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   246篇
  免费   14篇
  国内免费   2篇
耳鼻咽喉   1篇
儿科学   10篇
妇产科学   5篇
基础医学   26篇
口腔科学   9篇
临床医学   28篇
内科学   89篇
皮肤病学   7篇
神经病学   15篇
特种医学   19篇
外科学   19篇
综合类   1篇
预防医学   5篇
眼科学   4篇
药学   15篇
中国医学   1篇
肿瘤学   8篇
  2023年   1篇
  2022年   12篇
  2021年   3篇
  2020年   5篇
  2019年   8篇
  2018年   11篇
  2017年   11篇
  2016年   9篇
  2015年   10篇
  2014年   20篇
  2013年   15篇
  2012年   19篇
  2011年   19篇
  2010年   14篇
  2009年   7篇
  2008年   26篇
  2007年   9篇
  2006年   16篇
  2005年   10篇
  2004年   6篇
  2003年   1篇
  2002年   5篇
  2001年   5篇
  2000年   1篇
  1999年   3篇
  1998年   1篇
  1994年   2篇
  1989年   1篇
  1987年   4篇
  1986年   1篇
  1984年   3篇
  1983年   1篇
  1982年   1篇
  1981年   2篇
排序方式: 共有262条查询结果,搜索用时 15 毫秒
11.
Sarcocystosis caused by different Sarcocystis species and is a zoonotic protozoan infection with worldwide distribution in man and many animal species. In the present study, three techniques — direct inspection, impression smears and digestion method — were used for the diagnosis of Sarcocystis infection in 112 slaughtered sheep in a Kerman abattoir from November 2010 to May 2011. A total of 450 slaughtered sheep were selected randomly during three seasons, and their oesophagus and diaphragm were inspected using naked eye examination. In the second stage, 112 carcasses out of the 450 which had no apparent infection were selected randomly and their meat investigated using two techniques: impression smear with staining and pepsin digestion. The percentage of macroscopic cysts found in the oesophagus and diaphragm muscle was 6% and 2.88%, respectively, and microscopically, infection was found in 100% of the organs. There was no significant difference between different ages or between males and females. Although all of the sheep were found to be infected with Sarcocystis, majority of the cysts were demonstrated microscopically. This suggests that meat should be cooked sufficiently, since a macroscopic inspection may not provide true results.  相似文献   
12.
Autoantibodies against CD38 (adenosine-5'-diphosphate[ADP]-ribosyl cyclase/cyclic ADP-ribose hydrolase) have been described in 10-12% of patients with type 2 diabetes. In human islets, anti-CD38 autoantibodies (CD38Abs) acutely stimulate insulin release (IR) and increase the cytosolic calcium concentration ([Ca(2+)](i)). Whether CD38Abs affect human islet cell function and survival upon prolonged in vitro exposure is not known. We cultured human islets for up to 7 days in the presence of sera from 10 patients with type 2 diabetes that had neither CD38Ab- nor [Ca(2+)](i)-mobilizing activity (-/-), sera from 6 patients with type 2 diabetes that was CD38Ab-positive and had [Ca(2+)](i)-mobilizing activity (+/+), or no sera (control). At baseline, +/+ sera caused a significant (P < 0.002) acute stimulation of IR (IR at 3.3 mmol/l glucose was 45 +/- 19, 84 +/- 24, and 34 +/- 12 micro U/ml in control, +/+, and -/- sera, respectively; the corresponding IR at 16.7 mmol/l glucose was 72 +/- 25, 204 +/- 56, and 80 +/- 32 micro U/ml). At 3 days, IR at 3.3 mmol/l glucose was 42 +/- 18, 27 +/- 11, and 43 +/- 24 micro U/ml (P = 0.0003) for control, +/+, and -/- sera, respectively, whereas at 16.7 mmol/l glucose, it was 95 +/- 76, 45 +/- 35, and 76 +/- 42 micro U/ml, respectively. After 7 days of exposure, the corresponding IR at 3.3 mmol/l glucose was 40 +/- 11, 28 +/- 12, and 35 +/- 15 micro U/ml, respectively, whereas at 16.7 mmol/l glucose it was 79 +/- 39, 39 +/- 17, and 62 +/- 39 micro U/ml. At both 3 and 7 days, IR still increased when switching from 3.3 to 16.7 mmol/l glucose (P < 0.0003), and incubation with +/+ sera induced a significant decrease in the insulin response (P < 0.002). At 7 days, the number of dead cells (as evaluated by an enzyme-linked immunosorbent assay technique) differed significantly between control (1.2 +/- 0.3 OD units) cells, islets exposed to -/- sera (1.4 +/- 0.1), and islets coincubated with +/+ sera (1.9 +/- 0.4, P < 0.01). We conclude that prolonged exposure of human islets to sera positive for the presence of CD38Abs with [Ca(2+)](i)-mobilizing activity impairs beta-cell function and viability in cultured human pancreatic islets.  相似文献   
13.
Reactive hyperemia after 1 min of arterial occlusion was studied in back, thigh and heel skin of 40 preterm and full-term neonates using laser Doppler flowmetry. Twelve infants had clinical signs of septicemia, but normal laboratory tests at the time of fluxmetry. However, CRP, leukocyte count and the ratio of immature to total neutrophils increased during the following days and septicemia was confirmed by positive blood cultures (septic group). Seven neonates with clinical signs of septicemia had developed neither positive blood cultures nor laboratory signs (non-septic group). Fifteen were healthy neonates. In the septic neonates, time to reach maximal hyperemia, maximum post-occlusive hyperemia and recovery time of skin perfusion were increased significantly in back and thigh skin and the heal skin temperature was decreased when compared to healthy neonates. Healthy and non-septic neonates showed no significant difference in any of the parameters. We conclude that altered reactive hyperemia in the skin may be an earlier sign of neonatal septicemia than laboratory tests.  相似文献   
14.
Radioiodine (131I) treatment is often applied for the treatment of Graves' disease (GD). The optimal dose of 131I for Graves' hyperthyroidism is debated. Various techniques suggest either fixed doses or varying doses based on elaborate calculations of the gland size, 131I uptake, and 131I turnover. Fixed dose regimens avoid dose calculations but there is no consensus on the actual dose to be administered. We compared two routinely recommended fixed 131I doses of 185 and 370 MBq for this purpose. Fifty nine patients with GD who had not been previously treated with 131I were randomized in two groups. Group A consisted of 33 patients who were treated with 185 MBq of 131I. Group B consisted of 26 patients who were treated with 370 MBq of 131I. Group A patients were 21% male and 78% female, mean age 38.1+/-14.4, range 15 to 77 y. Group B patients were 27% male and 73% female, mean age 40.7+/-11.7, range 27 to 72 y. All patients were reexamined every six months for two years. The following clinical outcomes were noticed: a) Persistent hyperthyroidism, which was considered as failure to treatment, requiring further 131I treatment. b) Hypothyroidism; requiring life-long replacement treatment. c) Euthyroid state. Euthyroid and hypothyroid states were considered as a response to treatment of hyperthyroidism. In Group A, 10 patients (30.3%) became euthyroid and 6 (18.2%) hypothyroid (an overall response of 48.5%), while 17 (51.5%) remained hyperthyroid by the end of the follow-up period. In Group B, 10 patients (38%) became euthyroid and 13 (50%) hypothyroid, an overall response of 88.5%. Non responders were 3 patients (11.5%). No correlation was noted between the outcome of treatment and age, sex, size of the thyroid gland or thyroid uptake in each Group of patients, while a significant correlation was noted between the disease outcome and the amount of administered 131I (P<0.003). The incidence of hypothyroidism by the end of two years of follow up was less in Group A than in Group B and the incidence of non responders to treatment was lower in Group A. In view of the higher cost of treatment, the longer time elapsing to treatment, the number of office visits by the patients and the higher number of patients with persistent hyperthyroidism in Group A, we conclude that a fixed dose of 131I of 370 MBq is more useful and effective for the treatment of GD as compared to 185 MBq of 131I.  相似文献   
15.
16.
Aim of this study was to investigate the effects of thyroxine treatment on myocardial regional left ventricular (LV) systolic and diastolic function in patients with subclinical hypothyroidism (SH) by tissue Doppler imaging (TDI). Forty-two patients (29 women and 13 men; mean age 52.2+/-15.1 years) with SH, as judged by elevated serum thyroid-stimulating hormone (TSH) levels (>3.6 mIU/l; range, 3.8-12.0) and free thyroid hormones (FT4 and FT3) within the normal range, and 30 euthyroid volunteers (21 women and nine men; mean age 50.4+/-17.1 years) underwent standard echocardiography and TDI-derived early (Em) and late (Am) diastolic velocities, systolic (Sm) velocity, and isovolumetric relaxation time (IVRTm). Patients were randomly assigned to receive or not L-thyroxine replacement therapy. All patients returned after 6 months to repeat thyroid function tests and the evaluation of all parameters. No significant differences were seen in the Sm peak between SH and control groups. Respect to controls, SH patients exhibited a lower Em, a higher Am, and, subsequently, a reduced Em/Am ratio of both lateral wall (LW) and interventricular septum (IVS) (P<0.001 for both). The IVRTm was distinctly longer in SH patients, as compared to controls (P<0.001). At 6 months, L-thyroxine-treated patients showed a significant increase of Em (P<0.01) and a subsequent increase of the Em/Am ratio (P<0.01), whereas IVRTm significantly reduced (P<0.05). No significant change in any of these parameters was observed in the untreated group. Our data suggest that SH is associated with a subtle, reversible impairment of myocardial function. TDI analysis detects and extends these functional defects by displaying alterations in regional myocardial function. L-T4 replacement therapy should be advised for these patients with the aim to correct preclinical cardiac dysfunction and prevent the development of clinically significant myocardial dysfunction.  相似文献   
17.
Febrile seizures are the most common form of childhood seizures. Although the literature associates certain micronutrients with febrile seizures, there is limited information about the effects of such micronutrients. This study aimed to determine the relationship between serum selenium level and simple febrile seizures in children. This case-control study was conducted in the Children's Hospital in Qazvin, Iran, in 2008. The serum selenium level of 30 children who experienced simple febrile seizures (case group) was measured and compared with that of 30 febrile children without seizure (control group). The serum selenium level was measured by flame atomic absorption spectrophotometer. Data were analyzed by using t-test. Mean ± standard deviation of serum selenium level in the case and control groups was 44.4 ± 10.9 and 63 ± 9.78 μg/dL, a significant difference (P < 0.001). In the case group, 18/30 patients (60%) had a serum selenium level below the norm of 46?μg/dL, whereas serum selenium level in the entire control group was within the normal range (P < 0.01). The serum selenium level in the children who had simple febrile seizures was significantly lower than in the nonseizure control group. It seems that there is an association between serum selenium deficiency and simple febrile seizures; however, further study is recommended.  相似文献   
18.
Summary. Many patients chronically infected by hepatitis C virus (HCV) experience symptoms like fatigue, dyspnea and reduced physical activity. However, in many patients, these symptoms are not proportional to the liver involvement and could resemble symptoms of chronic heart failure. To our knowledge, no study evaluated serum levels of N‐terminal pro‐brain natriuretic peptide (NT‐proBNP) in a large series of patients with HCV chronic infection (HCV+). Serum NT‐proBNP was assayed in 50 patients HCV+ and in 50 sex‐ and age‐matched controls. HCV+ patients showed significantly higher mean NT‐proBNP level than controls (P = 0.001). By defining high NT‐proBNP level as a value higher than 125 pg/mL (the single cut‐off point for patient under 75 years of age), 34% HCV+ and 6% controls had high NT‐proBNP (Fisher exact test; P < 0.001). With a cut‐off point of 300 pg/mL (used to rule out chronic heart failure in patients under 75 years of age) 10% HCV+ and 0 controls had high NT‐proBNP (Fisher exact test; P = 0.056). With a cut‐off point of 900 pg/mL (used for ruling in chronic heart failure in patients with age 50–75) 8% HCV+ patients and 0 controls had high NT‐proBNP (Fisher exact test; P = 0.12). The study demonstrates high levels of circulating NT‐proBNP in HCV+ patients compared to healthy controls. The increase of NT‐proBNP may indicate the presence of a sub‐clinical cardiac dysfunction. Further prospective studies quantifying these symptoms in correlation with echocardiography are needed to confirm this association.  相似文献   
19.
20.
PKC isoforms tau, alpha, and beta play fundamental roles in the activation of T cells and other immune cell functions. Here we show that the PKC inhibitor AEB071 both abolishes the production of several cytokines by activated human T cells, keratinocytes, and macrophages in vitro and inhibits an acute allergic contact dermatitis response in rats. To translate these findings into humans, single and multiple ascending oral doses of AEB071 were administered to healthy volunteers and patients with psoriasis, respectively. AEB071 was well tolerated with no clinically relevant laboratory abnormalities. Ex vivo stimulation of lymphocytes from subjects exposed to single doses of AEB071 resulted in a dose-dependent inhibition of both lymphocyte proliferation and IL2 mRNA expression. Clinical severity of psoriasis was reduced up to 69% compared with baseline after 2 weeks of treatment, as measured by the Psoriasis Area Severity Index (PASI) score. The improvement in psoriasis patients was accompanied by histological improvement of skin lesions and may be partially explained by a substantial reduction of p40+ dermal cells, which are known to mediate psoriasis. These data suggest that AEB071 could be an effective novel treatment regimen for psoriasis and other autoimmune diseases, and that AEB071 warrants long-term studies to establish safety and efficacy.  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