全文获取类型
收费全文 | 7762篇 |
免费 | 460篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 248篇 |
儿科学 | 238篇 |
妇产科学 | 316篇 |
基础医学 | 1211篇 |
口腔科学 | 157篇 |
临床医学 | 545篇 |
内科学 | 1526篇 |
皮肤病学 | 200篇 |
神经病学 | 579篇 |
特种医学 | 443篇 |
外国民族医学 | 5篇 |
外科学 | 1165篇 |
综合类 | 65篇 |
一般理论 | 1篇 |
预防医学 | 584篇 |
眼科学 | 85篇 |
药学 | 560篇 |
中国医学 | 4篇 |
肿瘤学 | 308篇 |
出版年
2021年 | 91篇 |
2020年 | 58篇 |
2019年 | 80篇 |
2018年 | 104篇 |
2017年 | 76篇 |
2016年 | 105篇 |
2015年 | 112篇 |
2014年 | 150篇 |
2013年 | 201篇 |
2012年 | 324篇 |
2011年 | 313篇 |
2010年 | 214篇 |
2009年 | 228篇 |
2008年 | 319篇 |
2007年 | 326篇 |
2006年 | 335篇 |
2005年 | 344篇 |
2004年 | 305篇 |
2003年 | 281篇 |
2002年 | 255篇 |
2001年 | 279篇 |
2000年 | 332篇 |
1999年 | 270篇 |
1998年 | 115篇 |
1997年 | 97篇 |
1996年 | 80篇 |
1995年 | 62篇 |
1993年 | 54篇 |
1992年 | 141篇 |
1991年 | 130篇 |
1990年 | 147篇 |
1989年 | 147篇 |
1988年 | 98篇 |
1987年 | 122篇 |
1986年 | 111篇 |
1985年 | 112篇 |
1984年 | 85篇 |
1983年 | 55篇 |
1979年 | 94篇 |
1978年 | 57篇 |
1977年 | 75篇 |
1976年 | 57篇 |
1975年 | 83篇 |
1974年 | 93篇 |
1973年 | 84篇 |
1972年 | 73篇 |
1971年 | 62篇 |
1969年 | 72篇 |
1968年 | 62篇 |
1967年 | 56篇 |
排序方式: 共有8240条查询结果,搜索用时 15 毫秒
21.
22.
To date microscopy and cultural isolation still remain the “gold standard” in the laboratory diagnostics of mycobacteria. Nucleic acid amplification techniques additionally enable a rapid and sensitive detection of Mycobacterium tuberculosis. However, bacterial growth is still required for species identification and susceptibility testing which should be performed from one of the first isolates of every patient and repeated after about 2 months if cultures are still positive. By means of DNA fingerprint techniques, the confirmation of transmission, of TB outbreaks, and also of laboratory cross-contamination is feasible. 相似文献
23.
G Barzen C Schubert W Richter D Calder M B?rwald H Eichst?dt R Felix 《Strahlentherapie und Onkologie》1992,168(12):732-737
We evaluated the role of thallium-201 single-photon emission-computed tomography (SPECT) in diagnosis, differential diagnosis and follow-up of 33 patients with primary brain tumors. 27 of 33 lesions were detectable by Tl-201 SPECT because only two of eight low-grade (grade 1 and 2) astrocytomas showed Tl-201 accumulation up to a tumor to nontumor ratio of 2.6. High grade (grade 3 and 4) astrocytomas showed Tl-201 accumulation in the range of 2.2 up to 13.0 and were different from low-grade astrocytomas. Noninvasive grading of astrocytomas is therefore possible, whereas differential diagnosis of oligodendrogliomas and astrocytomas or meningiomas was not possible with Tl-201. In the follow-up of six patients, we could demonstrate, that tumor progression is correlated with increasing and tumor regression with decreasing Tl-201 accumulations. This functional changing proceed morphological findings in CT. But vanishing of Tl-201 accumulation during therapy does not mean vanishing of tumor as could be demonstrated by follow-up. 相似文献
24.
The following article presents two new cases of a lipofibroma of the median nerve. This formation is a very rare benign tumor of peripheral nerve tissue. Up to now 30 cases have been reported in the literature and are reviewed in this article and are compared with the two cases reported. Besides the operative treatment, which made the neuropathological diagnosis possible, preoperative diagnosis has been extended by MNT-scans of the involved parts of the nerve. The noninfiltrating character of the tumor could be well recognized on these scans. The signal quality and the anatomical proximity to the median nerve made the diagnosis of a lipofibroma likely. By the postoperative histological reviews the diagnosis was confirmed in classic manner. The immunological marking of the S-100 protein showed a remarkable reduction of this protein in these peripheral nerve tumors. The two cases reported by us recapitulate the clinical history typically and describe symptoms and our treatment for the lipofibroma of the median nerve. 相似文献
25.
The Changing Faces of the Nutcracker Esophagus 总被引:3,自引:0,他引:3
Christine B. Dalton P.A.C. Donald O. Castell M.D. Joel E. Richter M.D. 《The American journal of gastroenterology》1988,83(6):623-628
Although the nutcracker esophagus, characterized by high amplitude peristaltic contractions with mean distal amplitude greater than 180 mm Hg, is the most common esophageal motility disorder associated with noncardiac chest pain, little is known about its natural history. Therefore, we reviewed the manometric tracings of 23 patients with the nutcracker esophagus who had an average of 4.6 studies during a mean period of 32 months. Ten age-matched volunteers with normal baseline manometry who had undergone multiple studies (mean 5.8) over a mean time span of 32 months served as controls. In the 17 nutcracker patients with three or more motility studies, the variability of mean distal amplitudes between studies was 41.9% +/- 4.1 (+/- SE) compared to 27.0% +/- 3.3 for the control subjects (p less than 0.01). Highest distal pressures were noted during the first study in 11 of 17 patients (65%) compared to two of 10 controls (20%). The consistency of the diagnosis of nutcracker esophagus varied considerably: four patients always had high amplitude pressures, three patients only had the nutcracker diagnosis on the initial study, and 10 patients intermittently had pressures in the nutcracker range. Overall, these 17 patients had the diagnosis of the nutcracker esophagus confirmed on only 54% of subsequent studies. Changes in motility patterns were intermittently seen in six of 23 patients: one diffuse spasm and five nonspecific motility disorders. None of the control subjects developed high amplitude contractions or changed their motility pattern on serial testing. The possible pathophysiological implications of the changing faces of the nutcracker esophagus are discussed. 相似文献
26.
An increasing number of patients desire body contouring surgery after massive weight loss, whether from bariatric surgery or a change in lifestyle. The fact that many body regions lose their elasticity and tissue-tension has led to stepwise treatments including abdominoplasty, thigh lift, buttocks and hip lift or liposuction. However, these procedures often do not treat the reason for the deformities. The lower body lift first described by Ted Lockwood in 1993 is a procedure that allows simultaneous skin resection and tightening of different regions including the abdomen, buttocks, hips, and thighs. In this article the authors present their 10-year experience with the body lift. Patient selection, technical details, pre- and postoperative care, complications, and expected results are all discussed. 相似文献
27.
Anna Gasinska Jan Skolyszewski Tadeusz Popiela Piotr Richter Zbigniew Darasz Krystyna Nowak Joanna Niemiec Beata Biesaga Agnieszka Adamczyk Krzysztof Bucki Krzysztof Malecki Marian Reinfuss Teresa Kowalska 《Journal of gastrointestinal surgery》2007,11(4):520-528
Purpose Assessment of tumor proliferation rate using Bromodeoxyuridine labeling index (BrdUrdLI) as a possible predictor of rectal
cancer response to preoperative radiotherapy (RT).
Methods and material Ninety-two patients were qualified either to short RT (5 Gy/fraction/5 days) and surgery about 1 week after RT (schedule I),
or to short RT and 4–5 weeks interval before surgery (schedule II). Tumor samples were taken twice from each patient: before
RT and at the time of surgery. The samples were incubated with BrdUrd for 1 h at 37°C, and the BrdUrdLI was calculated as
a percentage of BrdUrd-labeled cells.
Results Thirty-eight patients were treated according to schedule I and 54 patients according to schedule II. Mean BrdUrdLI before
RT was 8.5% and its value did not differ between the patients in the two compared groups. After RT tumors showed statistically
significant growth inhibition (reduction of BrdUrdLI). As the pretreatment BrdUrd LI was not predictive for early clinical
and pathologic tumor response, prognostic role of the ratio of BrdUrdLI after to BrdUrdLI before RT was considered. The ratios
were calculated separately for fast (BrdUrd LI > 8.5%) and slowly (BrdUrd LI ≤ 8.5%) proliferating tumors and correlated with
overall treatment time (OTT, i.e., time from the first day of RT to surgery). One month after RT, accelerated proliferation
was observed only in slowly proliferating tumors.
Conclusions Pretreatment BrdUrdLI was not predictive for early clinical and pathologic tumor response. The ratio after/before RT BrdUrdLI
was correlated to inhibition of proliferation in responsive tumors.
The paper was presented at ECCO 13, October 30 to November 03, 2005 in Paris, France 相似文献
28.
Cardiovascular risk factor profile on a population basis: Results from the Lipid Study Leipzig (LSL)
下载免费PDF全文
![点击此处可从《Experimental & Clinical Cardiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Volker Richter Fausi Rassoul Florestin Lüttge Joachim Thiery 《Experimental & Clinical Cardiology》2007,12(1):51-53
Population-based lipid screening studies were initiated in the city of Leipzig, Germany, and included more than 30,000 subjects. The objectives of the Lipid Study Leipzig (LSL) were to evaluate the cardiovascular risk factor profile and its dependence on age, nutrition and social factors. In addition, the study results were compared with those of other population-based studies, and the development of cardiovascular risk factors over a 10-year period was evaluated. LSL data were obtained from subjects recruited at community centres, work sites, schools and the University of Leipzig, Germany. Capillary blood cholesterol and high-density lipoprotein-cholesterol levels were measured using the Reflotron dry-chemistry system (Roche Diagnostics, Germany). Study data also included blood pressure, body mass index, waist-to-hip ratio, and the evaluation of dietary and lifestyle factors. The results of LSL show an age-dependent increase in cardiovascular risk, which may have been partly preventable. Furthermore, LSL showed an improvement in cardiovascular risk, with respect to plasma cholesterol, over the past 10 years in men and women older than 30 and 50 years, respectively. The known age dependence of total cholesterol and non-high-density lipoprotein-cholesterol is less pronounced for those following a healthy lifestyle and for vegetarians. This suggests that the age-dependent rise of these parameters is partly preventable. 相似文献
29.
The inactivation of adrenaline 总被引:4,自引:0,他引:4
30.
M M Ritter A C S?nnichsen W M?hrle W O Richter P Schwandt 《International journal of obesity (2005)》1991,15(6):421-427
It is speculated that endogenous opioid peptides are involved in glucose metabolism and that their homeostasis might be disturbed in obesity. Despite a different response of the pancreatic beta-cells after beta-endorphin and naloxone injections between obese patients and normal weight controls, there is little knowledge concerning the direct influence of a glucose load on beta-endorphin plasma levels, especially with respect to various nutrition states. During exploration of this topic we gained further insight on the difference of basal beta-endorphin plasma levels between normal and overweight persons. We compared beta-endorphin plasma levels during an oral glucose load in 60 obese, non-diabetic patients and in 20 normal weight controls. We also studied 40 of the obese patients after a weight reduction of 2.1 kg/m2. The following results were obtained: (1) Normal weight females have significantly lower (P less than 0.05) basal beta-endorphin levels compared to the male controls. This difference in gender is abolished in obesity where female and male patients do not differ in basal beta-endorphin plasma levels. Therefore, the difference between normal and overweight persons in beta-endorphin plasma levels was restricted to the subgroup of females. We suppose that former neglect of this difference in gender explains most of the so far reported discrepant results. (2) During the oral glucose tolerance test the beta-endorphin plasma values remained constant in the obese group. Despite improved insulin sensitivity after weight reduction there was still no change of beta-endorphin plasma levels both during the OGTT and when compared to the values before weight reduction.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献