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   7228篇
  免费   380篇
  国内免费   58篇
耳鼻咽喉   141篇
儿科学   229篇
妇产科学   85篇
基础医学   847篇
口腔科学   153篇
临床医学   431篇
内科学   2067篇
皮肤病学   92篇
神经病学   377篇
特种医学   436篇
外科学   1272篇
综合类   30篇
一般理论   1篇
预防医学   146篇
眼科学   125篇
药学   353篇
中国医学   13篇
肿瘤学   868篇
  2024年   6篇
  2023年   67篇
  2022年   163篇
  2021年   258篇
  2020年   114篇
  2019年   181篇
  2018年   216篇
  2017年   183篇
  2016年   198篇
  2015年   197篇
  2014年   257篇
  2013年   332篇
  2012年   534篇
  2011年   550篇
  2010年   287篇
  2009年   224篇
  2008年   419篇
  2007年   466篇
  2006年   455篇
  2005年   489篇
  2004年   400篇
  2003年   445篇
  2002年   423篇
  2001年   53篇
  2000年   41篇
  1999年   73篇
  1998年   96篇
  1997年   68篇
  1996年   67篇
  1995年   72篇
  1994年   49篇
  1993年   58篇
  1992年   37篇
  1991年   28篇
  1990年   16篇
  1989年   23篇
  1988年   20篇
  1987年   10篇
  1986年   6篇
  1985年   9篇
  1984年   9篇
  1983年   9篇
  1982年   6篇
  1981年   12篇
  1980年   10篇
  1979年   9篇
  1978年   3篇
  1977年   4篇
  1976年   4篇
  1974年   3篇
排序方式: 共有7666条查询结果,搜索用时 0 毫秒
81.
Of the 47 prefectures in Japan, Iwate had the fewest cases of coronavirus disease 2019 (COVID-19), with the first diagnosis officially confirmed on July 28, 2020. A baseline serological survey of COVID-19 antibodies is essential to accurately evaluate an epidemic outbreak. The primary purpose of this study was to determine pre-epidemic prevalence of COVID-19 antibodies among healthcare workers, using two laboratory-based quantitative tests. In addition, a point-of-care (POC) qualitative test, rapid, simple, and convenient for primary care clinics, was compared with the laboratory-based tests. All antibody tests were performed on serum from 1,000 healthcare workers (mean age, 40 ± 11 years) in Iwate Prefectural Central Hospital, May 29-31, 2020. A COVID-19 case was defined as showing positive results in both laboratory-based quantitative tests. None of 1,000 samples had positive results in both of the laboratory immunoassays. The POC test showed positive results in 33 of 1,000 samples (3.3%) (95% confidence interval: 2.19-4.41), but no samples were simultaneously positive in both laboratory-based tests. In conclusion, COVID-19 cases were not serologically confirmed by a baseline control study of healthcare workers at our hospital in late May, 2020. Moreover, the POC qualitative test may offer no advantage in areas with very low prevalence of COVID-19, due to higher false-positive reactions compared with laboratory-based quantitative immunoassays.  相似文献   
82.
A 54-year-old man was admitted to our hospital due to intermittent chest pain. He had a history of acute myocardial infarction, and peri-stent contrast staining had been observed at the stent implantation site. The patient previously underwent anticoagulation therapy for left ventricular thrombus and antiplatelet therapy to prevent stent thrombosis. More than one year after implantation of a drug-eluting stent, antiplatelet drugs were discontinued, and anticoagulant alone was prescribed according to the guidelines, which resulted in very late stent thrombosis. The risks of both bleeding and thrombosis must be fully considered when deciding whether or not to discontinue antiplatelet therapy during anticoagulation therapy.  相似文献   
83.
The present article, dedicated to Dr NS Dhalla on the occasion of the jubilee of his life’s work, is a brief review of articles based on the authors’ studies of sarpogrelate conducted in collaboration with Dr NS Dhalla. These studies on the effects of sarpogrelate on cardiovascular disorders have been ongoing for more than 10 years, and 10 articles have been published to date.  相似文献   
84.
85.
The aim of this study was to estimate the efficacy of contrast-enhanced ultrasound (CEUS) in detecting postpartum hemorrhage (PPH) after cesarean section. This is the first study of CEUS in obstetric hemorrhage. A total of 37 patients, operated at Nagoya University Hospital, underwent CEUS. We evaluated the findings of CEUS, which were qualitatively defined as positive when pooling or leakage of contrast agent was observed in the uterine cavity, by measuring the amount of bleeding during the first 4 h after cesarean section. The time–intensity curve patterns of leaked contrast agents were also analyzed for quantitative prediction of the amount of blood loss. Significant differences between the excessive hemorrhage (N = 7) and non-excessive hemorrhage groups (N = 30) were noted in the occurrence of positive CEUS (p = 0.011). Additionally, mean postpartum blood loss markedly increased in patients with a positive CEUS (p = 0.002). From a quantitative perspective, the time until leakage of contrast agents was detected correlated with the amount of bleeding, but the other characteristics of the time–intensity curve pattern did not provide valuable information. In conclusion, CEUS, which enables bedside assessment and rapid diagnosis, is a promising strategy for the detection of PPH.  相似文献   
86.
[Purpose] This study aimed to clarify the required number of measurements to calculate trunk muscle thickness at each position. [Participants and Methods] The participants were 30 elderly males aged >65 years. The right lumbar multifidus (L2), lumbar multifidus (L5), erector spinae, transversus abdominis, internal oblique, and external oblique muscle thicknesses were measured on longitudinal images obtained using ultrasonography in the lying, sitting, and standing positions. Two measurement values for each muscle thickness was used to calculate the intraclass correlation coefficient (1.1–1.5). [Results] The intraclass correlation coefficients of the abdominal muscle thickness measurements with “great reliabilities” were as follows: 1.3–1.5 for the external oblique muscle and 1.2–1.5 for the internal oblique and transversus abdominis muscles in the lying position; 1.3–1.5 for the external oblique and transversus abdominis muscles and 1.2–1.5 for the internal oblique muscle in the sitting position; the intraclass correlation coefficient in the standing position was 1.5 for the external oblique muscle 1.1–1.5 for the internal oblique muscle and 1.3–1.5 for the transversus abdominis muscle. In all the positions, the intraclass correlation coefficient of the measurements of the back-muscle thicknesses ranged from 1.1 to 1.5 for the right lumbar multifidus (L2), lumbar multifidus (L5), and erector spinae. [Conclusion] Depending on the posture, the abdominal muscles require multiple measurements, whereas the back muscles only require a single measurement.Key words: Intraclass correlation coefficient, Trunk muscle thicknesses, Ultrasonography  相似文献   
87.
88.
We report a case of early-phase sporadic Creutzfeldt–Jakob disease (sCJD) complicated by intracerebral hemorrhage (ICH), classified as MM1 + 2C-type based on autopsy. A 61-year-old Japanese man presented to our hospital with speaking difficulties including repeated usage of the same words. He was hospitalized on the seventh day after symptom onset, and diffusion-weighted images on magnetic resonance imaging showed hyperintense regions in the frontal cortex and caudate nucleus. On the 11th day after symptom onset, head computed tomography revealed ICH in the right occipital and parietal lobes. Routine laboratory evaluations and angiography revealed no cause of ICH. Myoclonus of the extremities and drowsiness were observed on the 15th day after symptom onset. He reached the state of akinetic mutism approximately two months after symptom onset. The cerebrospinal fluid test revealed positive real-time quaking-induced conversion and 14-3-3 protein. Electroencephalography revealed periodic sharp wave complexes. A clinical diagnosis of probable Creutzfeldt–Jakob disease was made according to the diagnostic criteria. After a relapse of pneumonia, he passed away on the 103rd day after symptom onset. Postmortem examination revealed ICH in the right posterior cingulate gyrus. No pathological change that might have caused ICH was obtained. Although the effect of sCJD on the onset of ICH is undeniable, the cause of ICH was unknown. Prion protein immunohistochemistry revealed the following results: (1) weak synaptic-type deposits in the tissue rarefacted by ICH; (2) synaptic-type deposits in the cerebral cortex, which showed fine vacuoles; and (3) perivacuolar-type deposits in the inferior temporal gyrus and lingual gyrus, which showed frequent large confluent vacuoles. Although it could be considered MM1-type sCJD clinically, this case was neuropathologically diagnosed as having MM1 + 2C-type sCJD. It was shown that ICH may occur in early-phase sCJD. To improve sCJD prognosis, treatment of complications and careful follow up are important. Furthermore, pathological diagnosis is indispensable for sCJD type diagnosis.  相似文献   
89.
We developed a questionnaire to examine the findings of cutaneous arteritis among dermatological specialists experienced in vasculitis as certified by the Committee for guidelines for the management of vasculitis and vascular disorders of the Japanese Dermatological Association. We sent a questionnaire to 12 dermatological facilities identified through the revised Committee for guidelines for the management of vasculitis and vascular disorders of the Japanese Dermatological Association. Retrospective data obtained from 84 patients at the 12 dermatological facilities between 2012 January 2016 December were evaluated. The 84 patients were categorized into two groups, a systemic steroid treatment group (group 1, n = 52) and a no systemic steroid treatment group (group 2, n = 32). C-reactive protein in group 1 patients was significantly higher than that in group 2 patients. Frequency of fever, arthritis, myalgia- and peripheral neuropathy in group 1 was significantly higher than that in group 2. We propose that these symptoms could serve as early markers for the transfer from cutaneous arteritis to systemic polyarteritis nodosa. We further suggest that patients who are subsequently associated with cerebral hemorrhage and infarction, who are originally diagnosed as having cutaneous arteritis, could progress to systemic polyarteritis nodosa. The study demonstrated that it is important for dermatologists to detect these findings early in order to establish an accurate diagnosis and a timely treatment.  相似文献   
90.
In September 2003, a double-balloon endoscope (DBE) composed of balloons attached to a scope and an overtube was released in Japan prior to becoming available in other parts of the world. The DBE was developed by Dr. Yamamoto (1), and 5 different types of scopes with different uses have already been marketed. In April 2007, a single-balloon small intestinal endoscope was released with a balloon attached only to the overtube as a subsequent model. This article presents a detailed account of the development of these scopes up to the present time.  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