全文获取类型
收费全文 | 3040篇 |
免费 | 165篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 50篇 |
妇产科学 | 16篇 |
基础医学 | 352篇 |
口腔科学 | 74篇 |
临床医学 | 217篇 |
内科学 | 953篇 |
皮肤病学 | 34篇 |
神经病学 | 350篇 |
特种医学 | 99篇 |
外科学 | 476篇 |
综合类 | 11篇 |
预防医学 | 63篇 |
眼科学 | 60篇 |
药学 | 197篇 |
中国医学 | 4篇 |
肿瘤学 | 259篇 |
出版年
2023年 | 17篇 |
2022年 | 10篇 |
2021年 | 80篇 |
2020年 | 36篇 |
2019年 | 47篇 |
2018年 | 67篇 |
2017年 | 52篇 |
2016年 | 59篇 |
2015年 | 60篇 |
2014年 | 84篇 |
2013年 | 93篇 |
2012年 | 148篇 |
2011年 | 191篇 |
2010年 | 112篇 |
2009年 | 73篇 |
2008年 | 132篇 |
2007年 | 156篇 |
2006年 | 171篇 |
2005年 | 151篇 |
2004年 | 186篇 |
2003年 | 130篇 |
2002年 | 150篇 |
2001年 | 55篇 |
2000年 | 88篇 |
1999年 | 93篇 |
1998年 | 50篇 |
1997年 | 40篇 |
1996年 | 41篇 |
1995年 | 36篇 |
1994年 | 36篇 |
1993年 | 46篇 |
1992年 | 51篇 |
1991年 | 57篇 |
1990年 | 79篇 |
1989年 | 62篇 |
1988年 | 49篇 |
1987年 | 39篇 |
1986年 | 49篇 |
1985年 | 19篇 |
1984年 | 14篇 |
1983年 | 11篇 |
1982年 | 8篇 |
1980年 | 10篇 |
1979年 | 8篇 |
1977年 | 5篇 |
1975年 | 7篇 |
1973年 | 6篇 |
1971年 | 13篇 |
1970年 | 8篇 |
1968年 | 7篇 |
排序方式: 共有3223条查询结果,搜索用时 15 毫秒
1.
H Nakane Y Okada S Sadoshima M Fujishima 《Stroke; a journal of cerebral circulation》1991,22(2):272-275
A 70-year-old woman developed left hypoglossal nerve palsy, a right hemiparesis sparing the face, and a typical left Wallenberg's syndrome. These symptoms resulted from a lesion in the left half of the medulla oblongata, suggesting Babinski-Nageotte syndrome, a rare cerebrovascular disease. This is the first case of ischemic infarction in the territory of the left vertebral artery and posterior inferior cerebellar artery demonstrated on magnetic resonance imaging. Severe bilateral lesions of the distal vertebral arteries demonstrated on digital subtraction angiography may have contributed to the development of this syndrome. 相似文献
2.
Moussa Ndong Machiko Kazami Tsukasa Suzuki Mariko Uehara Shin-ichi Katsumata Hirohumi Inoue Ken-Ichi Kobayashi Tadahiro Tadokoro Kazuharu Suzuki Yuji Yamamoto 《Nutrition Research》2009,29(9):640-647
Iron deficiency (ID) is one of the most commonly known forms of nutritional deficiencies. Low body iron is thought to induce neurologic defects but may also play a protective role against cancer development by cell growth arrest. Thus, ID may affect cellular pathways controlling cell growth and proliferation, the mechanism of which is still not fully understood. The serine/threonine protein kinase Akt and its downstream target, the mammalian Target of Rapamycin (mTOR), is known to play a crucial role in the regulation of cell growth and survival. Therefore, we hypothesized that Akt/mTOR pathway could be influenced by ID. Three-week-old male Wistar-strain rats were divided into 3 groups and the 2 groups had free access to a control diet (C group) or an iron-deficient diet (D group). The third group (PF group) were pair-fed the control diet to the mean intake of the D group. After 4 weeks, rats were killed and their brains were sampled. In separate experiments, COS-1 cells were cultured with or without the iron chelator deferoxamine. Western blots of brain samples and COS-1 lysates were used to analyze the expression and phosphorylation state of Akt, TSC2, mTOR, and S6 kinase proteins implicated in the Akt/mTOR pathway. Using 2 different ID models, we show for the first time that iron deficiency depresses Akt activity in rats and in COS-1 cells, leading to a decrease in mTOR activity. 相似文献
3.
Shoji Matsushima Yuko Sakai Yoshiki Hira Masamichi Kato Tsukasa Shigemitsu Yoichi Shiga 《Journal of pineal research》1993,14(3):145-150
Abstract: Light microscopic observations on the superficial pineal gland of Wistar-King rats were made to examine whether or not pineal volume and pinealocyte size, expressed as nuclear density, at daytime or nighttime are affected by long-term exposure to 50 Hz rotating magnetic field (MF) at 5.0 μT. Determinations of pineal volume and pinealocyte size were repeated twice (April and October) during the year. Size of pinealocytes in MF-exposed and sham-exposed rats exhibited, in addition to the difference between peripheral and central regions, regional differences in a proximodistal direction; pinealocytes in the distal and middle-peripheral regions were usually larger than those in the proximal and middle-central regions at daytime or nighttime. In October, distal and proximal pinealocytes showed significant day-night changes in size in sham-exposed rats, but not in MF-exposed animals. The situations in the two groups were almost reversed in April. Significant day-night differences were scarcely found in pinealocyte size in the middle region in the two groups. Throughout the study, pineal volume and pinealocyte size in each region were generally the same between MF-exposed and sham-exposed rats at daytime or nighttime. The results suggest that pinealocytes in the distal and proximal regions, but not those in the middle region, are affected by MF-exposure; day-night differences in sizes of distal and proximal pinealocytes appear in April and disappear in October under the influence of MF. MF may exert an effect on mechanisms controlling day-night rhythms of pinealocyte size in the rat. 相似文献
4.
AIMS: Differential diagnosis of allergic conjunctivitis or dry eye is sometimes very difficult to diagnose by symptoms and clinical examination alone, especially in older patients. It was hypothesised that clinically allergic patients who were serum antigen specific IgE negative were candidates for dry eye. METHODS: Sixty patients were studied prospectively who were clinically diagnosed with allergic conjunctivitis by their itchy sensation and papilla formation of conjunctiva. They consisted of 30 serum antigen specific IgE positive and 30 IgE negative patients, with no significant differences in age. Dry eye examination and serum total IgE were performed on these two groups. RESULTS: No significant differences were seen between the two groups with regard to age (p = 0.76) and sex ratio. The antibody negative group had lower Schirmer's test scores (p = 0.002), lower tear clearance (p = 0.0001), lower tear function index (p = 0.0001), and lower serum total IgE (p = 0.04) than the antibody positive group. CONCLUSION: This study suggests that the evaluation of serum antigen specific IgE and tear dynamics are important for the differential diagnosis of patients with allergic conjunctivitis and dry eye. Clinically diagnosed allergic conjunctivitis with negative serum antigen specific and total IgE can be one form of dry eye. 相似文献
5.
Tetsuhiko Nagao Seizo Sadoshima Takao Ishitsuka Kenji Kusuda Osamu Shiokawa Setsuro Lbayashi Masatoshi Fujishima 《Clinical and experimental pharmacology & physiology》1992,19(7):489-493
1. The effects of acute bilateral superior cervical ganglionectomy on cerebral blood flow and metabolism were investigated in stroke-prone spontaneously hypertensive rats (SHRsp), before and during cerebral ischaemia. 2. The resting cerebral blood flow was comparable between the control and denervated animals. 3. There was no significant difference in cerebral blood flow or concentration of tissue energy metabolites (adenosine triphosphate [ATP], lactate and pyruvate) between the sham-operated control and denervated animals during ischaemia. 4. The results suggest that sympathetic innervation of cerebral vessels originating from superior cervical ganglia may not play a major role in the progression of cerebral ischaemia in SHRsp. 相似文献
6.
S Kakimoto Y Yushita T Sanefuji A Kondo N Fujishima M Kishikawa K Matsumoto 《Hinyokika kiyo. Acta urologica Japonica》1986,32(5):757-763
We report a case of non-hormonal adrenocortical adenoma. The tumor was removed en block with the adrenal gland. The specimen was 5.0 X 4.5 X 3.0 cm, weighed 30 g and was solid. Histologically, this tumor had an oncocytoma-like appearance. However, as there is no concept of oncocytoma in connection with adrenocortical adenoma, this case was diagnosed as adrenocortical adenoma. A case with such histological findings has never been reported. 相似文献
7.
Minoru Yagi Takeshi Mishina Tsukasa Fujishima Kazutoshi Date Hiroshi Saito Nobuo Suzuki 《Surgery today》1997,27(1):84-87
The acute onset of peritoneal signs and shock in a 7year-old boy who had been hit in the epigastrium by a log-seesaw mandated surgical treatment. Enhanced computed tomography (CT) demonstrated complete laceration of the pancreas as well as duodenal injury, and a duodenoduodenostomy with distal pancreaticogastrostomy was subsequently performed. Temporary external drainage of the stomach and distal pancreas led to an uneventful recovery in the early postoperative period. Although the patient's postoperative development was appropriate for his age, the orifice of the distal pancreas spontaneously closed 2.5 years following surgery. We present this report to stress the fact that every effort should be made to preserve the pancreas following abdominal injury in children. 相似文献
8.
Takeshiro Fujii Yoshinori Watanabe Noritsugu Shiono Muneyasu Kawasaki Hiroki Yokomuro Tsukasa Ozawa Satoshi Hamada Hiroshi Masuhara Tetsuo Teramoto Masanori Hara Tomonori Katayanagi Yuki Sasaki Nobuya Koyama 《Annals of thoracic and cardiovascular surgery》2006,12(5):324-332
OBJECTIVE: To clarify the position of on-pump beating coronary artery bypass (CAB) and to define preoperative indicators of intentional conversion to the procedure in the era of advancement of off-pump CAB (OPCAB), we assessed on-pump beating CAB performed after the introduction of OPCAB. SUBJECTS AND METHODS: We assessed 130 patients who underwent single CAB [117 (90%) with OPCAB and 13 (10%) with on-pump beating CAB] between August 1999 (when OPCAB was selected as the first-line surgical procedure) and December 2004. RESULTS: No significant differences were seen between the groups in the number of coronary lesions or the prevalence of left main trunk (LMT) lesion. Reduced left cardiac function, cardiac dilatation, and mitral regurgitation (MR) were more remarkable in the on-pump beating CAB group. Preoperative ischemic condition was generally unstable in the both groups. A conversion to on-pump beating CAB occurred at anastomosis for the left anterior descending (LAD) branch in 61% and for the left circumflex (LCX) branch in 15%. LAD patients had more severe left cardiac dysfunction and cardiac dilatation than LCX patients. CONCLUSION: To perform safe and reliable CAB surgery, cardiovascular surgeons should define preoperative indicators of difficult OPCAB and convert OPCAB to on-pump beating CAB intentionally without hesitation when unstable hemodynamics is detected. 相似文献
9.
10.
The cecal foramen pointer was invented for a Sistrunk median cervical cyst operation. The instrument consists of three elements, namely: The cecal foramen holder, the giraffe shaped connector and the pointer needle. First of all, the cecal foramen is held by the holder which is reconstructed from hemostatic forceps. The one end of the connector is joined to the holder's handle. Then the other end of the connector comes along the patient's chin, in front of the neck. The cyst and mid-portion of the hyoid bone are dissected, followed by coring out of the thyroglossal duct toward the cecal foramen. In the coring out process, the pointer needle is pierced through the tunnel of the connector's opposite end, so that the needle top reaches to the bottom of operative wound. Then the needle shows exactly the direction to the cecal foramen and the distance from the bottom of the wound to the cecal foramen. By using this instrument the operation was successfully performed for a case of a recurrent median cervical cyst with a complete fistula to the cecal foramen. 相似文献