全文获取类型
收费全文 | 2437篇 |
免费 | 151篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 11篇 |
儿科学 | 44篇 |
妇产科学 | 21篇 |
基础医学 | 351篇 |
口腔科学 | 81篇 |
临床医学 | 134篇 |
内科学 | 725篇 |
皮肤病学 | 40篇 |
神经病学 | 152篇 |
特种医学 | 111篇 |
外科学 | 337篇 |
综合类 | 8篇 |
预防医学 | 63篇 |
眼科学 | 18篇 |
药学 | 150篇 |
中国医学 | 12篇 |
肿瘤学 | 343篇 |
出版年
2023年 | 11篇 |
2022年 | 28篇 |
2021年 | 26篇 |
2020年 | 29篇 |
2019年 | 31篇 |
2018年 | 38篇 |
2017年 | 26篇 |
2016年 | 42篇 |
2015年 | 45篇 |
2014年 | 64篇 |
2013年 | 67篇 |
2012年 | 114篇 |
2011年 | 123篇 |
2010年 | 65篇 |
2009年 | 64篇 |
2008年 | 109篇 |
2007年 | 124篇 |
2006年 | 128篇 |
2005年 | 111篇 |
2004年 | 128篇 |
2003年 | 95篇 |
2002年 | 134篇 |
2001年 | 71篇 |
2000年 | 86篇 |
1999年 | 117篇 |
1998年 | 38篇 |
1997年 | 35篇 |
1996年 | 25篇 |
1995年 | 31篇 |
1994年 | 36篇 |
1993年 | 26篇 |
1992年 | 60篇 |
1991年 | 56篇 |
1990年 | 48篇 |
1989年 | 67篇 |
1988年 | 53篇 |
1987年 | 59篇 |
1986年 | 41篇 |
1985年 | 39篇 |
1984年 | 18篇 |
1983年 | 18篇 |
1982年 | 9篇 |
1981年 | 7篇 |
1980年 | 5篇 |
1979年 | 7篇 |
1977年 | 9篇 |
1976年 | 5篇 |
1975年 | 4篇 |
1974年 | 7篇 |
1966年 | 3篇 |
排序方式: 共有2601条查询结果,搜索用时 15 毫秒
1.
Osamu Tochikubo Naoki Kura Hiroko Tokita Seiko Sakon Kiyoko Nishijima 《Hypertension research》2006,29(4):233-241
Direct measurement of intra-arterial blood pressure (BP) for 24-h provides approximately 100,000 values that vary enormously, but each (BPi) can be expressed by the equation BPi = BP0 + DeltaBPi (BP0, base BP; DeltaBPi, BP increment, i=1, 2, ..., 100 x 10(3)). About 20% of outpatients with hypertension exhibit white-coat hypertension (WCH). In such patients, DeltaBPc (i = c; c, time at the clinic) is surmised to be large. A method for explaining the physiological factors in DeltaBPc and the estimation of base BP in the outpatient clinic is important. This study addresses this issue. A total of 293 subjects were divided into four groups: 1) WCH group, 45 individuals (office BP > or = 140/90 mmHg and 24-h indirect BP < 125/80 mmHg); 2) normotensive (NT) group, 84 controls matched for age and sex; 3) WHO-I group, 95 hypertensive patients with WHO stage I (office BP > or = 140/90 mmHg and 24-h BP > or = 125/80 mmHg); and 4) WHO-II group, 69 hypertensive patients with WHO stage II. Their BPc and heart rate (HR; HRc, clinic HR) values were measured by a BP-ECG monitoring device in the outpatient clinic. Power-spectral analysis was used to obtain the ratio between the low-frequency component (LF) and high-frequency component (HF) of ECG-RR variability (LF/HF = LH). Twenty-four-hour indirect BP (and BP0) and base HR (HR0) were measured by a portable device (TM2425) at 30-min intervals. Then, DeltaBPc (= BPc - BP0) was estimated by performing linear multivariate analysis applying the model equation DeltaBPc = (BPc -alphaLH)(1-betaHR0/HRc) + epsilon to the above variables (alpha and beta, constant values; epsilon, error). This model equation made it possible to estimate BP0 (and DeltaBPc) with a high coefficient of correlation (r > or = 0.85, mean of error less than 0.82 +/- 5.9 mmHg). The predictive accuracy for discrimination between WCH and sustained hypertension (WHO-I and WHO-II groups) by this equation was 88%. The new DeltaBP-estimation device (BP-ECG monitor) enabled us to infer BP0 and is therefore useful in estimating WCH in the outpatient clinic. 相似文献
2.
3.
4.
5.
The absorption and excretion and clinical effectiveness of cefixime (CFIX) granules, a new oral cephalosporin, were studied with pediatric patients with tonsillitis and urinary tract infection (UTI). Peak serum concentrations in 3 children given orally a single dose of 3 mg/kg on fasting were 0.545 micrograms/ml at 2 hours in 1 patient, and 1.56 and 1.26 micrograms/ml at 4 hours in the other 2. The half-lives in the 3 patients were 3.21-3.42 hours, with an average of 3.29 hours. The urinary concentration during the first 6 hours was 36.5 micrograms/ml in 1 patient showing the low serum level, and the first 6-hour urinary recovery rate was 7.3%. In the other 2 patients, urinary concentrations and recovery rates up to 6 hours were 87 and 62 micrograms/ml, and 17.0 and 15.1%, respectively. The second 6-hour urinary concentrations and recovery rates were 35.5 and 20.8 micrograms/ml, and 12.7 and 8.8%, respectively. The urinary recovery rates up to 12 hours were 29.7 and 23.9%, respectively. CFIX was given orally to 19 children with 20 diseases in daily doses of 6.4-12.9 mg/kg in 2 or 3 divided portions for 3 to 12 days. Clinical evaluations were made on 18 diseases. Clinical effects of CFIX were excellent in 4, good in 7 and poor in 1 of the 12 patients with tonsillitis, and excellent in 5 and good in 1 of the 6 patients with UTI. The overall clinical effectiveness rate was 94.4%. No side effects were observed in any of the 19 patients. Hematological tests, showed slight elevation of blood platelet counts in 2 patients.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
Keisuke Morita MD ; Kazunori Urabe ; Yoichi Moroi ; Tetsuya Koga ; Ryuji Nagai ; Seiko Horiuchi ; Masutaka Furue 《Wound repair and regeneration》2005,13(1):93-101
Advanced glycation end products are the chemical modification of proteins induced by sugars in a hyperglycemic condition. Extracellular matrix proteins are prominent targets of nonenzymatic glycation because of their slow turnover rates. The aim of this study was to investigate the influence of nonenzymatic glycation of type I collagen on the migration of keratinocytes. The migration of keratinocytes was dramatically promoted on native type I collagen-coated dishes compared with that on uncoated dishes. When type I collagen was glycated with glycolaldehyde, large amounts of advanced glycation end products were produced; the glycated collagen I-coated dishes did not promote the migration of keratinocytes. Glycated collagen I did not affect the proliferative capacity of keratinocytes. However, the adhesion of keratinocytes to glycated collagen I was profoundly diminished in a glycation intensity-dependent manner. alpha2beta1 integrin is responsible for the migration and adhesion of keratinocytes to type I collagen. Pretreatment with glycated collagen I did not affect the expression level or functional activity of alpha2beta1 integrin on keratinocytes. These findings suggest that in the presence of glycated collagen I, keratinocytes lose their adhesive and migratory abilities. As the glycation did not modify the alpha2beta1 integrin on keratinocytes, it is suggested that glycation may diminish the binding capacity of type I collagen. 相似文献
7.
Y Imanishi M Kishiro O Miyazaki T Toyokawa K Kuroki H Haji T Ishikawa 《Clinical nuclear medicine》1992,17(2):114-118
Metastatic calcifications according to histopathologic and scintigraphic findings have been well-defined. The authors report a postoperative case of hyperparathyroidism with multiple metastatic calcifications in the lung, kidney, stomach, heart, and vessels that were primarily detected by bone scintigraphy and demonstrated by CT. Tc-99m MDP bone scintigraphy showed a markedly increased accumulation of radioactivity diffusely throughout the lung, left ventricular wall, both kidneys, and the gastric cardia and body. In the lung, plain films showed almost normal lung. CT, however, demonstrated patchy, slightly increased densities in the lung bilaterally. Cardiac CT indicated a considerably increased density of the ventricular myocardium and remarkable calcification in or near the atrioventricular septum or annulus fibrosus. Upper abdominal CT demonstrated increased densities diffusely throughout the gastric mucosa and renal cortex. Only vascular calcifications were depicted by plain films. Using both bone scintigraphy and CT provides accurate information about each lesion and each tissue, allowing precise diagnosis of even a questionable lesion in the early stage of metastatic calcification. Early diagnosis and early therapy offer the best chance for cure or palliative therapy. 相似文献
8.
9.
The purpose of the present study was to determine whether lymphokine activated killer (LAK) cells were involved in the development of coxsackievirus B3 (CB3) myocarditis in both the acute viremic (Experiment I) and the subacute aviremic (Experiment II) stages. To induce LAK cells, recombinant human interleukin-2 (IL-2) was administered to CB3-infected mice subcutaneously daily, starting on day 0 in Experiment I and on day 7 in Experiment II for 7 days, respectively. The treated groups were compared to infected controls. Splenic lymphocytes of IL-2 treated mice were further cultured in vitro in IL-2 containing medium for 7 days, and LAK cell activity, i.e., cytotoxic activity of the lymphocytes against EL-4 tumor cells and against cultured fetal myocytes, was assayed by51Cr-release method. In Experiment I, histologic scores, myocardial virus titers, and LAK cell activity did not differ significantly between IL-2 treated and untreated groups. In contrast, in Experiment II, there were more cellular infiltration associated with severe necrosis and higher LAK cell activity against EL-4 cells and cultured myocytes in IL-2 treated than in untreated groups. The presence of LAK cells was demonstrated in the subacute stage of murine CB3 myocarditis. Thus, the behavior of LAK cell activity may vary with the course of myocarditis, and enhanced LAK cell activity may be involved in the development of the disease.This work was supported by research grants from the Conference on Coronary Artery Disease, Japanese Education of Science and Walfare (Nos. 08877110 and 09470164), Kanae Shinyaku Foundation, and Japan Cardiovascular Research Foundation. 相似文献
10.
H M Kim S Hirota H Onoue T Hirata K Suzuki S Ohno T Kuroki Y Kitamura S Nomura 《Brain research. Developmental brain research》1992,70(2):239-244
The expression and localization of a novel protein kinase C delta (nPKC delta) mRNA were investigated using Northern blotting and in situ hybridization in the developmental process of mouse brain. In adult mice, nPKC delta was abundantly expressed in the thalamus, moderately in the pons and the cerebellum, but faintly in the cerebral cortex and the spinal cord. By in situ hybridization, the signals were observed specifically at the sensory and motor relay nuclei of the thalamus, the dorsal cochlear nuclei of the pons, and the molecular layer of the cerebellum. When developmental changes in the expression of nPKC delta gene were analyzed by in situ hybridization, it was not detectable in embryonic and neonatal brains, very weakly expressed in the thalamus in the first week, and highly expressed at two weeks of age. These results suggest that the gene expression of nPKC delta is strictly controlled by both the cell type and the developmental process. 相似文献