全文获取类型
收费全文 | 9114篇 |
免费 | 505篇 |
国内免费 | 53篇 |
专业分类
耳鼻咽喉 | 67篇 |
儿科学 | 221篇 |
妇产科学 | 70篇 |
基础医学 | 1031篇 |
口腔科学 | 149篇 |
临床医学 | 730篇 |
内科学 | 2712篇 |
皮肤病学 | 330篇 |
神经病学 | 563篇 |
特种医学 | 323篇 |
外科学 | 1498篇 |
综合类 | 31篇 |
预防医学 | 246篇 |
眼科学 | 124篇 |
药学 | 489篇 |
中国医学 | 9篇 |
肿瘤学 | 1079篇 |
出版年
2023年 | 75篇 |
2022年 | 171篇 |
2021年 | 307篇 |
2020年 | 170篇 |
2019年 | 203篇 |
2018年 | 285篇 |
2017年 | 213篇 |
2016年 | 236篇 |
2015年 | 242篇 |
2014年 | 256篇 |
2013年 | 347篇 |
2012年 | 552篇 |
2011年 | 573篇 |
2010年 | 310篇 |
2009年 | 241篇 |
2008年 | 390篇 |
2007年 | 427篇 |
2006年 | 428篇 |
2005年 | 408篇 |
2004年 | 413篇 |
2003年 | 439篇 |
2002年 | 412篇 |
2001年 | 198篇 |
2000年 | 181篇 |
1999年 | 186篇 |
1998年 | 110篇 |
1997年 | 83篇 |
1996年 | 76篇 |
1995年 | 60篇 |
1994年 | 70篇 |
1993年 | 64篇 |
1992年 | 133篇 |
1991年 | 132篇 |
1990年 | 122篇 |
1989年 | 135篇 |
1988年 | 97篇 |
1987年 | 101篇 |
1986年 | 108篇 |
1985年 | 103篇 |
1984年 | 83篇 |
1983年 | 85篇 |
1982年 | 34篇 |
1981年 | 24篇 |
1980年 | 32篇 |
1979年 | 54篇 |
1978年 | 37篇 |
1977年 | 26篇 |
1974年 | 37篇 |
1973年 | 24篇 |
1972年 | 28篇 |
排序方式: 共有9672条查询结果,搜索用时 31 毫秒
991.
The effect of tetrahydro-1 H-1,4 (5H)-dipropanol bis(3,4,5-trimethoxybenzoate)hydrochloride monohydrate (dilazep, Comelian) on puromycin-induced rat renal damage was investigated. In vivo study: Rats were divided into 3 groups, the control group; untreated, the puromycin group; puromycin (150 mg/kg) was injected intraperitoneally once, the dilazep + puromycin group; puromycin (150 mg/kg) was injected 1 h after intraperitoneal dilazep injection (2 mg/kg), and dilazep (2 mg/kg) was injected every 12 h until the end of the experiment. In each group, 84 h after puromycin injection, kidneys were isolated and renal mitochondria were prepared. The endogenous phospholipase activity in kidney homogenate was determined by high performance liquid chromatography. The activities of three segments (NADH-cytochrome c reductase, succinate-cytochrome c reductase and cytochrome c oxidase) of the electron-transport chain in mitochondria were measured enzymatically. In the puromycin group, phospholipase activity was increased and activities of all of three segments of the electron-transport chain were decreased. In the dilazep + puromycin group, premedication with dilazep prevented activation of phospholipase and maintained mitochondrial electron-transport activity. In vitro study: Mitochondria prepared from intact rat kidney were incubated with phospholipase C. Activities of the mitochondrial electron-transport chain were deteriorated by phospholipase C. These results indicated that activation of endogenous phospholipase, which digests membrane phospholipids, essential components in maintaining mitochondrial electron-transport activity, is responsible for the puromycin-induced renal damage. Premedication with dilazep prevented the damage by inhibition of the activation of phospholipase. 相似文献
992.
993.
994.
S Shindo H Matsumoto K Ogata K Kubota A Kojima T Ishimoto K Iyori M Kobayashi Y Tada 《International angiology》2002,21(3):228-232
BACKGROUND: Arterial reconstructions for ischemia in patients with Buerger's disease are technically challenging. This retrospective review was conducted to identify the critical factor for a successful outcome in bypass surgery for Buerger's disease. METHODS: Design of study: retrospective review. Setting: University hospital, hospitalized patients. Patients: since 1993, we performed 10 arterial reconstructions in 8 patients with Buerger's disease. There were 8 tibial artery bypasses and 2 collateral artery bypasses. One bypass was performed in the upper extremity. Interventions: bypass surgery with autogenous vein graft. Main outcomes measurements: graft patency. RESULTS: Over a mean follow-up period of 41.8 months, there were 3 graft occlusions. Of these, 2 were of bypasses to a patent but diseased tibial artery. One graft was occluded due to a toe stenosis which had been previously detected. The 2 collateral artery bypasses were patent at the last follow-up. CONCLUSIONS: In Buerger's disease, distal arterial reconstruction is frequently necessary to prevent ischemic limb loss. Collateral artery bypass is an option when the main arteries are affected by the disease. A patent but diseased artery should be avoided as a target for reconstruction. 相似文献
995.
We encountered a patient with acute cauda equina syndrome. The clinical course, laboratory data and imaging study, including magnetic resonance imaging (MRI) strongly suggested that this episode was caused by a vascular disorder of the conus medullaris. We emphasized the diagnostic usefulness of MRI in the vascular disease of the conus medullaris as well as the clinical importance of this disease in the differential diagnosis of acute cauda equina syndrome. 相似文献
996.
Mixed glioblastoma and sarcoma with osteoid-chondral tissue 总被引:1,自引:0,他引:1
A 56-year-old man had a right temporal lobe tumor with calcification, which was removed surgically and treated with irradiation. The histology of the tumor was mixed tumor of glioblastoma and fibrosarcoma, and in the sarcoma portion osteoid-chondral tissue was found. With stains for proteoglycan and enzyme digestion tests, hyaluronic acid and chondroitin sulfate were demonstrated in the cartilage matrix. The positive reactivity of the proteoglycans to high iron diamine staining in the first surgical specimens changed to negative in the second and autopsy specimens. It is likely that the osteoid-chondral tissue derived from metaplastic change in sarcoma cells and in the later stage pleomorphism appeared. 相似文献
997.
Mohosena Begum Tanu Yahia Mahmud Osamu Arakawa Tomohiro Takatani Hiroshi Kajihara Kentaro Kawatsu Yonekazu Hamano Manabu Asakawa Keisuke Miyazawa Tamao Noguchi 《Toxicon》2004,44(5):515-520
Tetrodotoxin (TTX) was localized as brown color in different tissues of an undescribed species of the nemertean genus Cephalothrix (phylum Nemertea) and a turbellarian Planocera reticulata (phylum Platyhelminthes) on light microscopy by means of a monoclonal anti-TTX antibody. In the Cephalothrix sp., TTX was recognized in the vesicles apically arranged in the bacillary cells in the epidermis, basal lamina, the granular cells in the proboscis epithelium, rhynchocoel epithelium, and the vesicles in the basal portion of the intestinal wall near the blood vessels and rhynchocoel. The excretory system and the ovum also showed positive reaction of TTX antigen-antibody. On the other hand, the hermaphrodite flatworm P. reticulata exhibited TTX antigen-antibody complex only in their ovum. To our knowledge, this is the first experimental effort on micro-distribution of TTX in invertebrates. 相似文献
998.
Masanori MATSUSHITA Osamu SHIROEDA Hideto INOKUCHI Makoto HIROTA Yasuki HABU Keisuke KIYOTA Kiyoshi HIRAI Takashi YOKOTA Kyoichi INOUE 《Digestive endoscopy》1994,6(3):269-274
Abstract: Gastric cancer manifesting as a submucosal tumor (SMT) is not common. A gastric barium meal and endoscopic studies performed on a 49-year-old male with epigastric pain, revealed an elevated lesion with bridging folds and central depression on the posterior wall of the lower body. An endoscopic ultrasonography (EUS) revealed a hypoechoic mass lesion within the submucosal layer. Due to an increase in the size of the tumor and its central depression during the subsequent year and a half, the patient was admitted for closer examination. Endoscopic biopsy material from the deeper layer, obtained by mucosal resection, revealed a poorly differentiated adenocarcinoma. Microscopic examination of the resected stomach showed a poorly differentiated adenocarcinoma within the submucosal layer, with considerable lymphocyte infiltration. Immunohistological examination disclosed marked T cell infiltration adjacent to the cancer cells. We suggest that considerable lymphocyte infiltration, particularly T cells, may have some role in the protective reaction against cancer cells. Our case was diagnosed as being cancer 18 months after the first endoscopic study. The biopsy material taken from the depression at the time of the first examination showed benign findings and a EUS revealed typical SMT. In the case of SMT shown by EUS to be a hypoechoic mass lesion in the submucosal layer, it is recommended that biopsy material be obtained from the deeper layer using methods available such as artificial ulcer formation. 相似文献
999.
Tomoaki Ishihara Masahiko Kaito Keisuke Takeuchi Esteban C Gabazza Yuji Tanaka Kunihiro Higuchi Jiro Ikoma Shozo Watanabe† Hiroshi Sato‡ Yukihiko Adachi 《Journal of gastroenterology and hepatology》2001,16(6):678-682
BACKGROUND AND AIM: Low-grade fasting hyperbilirubinemia is a common observation in healthy subjects (HS), whereas high-grade fasting hyperbilirubinemia is believed to be a characteristic finding of Gilbert's syndrome. This study was undertaken to assess the role of mutation in bilirubin UDP- glycosyltransferase gene (UGT1A1) on fasting hyperbilirubinemia. METHODS: Analysis of UGT1A1 and a caloric restriction test (400 kcal for 24 h) were performed in 56 healthy subjects (25 males, 31 females), and 28 patients with Gilbert's syndrome (18 males, 10 females). There were 29 healthy subjects with no mutation in UGT1A1, and 27 healthy subjects and 26 Gilbert's syndrome patients with mutations in the coding and/or promoter (TATA box) regions of UGT1A1. RESULTS: The mean increment of serum bilirubin (DeltaSB) was 7.6 micromol/L [corrected] (males) and 4.1 micromol/L (females) in subjects with no UGT1A1 mutation. Subjects with mutation in UGT1A1 showed higher levels of DeltaSB than individuals without mutation. Among healthy subjects, gender difference in DeltaSB values was observed only in individuals with the wild type of UGT1A1, but not in those with mutations in this gene. CONCLUSION: The results of the present study suggest that UGT1A1 mutation has a role in the development of high-grade fasting hyperbilirubinemia after caloric restriction. 相似文献
1000.
K Tada H Nakashima T Yoshida K Kitano 《The Journal of hand surgery, European volume》1987,12(2):273-276
Two cases of painful amputation neuroma treated by a new method are described. A vascularized island transfer from a less important finger was used, but the accompanying nerve was divided and its distal end sutured to the proximal end of the nerve in the recipient finger, after excision of the neuroma. Four years and two years later, no clinical evidence of neuroma was present at either amputation stump or donor site. 相似文献