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   1909篇
  免费   99篇
  国内免费   10篇
耳鼻咽喉   28篇
儿科学   24篇
妇产科学   43篇
基础医学   231篇
口腔科学   24篇
临床医学   108篇
内科学   411篇
皮肤病学   9篇
神经病学   87篇
特种医学   58篇
外科学   356篇
综合类   10篇
预防医学   64篇
眼科学   103篇
药学   139篇
中国医学   1篇
肿瘤学   322篇
  2024年   2篇
  2023年   19篇
  2022年   28篇
  2021年   56篇
  2020年   24篇
  2019年   34篇
  2018年   69篇
  2017年   35篇
  2016年   61篇
  2015年   62篇
  2014年   68篇
  2013年   74篇
  2012年   137篇
  2011年   152篇
  2010年   89篇
  2009年   63篇
  2008年   107篇
  2007年   135篇
  2006年   154篇
  2005年   122篇
  2004年   127篇
  2003年   94篇
  2002年   88篇
  2001年   23篇
  2000年   19篇
  1999年   16篇
  1998年   23篇
  1997年   12篇
  1996年   10篇
  1995年   10篇
  1994年   9篇
  1993年   9篇
  1992年   7篇
  1991年   7篇
  1990年   10篇
  1989年   10篇
  1988年   5篇
  1987年   8篇
  1986年   5篇
  1985年   10篇
  1984年   6篇
  1983年   5篇
  1980年   1篇
  1978年   4篇
  1976年   2篇
  1975年   1篇
  1974年   1篇
  1973年   2篇
  1971年   1篇
  1967年   1篇
排序方式: 共有2018条查询结果,搜索用时 15 毫秒
81.
We report here a 76-year-old male that presented with an immediate allergy to Anisakis following saury intake. Three and a half hours after eating pressed saury sushi, whole-body pomphus appeared including itching, facial dropsical swelling, and dyspnea. Diagnostic tests revealed specific IgE antibodies against anisakis simplex and a skin prick test was positive using an extraction of anisakis simplex. The results of skin prick tests using the body and internal organs of a saury were negative. Based on these results, we diagnosed the case as immediate allergy to Anisakis. Anisakis is parasitic to a diverse array of fish, and it seems rare that eating saury will induce an allergic response because the reported parasitic rate of Anisakis on saury is only 5%. In addition, as tropomyosin is currently considered to be the primary cause of allergies to Anisakis, renewed attention should be paid to other foods for which tropomyosin is also assumed to be a common antigen.  相似文献   
82.
83.
84.
Nuclear factor κ B (NF-κB) is involved in the pathogenesis of a number of neurodegenerative disorders with neuroinflammation. In order to clarify the role of NF-κB in ALS, immunohistochemical studies with an antibody that recognizes the p65 subunit of NF-κB were performed on the spinal anterior horn of 4 patients with sporadic ALS (sALS), 1 patient with optineurin-mutated ALS (OPTN-ALS), and 3 normal controls (NC). In patients with sALS or OPTN-ALS, the expression pattern of NF-κB was altered when compared to that of NC; NF-κB immunoreactivity tended to be absent from neuronal nucleus and was increased in microglia. The down-regulation of NF-κB in neuronal nucleus might contribute to a loss of neuroprotection, or neurons with nuclear NF-κB might be lost immediately after its activation. The microglial induction of NF-κB might contribute to neuroinflammation. In conclusion, NF-κB signaling pathway could have a key role in the pathomechanism of ALS.  相似文献   
85.
86.

Objective

To investigate whether hypoxia or the female sex steroids exert direct effects on angiopoietin-1 (ANGPT1), ANGPT2, and vascular endothelial growth factor (VEGF) in human endometrial stromal cells (ESCs) to clarify the regulatory function of these local angiogenic factors in the endometrium.

Study design

Human endometrial tissues were obtained from 18 patients aged 34–47 years undergoing hysterectomy for benign reasons. ESCs were cultured under hypoxic condition or treated with 17β-estradiol (E) and/or medroxyprogesterone acetate (MPA). The mRNA levels and production of ANGPT1, ANGPT2, and VEGF were assessed by real-time RT-PCR and ELISA, respectively. Analysis of hypoxia-inducible factor 1α (HIF-1α) and estrogen receptor α (ERα) protein levels were evaluated by Western blot analysis.

Result(s)

Hypoxia reduced the mRNA expression and protein production of ANGPT-1 in ESCs, whereas those of ANGPT2 were unaffected, resulting in an increase of the ANGPT2/ANGPT1 ratio. Hypoxia induced mRNA expression and protein production of VEGF. E simultaneously induced VEGF production and suppressed ANGPT1 production, resulting in an increase of the ANGPT2/ANGPT1 ratio. MPA or E + MPA reduced ANGPT2 production and sustained the levels of ANGPT1, resulting in a decrease of the ANGPT2/ANGPT1 ratio. With regard to the interaction of E and hypoxia, E did not affect the regulation of angiogenic factors, HIF-1α, and ERα under hypoxic conditions.

Conclusions

Hypoxia and female sex hormones independently regulate the ANGPT2/ANGPT1 ratio and VEGF expression in human ESCs. These results may indicate a potential mechanism for hypoxia or female sex steroids influencing angiogenesis in the human endometrium.  相似文献   
87.
88.
89.
OBJECTIVE: A rare case of ruptured kissing aneurysms on the right internal carotid-posterior communicating artery (ICPCA) and -anterior choroidal artery (ICAchA) is reported. CASE: A 47-year-old female was transferred to our hospital because of subarachnoid hemorrhage (SAH). Cerebral angiography revealed two aneurysms on the right ICPCA and ICAchA. Right frontotemporal craniotomy was performed to obliterate them on the day of admission. Despite the presence of angiographical cleavage, these two aneurysms were attached to each other tightly, and it was extremely difficult to dissect the space between them and premature rupture occurred. A Sugita long straight clip was inserted parallel to internal carotid artery to obliterate the body of ICAchA aneurysm and the neck of ICPCA aneurysm. Another straight clip was applied to the neck of the former aneurysm. Both PCA and AchA could be secured successfully. Postoperatively, although she developed symptomatic vasospasm on the 10th day, she discharged without any neurological deficits 40 days later. CONCLUSIONS: Because of the difficulty in dissection of aneurysms, the operation for kissing aneurysms has been recognized as hazardous and challenging since Jefferson. We emphasize that a clipping technique described above should be kept in mind as a safe value, though meticulous dissection of each aneurysmal neck followed by independent neck clipping is reasonable.  相似文献   
90.
Infection is a common complication of stroke and is associated with unfavorable outcomes. Although nutritional intervention reduces the risk of postoperative infection, the impact of specific nutritional products remains unclear. From a hospital management perspective, we aimed to determine whether the provision of specific types of enteral nutrition in acute stroke patients affects infection control and hospital costs. In all, 45 acute hemorrhagic stroke patients receiving enteral nutrition in a single center (April 2017–March 2019) were retrospectively assessed. Patients were divided into two groups according to nutritional interventions: the 1.0-group with general nutrition (1.0 kcal/mL) (24 patients) and the 1.5+α-group with an initial high-protein, whey peptide-digested liquid diet (1.5 kcal/mL), followed by a highly fermentable fiber-containing liquid diet (1.5 kcal/mL initiated after 4 days) (21 patients). Changes in body mass index (BMI), duration of antibiotic use, incidence of postoperative infection, and medical cost were evaluated. Baseline patient characteristics were similar between groups. The mean BMI change was lower in the 1.5+α-group than in the 1.0-group, and the mean duration of antibiotic use throughout hospitalization was 12.8 and 18.3 days, respectively. Antibiotic use in the 1.5+α-group was lesser than that in Japanese patients from other hospitals. The incidence of postoperative infections was lower in the 1.5+α-group. Injection costs for the 1.5+α group (615 USD/patient) were lower than those for the 1.0-group. Enteral nutrition provided to acute stroke patients reduced the risk of hospital infection and medical costs.  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