis and progression of ESRD and its related complications. These data suggest that patients with ESRD are more susceptible to vascular diseases.  相似文献   
16.

Background

Multiple sclerosis (MS) is a debilitating and life-long disease that affects the sexual life of people. However, in Iran little attention has been paid to the sexual life of women with MS.

Objective

The aim of this study was to understand the sexual life and experiences of Iranian women with multiple sclerosis.

Methods

A qualitative study was designed, and face-to-face semi-structured interviews were conducted with twenty-five women with MS. The interviews were tape-recorded and transcribed verbatim. Data were analyzed using a content analysis approach and through MAXQDA.10 software.

Results

The main themes identified during the analysis were: (1) limited sexual activity, (2) sex life behind the mask, and (3) lack of sexual support during the rehabilitation process. In fact, the participants in this study expressed that their sexual activity was negatively affected by MS. They were trying to hide their sexual problems, and present themselves to their husbands differently from what they are, which can be considered as sex life behind the mask. Furthermore, Iranian women with MS received little sexual support from the rehabilitation team.

Conclusions

Hiding sexual problems from husbands is thought to be a common practice and behavior among Iranian women with MS. Understanding this insight and its consequences can assist the rehabilitation team in helping and solving sexual problems of women with MS. Moreover, sexual awareness and education should be extended, especially among the husbands of women with MS.  相似文献   
17.
Toxic elements are commonly used in cosmetic products for many reasons like coloring pigments or blocking ultraviolet light; however, the level of some metals exceed specific concentration which can cause serious safety issues. This study aims to evaluate the content of lead and cadmium in samples of sunscreen and foundation creams, most frequently used brands of cosmetic products, in Iran. Concentration of lead in the sunscreens and foundation creams was lower than that of USFDA standards. The content of cadmium was higher than Europe Union standard. Effort must be made to inform the users about the harmful consequences of cosmetics.  相似文献   
18.
19.

Background

Entamoeba moshkovskii and E. dispar are impossible to differentiate microscopically from the pathogenic species E. histolytica. Multiplex polymerase chain reaction (Multiplex PCR) is a widespread molecular biology technique for amplification of multiple targets in a single PCR experiment.

Methods

For detection and differentiation of the three-microscopy indistinguishable Entamoeba species in human, multiplex PCR assay using different DNA extraction methods was studied. A conserved forward primer was derived from the middle of the small-subunit rRNA gene, and reverse primers were designed from signature sequences specific to each of these three Entamoeba species.

Results

A 166-bp PCR product with E. histolytica DNA, a 580-bp product with E. moshkovskii DNA and a 752-bp product with E. dispar DNA were generated in a single-round and multiplex PCR reaction.

Conclusion

We recommend this PCR assay as an accurate, rapid, and effective diagnostic method for the detection and discrimination of these three Entamoeba species in both routine diagnosis of amoebiasis and epidemiological surveys.  相似文献   
20.
Aim of the workTo assess the outcome of planned pregnancies in patients with systemic lupus erythematosus (SLE). Patients and methods: The study was conducted on 32 patients. The medical management included pre-pregnancy planning at the quiescent phase of the disease and after at least six months of clinical remission. The patients had a monthly visit during pregnancy and three months post-delivery. Disease flare was characterized by the recurrence of symptoms and signs in different organs, as well as the need for an increase in medication dose. Results: There were 36 planned pregnancies in 32 patients, of which 15 and 17 cases were primiparous and multiparous, respectively. The SLE flares were observed in 36.1% of the cases, 8.3% of which developed postpartum; moreover, they were moderate in severity and mostly involved the kidneys and joints. Pregnancy outcomes included18 (50%) cases ended in term labor; 13 (36.1%) pregnancies had preterm labor, and 5 (13.8%) pregnancies terminated with abortions. Furthermore, obstetric complications included 2(6.5%) patients with premature rupture of membranes, 5(15.6%) fetuses with intrauterine growth retardation, and 2(6.4%) mothers with preeclampsia. 10(27.7%) pregnancies occurred in patients with lupus nephritis. Cesarean section was performed on 24(77.4%) patients, and low birth weight was observed in 7(21.8%) infants. None of the infants had neonatal lupus, congenital deformities or infection. Conclusion: Pre-pregnancy planning in patients with SLE can considerably improve pregnancy outcomes. Neonatal lupus, congenital anomalies or infection were not present. SLE patients intending to become pregnant should be provided with close medical supervision for a safe maternal and fetal outcome.  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