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   95篇
  免费   4篇
耳鼻咽喉   1篇
儿科学   6篇
妇产科学   4篇
基础医学   23篇
口腔科学   3篇
临床医学   6篇
内科学   17篇
皮肤病学   2篇
神经病学   6篇
特种医学   1篇
外科学   14篇
综合类   1篇
预防医学   2篇
眼科学   1篇
药学   6篇
中国医学   1篇
肿瘤学   5篇
  2023年   4篇
  2022年   7篇
  2021年   13篇
  2020年   4篇
  2019年   8篇
  2018年   1篇
  2017年   4篇
  2016年   7篇
  2015年   6篇
  2014年   8篇
  2013年   8篇
  2012年   5篇
  2011年   9篇
  2010年   5篇
  2009年   2篇
  2008年   3篇
  2006年   1篇
  2003年   2篇
  2002年   2篇
排序方式: 共有99条查询结果,搜索用时 15 毫秒
1.
COVID-19 pandemic leads to health challenges globally, and its diverse aspects need to be uncovered. Multi-organ injuries have been reported by describing potential SARS-CoV-2 entrance routes: ACE2 and TMPRSS2. Since these cell surface receptors’ expression has been disclosed within the male reproductive system, its susceptibility to being infected by SARS-CoV-2 has been summarised through this literature review. Expression of ACE2 and TMPRSS2 at RNA or protein level has been reported across various investigations indicates that the male genitalia potentially is vulnerable to SARS-CoV-2 infection. Presence of SARS-CoV-2 within semen samples and following direct viral damage, secondary inflammatory response causing orchitis or testicular discomfort and finally the amount of viral load leading testicular damage and immune response activation are among probable underlying mechanisms. Therefore, genital examination and laboratory tests should be considered to address the male reproductive tract complications and fertility issues.  相似文献   
2.
3.
Abstract

In Iran, breast cancer (BC) is the most prevalent cancer among women. The standard treatment for this cancer is partial or total removal of breast tissue, followed by chemotherapy and radiation. Tissue engineering (TE) has made new treatments for tissue loss in these patients by creating functional substitutes in the laboratory. In addition, cancer biology combined with TE provides a new strategy for evaluation of anti-BC therapy. Several innovations in TE have led to the design of scaffold or matrix based culture systems that more closely mimic the native extracellular matrix (ECM). Currently, engineered three-dimensional (3D) cultures are being developed for modelling of the tumour microenvironment. These 3D cultures fulfil the need for in vitro approaches that allow an accurate study of the molecular mechanisms and a better analysis of the drugs effect. In the present study, we review recent developments in utilising of TE in BC. Moreover, this review describes achievements of Iranian researchers in the field of breast TE.  相似文献   
4.
Background: There is a high risk of tuberculosis (TB) disease diagnosis among conventional methods.Objectives:This study is aimed at diagnosing TB using hybrid machine learning approaches.Materials and Methods: Patient epicrisis reports obtained from the Pasteur Laboratory in the north of Iran were used. All 175 samples have twenty features. The features are classified based on incorporating a fuzzy logic controller and artificial immune recognition system. The features are normalized through a fuzzy rule based on a labeling system. The labeled features are categorized into normal and tuberculosis classes using the Artificial Immune Recognition Algorithm.Results:Overall, the highest classification accuracy reached was for the 0.8 learning rate (α) values. The artificial immune recognition system (AIRS) classification approaches using fuzzy logic also yielded better diagnosis results in terms of detection accuracy compared to other empirical methods. Classification accuracy was 99.14%, sensitivity 87.00%, and specificity 86.12%.  相似文献   
5.
Regular exercise has beneficial effects on cerebrovascular diseases; however, its biochemical mechanisms are not fully known. The purpose of this study was to determine antioxidant enzyme activities and lipid peroxidation of both hippocampi after applying exercise followed by occluding one common carotid. Wistar rats were divided into four groups of control, exercise, hypoperfusion and exercise–hypoperfusion (exe-hypo). In the exercise and exe-hypo groups, the rats were forced to run on a treadmill for 1 h a day for 2 months. The right common carotid of the animals in the (exe-hypo) group was occluded after the cessation of exercise. Surgery without occlusion of the carotid was applied on the control (without exercise) and exercise groups. All animals were sacrificed 1 and 24 h after surgery. The levels of malondialdehyde (MDA) and antioxidant enzyme activities in the hippocampi were measured. A significant interaction was observed between the exercise and hypoperfusion in both hippocampi (p < 0.05). In comparison with the control group, there was significant elevation of catalase activity in the right and left hippocampus of the hypo group at 24 h (p < 0.0001). Regarding the differences between the hemispheres, there was a significant increase in MDA and decrease in catalase activity in the left hippocampus in hypoperfusion group, but the exercise in the exe-hypo group succeeded in abolishing these alterations which were caused by hypoperfusion, This study shows that exercise pre-conditioning prevents some alterations in brain oxidant–antioxidant status which are induced by cerebral hypoperfusion. Further studies are needed in order to clarify the mechanism of exercise.  相似文献   
6.
Citation
Jeddi‐Tehrani M, Torabi R, Zarnani AH, Mohammadzadeh A, Arefi S, Zeraati H, Akhondi MM, Chamani‐Tabriz L, Idali F, Emami S, Zarei S. Analysis of plasminogen activator inhibitor‐1, integrin beta3, beta fibrinogen and methylenetetrahydrofolate reductase polymorphisms in Iranian women with recurrent pregnancy loss. Am J Reprod Immunol 2011; 66: 149–156 Problem To identify the associations of the plasminogen activator inhibitor‐1 (PAI‐1) ?675 4G/5G, beta fibrinogen (BF) ?455G/A, integrin beta 3 (ITGB3) 1565T/C, and methylenetetrahydrofolate reductase (MTHFR) 677C/T and 1298A/C polymorphisms with recurrent pregnancy loss (RPL). Method of study Polymerase chain reaction and restriction fragment length polymorphism (PCR‐RFLP) were performed to assess the frequency of five candidate genetic risk factors for RPL, and the frequencies of the polymorphisms were calculated and compared between case and control groups. Results The BF ?455G/A, MTHFR 677C/T, and 1298A/C polymorphisms were found to be positively, and ITGB3 1565T/C polymorphism negatively, associated with RPL. Homozygosity but not heterozygosity for PAI‐1 ?675 4G/5G polymorphism was significantly higher in patients with RPL than in the control group. The presence of both mutations of MTHFR genes highly increased the risk of RPL. Conclusion The data highlight the importance of thrombophilia screening in patients with RPL.  相似文献   
7.

INTRODUCTION:

Cardiovascular disease is one of the main causes of mortality and morbidity in diabetic patients. This study evaluated the effects of diabetes on myocardial capillary density and several serum angiogenic factors including nitric oxide, vascular endothelial growth factor, and soluble vascular endothelial growth factor receptors.

METHODS:

Twelve male rats were divided into two groups: control and diabetic (n = 6 each). Diabetes was induced with a single dose of streptozotocin (50 mg/kg). After 21 days, capillary density in the myocardial tissue was evaluated using immunohistochemical staining and is reported as capillaries per mm2. Blood samples were collected before and after the induction of diabetes.

RESULTS:

In the diabetic group, serum nitric oxide and soluble vascular endothelial growth factor receptor 2 concentrations were lower than the levels in the control group, while the level of soluble vascular endothelial growth factor receptor 1 was significantly higher. There was no significant change in the serum vascular endothelial growth factor concentration between the diabetic and control groups; however, the ratio of vascular endothelial growth factor to vascular endothelial growth factor receptor 1 was significantly lower in the diabetic animals. The myocardial capillary density was also lower in the diabetic group compared with the control group (1549±161 vs. 2156±202/mm2, respectively).

CONCLUSION:

Reduced serum nitric oxide and vascular endothelial growth factor receptor 2 levels, increased serum vascular endothelial growth factor receptor 1 levels and a lower vascular endothelial growth factor to vascular endothelial growth factor receptor 1 ratio may be responsible for the decreased myocardial capillary density in diabetic rats.  相似文献   
8.
BACKGROUNDThere is recently a concern regarding the reinfection and reactivation of previously reCoVered coronavirus disease 2019 (CoVID-19) patients.AIMTo summarize the recent findings and reports of CoVID-19 reinfection in patients previously reCoVered from the disease.METHODSThis study was a systematic review of current evidence conducted in August 2020. The authors studied the probable reinfection risk of novel coronavirus (CoVID-19). We performed a systematic search using the keywords in online databases. The investigation adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist to ensure the reliability and validity of this study and results.RESULTSWe reviewed 31 studies. Eight studies described reCoVered patients with reinfection. Only one study reported reinfected patients who died. In 26 studies, there was no information about the status of the patients. Several studies indicated that reinfection is not probable and that post-infection immunity is at least temporary and short.CONCLUSIONBased on our review, we concluded that a positive polymerase chain reaction retest could be due to several reasons and should not always be considered as reinfection or reactivation of the disease. Most relevant studies in positive retest patients have shown relative and probably temporary immunity after the reCoVery of the disease.  相似文献   
9.
10.
Abnormal dilatation and tortuosity of the pampiniform plexus within the spermatic cord are termed varicocele which leads to impaired spermatogenesis due to heat‐related oxidative stress and cell death. Previously, it was shown that both apoptosis and autophagy pathways were activated by heat in germ cells of mouse in vivo and in vitro. But, status of these pathways is not clear in chronic state of heat stress such as varicocele. Therefore, we aimed to access sperm apoptotic markers (active caspases 3/7 and DNA fragmentation), and autophagic markers (Atg7 and LC3 proteins) as primary outcomes, and also sperm parameters and protamine deficiency as secondary outcomes between 23 infertile men with varicocele and 16 fertile individuals. Sperm parameters were assessed according to World Health Organization 2010 protocol. Apoptotic markers (active caspases 3/7 and DNA fragmentation), autophagic markers (Atg7 and LC3 proteins), and protamine deficiency were evaluated by flow cytometry, fluorescence microscope, and western blotting techniques. Mean of autophagy and apoptosis markers, and also protamine deficiency have significantly increased in infertile men with varicocele compared to fertile individuals, but autophagy and apoptosis markers did not significantly correlate with each other. In conclusion, it seems that both apoptosis and autophagy pathways are independently active in spermatozoa of infertile men with varicocele.  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