全文获取类型
收费全文 | 9192篇 |
免费 | 418篇 |
国内免费 | 40篇 |
专业分类
耳鼻咽喉 | 121篇 |
儿科学 | 174篇 |
妇产科学 | 209篇 |
基础医学 | 1265篇 |
口腔科学 | 185篇 |
临床医学 | 617篇 |
内科学 | 2002篇 |
皮肤病学 | 283篇 |
神经病学 | 685篇 |
特种医学 | 350篇 |
外科学 | 1505篇 |
综合类 | 55篇 |
预防医学 | 244篇 |
眼科学 | 133篇 |
药学 | 642篇 |
中国医学 | 24篇 |
肿瘤学 | 1156篇 |
出版年
2023年 | 48篇 |
2022年 | 82篇 |
2021年 | 158篇 |
2020年 | 95篇 |
2019年 | 115篇 |
2018年 | 161篇 |
2017年 | 157篇 |
2016年 | 138篇 |
2015年 | 189篇 |
2014年 | 234篇 |
2013年 | 240篇 |
2012年 | 402篇 |
2011年 | 490篇 |
2010年 | 250篇 |
2009年 | 239篇 |
2008年 | 402篇 |
2007年 | 459篇 |
2006年 | 485篇 |
2005年 | 421篇 |
2004年 | 405篇 |
2003年 | 419篇 |
2002年 | 388篇 |
2001年 | 310篇 |
2000年 | 354篇 |
1999年 | 309篇 |
1998年 | 96篇 |
1997年 | 100篇 |
1996年 | 90篇 |
1995年 | 83篇 |
1994年 | 75篇 |
1993年 | 62篇 |
1992年 | 213篇 |
1991年 | 173篇 |
1990年 | 197篇 |
1989年 | 200篇 |
1988年 | 187篇 |
1987年 | 138篇 |
1986年 | 123篇 |
1985年 | 124篇 |
1984年 | 96篇 |
1983年 | 67篇 |
1982年 | 41篇 |
1979年 | 81篇 |
1978年 | 55篇 |
1977年 | 45篇 |
1975年 | 38篇 |
1974年 | 42篇 |
1972年 | 39篇 |
1970年 | 37篇 |
1969年 | 45篇 |
排序方式: 共有9650条查询结果,搜索用时 15 毫秒
31.
With the advent of magnetic resonance imaging (MRI), the neurohypophyseal system can be clearly delineated and its functional integrity can be predicted. The authors describe seven cases of central diabetes insipidus (DI) that occurred spontaneously. MRI revealed that the normal hyperintensity of the pituitary posterior lobe, which has been thought to be the neurosecretory material containing antidiuretic hormone, was absent in all cases. In addition, enlargement of a part of the neurohypophyseal system was recognized in five of seven cases on MRI. Three of the five patients with enlargement of a part of the neurohypophyseal tract underwent biopsy and were demonstrated to have chronic inflammation of the neurohypophyseal system. It was demonstrated that the enlarged parts of the neurohypophyseal system had shrunk either spontaneously or after the biopsy in four of the five cases. All patients are alive and have not experienced progression or remission of the disease. This study indicates that some cases of idiopathic DI result from a tiny mass lesion, usually nonneoplastic, localized in the neurohypophyseal system. 相似文献
32.
Osamu Kikuchi Hiroyuki Murai Koji Ikezoe Masakazu Kawajiri Yasumasa Ohyagi Emiko Isogai Jun-ichi Kira 《Clinical neurology》2004,44(4-5):299-302
A 58-year-old woman suffered from stiffness, swelling, rubor and muscle pain in the extremities one month after she climbed a mountain in Kyushu, an island in southern Japan. On admission, mild proximal weakness was present in the extremities. Her range of motion in the extremities was limited due to firm skin and subcutaneous stiffness which was similar to scleroderma. She showed peripheral blood eosinophilia and hypergammaglobulinemia as well as a high erythrocyte sedimentation rate. An IgM antibody against Borrelia afzelii was positive. MRI of the skeletal muscles demonstrated enhancing fascia around the biceps brachii muscle, and a biopsy specimen revealed perivascular infiltration of mononuclear cells within the hypertrophic fascia. Eosinophilic infiltration was absent. We treated the patient with prednisolone, doxycycline and amoxicillin, which alleviated the symptoms. This is the first report to show that Borrelia afzelii was involved in eosinophilic fasciitis. 相似文献
33.
34.
Yoichi Kikuchi Taku Sakurada Masato Suzuki Tomoyasu Hirano Katsuyuki Kusajima 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2004,52(8):375-378
Off-pump coronary artery bypass grafting has become an attractive surgical alternative for myocar-dial revascularization because
of the advantage of myocardial protection and other benefits of patients. However, it is still regarded as a controversial
treatment for the coronary artery disease accompanied by atrial fibrillation (AF). A significant number of patients in need
of coronary revascularization have chronic AF. Although the Cox-Maze III procedure is the gold standard for the surgical treatment
of AF, few of these patients undergo AF operations at the time of their coronary bypass grafting. We report herein a case
of the pulmonary vein isolation to eliminate the AF by means of epicardial radiofrequency ablation combined with 2 vessels
coronary artery bypass grafting on the beating heart with the aid of cardiopulmonary bypass. 相似文献
35.
Five cynomolgus monkeys treated with unilateral carotid ligation, renal hypertension, and beta-aminopropionitrile feeding were studied repeatedly by cerebral angiography to clarify the growth process of saccular cerebral aneurysms. Repeated angiography demonstrated saccular cerebral aneurysms in three of five monkeys; two aneurysms were found 15 months and a third 12 months after the operation. At autopsy, one saccular aneurysm was found to be bilocular in shape, and the others were unilocular. Fusiform aneurysms were also observed in four monkeys. Microscopic studies revealed the walls of the saccular aneurysms were very thin and consisted of fibrous tissue. In one aneurysm, the aneurysmal sac was almost obstructed by a well-organized thrombus. No evidence of intramural hemorrhage was found in any of the saccular cerebral aneurysms. The conversion of early aneurysmal changes into saccular aneurysms was found to occur abruptly, and no consistent growth rate was noted. The multiloculation of saccular aneurysms was closely related to the size of an aneurysm. The present study indicates that a saccular cerebral aneurysm may grow abruptly from one of several different kinds of early aneurysmal changes. 相似文献
36.
Effects of blood coagulation factor XIII on the development of experimental cerebral aneurysms in rats 总被引:1,自引:0,他引:1
Pathological and experimental studies have shown that cerebral aneurysms develop in part as a result of injury to the blood vessel wall. One of the peculiar aspects of aneurysm development is a defective proliferative or healing response to such injury. To examine this phenomenon, blood coagulation Factor XIII, which is known to enhance the healing process of wounds in general, was given to rats to induce experimental cerebral aneurysms. The rats were subjected to ligation of one common carotid artery and induction of hypertension, and were fed beta-aminoproprionitrile. Two weeks thereafter, Factor XIII was injected intravenously daily for 5 days (10 U/100 gm body weight/day). Twelve days after the start of Factor XIII injections, the rats were sacrificed and examined under light and electron microscopy. In seven of 12 bifurcations which developed small aneurysms, prominent intimal thickening was observed in the aneurysm lumen. In the most advanced cases, the aneurysm lumen was completely filled with proliferated smooth-muscle cells and collagen. In five of nine bifurcations that showed no aneurysm development, apparent intimal thickening was found at the site where aneurysms might be expected to grow. In the group of rats studied for induction of cerebral aneurysms but not given Factor XIII, none of 11 bifurcations with or without aneurysms showed such intimal thickening. The results indicated that the proliferative response at the sites of aneurysm development was modified by exogenous Factor XIII. 相似文献
37.
Yuichi Ando Kenji Kikuchi Naoya Ichikawa Kazuhiko Meigata Yuji Nomura Kenshi Watanabe Yoshifumi Beck Hisakazu Degawa Shinji Tomikawa Takeshi Nagao Hisanori Chida 《Surgery today》1997,27(4):353-356
We herein report the case of a 53-year-old man with a nonspecific acute colonic ulcer whose liver function deteriorated after he had undergone hepatectomy. He was referred to our hospital for a hepatoma caused by hepatitis B virus and a right hemihepatectomy was performed. His liver function was poor after the operation, and minor complications such as pleural effusion and biliary fistula developed. A large amount of melena was seen 29 days after the hepatectomy and he developed hemorrhagic shock. Superior mesenteric arteriography revealed pooling of blood in both the hepatic flexure of the ascending colon and the cecum. An emergency right hemicolectomy was performed. There was a 5 x 1-mm ulcer 18 cm distal to the ileocecal valve. Numerous erosions were observed to be scattered throughout the colonic mucosa. The patient recovered slowly and was discharged 6 months after the hepatectomy. This is the first report of an acute colonic ulcer that could have been caused by liver dysfunction. 相似文献
38.
Effects of submental stimulation for several consecutive nights in patients with obstructive sleep apnoea. 总被引:2,自引:0,他引:2 下载免费PDF全文
BACKGROUND--It has previously been reported that short term submental stimulation can reduce the frequency of apnoea and improve sleep architecture in patients with obstructive sleep apnoea. The effects of submental stimulation during consecutive nights on apnoea or on daytime sleepiness have not, however, been studied. METHODS--Patients with obstructive sleep apnoea were studied by polysomnography on a control night, for five consecutive nights of submental stimulation, and on three following nights (n = 8). A multiple sleep latency test (MSLT) (n = 8) and measurement of the upper airway resistance (n = 5) were performed during the day after the polysomnographic study, on the control night, and on the fifth stimulation night. In an additional five patients with obstructive sleep apnoea, matched for age, sex, and weight, the effects of two nights of stimulation were examined for comparison. Submental stimulation began when an apnoea lasted for five seconds and stopped with the resumption of breathing as detected by oronasal flow. RESULTS--The apnoea index, the number of times per hour that SaO2 dropped below 85% (SaO2 < 85%/hour), and the total apnoea duration expressed as a percentage of total sleep time during stimulation nights decreased to approximately 50% of the corresponding values on the control night. This improvement persisted for at least two nights after the five consecutive stimulation nights, but not after the two consecutive stimulation nights. Sleep architecture and MSLT following the stimulation nights improved but upper airway resistance did not change. CONCLUSIONS--Submental stimulation for five consecutive nights in patients with obstructive sleep apnoea improved the breathing disturbance, sleep quality, and daytime sleepiness. The effect lasted for the following two nights, but did not completely abolish the sleep disordered breathing. 相似文献
39.
Mariko Kobayashi Yukihiro Takahashi Makoto Ando Naoki Wada Masamitsu Murata Toshio Kikuchi 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(12):635-637
A 6 month-old male infant (weight: 4.5 kg) with congenital aortic stenosis underwent aortic valve replacement with a pulmonary
autograft (Ross procedure). The right ventricular outflow tract (RVOT) was reconstructed with a polytetrafluoroethylene (PTFE)-valved
equine pericardial conduit. At the age of 5, re-RVOT reconstruction with an equine pericardial patch bearing a PTFE monocusp
was required because of severe pulmonary stenosis resistant to 2 attempts of percutaneous transluminal pulmonary valvotomy.
Currently, at the age of 8, the degree of aortic regurgitation is trivial and the pulmonary autograft is free of functional
deterioration despite somatic growth. 相似文献
40.
K Mutoh T Okuno M Ito T Fujii H Mikawa K Moritake J Yamashita M Ishikawa H Kikuchi 《Journal of computer assisted tomography》1988,12(5):740-743
The CT findings of 19 children under 16 years of age with primary brain tumors in the cerebral hemisphere were investigated with special reference to the existence of cerebral hemiatrophy ipsilateral to the side of the tumor. "Ipsilateral cerebral hemiatrophy" was observed in four of 19 cases (21%). These included two cases with germinoma in the basal ganglia and two with low-grade astrocytoma in the frontal and occipital cortex. This peculiar CT finding was not specific to the location or histology of the tumor. The four cases were characterized by slow progression, which contrasted with the rapid progression of tumors shown in seven cases with a mass effect on CT. 相似文献