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   174篇
  免费   8篇
  国内免费   1篇
儿科学   10篇
妇产科学   3篇
基础医学   13篇
口腔科学   1篇
临床医学   8篇
内科学   32篇
皮肤病学   3篇
神经病学   4篇
特种医学   57篇
外科学   7篇
综合类   10篇
预防医学   8篇
眼科学   3篇
药学   13篇
肿瘤学   11篇
  2020年   1篇
  2018年   1篇
  2017年   1篇
  2016年   1篇
  2014年   4篇
  2013年   7篇
  2012年   1篇
  2011年   2篇
  2010年   3篇
  2009年   11篇
  2008年   6篇
  2007年   6篇
  2006年   2篇
  2005年   6篇
  2004年   2篇
  2003年   1篇
  2001年   3篇
  2000年   1篇
  1999年   3篇
  1998年   7篇
  1997年   12篇
  1996年   10篇
  1995年   12篇
  1994年   8篇
  1993年   14篇
  1992年   3篇
  1991年   1篇
  1990年   3篇
  1989年   7篇
  1988年   10篇
  1987年   10篇
  1986年   6篇
  1985年   3篇
  1983年   1篇
  1982年   2篇
  1981年   3篇
  1980年   1篇
  1979年   1篇
  1978年   2篇
  1977年   3篇
  1976年   1篇
  1970年   1篇
排序方式: 共有183条查询结果,搜索用时 15 毫秒
101.
Pui  CH; Hancock  ML; Head  DR; Rivera  GK; Look  AT; Sandlund  JT; Behm  FG 《Blood》1993,82(3):889-894
The CD34 antigen was detected on > or = 10% of the blast cells in 235 (70%) of 335 cases of newly diagnosed childhood acute lymphoblastic leukemia (ALL) treated in two consecutive chemotherapy trials. By immunophenotype, the distribution of positive cases favored early pre-B ALL (83%; n = 180) followed by pre-B ALL (61%; n = 89) and then T-cell ALL (46%; n = 61) (P < .001). Among the B-lineage cases, CD34 expression was significantly associated with favorable presenting features: age 1 to 10 years, white race, absence of central nervous system (CNS) leukemia, low serum lactate dehydrogenase level, CD10 expression, and leukemic cell hyperdiploidy (> 50 chromosomes or DNA index > or = 1.16). Event-free survival was clearly superior for patients with CD34+ leukemia (P = .01), with an estimated 83% +/- 6% (SE) of the cohort remaining free of adverse events at 5 years post diagnosis, as compared to 63% +/- 10% of the group without this feature. Multivariate analysis showed that the prognostic influence of the antigen was independent of age, leukocyte count, and other well- recognized factors, suggesting that it would add discriminatory power to current systems of risk assignment. Findings in T-cell ALL were the reverse: CD34 expression showed positive correlations with initial CNS leukemia and CD10 negativity but not with any good-risk presenting characteristics. Log-rank analysis indicated no adverse effect on treatment outcome by CD34 antigen expression, although additional patients with need to be studied to obtain a definitive answer. The opposed clinical associations of CD34 expression in B- and T-lineage ALL may reflect fundamental biologic differences between these leukemia species.  相似文献   
102.
103.
The midaortic syndrome: diagnosis and treatment   总被引:2,自引:0,他引:2  
Lewis  VD  d; Meranze  SG; McLean  GK; O'Neill  JA  Jr; Berkowitz  HD; Burke  DR 《Radiology》1988,167(1):111-113
The midaortic syndrome is an unusual entity seen in children and adolescents. It is characterized by severe narrowing of the abdominal aorta with progressive involvement of the renal and visceral branches. Eleven patients (aged 5 months to 15 years) suspected of having midaortic syndrome were examined preoperatively and postoperatively. All patients had hypertension and were examined with midstream aortography. All aortograms showed a smooth, segmental stenosis of the abdominal aorta and severe bilateral proximal renal artery stenosis. In three patients, percutaneous transluminal angioplasty of the renal artery was attempted, two preoperatively and one for a postoperative stricture. None showed long-term success, presumably due to the progressive nature of the disease. Grafts were surgically placed in ten patients and produced successful results in nine.  相似文献   
104.
Various parts of the perennial herb Hilleria latifolia (Lam.) H. Walt. (Family: Phytolaccaceae) are used in Ghanaian traditional medicine for the treatment of several inflammatory-related disorders. The present study examined the anti-inflammatory effect of an ethanolic extract of the aerial parts of Hilleria latifolia (HLE) in acute and chronic inflammation models. Since free radicals and reactive oxygen species are implicated in inflammatory diseases, the antioxidant potential of HLE was also investigated in in vitro experimental models. HLE (10–300 mg kg−1, p.o.), either preemptively or curatively, significantly inhibited carrageenan-induced foot oedema in 7-day old chicks. Similarly, the NSAID diclofenac (10–100 mg kg−1, i.p.) and the steroidal anti-inflammatory agent dexamethasone (0.3–3 mg kg−1, i.p.) dose-dependently reduced the oedema in both pre-emptive and curative treatments. In the Freund''s adjuvant induced-arthritis model in rats, HLE as well as the positive controls, dexamethasone and methotrexate, showed significant anti-arthritic properties when applied to established adjuvant arthritis. HLE (10–300 mg kg−1, p.o.) significantly reduced oedema in the ipsilateral paw of rats but failed to prevent systemic arthritic spread. The DMARD methotrexate (0.1–1 mg kg−1, i.p.) and dexamethasone (0.3–3 mg kg−1, i.p.) reduced significantly the total polyarthritic oedema as well as the spread of the arthritis from the ipsilateral to the contralateral paws of the treated animals. The extract (0.03–1.00 mg ml−1) exhibited Fe3+ reducing activity, scavenged DPPH and prevented lipid peroxidation. These findings suggest that the extract exerts in vivo anti-inflammatory activity after oral administration and also has antioxidant properties which may contribute to its activity.  相似文献   
105.

Background:

Life style related behavioural risk factors are mainly implicated for increased burden of cardio- vascular diseases. Research related to these risk behaviours especially among medical students is essential, considering their role as future physicians and role models in public health intervention programmes.

Objective:

To evaluate the burden of cardiovascular risk behaviours among students of a medical college of Delhi, India.

Materials and Methods:

A cross sectional study was carried out among undergraduate medical students of a medical college in Delhi. Self administered questionnaire was used to collect information on identification data and risk behaviours in relation to cardiovascular diseases. Binary logistic regression analysis was done to calculate adjusted odds ratio to assess association between risk behaviours and covariates.

Results:

The minimum recommendation of taking at least five servings per day of fruits and vegetables was complied only by 12% of students. Consumption of carbonated soft drinks either once or more on daily basis was present in 23.7% students and 32.0% reported frequent consumption of fast foods in past week. Consumption of alcohol was present in 28.8% students but only small proportion of students (7%) was current tobacco users. Large proportions of students (42.6%) were either not carrying out or were involved in only occasional physical activity in past week.

Conclusions:

Unhealthy behavioural practises are present and may progress as student advance through medical college. Developing strategies targeting at these risk behaviours and determining factors is necessary to promote healthy life style among medical students.  相似文献   
106.
The appearance of intraluminal signal in the cardiac chambers, the descending aorta, and blood vessels was studied in healthy subjects and patients with myocardial disease on first and second spin-echo gated magnetic resonance images. Signal was present in the cardiac chambers and the aorta at various phases of the cardiac cycle when physiological or pathological slow flow conditions are expected in healthy subjects and in patients. Healthy individuals tended to show signal in the ventricles and aorta during end-diastole, and signal was less likely to be present at higher heart rates and in systolic images. In patients with regional or global left ventricular dysfunction, intraventricular signal tended to persist into systole. Surprisingly, intraventricular signal was not present with increased frequency adjacent to infarcted regions of the myocardial wall. Thus, the mere presence of intracavitary signal cannot be used as an indicator of either regional or global cardiac contraction abnormalities. In the left atrium, signal was often present during systole. Physical factors determining the appearance of signal of flowing blood are discussed in an Appendix.  相似文献   
107.
108.
Inferior vena cava: translumbar catheterization for central venous access   总被引:3,自引:0,他引:3  
Denny  DF  Jr; Greenwood  LH; Morse  SS; Lee  GK; Baquero  J 《Radiology》1989,172(3):1013
  相似文献   
109.
110.
A 55‐year‐old man with tracheal adenocarcinoma presented with difficulty in breathing and cough with blood‐tinged expectoration. As the patient refused surgery, he was treated with definitive radiotherapy to the neck and superior mediastinum to a total dose of 50 Gy (initially 40 Gy by AP/PA portals followed by 10 Gy with a three‐field technique). He showed significant symptomatic relief to radiotherapy and defaulted from further treatment. He remained asymptomatic for 7 years, following which he developed sternal metastases and a local tumour recurrence. This case illustrates that long‐term clinical remission can be achieved by radiotherapy alone in this rare histological subtype of tracheal carcinoma.  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