全文获取类型
收费全文 | 1287篇 |
免费 | 86篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 19篇 |
妇产科学 | 28篇 |
基础医学 | 140篇 |
口腔科学 | 23篇 |
临床医学 | 63篇 |
内科学 | 230篇 |
皮肤病学 | 39篇 |
神经病学 | 128篇 |
特种医学 | 140篇 |
外科学 | 271篇 |
预防医学 | 33篇 |
眼科学 | 2篇 |
药学 | 69篇 |
中国医学 | 1篇 |
肿瘤学 | 190篇 |
出版年
2023年 | 6篇 |
2022年 | 8篇 |
2021年 | 16篇 |
2020年 | 7篇 |
2019年 | 10篇 |
2018年 | 25篇 |
2017年 | 23篇 |
2016年 | 30篇 |
2015年 | 26篇 |
2014年 | 34篇 |
2013年 | 47篇 |
2012年 | 53篇 |
2011年 | 76篇 |
2010年 | 46篇 |
2009年 | 31篇 |
2008年 | 66篇 |
2007年 | 72篇 |
2006年 | 61篇 |
2005年 | 68篇 |
2004年 | 106篇 |
2003年 | 99篇 |
2002年 | 110篇 |
2001年 | 21篇 |
2000年 | 12篇 |
1999年 | 26篇 |
1998年 | 30篇 |
1997年 | 24篇 |
1996年 | 28篇 |
1995年 | 18篇 |
1994年 | 21篇 |
1993年 | 14篇 |
1992年 | 12篇 |
1991年 | 20篇 |
1990年 | 10篇 |
1989年 | 12篇 |
1988年 | 7篇 |
1987年 | 6篇 |
1986年 | 7篇 |
1985年 | 9篇 |
1984年 | 12篇 |
1983年 | 6篇 |
1982年 | 5篇 |
1981年 | 7篇 |
1980年 | 7篇 |
1978年 | 5篇 |
1976年 | 4篇 |
1974年 | 4篇 |
1973年 | 3篇 |
1970年 | 3篇 |
1969年 | 3篇 |
排序方式: 共有1380条查询结果,搜索用时 656 毫秒
111.
Kazuhiro Samura Takato Morioka Fumiaki Yoshida Kimiaki Hashiguchi Yasushi Miyagi Masahiro Mizoguchi Tadahisa Shono Shinji Nagata Satoshi O. Suzuki Tomio Sasaki 《Child's nervous system》2008,24(5):619-622
Case report Focal cortical dysplasia (FCD) with calcification is rare. We presented a 13-year-old epileptic patient with FCD and calcification
in the left frontal lobe. At age 24, the FCD lesion and the surrounding epileptogenic cortex and underlying subcortex were
removed after chronic subdural electrode recording. Histological examination showed that the calcified lesion was not independent
of the FCD lesion but located in the subcortical area of the FCD lesion. A neoplastic nature was ruled out for the lesion.
Discussion The pathophysiological mechanism involved in the coexistence of FCD and calcification is discussed. 相似文献
112.
Chiduko Yasunaga Etsuji Suehisa Masayuki Toku Tomio Kawasaki Yoh Hidaka 《Blood coagulation & fibrinolysis》2008,19(6):597-600
We investigated the frequencies of coagulation factor deficiencies in a Japanese population. We measured factor II, V, VII and X activity in 100 healthy individuals. A specific factor deficiency was determined according to the factor activity and the ratio of the factor activity to that of other coagulation factors. Seven samples showed factor activity less than the mean -2SD of standardized factor activity (factor II: three; factor V: one; factor VII: one; factor X: one and factor V+factor VII: one). The samples with low factor II and factor VII activity were determined not to be due to deficiency because the ratios of these factor activities to other factor activities were within the range of the mean +/- 2SD. We measured activity ratios in the remaining 97 samples and identified one sample with factor V deficiency and two with factor VII deficiency. Thus, six samples with coagulation factor deficiency were identified (factor X: one; factor V: two; factor VII: two and factor V + factor VII: one). These results suggest that the Japanese population has relatively high frequencies of mild factor V, factor VII and factor X deficiencies, in which activity is reduced to approximately 50% (36-64%) of normal plasma. 相似文献
113.
The granular and dysgranular insular subregions of the cortical taste area in rats are shown to connect anatomically with the homotopical regions in the opposite hemisphere through the corpus callosum. Cells of callosal efferents and terminals of callosal fibers were found in almost all cortical layers. The findings clarify the current understanding of the morphological substrate of callosal interactions in the gustatory system. 相似文献
114.
Hiromi Ugaki Takayuki Enomoto Kazuko Fujiwara Tadashi Kimura Tomio Kawasaki 《Blood coagulation & fibrinolysis》2008,19(6):585-589
The objective of this study is to analyze the tolerance and efficacy of the subcutaneous administration of a reduced 2,500-unit low-dose unfractionated heparin given for an efficacious, yet Asian population-sensitive, prophylaxis for deep vein thrombosis and fatal pulmonary embolism. Eighty-seven Japanese patients were operated on either for abdominal or pelvic complications or both, as well as for gynecologic conditions including ovarian, cervical, and corpus cancers. Thirty-two of the patients were administered the experimental low dose of unfractionated calcium heparin for prophylaxis. The 2,500 units of low-dose unfractionated heparin were given subcutaneously 2 h preoperatively and again 12 h postoperatively. Other standard methods of mechanical prophylaxis, including graduated compression stockings and intermittent pneumatic compression, were performed. Fifty-five of the patients were not administered heparin, but did receive the same standard mechanical graduated compression stockings and intermittent pneumatic compression prophylaxis. We compared the surgical and postsurgical complications noted for low-dose unfractionated heparin patients with the results of those who received no heparin prophylaxis and analyzed this data using the Mann-Whitney U-test. There was no significant difference in the mean of the blood loss volumes. There were also no significant differences found in the perioperative bleeding complications between the two groups. However, three (3/55; 6%) of the patients in the no-heparin group suffered a symptomatic pulmonary embolism, although none were fatal. There were no pulmonary embolism onsets in the heparin prophylaxis group. We feel that we have provided evidence that several serious complications, such as perisurgical hemorrhage, deep vein thrombosis, fatal pulmonary embolism, and increased postoperative recovery times, can be prevented by prophylaxis with 2,500-unit low-dose unfractionated heparin. 相似文献
115.
Shinichi Nakamura Nobuyuki Kurobe Shigeki Kashimoto Tomio Ohue Yoshiyuki Takase Masanao Shimizu 《Antimicrobial agents and chemotherapy》1983,24(1):54-60
The pharmacokinetics of AT-2266 (1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-1,8-naphthyridine- 3-carboxylic acid) were studied in various experimental animals and compared in a number of aspects with those of norfloxacin. Both agents were administered orally. The mean peak plasma levels of AT-2266 in mice, rats, and dogs (given a single dose of 50 mg/kg for mice and rats and 25 mg/kg for dogs) were 2.39, 1.63, and 5.00 mug/ml, respectively, with elimination half-lives of 2.24, 2.81, and 5.76 h. The respective mean plasma levels of norfloxacin at similar dosages were 0.510, 0.410, and 0.700 mug/ml; elimination half-lives were 1.40, 2.35, and 6.06 h. In dogs repeatedly dosed with 25 mg of AT-2266 per kg every 12 h, the mean peak plasma levels after the third and fifth doses were about 1.4 times those after the first dose. The binding rates of AT-2266 and norfloxacin to plasma of mice, rats, and dogs and to human serum ranged from 27.6 to 40.2% and 39.8 to 44.2%, respectively. In rats receiving a single dose of 50 mg/kg, the respective mean peak levels of AT-2266 in plasma, lung, muscle, and kidney were 2.47, 4.60, 5.35, and 33.9 mug/ml or g, whereas those of norfloxacin were 0.234, 0.390, 0.272, and 2.05 mug/ml or g. AT-2266 was widely distributed in tissues of dogs and monkeys after repeated dosage. The respective 24-h recoveries of AT-2266 from urine of mice, rats, and dogs after single doses of 50, 50, and 25 mg/kg were 56.6, 40.5, and 64.1%, and recoveries of norfloxacin at these doses were 4.40, 2.91, and 5.34%. The respective 24-h recoveries of AT-2266 from bile and feces of rats given a single dose of 50 mg/kg were 2.47 and 52.7%. Bioautography of plasma and urine indicated that AT-2266 was metabolized to but a slight degree. The results indicate that AT-2266 is better than norfloxacin in oral absorption and similar to the latter in stability to metabolic inactivation. 相似文献
116.
Kazumasa Yamagishi Hiroyasu Iso Taichi Shimazu Akiko Tamakoshi Norie Sawada Keitaro Matsuo Hidemi Ito Kenji Wakai Tomio Nakayama Yuri Kitamura Junya Sado Ichiro Tsuji Yumi Sugawara Tetsuya Mizoue Manami Inoue Chisato Nagata Atsuko Sadakane Keitaro Tanaka Shizuka Sasazuki 《Clinical nutrition (Edinburgh, Scotland)》2019,38(4):1678-1683
117.
PURPOSE: The protective effect of 5-aminosalicylic acid against colon carcinogenesis was investigated.
METHODS: Eighty female F344 rats aged seven weeks received an intrarectal dose of 2 mg N-methylnitrosourea dissolved in 0.5 ml of water three times weekly for five weeks to induce colon cancer. Beginning at 6 weeks after the last dose of N-methylnitrosourea, the rats were treated with an intrarectal dose of 1 mg 5-aminosalicylic acid suspended in 0.5 ml of vehicle solution (0.3 percent water solution of methylcellulose) three times weekly for 15 weeks.
RESULTS: Colon cancer incidence and mean number of tumors per rat at the end of the 15-week treatment period were significantly lower and smaller in the 5-aminosalicylic acid–treated group (10 percent and 0.2) than in the vehicle-treated (80 percent and 1.6) and untreated (68 percent and 1.1) control groups. However, the mean numbers of tumors per tumor-bearing rat were comparable: 1.5, 2, and 1.6. No distinct differences among the groups were observed in the tumor pathology with respect to their location (within 0–10 cm proximal to the anus), shape (plaque shaped or polypoid), size (<10 mm in diameter), invasion (restricted to the mucosa or submucosa), or histologic type (differentiated adenocarcinoma).
CONCLUSION: Our results indicate that 5-aminosalicylic acid administered directly into the colonic lumen strongly suppresses the promotion stage of colon carcinogenesis. 相似文献
118.
119.
120.
Yuki Iwasawa Tomoyuki Fujii Takeshi Nagamatsu Kei Kawana Shinichi Okudaira Shiho Miura Junko Matsumoto Ayako Tomio Hironobu Hyodo Takahiro Yamashita Katsutoshi Oda Shiro Kozuma Junken Aoki Yutaka Yatomi Yuji Taketani 《American journal of reproductive immunology (New York, N.Y. : 1989)》2009,62(2):90-95
Problem Lysophosphatidic acid (LPA) is a bioactive lipid mediator and thought to play an important role in pregnancy. Plasma LPA is produced by autotaxin (ATX), and ATX activity in plasma increases during pregnancy paralleled with gestational weeks and decreases to near the non-pregnant level soon after delivery. However, the source of increased ATX during pregnancy is still uncertain. We hypothesized that the source of increased ATX might be placenta.
Method of study We investigated the protein and mRNA expression of ATX in human placenta using immunohistochemistry and RT-PCR, respectively.
Results At all 3 gestational trimesters, immunohistochemical staining for placenta tissues revealed the most marked positive staining of ATX protein in trophoblasts. Real-time PCR revealed that mRNA amounts of ATX in placenta tissues paralleled with gestational weeks, i.e. ATX level in plasma.
Conclusion These findings suggest that trophoblasts might produce ATX and its bioactive resultant substance, LPA, paralleled with gestational weeks. 相似文献
Method of study We investigated the protein and mRNA expression of ATX in human placenta using immunohistochemistry and RT-PCR, respectively.
Results At all 3 gestational trimesters, immunohistochemical staining for placenta tissues revealed the most marked positive staining of ATX protein in trophoblasts. Real-time PCR revealed that mRNA amounts of ATX in placenta tissues paralleled with gestational weeks, i.e. ATX level in plasma.
Conclusion These findings suggest that trophoblasts might produce ATX and its bioactive resultant substance, LPA, paralleled with gestational weeks. 相似文献