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   582篇
  免费   47篇
  国内免费   6篇
耳鼻咽喉   6篇
儿科学   17篇
妇产科学   22篇
基础医学   75篇
口腔科学   18篇
临床医学   53篇
内科学   140篇
皮肤病学   17篇
神经病学   30篇
特种医学   16篇
外科学   74篇
综合类   11篇
预防医学   63篇
眼科学   6篇
药学   58篇
中国医学   3篇
肿瘤学   26篇
  2023年   9篇
  2022年   23篇
  2021年   40篇
  2020年   22篇
  2019年   40篇
  2018年   30篇
  2017年   28篇
  2016年   39篇
  2015年   35篇
  2014年   37篇
  2013年   40篇
  2012年   58篇
  2011年   43篇
  2010年   32篇
  2009年   14篇
  2008年   32篇
  2007年   33篇
  2006年   22篇
  2005年   22篇
  2004年   18篇
  2003年   12篇
  2002年   3篇
  1997年   3篇
排序方式: 共有635条查询结果,搜索用时 46 毫秒
1.
2.
Human dendritic cells (DC) comprise 2 subsets-plasmacytoid CD123(+) and myeloid CD11c(+) DC-that may have distinct roles in the regulation of immunity after allogeneic hematopoietic stem cell transplantation. In this study, we analyzed the kinetics of CD123(+) DC and CD11c(+) DC reconstitution in 31 patients who underwent transplantation with allogeneic granulocyte colony-stimulating factor-mobilized peripheral blood (PB) stem cells from HLA-identical sibling donors after myeloablative conditioning. Lineage marker-negative HLA-DR(+) CD11c(+) CD11c(+) DC and lineage marker-negative HLA-DR(+) CD123(+) CD123(+) DC, as well as monocytes and lymphoid subsets, were enumerated in donor grafts and in the PB of patients at various time points after transplantation. Reconstitution of both CD11c(+) DC and CD123(+) DC to normal levels occurred within 6 to 12 months and was not affected by the diagnosis, preparatory regimen, or graft composition. However, PB CD11c(+) DC and CD123(+) DC counts were significantly reduced in patients with acute GVHD grade II to IV (at 1 and 3 months) and grade I (at 1 month). Patients with chronic GVHD instead showed reduced CD123(+) DC counts only 6 months after transplantation. Moreover, treatment with steroids (>0.1 mg/kg) was significantly associated with reduced PB CD11c(+) DC and CD123(+) DC counts at all time points after transplantation. In multivariate analysis, only acute GVHD affected DC reconstitution early after transplantation. These results will prompt new studies addressing whether DC reconstitution correlates with immunity against infectious agents or with graft-versus-tumor reactions after PB stem cell allotransplantation.  相似文献   
3.
4.
 We have examined the effects of co-expression of Kvβ1.1 and Kvβ2.1 subunits on the gating of rat brain Kv1.4 channels, expressed in Xenopus oocytes. Expression of Kv1.4 subunits alone produced a rapidly inactivating ”A” type current, which activated at potentials beyond –60 mV in a solution containing high levels of rubidium. Current activation curves obtained from tail current measurements were fitted with a Boltzmann function, with V 1/2 = –47 mV and k = 10 mV. Neither the Kvβ1.1 nor Kvβ2.1 subunits altered the voltage dependence of activation. Both subunits accelerated the activation time constant of Kv1.4, without affecting its voltage dependence. Surprisingly, the Kvβ2.1 subunit, which lacks an N-terminal inactivation domain, was almost as effective as the Kvβ1.1 subunit in speeding up Kv1.4. Steady-state inactivation of Kv1.4 was unchanged upon co-expression with either Kvβ1.1 or Kvβ2.1 subunits. Kv1.4 recovered from inactivation with two time constants; apart from an ≈ 50% lengthening of the slow time constant with a high Kvβ2.1 injection ratio, neither time constant was altered by either the Kvβ1.1 or Kvβ2.1 subunits, suggesting little interaction with recovery from C-type inactivation. Clearly, β subunits have the potential to modify the gating of Kv1.4 channels in the brain more subtly than has been suggested previously. Received: 17 March 1997 / Accepted: 30 June 1997  相似文献   
5.
We evaluated Salmonella enterica serotype Typhi strains isolated from all body sites in Pakistan during 2013–2018. Despite an increase in overall number of localized, extensively drug-resistant Salmonella Typhi in organ infections during 2018, there was no increase in the proportion of such isolates in comparison with non–extensively drug-resistant isolates.  相似文献   
6.

Exceptional precautionary measures have been adopted to stop the transmission and control of COVID-19 through the world and Pakistan is facing lockdown in this scenario. Public loyalty to precautionary measures is affected by their knowledge, attitude, risk factors and practices (KAP) towards COVID-19. The present study was conducted among the Pakistani residents to observe the knowledge, attitude, practices and risk factors towards COVID-19 outbreak in Pakistan. A questionnaire was designed, and a cross-sectional survey was conducted among participants of the study area. Participants were asked the questions regarding knowledge, attitude, practices and risk factors towards COVID-19. Data were analyzed by SPSS and t/F test and correlation was applied among the knowledge, attitude, risk factors and practices. A total of 1060 questionnaires were received. 1004 were included while 56 were excluded. The highest representation was from Punjab province (65.6%), female (63%) and age group of 21–30 years (62.1%). Most participants were single (85%), Muslim (99.4%), Urdu speaking (45.6%) and were graduates (51.5%). Most of the participants were students (52.9%) and were from economically middle-class families (40.8%). The knowledge was positively correlated with attitude and practices whereas negatively correlated with risk factors (P?<?0.05). The attitude was negatively correlated with risk factor and positively correlated with practices. The risk factors and practices were positively correlated with each other. Health education program to improve the COVID-19 knowledge, attitude, practices and risk factors should be initiated to combat current health challenge.

  相似文献   
7.
8.
Immunocompromised populations are at great risk of the current 2020 global emergency of coronavirus disease 2019 (COVID-19), and treatment of kidney transplant recipients with COVID-19 is currently not declared. Hence, the purpose of the study is to set a clear treatment regimen. We report here a therapeutic course of 2 patients who underwent transplant surgery in March 2020 and got infected soon after. Since the transplant, these 2 patients have received triple maintenance immunosuppressive therapy with oral tacrolimus, mycophenolate mofetil (MMF), and prednisone, and they have been regularly followed up at our hospital. The tacrolimus trough level was between 10 and 12 ng/mL. After the diagnosis of COVID-19, MMF was stopped and the tacrolimus dose was reduced so that blood level was between 4 and 6 ng/mL. The first patient was a 30-year-old man who, despite being treated with hydroxychloroquine, favipiravir, oseltamivir, and azithromycin therapy, died because of the presence of other comorbidities. The second case was a 58-year-old man who fully recovered from COVID-19 pneumonia with treatment with methylprednisolone, MMF, azithromycin, favipiravir, hydroxychloroquine, and reduction in immunosuppression dosage. This reflects the importance of using glucocorticoids in the treatment of COVID-19 along with other medications and the decreased mortality rate associated with their use.  相似文献   
9.
10.
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