全文获取类型
收费全文 | 52840篇 |
免费 | 2484篇 |
国内免费 | 401篇 |
专业分类
耳鼻咽喉 | 589篇 |
儿科学 | 1087篇 |
妇产科学 | 593篇 |
基础医学 | 6719篇 |
口腔科学 | 1048篇 |
临床医学 | 3128篇 |
内科学 | 13346篇 |
皮肤病学 | 1360篇 |
神经病学 | 3997篇 |
特种医学 | 2152篇 |
外科学 | 8984篇 |
综合类 | 215篇 |
一般理论 | 7篇 |
预防医学 | 1468篇 |
眼科学 | 1127篇 |
药学 | 3566篇 |
中国医学 | 181篇 |
肿瘤学 | 6158篇 |
出版年
2023年 | 294篇 |
2022年 | 600篇 |
2021年 | 1035篇 |
2020年 | 564篇 |
2019年 | 785篇 |
2018年 | 1073篇 |
2017年 | 831篇 |
2016年 | 1031篇 |
2015年 | 1107篇 |
2014年 | 1436篇 |
2013年 | 1805篇 |
2012年 | 2917篇 |
2011年 | 3253篇 |
2010年 | 1840篇 |
2009年 | 1670篇 |
2008年 | 3044篇 |
2007年 | 3268篇 |
2006年 | 3310篇 |
2005年 | 3325篇 |
2004年 | 3415篇 |
2003年 | 3432篇 |
2002年 | 3412篇 |
2001年 | 859篇 |
2000年 | 772篇 |
1999年 | 897篇 |
1998年 | 870篇 |
1997年 | 728篇 |
1996年 | 686篇 |
1995年 | 573篇 |
1994年 | 518篇 |
1993年 | 539篇 |
1992年 | 547篇 |
1991年 | 525篇 |
1990年 | 478篇 |
1989年 | 458篇 |
1988年 | 437篇 |
1987年 | 372篇 |
1986年 | 298篇 |
1985年 | 321篇 |
1984年 | 280篇 |
1983年 | 226篇 |
1982年 | 166篇 |
1981年 | 179篇 |
1980年 | 159篇 |
1979年 | 167篇 |
1978年 | 157篇 |
1977年 | 130篇 |
1976年 | 96篇 |
1975年 | 83篇 |
1974年 | 90篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
951.
952.
953.
Zenda T Masunaga T Fuwa B Okada T Ontachi Y Kondo Y Nakao S Minato H 《Journal of gastrointestinal cancer》2005,36(2):113-119
A 49-yr-old Japanese woman underwent upper gastrointestinal endoscopy because of nonspecific dyspepsia. Endoscopy revealed a flat elevated lesion about 15 mm in diameter adjacent to the duodenal papilla, the surface of which was uneven and covered with whitish granules. Based on the results of histological examination with immunohistochemistry (positive for CD10, CD20, CD79a, and bcl-2 protein, negative for CD5 and cyclin D1), a diagnosis of grade 1/3 follicular lymphoma was established. Systemic staging examinations suggested the lymphoma was restricted to the mucosa and superficial portion of the submucosa in the duodenal wall. The patient was treated with a combination of CHOP chemotherapy (cyclophosphamide, doxorubicin, vincristine, and prednisolone) and monoclonal anti-CD20 antibody (rituximab), in addition to radiotherapy. After six courses of this combination chemotherapy, complete regression of the lymphoma was observed. Although reports of small duodenal lymphoma (<20 mm or localized to the mucosa or submucosa) are extremely rare, the features of this case are characteristic of small duodenal lymphoma in terms of evolution around the ampulla of Vater, low-grade follicular type, occurrence in a women, occurrence in the fourth decade of life, and favorable outcome, and this type of tumor may need to be distinguished by pathogenesis and clinical behavior from various other gastrointestinal lymphomas. 相似文献
954.
Masaki Y Sumiyoshi M Suwa S Ohta H Matsunaga E Tamura H Takaya N Mineda Y Kojima S Nakata Y 《International heart journal》2005,46(2):323-326
Dissection of the sinus of Valsalva is an extremely rare accident during percutaneous coronary intervention (PCI), but it can lead to serious complications such as dissection of the ascending aorta. We experienced a localized dissection of the right coronary cusp without coronary artery involvement that was induced by a guiding catheter during PCI in a patient with acute myocardial infarction. The localized dissection showed pooling of the contrast medium in the acute phase, but it subsided spontaneously after 12 days without any sequelae. Manipulation of the guiding catheter should be performed with great caution not only in the coronary artery but also in the sinus of Valsalva. 相似文献
955.
Togo S Nagano Y Masui H Tanaka K Miura Y Morioka D Endo I Sekido H Ike H Shimada H 《Hepato-gastroenterology》2005,52(63):913-919
BACKGROUND/AIMS: To determine an appropriate surgical treatment for patients with multiple liver metastases, we evaluated the efficacy of two-stage hepatectomy in patients with multiple bilobular liver metastases from colorectal carcinoma. METHODOLOGY: Some patients with multiple liver metastases are not candidates for a complete resection by a single hepatectomy, even when downstaged by chemotherapy, after portal embolization. In two-stage hepatectomy, the highest possible number of tumors is resected in a first, noncurative intervention, and the remaining tumors are resected after a period of liver regeneration. Two-stage hepatectomy was performed in 11 patients. RESULTS: Two-stage hepatectomy was feasible in all of the 11 patients. In 3 of them, the first stage was a major resection (more extensive than a lobectomy). This first hepatectomy was uneventful in all patients. The second hepatectomy was also uneventful in nine patients, but in one of the other two, a perihepatic fluid infection occurred, and in the other, postoperative liver failure developed due to a right subphrenic abscess. However, all patients were discharged. The percentage of the expected resection volume at one time, calculated from CT volumetry, was 75.5+/-1.2% and the prognostic score as surgical risk was 56.6+/-4.5. In two-stage hepatectomy cases, the percentage of the resected volume and the prognostic score in the first hepatectomy were 25.4+/-6.4% and 6.7+/-7.3, and in the second, 45.7+/-4.5% and 28.5+/-5.8. During the follow-up procedures, a residual hepatic recurrence was observed in 6 patients, and pulmonary recurrence in 9. The 1- and 3-year survival rates after the first hepatectomy were 90% and 45%, with median survivals of 18 months from the first hepatectomy. CONCLUSIONS: Two-stage hepatectomy is a surgical modality intended for patients with initial unresectable metastases. However, following such surgery, protective treatment against residual liver recurrence and lung metastasis will be a most important issue. 相似文献
956.
Kazuhiko Sasai Rikuo Tanaka Mitsutoshi Kawamura Kazumitsu Honjo Naofumi Matsunaga Taishi Nakada Kiichi Homma Hiroshi Fujimura 《Journal of gastroenterology》1996,31(4):505-511
The requirement for well spread out chromosomes for the cytogenetic analysis of primary gastrointestinal tumors led us to
develop new techniques. These techniques involved two main procedures: (1) preliminary incubation with culture medium in the
presence of collagenase, Dispase, and colcemid, for 3h, and (2) treatment with an extremely hypotonic solution (0.044 M KCl)
for 30 min. The techniques were applied to 11 gastrointestinal malignancies (including 1 early gastric cancer and 1 metastatic
liver lesion of colon cancer) and significant increases (P<0.01) in the number of metaphases of analyzable karyotypes were obtained, compared with a previous method in which the standard
hypotonic molarity of KCL (0.075 M) was employed. The mean value for metaphase numbers of the analyzable karyotypes was 37.0±3.7%
in the 5 gastric cancers and 44.7±4.8% in the 5 colon cancers and 1 metastatic lesion. These values were three times and more
than twice, respectively, the values obtained by the previous method. A fluorescence in situ hybridization (FISH) study was
carried out on one cologenic tumor, the α-satellite centromere-specific probe 17 being used. Deletion of the long arm of chromosome
17 was demonstrated. The method proposed here could yield a sufficient number of metaphases without the use of tissue culture
that might cause alteration of karyotype. It can be employed with small biopsy specimens and in studies utilizing the FISH
technique. 相似文献
957.
Alterations of plasma ghrelin levels in rats with lipopolysaccharide-induced wasting syndrome and effects of ghrelin treatment on the syndrome 总被引:5,自引:0,他引:5
Hataya Y Akamizu T Hosoda H Kanamoto N Moriyama K Kangawa K Takaya K Nakao K 《Endocrinology》2003,144(12):5365-5371
Ghrelin not only strongly stimulates GH secretion, but is also involved in energy homeostasis by stimulating food intake and promoting adiposity through a GH-independent mechanism. These effects of ghrelin may play an important role in the pathophysiology of inflammatory wasting syndrome, in which both the somatotropic axis and energy balance are altered. In this study we investigated plasma ghrelin concentrations after lipopolysaccharide (LPS) administration to rats, a model of the wasting syndrome and critical illness. In addition, the therapeutic potential of the antiwasting effects of ghrelin was explored using LPS-injected rats. A single LPS injection suppressed plasma ghrelin levels 6 and 12 h later. Maximal reduction was observed 12 h after LPS injection, in a dose-dependent manner. In contrast, plasma ghrelin levels were elevated after repeated LPS injections on d 2 and 5. Peripheral administration of ghrelin twice daily (10 nmol/rat) for 5 d increased body weight gain in repeated LPS-injected rats. Furthermore, both adipose tissue weight and plasma leptin concentrations were increased after ghrelin administration in these rats. In conclusion, plasma ghrelin levels are altered in LPS-injected rats, and ghrelin treatment may provide a new therapeutic approach to the wasting syndrome and critical illness. 相似文献
958.
Kurisu S Ozono R Oshima T Kambe M Ishida T Sugino H Matsuura H Chayama K Teranishi Y Iba O Amano K Matsubara H 《Hypertension》2003,41(1):99-107
We have previously demonstrated that stimulation of the angiotensin (Ang) II type 2 receptor in vascular smooth muscle cells caused bradykinin production by activating kininogenase in transgenic mice. The aim of this study was to determine whether overexpression of AT2 receptors in cardiomyocytes attenuates Ang II-induced cardiomyocyte hypertrophy or interstitial fibrosis through a kinin/nitric oxide (NO)-dependent mechanism in mice. Ang II (1.4 mg/kg per day) or vehicle was subcutaneously infused into transgenic mice and wild-type mice for 14 days. The amount of cardiac AT2 receptor relative to AT1 receptor in transgenic mice was 22% to 37%. Ang II caused similar elevations in systolic blood pressure (by approximately 45 mm Hg) in transgenic mice and wild-type mice. Myocyte hypertrophy assessed by an increase in myocyte cross-sectional area, left ventricular mass, and atrial natriuretic peptide mRNA levels were similar in transgenic and wild-type mice. Ang II induced prominent perivascular fibrosis of the intramuscular coronary arteries, the extent of which was significantly less in transgenic mice than in wild-type mice. Inhibition of perivascular fibrosis in transgenic mice was abolished by cotreatment with HOE140, a bradykinin B2 receptor antagonist, or L-NAME, an inhibitor of NO synthase. Cardiac kininogenase activity was markedly increased (approximately 2.6-fold, P<0.001) after Ang II infusion in transgenic mice but not in wild-type mice. Immunohistochemistry indicated that both bradykinin B2 receptors and endothelial NO synthase were expressed in the vascular endothelium, whereas only B2 receptors were present in fibroblasts. These results suggest that stimulation of AT2 receptors present in cardiomyocytes attenuates perivascular fibrosis by a kinin/NO-dependent mechanism. However, the effect on the development of cardiomyocyte hypertrophy was not detected in this experimental setting. 相似文献
959.
Usefulness of carcinoembryonic antigen measurement in feces of patients with colorectal cancer 总被引:4,自引:0,他引:4
Dr. Takashi Shimano M.D. Hiroshi Okuda M.D. Takushi Monden M.D. Hideo Inaji M.D. Takesada Mori M.D. 《Diseases of the colon and rectum》1987,30(8):607-610
Anticarcinoembryonic antigen (CEA) antisera which showed no reactions with normal adult feces were prepared in guinea pigs. Using these, levels of CEA in feces from patients with colorectal carcinoma were measured by gel diffusion and rocket immunoelectrophoresis. Sixteen of 22 (73 percent) patients with carcinoma of the colon or rectum (Dukes' A4/6, B6/8, C6/7, D0/1) had detectable CEA in their feces, while none was detected in the feces of four patients with gastric ulcers or in those of 22 normal volunteers. Five of the 16 fecal CEA-positive patients showed no elevation of plasma CEA levels. Measurements using a commercial CEA kit (Abbott Laboratories) could not detect the differences between fecal CEA values of patients with colorectal carcinoma and benign diseases, or those of normal volunteers. These results suggest that measurement of fecal CEA by specific anti-CEA antisera will be valuable in screening and diagnosis of colorectal carcinoma. 相似文献
960.
Masahide?EbiEmail author Shoko?Nakagawa Yoshiharu?Yamaguchi Yasuhiro?Tamura Shinya?Izawa Yasutaka?Hijikata Takaya?Shimura Yasushi?Funaki Naotaka?Ogasawara Makoto?Sasaki Takashi?Joh Kunio?Kasugai 《International journal of colorectal disease》2018,33(12):1703-1708