全文获取类型
收费全文 | 21880篇 |
免费 | 1168篇 |
国内免费 | 115篇 |
专业分类
耳鼻咽喉 | 192篇 |
儿科学 | 467篇 |
妇产科学 | 249篇 |
基础医学 | 2744篇 |
口腔科学 | 608篇 |
临床医学 | 1392篇 |
内科学 | 5261篇 |
皮肤病学 | 427篇 |
神经病学 | 1654篇 |
特种医学 | 1153篇 |
外科学 | 3874篇 |
综合类 | 95篇 |
一般理论 | 1篇 |
预防医学 | 604篇 |
眼科学 | 319篇 |
药学 | 1460篇 |
中国医学 | 86篇 |
肿瘤学 | 2577篇 |
出版年
2023年 | 114篇 |
2022年 | 284篇 |
2021年 | 522篇 |
2020年 | 272篇 |
2019年 | 379篇 |
2018年 | 471篇 |
2017年 | 412篇 |
2016年 | 511篇 |
2015年 | 520篇 |
2014年 | 676篇 |
2013年 | 770篇 |
2012年 | 1155篇 |
2011年 | 1279篇 |
2010年 | 729篇 |
2009年 | 634篇 |
2008年 | 1052篇 |
2007年 | 1169篇 |
2006年 | 1175篇 |
2005年 | 1245篇 |
2004年 | 1170篇 |
2003年 | 1132篇 |
2002年 | 1206篇 |
2001年 | 536篇 |
2000年 | 522篇 |
1999年 | 474篇 |
1998年 | 332篇 |
1997年 | 236篇 |
1996年 | 260篇 |
1995年 | 222篇 |
1994年 | 194篇 |
1993年 | 174篇 |
1992年 | 410篇 |
1991年 | 328篇 |
1990年 | 292篇 |
1989年 | 309篇 |
1988年 | 248篇 |
1987年 | 216篇 |
1986年 | 191篇 |
1985年 | 218篇 |
1984年 | 171篇 |
1983年 | 108篇 |
1982年 | 58篇 |
1979年 | 73篇 |
1977年 | 54篇 |
1975年 | 46篇 |
1974年 | 60篇 |
1973年 | 56篇 |
1971年 | 48篇 |
1969年 | 54篇 |
1968年 | 47篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Taisuke Inada Satoshi Fukushima Masayuki Murai Masatoshi Jinnin Azusa Miyashita Satoshi Nakahara Junji Yamashita Jun Aoi Shinichi Masuguchi Hironobu Ihn 《The Journal of dermatology》2015,42(2):198-201
miRNA‐221 (miR‐221) is known to be abnormally expressed in many human cancers. The serum levels of miR‐221 have been reported as a tumor marker for malignant melanoma (MM). We hypothesized that the hair shaft miR‐221 levels may be increased in patients with MM. We therefore assessed the possibility that hair shaft miR‐221 levels could be a marker for MM. The hair shaft miR‐221 levels were significantly higher in patients with MM than controls. The rates of increased hair shaft miR‐221 levels above the cut‐off value were comparable to those of serum 5‐S‐CD, which is a tumor marker commonly used for MM. Measurements of the hair shaft miR‐221 levels could have potential clinical value in the detection of MM. This is the first report investigating the hair shaft levels of an miRNA in patients with MM. Our investigations offer new insight into the relationship between miR‐221 and MM, and may provide a new, non‐invasive way to screen for melanoma. 相似文献
2.
3.
4.
Masayuki Tori Masaaki Nakahara Hiroki Akamatsu Shigeyuki Ueshima Masashi Shimizu Kazuyasu Nakao 《Journal of hepato-biliary-pancreatic sciences》2006,13(5):472-476
Even for patients with multiple pancreaticoduodenal aneurysms, successful treatment with noninvasive operative procedures can be employed, if intraoperative devices are considered. A 73‐year‐old man, without any symptoms, was admitted to our hospital and had computed tomography (CT) scanning to examine his liver for hepatitis C virus (HCV). Selective superior mesenteric artery (SMA) angiography confirmed multiple aneurysms in the anterior inferior pancreaticoduodenal artery (AIPDA), one aneurysm in the posterior inferior mesenteric artery (PIPDA), and another in the occluded celiac trunk, all with severe calcification. All of the aneurysms were thought to communicate with each other. With the celiac artery occlusion, the right hepatic artery (RHA) was revealed to be supplied by collateral arteries from the aneurysms in the AIPDA, and the left hepatic artery was shown to be supplied by collaterals from the left gastric artery. Intraoperative Doppler echography, at the time of the clamping of both IPDAs, demonstrated a marked decrease of blood velocity in all aneurysms (before clamping, >50 cm/s; after, <10 cm/s), although loss of pulsation and a marked decrease of flow in the RHA were inevitable. Therefore, each of these two IPDAs were ligated on the proximal side to the aneurysm, thus preserving the blood flow of the pancreas head fed by the PIPDA; bypass grafting from the AIPDA to the RHA, using the great saphenous vein, was done at the same time. After the creation of an anastomosis, the hepatic venous oxygen saturation (ShvO2) increased from 38% (at the time of ligation of the IPDAs) to 57% under ventilation. The patient's postoperative clinical course was uneventful. We describe and discuss our successful noninvasive operative management of multiple pancreaticoduodenal aneurysms, done while monitoring the blood flow and ShvO2, with some consideration of the literature. 相似文献
5.
6.
Masayuki Amagai 《Nihon Rinshō Men'eki Gakkai kaishi》2006,29(5):325-333
To form the human body and maintain the integrity of its complex tissues, individual cells need to hold tightly to each other. The desmosome is the major type of intercellular adhesive junction, and has desmoglein (Dsg), a cadherin type cell-cell adhesion molecule, as a transmembrane component. Dsg is now known to be targeted in autoimmune diseases, infectious diseases, as well as inherited diseases. Patients with pemphigus, an autoimmune blistering disease of the skin and mucous membrane, have IgG autoantibodies directed against Dsg1 and Dsg3. A subset of patients with pemphigus have Dsg1/Dsg4 crossreacting IgG autoantibodies. Exfoliative toxins produced by Staphylococcal aureus, which causes Staphylococcal Scalded Skin Syndrome (SSSS) and bullous impetigo, specifically digest Dsg1. A subset of patients with SSSS develop a low titer of anti-Dsg1 IgG autoantibodies. A mutation in DSG1 gene causes striate palmoplantar keratoderma and a mutation in DSG4 gene causes inherited hypotrichosis. It is not clear why so many diseases are clustered in desmogleins, but there must be a reason for this. Studies on desmogleins will provide an important framework to understand the mysteries between autoimmunity and infection. 相似文献
7.
8.
Toru Takahashi Yutaka Hasegawa Kiyohiro Ohshima Taro Nameki Yasuo Morishita 《Annals of thoracic and cardiovascular surgery》2005,11(4):245-248
Although aortic valve replacement (AVR) is an effective treatment for patients with aortic valvular disease, the implantation of a small aortic prosthesis may result in residual left ventricular outflow stenosis and transvalvular gradient. In this study, the outcome in the long-term period of patients treated with a small aortic prosthesis was analyzed retrospectively. Twenty-four patients with AVR were divided into two groups, group A and group B. Group A consisted of 16 patients with 21 mm-sized prosthetic valves, and group B consisted of 8 patients with 19 or 16 mm-sized prosthetic valves. There were no significant differences in preoperative cardiac function or operative procedure in the two groups. The mean follow-up period (months) was 55.0 in group A and 51.3 in group B. RESULTS: One patient died of cerebral infarction in group A. There were no significant differences in cardiothoracic ratio (CTR), left ventricular ejection fraction (LVEF), and left ventricular mass index (LVMI) between the two groups. Postoperative physical activity according to the New York Heart Association (NYHA) classification showed no significant differences in the two groups. Despite using a small prostheses for AVR, the postoperative course was good in the long-term period, although careful follow-up is necessary. 相似文献
9.
Y Wada H Hasegawa H Okuda K Yoshida N Yamaguchi 《The Japanese journal of psychiatry and neurology》1989,43(2):245-253
Kindling of the primary visual cortex (VC) was compared with that of the amygdala in cats. VC kindling was basically similar to kindling of the amygdala in that daily electrical stimulation can lead to the development of a generalized convulsion in most subjects, a growth of afterdischarges in their configuration and duration, and a reduction of the afterdischarge threshold. The kindling response of the VC differed from that of the amygdala in a number of respects, i.e., a high afterdischarge threshold, a different pattern of behavioral seizure development, an abrupt growth of electroclinical seizures coincident with the onset of a generalized convulsion, an intersubject variability in seizure susceptibility, and a marked seizure instability. In VC kindling the afterdischarge propagation into the amygdala was not observed until the generalized convulsion developed, and the early involvement of afterdischarge was seen in the pulvinar, lateral geniculate body, and superior colliculus. These data suggest that a neural mechanism different from amygdaloid kindling may participate in VC kindling, and that the subcortical structures of the visual system are involved in the preferential pathway for a seizure generalization from the VC. 相似文献
10.
Studies on isolated smooth muscle cells. IX. Application of papain for isolation of single smooth muscle cells from guinea-pig taenia coli 总被引:1,自引:0,他引:1
M Hasegawa M Kobayashi H Oyamada T Kamishima C Yoshida H Ohata I Maruyama K Momose Y Gomi 《Nippon Heikatsukin Gakkai zasshi》1987,23(1):35-46
To prepare single smooth muscle cells from the taenia coli of guinea pig, the application of papain to the enzymatic solution was examined under two conditions: 1) the isolation in a modified Tyrode solution (containing 0.18 mM Ca2+: 0.18 mM Ca2+-Tyrode solution) and 2) the isolation in a high-K+ Tyrode solution (Na+ was replaced by K+, and Ca2+ was not added: high-K+ Tyrode solution). The presence of papain during collagenase digestion reduced contamination of broken cells and cell debris. In the case of the high-K+ Tyrode solution, papain increased the yield of single cells significantly. The cells were contracted in a dose-dependent manner by Ca2+ in the high-K+ Tyrode solution and by carbachol in 0.18 mM Ca2+-Tyrode solution; furthermore, the contractions were antagonized by verapamil and atropine, respectively. Treatment with papain did not affect cell sensitivity to the stimulants. Therefore, our results suggest that the addition of papain is useful for the isolation of single cells to investigate the physiological and pharmacological characteristics of smooth muscle. 相似文献