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   810篇
  免费   66篇
  国内免费   9篇
耳鼻咽喉   8篇
儿科学   37篇
妇产科学   34篇
基础医学   139篇
口腔科学   7篇
临床医学   71篇
内科学   235篇
皮肤病学   16篇
神经病学   20篇
特种医学   8篇
外科学   82篇
综合类   8篇
一般理论   1篇
预防医学   38篇
眼科学   53篇
药学   67篇
中国医学   13篇
肿瘤学   48篇
  2023年   7篇
  2021年   29篇
  2020年   10篇
  2019年   31篇
  2018年   25篇
  2017年   20篇
  2016年   24篇
  2015年   32篇
  2014年   43篇
  2013年   48篇
  2012年   70篇
  2011年   78篇
  2010年   42篇
  2009年   17篇
  2008年   53篇
  2007年   63篇
  2006年   52篇
  2005年   48篇
  2004年   31篇
  2003年   33篇
  2002年   36篇
  2001年   6篇
  2000年   6篇
  1999年   4篇
  1998年   4篇
  1997年   5篇
  1996年   6篇
  1995年   2篇
  1994年   4篇
  1992年   3篇
  1991年   4篇
  1990年   7篇
  1988年   4篇
  1987年   3篇
  1986年   2篇
  1985年   3篇
  1984年   6篇
  1983年   3篇
  1982年   2篇
  1981年   2篇
  1979年   1篇
  1978年   5篇
  1977年   1篇
  1976年   4篇
  1975年   1篇
  1973年   1篇
  1972年   1篇
  1967年   1篇
  1930年   1篇
  1875年   1篇
排序方式: 共有885条查询结果,搜索用时 31 毫秒
1.
OBJECTIVE: To determine whether the use of dimenhydrinate was associated with delay in the diagnosis and management of treatable illnesses or with direct adverse effects in children with vomiting presenting to an emergency department. DESIGN: Questionnaire survey and review of drug reaction and telephone inquiry records. SETTING: The emergency department of a tertiary care children's hospital and a provincial poison information centre. PATIENTS: The parents of 148 children who presented with vomiting completed the questionnaire. The database at the poison information centre included 474 reports of adverse drug reactions over an 8-year period and 105 reports of telephone inquiries over a 4-year period. MAIN RESULTS: Twenty-one (14%) of 148 children had received dimenhydrinate before arrival at the emergency department. The patients who had received dimenhydrinate were more likely than the others to present more than 12 hours after the onset of vomiting (14 [67%] of 21 v. 43 [34%] of 127, p less than 0.01). The discharge diagnoses for those who had received dimenhydrinate included asthma, pelvic inflammatory disease and urinary tract infection. No clinically important direct adverse reactions to dimenhydrinate were documented. CONCLUSIONS: The use of dimenhydrinate in children with vomiting is associated with a risk of delay in the diagnosis of treatable medical conditions.  相似文献   
2.
3.
4.
A method is described for successfully establishing caecal amoebiasis in hamsters which were not fed and which were pretreated with 1 ml of magnesium sulphate every 24 hours for three days and then given 12 x 10(5) trophozoites of the HM-1 axenic strain or 18 x 10(5) trophozoites of the HK-9 axenic strain of Entamoeba histolytica by the oral route. All the animals developed diarrhoea within 24 hours of infection. When the animals were killed on the fifth day after infection the caecum was swollen and fused. Large macroscopic ulcers full of pus could be seen in the caecum. None of the control animals showed any of the changes mentioned above.  相似文献   
5.
The cause of the circadian variation in the incidence of acute myocardial infarction (AMI) has not been identified. Tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) have opposing effects on thrombi. Hence, the extent of the clot, the size of the infarct and outcome of patients could depend on t-PA and PAI-1 levels. In an effort to elucidate the pathophysiologic basis of circadian variation of AMI, we investigated the presence of a possible corresponding circadian variation in the levels of endogenous t-PA and PAI-1 in patients diagnosed to have AMI and the effects of hypertension, diabetes and site of the infarct on these levels. We estimated the levels of t-PA and PAI-1 in platelet-poor plasma of 42 patients with AMI on admission, using the enzyme-linked immunosorbant assay. Although not statistically significant, patients having an AMI in the morning hours had the highest t-PA:PAI-1 ratio. The normal circadian variation in PAI-1 levels was lost in patients with AMI, probably due to the disease process. Also, the t-PA levels in hypertensive patients were significantly lower than in nonhypertensives. PAI-1 levels were also significantly lower in patients with anteroseptal than in inferior and anterolateral AMI. This relationship between the fibrinolytic potential and the site of infarction needs further study. Furthermore, t-PA levels on admission were significantly lower in survivors and may have a predictive value in determining the outcome.  相似文献   
6.
Fine needle aspiration cytology plays an important role in the preoperative assessment of soft tissue neoplasms. In a 40-year-old man presenting with a large soft tissue mass in the posterior aspect of thigh a diagnosis of myxoid liposarcoma was suggested on FNAC. Scrape smears of the excised mass showed an additional finding of round cell component. Histopathology confirmed combined myxoid and round cell liposarcoma (grade 2), which behaves aggressively when compared to pure myxoid liposarcoma.  相似文献   
7.
The goal of part I of this study was to evaluate the effects of whole-body proton irradiation on lymphoid organs and specific leukocyte populations. C57BL/6 mice were exposed to the entry region of the proton Bragg curve to total doses of 0.5 gray (Gy), 1.5 Gy, and 3.0 Gy, each delivered at a low dose rate (LDR) of 1 cGy/min and high dose rate (HDR) of 80 cGy/min. Non-irradiated and 3 Gy HDR gamma-irradiated groups were included as controls. At 4 days post-irradiation, highly significant radiation dose-dependent reductions were observed in the mass of both lymphoid organs and the numbers of leukocytes and T (CD3(+)), T helper (CD3(+)/CD4(+)), T cytotoxic (CD3(+)/CD8(+)), and B (CD19(+)) cells in both blood and spleen. A less pronounced dose effect was noted for natural killer (NK1.1(+) NK) cells in spleen. Monocyte, but not granulocyte, counts in blood were highly dose-dependent. The numbers for each population generally tended to be lower with HDR than with LDR radiation; a significant dose rate effect was found in the percentages of T and B cells, monocytes, and granulocytes and in CD4(+):CD8(+) ratios. These data indicate that mononuclear cell response to the entry region of the proton Bragg curve is highly dependent upon the total dose and that dose rate effects are evident with some cell types. Results from gamma- and proton-irradiated groups (both at 3 Gy HDR) were similar, although proton-irradiation gave consistently lower values in some measurements.  相似文献   
8.
A case of nonvenereal acquisition of syphilis in a 2.5 year old male Indian child is discussed. The child had condylomata lata around the anal and prepuce, with enlarged nontender inguinal lymph nodes. Treponema pallidum was found in material from both lesions, and both the VDRL and FTA-Abs tests were positive. There were not other significant findings. The patient was treated with 1.2 million units of benzathine penicillin im, and the lesions resolved in 7 days. This boy had been raised by his grandparents since the age of 6 months. They did not report a primary syphilitic lesion, but the grandmother did admit to kissing the child's genitals, a custom of affection toward babies in the area. Sexual abuse was denied. The grandmother had a buccal lesion, which showed a Treponema on darkfield microscopy, and she had positive syphilis serology. both grandparents were also treated.  相似文献   
9.
PURPOSE: To determine the safety, maximum tolerated dose, pharmacokinetics, and toxicities associated with administration of paclitaxel poliglumex (PPX, XYOTAX, Cell Therapeutics, Inc., Bresso, Italy) given on either 3-weekly or 2-weekly schedule. EXPERIMENTAL DESIGN: Nineteen patients were investigated on the 3-weekly phase Ia study and 11 patients on the 2-weekly phase Ib study. Dose escalation starting with 100% increments and one patient per dose level was modulated in accordance with the observed toxicities. Conjugated and unconjugated paclitaxel were measured in plasma. RESULTS: Dose-limiting toxicity of neutropenia was encountered at 266 mg/m(2) (paclitaxel equivalents) in phase Ia and the maximum tolerated dose was 233 mg/m(2). Neuropathy was dose-limiting in phase Ib with a maximum tolerated dose of 177 mg/m(2). Pharmacokinetic investigations indicated a prolonged half-life of >100 hours for conjugated taxanes. Plasma concentrations of unconjugated paclitaxel were similar to those following administration of an equivalent dose of Taxol. Two partial responses were observed, one in a patient with mesothelioma at 177 mg/m(2) in phase Ia and one in a patient with gastric carcinoma at 175 mg/m(2) in phase Ib. CONCLUSION: PPX is a water-soluble paclitaxel-polymer conjugate with a prolonged half-life and limited volume of distribution. Dose-limiting toxicities were neutropenia and neuropathy. PPX showed activity in this patient population.  相似文献   
10.
Indian Journal of Pediatrics - Congenital hyperinsulinism (CHI) is a clinically and genetically heterogeneous disorder, characterized by dysregulated insulin secretion. Pathogenic variants in at...  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