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   348篇
  免费   23篇
  国内免费   2篇
耳鼻咽喉   1篇
儿科学   3篇
妇产科学   9篇
基础医学   26篇
口腔科学   16篇
临床医学   21篇
内科学   57篇
皮肤病学   3篇
神经病学   53篇
特种医学   14篇
外科学   56篇
综合类   5篇
预防医学   61篇
眼科学   3篇
药学   36篇
肿瘤学   9篇
  2023年   3篇
  2022年   2篇
  2021年   13篇
  2020年   9篇
  2019年   7篇
  2018年   13篇
  2017年   10篇
  2016年   7篇
  2015年   16篇
  2014年   14篇
  2013年   23篇
  2012年   33篇
  2011年   30篇
  2010年   22篇
  2009年   19篇
  2008年   26篇
  2007年   23篇
  2006年   26篇
  2005年   21篇
  2004年   14篇
  2003年   16篇
  2002年   15篇
  2001年   1篇
  2000年   4篇
  1999年   1篇
  1998年   1篇
  1993年   1篇
  1992年   2篇
  1989年   1篇
排序方式: 共有373条查询结果,搜索用时 15 毫秒
1.
OBJECTIVE: Oligoastrocytomas (OA) are mixed gliomas with distinct oligodendroglial and astrocytic neoplastic components. Very little about OA has been reported in the intractable epilepsy population. METHODS: We undertook a retrospective review of 923 patients who underwent resective surgery for intractable epilepsy between 1996 and 2004. RESULTS: 6/923 (0.7%) patients were diagnosed with OA. Five patients were female, one was male. Median age at diagnosis was 25 years (range 19-44 years). Tumors arose from the left side in all patients and from the temporal lobe in five patients. Three patients had complex partial seizures. Median length of refractory epilepsy prior to surgery was 10.5 years (range 1-28 years), and the median number of antiepileptic drugs used was 2 (range 1-10). Preoperative WADA testing for language and memory localization was done for three patients; preoperative stereotactical localization was done for three patients. Surgical pathology revealed low-grade OA (WHO II) in five patients, and anaplastic OA in one. There were no surgical complications, clinical or radiographic tumor recurrence at a mean follow up period of 3.2 years (range 2-8). Excellent seizure freedom was achieved in 5/6 patients. CONCLUSION: As a result of our small sample size, general conclusions may be imprecise, but this review suggests that OA behave similar to other tumors related to intractable epilepsy: they usually have a preoperative seizure course of many years, an excellent rate of seizure-freedom following surgery, and are in general, low-grade tumors with an indolent course for which serial imaging is sufficient follow-up.  相似文献   
2.
A simple and cost-effective diagnostic tool (TB Screen Test) for the screening of patients with pulmonary and extrapulmonary tuberculosis and for differentiation of those individuals from individuals without tuberculosis, other common infections, and healthy controls has been developed. The serological responses of purified mycobacterial glycolipid antigens were examined by a liposome agglutination assay. The assay was able to detect very low antiglycolipid antibody concentrations in the infected individuals. The sera from the tuberculosis patient group had significantly higher concentrations of antiglycolipid antibody than the sera from uninfected control subjects, with 94% sensitivity and 98.3% specificity. Glycolipids of Mycobacterium tuberculosis H37Rv antigens were isolated, purified, and characterized. After interchelation with liposome particles, these purified antigens specifically bound to the antiglycolipid antibodies present in the sera of patients with tuberculosis, resulting in the formation of a blue agglutination. This protocol clearly differentiates healthy controls and M. bovis BCG-vaccinated subjects from those with active tuberculosis. The resultant diagnostic tool, the TB Screen Test, is more economical and rapid (4 min) than other currently available products and can be used for the mass screening of a heavily afflicted population.  相似文献   
3.
4.
Backgroundmidwifery is a part of the nursing profession in India. This current study explores and describes the midwifery scope of practice among staff nurses.Methodsa grounded theory approach was used to develop a model. Twenty-eight service providers from the maternity sections of public health facilities, selected through purposive and theoretical sampling were interviewed in-depth. Unstructured observations in the labour wards were also used for developing the model.Findingsthe midwifery practice of staff nurses was limited in scope compared to international standards of midwifery. Their practice was circumstance driven, ranging from extended to marginal depending on the context. Their right to practice was not legally defined, but they were not specifically prohibited from practice. As a consequence, the staff nurses faced loss of skills, and deskilling when their practice was restricted. Their practice was perceived as risky, when the scope of practice was extended because it was not rightfully endorsed, the nurses having no officially recognized right to practice midwifery at that level. The clinical midwifery education of nursing and midwifery students was marginalized because the education of medical students was given priority, and the students only got exposed to the restricted practice of staff nurses.Conclusionsunclear definitions of the right to practice and the scope of practice have led to the un-utilized potential of staff nurses practising midwifery. This is detrimental because India faces an acute shortage of qualified personnel to meet the need in providing human resources for maternal health.  相似文献   
5.
6.
ABSTRACT: BACKGROUND: High maternal mortality in India is a serious public health challenge. Demand side financing interventions have emerged as a strategy to promote access to emergency obstetric care. Two such state run programs, Janani Suraksha Yojana (JSY)and Chiranjeevi Yojana (CY), were designed and implemented to reduce financial access barriers that preclude women from obtaining emergency obstetric care. JSY, a conditional cash transfer, awards money directly to a woman who delivers in a public health facility. This will be studied in Madhya Pradesh province. CY, a voucher based program, empanels private obstetricians in Gujarat province, who are reimbursed by the government to perform deliveries of socioeconomically disadvantaged women. The programs have been in operation for the last seven years.Methods/designsThe study outlined in this protocol will assess and compare the influence of the two programs on various aspects of maternal health care including trends in program uptake, institutional delivery rates, maternal and neonatal outcomes, quality of care, experiences of service providers and users, and cost effectiveness. The study will collect primary data using a combination of qualitative and quantitative methods, including facility level questionnaires, observations, a population based survey, in-depth interviews, and focus group discussions. Primary data will be collected in three districts of each province. The research will take place at three levels: the state health departments, obstetric facilities in the districts and among recently delivered mothers in the community. DISCUSSION: The protocol is a comprehensive assessment of the performance and impact of the programs and an economic analysis. It will fill existing evidence gaps in the scientific literature including access and quality to services, utilization, coverage and impact. The implementation of the protocol will also generate evidence to facilitate decision making among policy makers and program managers who currently work with or are planning similar programs in different contexts.  相似文献   
7.
BackgroundThe COVID-19 pandemic has strained the healthcare systems across the world but its impact on acute stroke care is just being elucidated. We hypothesized a major global impact of COVID-19 not only on stroke volumes but also on various aspects of thrombectomy systems.AimsWe conducted a convenience electronic survey with a 21-item questionnaire aimed to identify the changes in stroke admission volumes and thrombectomy treatment practices seen during a specified time period of the COVID-19 pandemic.MethodsThe survey was designed using Qualtrics software and sent to stroke and neuro-interventional physicians around the world who are part of the Global Executive Committee (GEC) of Mission Thrombectomy 2020, a global coalition under the aegis of Society of Vascular and Interventional Neurology, between April 5th and May 15th, 2020.ResultsThere were 113 responses to the survey across 25 countries with a response rate of 31% among the GEC members. Globally there was a median 33% decrease in stroke admissions and a 25% decrease in mechanical thrombectomy (MT) procedures during the COVID-19 pandemic period until May 15th, 2020 compared to pre-pandemic months. The intubation policy for MT procedures during the pandemic was highly variable across participating centers: 44% preferred intubating all patients, including 25% of centers that changed their policy to preferred-intubation (PI) from preferred non-intubation (PNI). On the other hand, 56% centers preferred not intubating patients undergoing MT, which included 27% centers that changed their policy from PI to PNI. There was no significant difference in rate of COVID-19 infection between PI versus PNI centers (p=0.60) or if intubation policy was changed in either direction (p=1.00). Low-volume (<10 stroke/month) compared with high-volume stroke centers (>20 strokes/month) were less likely to have neurointerventional suite specific written personal protective equipment protocols (74% vs 88%) and if present, these centers were more likely to report them to be inadequate (58% vs 92%).ConclusionOur data provides a comprehensive snapshot of the impact on acute stroke care observed worldwide during the pandemic. Overall, respondents reported decreased stroke admissions as well as decreased cases of MT with no clear preponderance in intubation policy during MT.Data access statementThe corresponding author will consider requests for sharing survey data. The study was exempt from institutional review board approval as it did not involve patient level data.  相似文献   
8.

Background and Objectives:

Thromboangiitis obliterans is a common peripheral vascular disease in India. This study was conducted to assess the efficacy of thoracoscopic dorsal sympathectomy as a treatment for Buerger disease of the upper extremities.

Methods:

Thirty thoracoscopic dorsal sympathectomies (17 left- and 13 right-sided) were performed in a tertiary medical center in 5 women and 20 men (mean age, 41 years) between July 2010 and February 2013.

Results:

The mean operative time was 30 minutes, and the mean hospital stay was 52 hours. There were no complications. All patients had improvement in pain and were relapse-free after a mean follow-up period of 11.63 months.

Discussion:

Thoracoscopic dorsal sympathectomy reduces pain significantly by reducing peripheral resistance and promoting collateral development. The increased magnification of the thoracoscopic approach permits better visualization, ensuring complete excision and therefore good results. Thoracoscopic dorsal sympathectomy for Buerger disease of the upper limb is a safe and effective treatment.  相似文献   
9.
Mammalian target of rapamycin (mTOR) plays a pivotal role in many aspects of cellular proliferation, and recent evidence suggests that an altered mTOR signaling pathway plays a central role in the pathogenesis of aging, tumor progression, neuropsychiatric, and major depressive disorder. Availability of a mTOR‐specific PET tracer will facilitate monitoring early response to treatment with mTOR inhibitors that are under clinical development. Towards this we have developed the radiosynthesis of [18F]1‐(4‐(4‐(8‐oxa‐3‐azabicyclo[3.2.1]octan‐3‐yl)‐1‐(2,2,2‐trifluoroethyl)‐1H‐pyrazolo[3,4‐d]pyrimidin‐6‐yl)phenyl)‐3‐(2‐fluoroethyl)urea [18F]ATPFU ([18F]1) as an mTOR PET ligand. Synthesis of reference 1 and the precursor for radiolabeling, 4‐(4‐8‐oxa‐3‐azabicyclo[3.2.1]‐octan‐3yl)‐1‐(2,2,2‐trifluoroethyl)‐1H‐pyrazolo[3,4‐d]pyrimidin‐6yl)aniline (10), were achieved from beta‐chloroaldehyde 3 in 4 and 5 steps, respectively, with an overall yield of 25–28%. [18F]Fluoroethylamine was prepared by heating N‐[2‐(toluene‐4‐sulfonyloxy)ethyl]phthalimide with [18F]fluoride ion in acetonitrile. [18F]1 was obtained by slow distillation under argon of [18F]FCH2CH2NH2 into amine 10 that was pre‐treated with triphosgene at 0–5 °C. The total time required for the two‐step radiosynthesis including semi‐preparative HPLC purification was 90 min, and the overall radiochemical yield of [18F]1 for the process was 15 ± 5% based on [18F]fluoride ion (decay corrected). At the end of synthesis (EOS), the specific activity was 37–74 GBq/µmol (N = 6).  相似文献   
10.
Piperine is a secondary metabolite of black pepper. Its uses in medicine were already studied. However, its derivatives have not gained considerable attention. In the presented study, the Lipoxygenase (LOX) inhibitory activity of piperine and its derivatives, piperonylic acid, piperic acid, and piperonal have been assessed and compared by enzyme kinetics, ITC and molecular modeling experiments. The presented investigations expressed that all the studied compounds inhibited LOX by binding at its active site. The IC50 values of these compounds were deduced from the kinetics data and found to be 85.79, 43.065, 45.17, and 50.78 μm for piperine, piperonylic acid, piperic acid, and piperonal, respectively. The binding free energies obtained from ITC experiments were −7.47, −8.33, −8.09, and −7.86 kcal/mol for piperine, piperonylic acid, piperic acid, and piperonal, respectively. Similarly, the glide scores obtained for piperine, piperonylic acid, piperic acid, and piperonal were −7.28, −10.32, −10.72, and −9.57 kcal/mol, respectively. The results of ITC and molecular modeling experiments suggested that piperonylic acid and piperonal exhibit stronger binding at the active site than piperine does. From the presented studies, it could be concluded that derivatives of piperine may be of higher significance than piperine for certain medicinal applications, implicating (Ayurvedic) fermented herbal drugs with piperine in them.  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