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   608篇
  免费   52篇
  国内免费   4篇
耳鼻咽喉   2篇
儿科学   21篇
妇产科学   14篇
基础医学   110篇
口腔科学   20篇
临床医学   53篇
内科学   106篇
皮肤病学   17篇
神经病学   35篇
特种医学   28篇
外科学   95篇
综合类   7篇
一般理论   3篇
预防医学   62篇
眼科学   6篇
药学   30篇
中国医学   2篇
肿瘤学   53篇
  2023年   6篇
  2022年   15篇
  2021年   38篇
  2020年   23篇
  2019年   21篇
  2018年   25篇
  2017年   13篇
  2016年   28篇
  2015年   28篇
  2014年   31篇
  2013年   37篇
  2012年   53篇
  2011年   41篇
  2010年   33篇
  2009年   24篇
  2008年   38篇
  2007年   44篇
  2006年   19篇
  2005年   22篇
  2004年   24篇
  2003年   24篇
  2002年   9篇
  2001年   4篇
  2000年   10篇
  1999年   6篇
  1998年   2篇
  1997年   3篇
  1996年   5篇
  1995年   5篇
  1994年   2篇
  1993年   3篇
  1992年   2篇
  1991年   4篇
  1990年   1篇
  1989年   2篇
  1988年   1篇
  1987年   2篇
  1986年   3篇
  1985年   1篇
  1984年   1篇
  1983年   1篇
  1981年   1篇
  1977年   2篇
  1974年   1篇
  1972年   2篇
  1948年   1篇
  1935年   1篇
  1933年   1篇
  1927年   1篇
排序方式: 共有664条查询结果,搜索用时 31 毫秒
21.
Interferon‐induced transmembrane protein 3 (IFITM3) ?plays a crucial role in the antiviral responses of Type I interferons (IFNs). The role of IFITM3 in the central nervous system (CNS) is, however, largely unknown, despite the fact that its expression is increased in the brains of patients with neurologic and neuropsychiatric diseases. Here, we show the role of IFITM3 in long‐lasting neuronal impairments in mice following polyriboinosinic‐polyribocytidylic acid (polyI:C, a synthetic double‐stranded RNA)‐induced immune challenge during the early stages of development. We found that the induction of IFITM3 expression in the brain of mice treated with polyI:C was observed only in astrocytes. Cultured astrocytes were activated by polyI:C treatment, leading to an increase in the mRNA levels of inflammatory cytokines as well as Ifitm3. When cultured neurons were treated with the conditioned medium of polyI:C‐treated astrocytes (polyI:C‐ACM), neurite development was impaired. These polyI:C‐ACM‐induced neurodevelopmental abnormalities were alleviated by ifitm3?/? astrocyte‐conditioned medium. Furthermore, decreases of MAP2 expression, spine density, and dendrite complexity in the frontal cortex as well as memory impairment were evident in polyI:C‐treated wild‐type mice, but such neuronal impairments were not observed in ifitm3?/? mice. We also found that IFITM3 proteins were localized to the early endosomes of astrocytes following polyI:C treatment and reduced endocytic activity. These findings suggest that the induction of IFITM3 expression in astrocytes by the activation of the innate immune system during the early stages of development has non‐cell autonomous effects that affect subsequent neurodevelopment, leading to neuropathological impairments and brain dysfunction, by impairing endocytosis in astrocytes. GLIA 2013  相似文献   
22.
Prostanoids generated by COX-2 are involved in the regulation of inflammation but their exact role in the innate immune response has not been defined. We investigated whether COX-2 is involved in host defense against Pseudomonas aeruginosa pneumonia. In vitro studies, in a macrophage cell line, showed that cytotoxic strain of P aeruginosa (PA103) induced significant COX-2 protein expression and enzymatic function. In vivo data showed that infection with PA103 increased COX-2 protein production in whole lung tissue compared to mice that were infected with mutant bacteria that lack ExoU (DeltaU) or ExoU and ExoT (DeltaUT). COX-2(-/-) mice had accentuated clearance of cytotoxic P. aeruginosa from the lungs. We further tested the effects of COX-2 products such as prostaglandin E(2) on the function of phagocytic cells. Our studies indicate that prostaglandin E(2) may be involved through interacting with the EP2 receptors in modulating the host response because treatment of macrophages with prostaglandin E(2) suppressed production of reactive oxygen species. Furthermore there was enhanced bacterial clearance in EP2 receptor(-/-) mice compared to the wild-type controls. Thus it is possible that inhibition of COX-2 or EP2 receptors could be an effective adjunctive treatment for severe or resistant P. aeruginosa pneumonia.  相似文献   
23.
24.
OBJECTIVE: Glyburide is the most widely used sulfonylurea but has unique pharmacodynamic properties that may increase harm. We hypothesized that glyburide causes more hypoglycemia and cardiovascular events than other secretagogues or insulin. RESEARCH DESIGN AND METHODS: Data sources were Medline, Embase, Cochrane, and three other web-based clinical trial registers (1966-2005). Parallel, randomized, controlled trials in people with type 2 diabetes comparing glyburide monotherapy with monotherapy using secretagogues or insulin were selected. Outcomes were hypoglycemia, glycemic control, cardiovascular events, body weight, and death. Titles and abstracts of 1,806 publications were reviewed in duplicate and 21 relevant articles identified. Data on patient characteristics, interventions, outcomes, and validity were extracted in duplicate using predefined criteria. RESULTS: Glyburide was associated with a 52% greater risk of experiencing at least one episode of hypoglycemia compared with other secretagogues (relative risk 1.52 [95% CI 1.21-1.92]) and with 83% greater risk compared with other sulfonylureas (1.83 [1.35-2.49]). Glyburide was not associated with an increased risk of cardiovascular events (0.84 [0.56-1.26]), death (0.87 [0.70-1.07]), or end-of-trial weight (weighted mean difference 1.69 kg [95% CI -0.41 to 3.80]) compared with other secretagogues. Limitations included suboptimal reporting of original trials. Loss to follow-up exceeded 20% in some studies, and major hypoglycemia was infrequently reported. CONCLUSIONS: Glyburide caused more hypoglycemia than other secretagogues and other sulfonylureas. Glyburide was not associated with an increased risk of cardiovascular events, death, or weight gain.  相似文献   
25.
Compared with other breast cancer subtypes, patients with triple‐negative breast cancer (TNBC), and irrespective to their disease stage, were always recognized to have the worst overall survival data. Although this does not seem different at the present time, yet the last few years have witnessed many breakthrough genomic and molecular findings, that could dramatically improve our understanding of the biological complexity of TNBC. Based on genomic analyses, it was consistently evident that TNBC comprises a heterogeneous group of cancers, which have numerous diverse molecular aberrations. This—in return—has provided a platform for a new generation of clinical trials using many innovative therapies, directed against such novel targets. At the present time, two PARP inhibitors and one anti‐PD‐L1 monoclonal antibody (in combination with chemotherapy) have been approved in certain subpopulations of metastatic TNBC (mTNBC) patients, which have finally brought this disease into the era of personalized medicine. In the current review, we will explore the genomic landscape of TNBC, through which many actionable targets were graduated. We will also discuss the results of the key—practice changing—clinical studies, and some upcoming personalized treatment options for patients with mTNBC, that may be clinically adopted in the near future.  相似文献   
26.
Incidence of inadvertent arterial puncture secondary to central venous catheter insertion is not common with an arterial puncture rate of<1%.This is due to the advancements and wide availability of ultrasound to guide its insertion.Formation of arteriovenous fistula after arterial puncture is an unexpected complication.Till date,only five cases(including this case)of acquired arteriovenous fistula formation has been described due to inadvertent common carotid puncture.The present case is a 26-year-old man sustained traumatic brain injuries,chest injuries and multiple bony fractures.During resuscitative phase,attempts at left central venous catheter via left internal jugular vein under ultrasound guidance resulted in inadvertent puncture into the left common carotid artery.Surgical neck exploration revealed that the catheter had punctured through the left internal jugular vein into the common carotid artery with formation of arteriovenous fistula.The catheter was removed successfully and common carotid artery was repaired.Postoperatively,the patient recovered and clinic visits revealed no neurological deficits.From our literature review,the safest method for removal is via endovascular and open surgical removal.The pull/push technique(direct removal with compression)is not recommended due to the high risk for stroke,bleeding and hematoma formation.  相似文献   
27.
In this study, the regional rat brain distribution of radioiodinated o‐iodo‐trans‐decalinvesamicol ([125I]OIDV) was determined in vivo to evaluate its potential as a single‐photon emission computed tomography (SPECT) imaging probe for vesicular acetylcholine transporter (VAChT). Following intravenous injection, [125I]OIDV passed freely across the blood–brain barrier and accumulated in rat brain. The accumulation of [125I]OIDV in rat brain was significantly reduced by coadministration of (+/?)‐vesamicol (0.125 µmol). In contrast, the coadministration of σ‐receptor ligands, such as (+)‐pentazocine (0.125 µmol) as a σ‐1 receptor ligand and (+)?3‐(3‐hydroxyphenyl)‐N‐propylpiperidine (0.125 µmol) as a σ‐1 and σ‐2 receptor ligands, barely affected the accumulation of [125I]OIDV in rat brain. These findings in vivo were corroborated by autoradiographic analysis ex vivo. The authors found that the tracer binds with pharmacological selectivity to VAChT in rat brain and predicted that it may likewise serve in translational SPECT imaging studies of this marker in the integrity of cholinergic innervations. Synapse 68:107–113, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
28.

Background

The T594M variant of the β-subunit of the sodium epithelial channel (ENaC) gene may contribute to hypertension in individuals of Indo-Aryan origin.

Methods

Present study was performed to assess the role of the ENaC gene variant as an independent risk factor for hypertension in subjects of Indo-Aryan ancestry. A total of 150 patients of recently detected essential hypertension and 150 matched controls were genotyped for the T594M polymorphism of the ENaC gene by PCR–RFLP method.

Results

β-T594M mutation was found to be non-polymorphic. There was major genotype call in both the groups i.e. cases and controls. Other phenotypic parameters like age, sex and body mass index were also similar among hypertensive patients and controls (P > 0.05). Hypertensive patients had significantly higher total cholesterol and triglycerides compared with controls (P < 0.0001).

Conclusion

These results do not suggest an important role for the T594M variant of the ENaC gene contributing to either the development or severity of hypertension in subjects of Indo-Aryan ancestry.  相似文献   
29.

Purpose

As central nervous system (CNS) tumors account for second most common childhood malignancies and the first cause of mortality in children with cancer, improving treatment modalities can lead to increase the health care of patients. In this study, we examined the prevalence of childhood brain tumors in patients who referred to MAHAK’s Pediatric Cancer Treatment and Research Center (MPCTRC) for treatment.

Methods

A retrospective review of all children less than 15 years old with a CNS histologically proven tumor, who presented to MPCTRC from April 2007 to April 2010, was performed. Data was analyzed by SPSS version 19 with Kolmogorov–Smirnov and Chi-square tests.

Results

There were 198 (124 boys) children eligible for the study. The majority of the tumors were infratentorial (n?=?134), and the rest were supratentorial (n?=?60) and spinal (n?=?4) cases. The median age was 6.11?±?3.65 years old. Medulloblastoma (n?=?66), low-grade glioma (n?=?52), and high-grade glioma (n?=?40) were the most common tumors. The mean duration of follow-up was 21 months. At the time of this analysis, there were 105 (53 %) children alive, 82 (41.4 %) deaths, and 11 (5.6 %) lost for follow-up. The survival rate was 51.68?±?5.22 %.

Conclusions

In contrast of high rate of death in this study, other general characteristics can serve as benchmark for improving our care for children with brain tumors in Iran.  相似文献   
30.
How to cite this article: Siddiqui S, Ahmed A, Azim A. Selecting Journal for Publication in the Era of “Haste Predatory Journals and COVID-19”. Indian J Crit Care Med 2020;24(12):1284–1285.  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