全文获取类型
收费全文 | 6084篇 |
免费 | 278篇 |
国内免费 | 37篇 |
专业分类
耳鼻咽喉 | 116篇 |
儿科学 | 99篇 |
妇产科学 | 155篇 |
基础医学 | 813篇 |
口腔科学 | 182篇 |
临床医学 | 455篇 |
内科学 | 1359篇 |
皮肤病学 | 46篇 |
神经病学 | 613篇 |
特种医学 | 381篇 |
外国民族医学 | 1篇 |
外科学 | 825篇 |
综合类 | 58篇 |
预防医学 | 274篇 |
眼科学 | 69篇 |
药学 | 446篇 |
中国医学 | 9篇 |
肿瘤学 | 498篇 |
出版年
2023年 | 28篇 |
2022年 | 43篇 |
2021年 | 107篇 |
2020年 | 66篇 |
2019年 | 103篇 |
2018年 | 110篇 |
2017年 | 67篇 |
2016年 | 77篇 |
2015年 | 99篇 |
2014年 | 138篇 |
2013年 | 172篇 |
2012年 | 255篇 |
2011年 | 317篇 |
2010年 | 198篇 |
2009年 | 148篇 |
2008年 | 250篇 |
2007年 | 262篇 |
2006年 | 299篇 |
2005年 | 246篇 |
2004年 | 291篇 |
2003年 | 309篇 |
2002年 | 294篇 |
2001年 | 179篇 |
2000年 | 204篇 |
1999年 | 170篇 |
1998年 | 79篇 |
1997年 | 66篇 |
1996年 | 62篇 |
1995年 | 58篇 |
1994年 | 39篇 |
1993年 | 47篇 |
1992年 | 176篇 |
1991年 | 142篇 |
1990年 | 142篇 |
1989年 | 154篇 |
1988年 | 129篇 |
1987年 | 104篇 |
1986年 | 107篇 |
1985年 | 87篇 |
1984年 | 64篇 |
1983年 | 67篇 |
1981年 | 24篇 |
1980年 | 32篇 |
1979年 | 41篇 |
1977年 | 28篇 |
1974年 | 29篇 |
1973年 | 29篇 |
1972年 | 25篇 |
1971年 | 26篇 |
1966年 | 26篇 |
排序方式: 共有6399条查询结果,搜索用时 15 毫秒
81.
Tohru Hayashi Akinobu Sumiyoshi Masayuki Tanaka Shukurou Araki Yoichi Minamishima 《Pathology international》1985,35(1):173-181
Clinical, light- and electron microscopic, and immunohistochemical findings of a 44-year-old woman with progressive multifocal leukoencephalopathy were presented. Autopsy revealed a wide distribution of the demyelinating lesion in the cerebrum, cerebellum, brain stem and spinal cord, and intranuclear inclusion bodies and papova-like virions in transmission electron microscopy in the nuclei of oligodendrocytes. SV40 antigen was immunohistochemically detected in these inclusion bodies. The widespread extension of the lesions seemed to correlate with the duration of the patient's illness. The prolongation of the clinical course in this case may be dependent upon the lack of serious underlying diseases except for a small nodule of thyroid carcinoma, SV40 infection rather than JC virus infection and/or improved care of that kind of patient. 相似文献
82.
Kazuo Watanabe Atsuko Saito Hironao Wakabayashi Takanori Kawaguchi Toshimitsu Suzuki 《Pathology international》1991,41(6):461-465
Two autopsy cases of leiomyosarcoma of the liver in a 49-year old female and 63-year-old male are reported. Both of the liver tumors showed electron microscopically dense patches in the cytoplasm and intermediate junctions between the tumor cells, suggesting a smooth muscle cell origin, irrespective of their different histological features. The nature of both tumors was confirmed by positive immunoreactivity for muscle-specific actin in the tumor cells, whereas desmin immunoreactivity was labile in both cases, showing a higher diagnostic value of the former compared with the latter in these leiomyosarcomas. Both cases, showed extensive distant metastases in spite of an evident difference in their mitotic indices, indicating that this index is not reliable for judging the metastatic potential of these tumors. Acta Pathol Jpn 41: 461–465, 1991. 相似文献
83.
Toshio Morohoshi Tetsuya Hamamoto Toshiaki Kunimura Etsuko Yoshida Mikio Kanda Kenichi Funo Takehisa Nagayama Masayuki Maeda Shunji Araki 《Pathology international》1991,41(12):916-921
A rare case of splenic epidermoid cyst (SEC) of the pancreas discovered in a 32-year-old Japanese female is reported. The lesion, 5x6cm in size including caseous material and serous fluid in the lumen, was discovered by ultrasonography and computed tomography at the tail of the pancreas and was easily removed. Histopathologically, the cystic wall consisted of three components: the inside was lined by mature squamous epithelium with keratinization, the middle layer consisted of splenic pulp with a sinus structure, and the peripheral layer was dense fibrous connective tissue in which some involutional pancreatic ducts and islets were recognized. The literature about SEC of the pancreas is discussed in comparison with other types of epidermoid cyst including lymphoepithelial cyst and dermoid cyst in the pancreas. Acta Pathol Jpn 41: 916 921, 1991. 相似文献
84.
85.
Multiple epithelial cysts of the spleen and on the splenic capsule, and high serum levels of CA19-9, CA125 and soluble IL-2 receptor 总被引:1,自引:0,他引:1
Hashimoto T Sugino T Fukuda T Hoshi N Ogura G Watanabe K Satoh Y Hasegawa T Ohishi A Haga J Miyata M Suzuki T 《Pathology international》2004,54(5):349-354
An 18-year-old woman with abdominal pain was diagnosed as having splenic cysts by computed tomography scan. She had high serum levels of CA19-9 (2886.8 U/mL; normal value, <35 U/mL), CA125 (131.1 U/mL; normal value, <35 U/mL) and soluble IL-2 receptor (1490 U/mL; normal range, 220-530 U/mL). The resected spleen weighed 1050 g, was 14 x 28 cm, and had more than 10 macroscopic cysts up to 10.3 x 9.5 cm. There were numerous microscopic cysts in the spleen and several on the splenic capsule. The levels of CA19-9 and CA125 in the cyst fluid were 2165550 U/mL and 160400 U/mL, respectively. After the surgery, the serum levels of the tumor markers decreased gradually. The inside of the largest cyst was mainly covered by granulation tissue with a focal lining of epithelial cells, and the other macroscopic cysts had stratified squamous epithelium. The microscopic splenic cysts and cysts on the splenic capsule were lined by either attenuated single-layered or multilayered epithelial cells. The lining epithelial cells of these cysts were positive for epithelial membrane antigen and cytokeratins. CA19-9 and CA125 were detected in the lining cells of the splenic cysts. In the present case, it is suspected that the splenic cysts were derived from the capsular lining cells that showed migration from the capsule or formed microcysts on the splenic capsule, as in the case of ovarian inclusion cysts. 相似文献
86.
Comparison of high-energy photon and electron dosimetry for various dosimetry protocols 总被引:1,自引:0,他引:1
The American Association of Physicists in Medicine Task Group 51 (TG-51) and the International Atomic Energy Agency (IAEA) published a new high-energy photon and electron dosimetry protocol, in 1999 and 2000, respectively. These protocols are based on the use of an ion chamber having an absorbed-dose to water calibration factor with a 60Co beam. These are different from the predecessors, the TG-21 and IAEA TRS-277 protocols, which require a 60Co exposure or air-kerma calibration factor. The purpose of this work is to present the dose comparison between various dosimetry protocols and the AAPM TG-51 protocol for clinical reference dosimetry of high-energy photon and electron beams. The absorbed-dose to water calculated according to the Japanese Association of Radiological Physics (JARP), International Atomic Energy Agency Technical Report Series No. 277 (IAEA TRS-277) and No. 398 (IAEA TRS-398) protocols is compared to that calculated using the TG-51 protocol. For various Farmer-type chambers in photon beams, TG-51 is found to predict 0.6-2.1% higher dose than JARP. Similarly, TG-51 is found to be higher by 0.7-1.7% than TRS-277. For electron beams TG-51 is higher than JARP by 1.5-3.8% and TRS-277 by 0.2-1.9%. The reasons for these differences are presented in terms of the cavity-gas calibration factor, Ngas, and a dose conversion factor, Fw, which converts the absorbed-dose to air in the chamber to the absorbed-dose to water. The ratio of cavity-gas calibration factors based on absorbed-dose to water calibration factors, N60Co(D,w), in TG-51 and cavity-gas calibration factors which are equivalent to absorbed-dose to air chamber factors, N(D,air), based on the IAEA TRS-381 protocol is 1.008 on average. However, the estimated uncertainty of the ratio between the two cavity-gas calibration factors is 0.9% (1 s.d.) and consequently, the observed difference of 0.8% is not significant. The absorbed-dose to water and exposure or air-kerma calibration factors are based on standards traceable to the National Institute of Standards and Technology (NIST). In contrast, the absorbed-dose to water determined with TRS-398 is in good agreement with TG-51 within about 0.5% for photon and electron beams. 相似文献
87.
Characterization of T-cell tolerance to hepatitis B virus (HBV) antigen in transgenic mice. 总被引:3,自引:0,他引:3
下载免费PDF全文
![点击此处可从《Immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
We made three different lines of hepatitis B virus (HBV) transgenic mice which express different amounts of hepatitis B e antigen (HBeAg) and/or hepatitis B core antigen (HBcAg) to analyse the cellular mechanisms of HBcAg specific T-cell tolerance. BS10 (official designation, 1.2HB-BS10) transgenic mice, which contain the whole HBV genome, express relatively high amounts of HBeAg in the serum and HBcAg in the liver. SPC mice, which contain hepatitis B virus core and precore gene, express small amounts of HBeAg in the serum but not HBcAg in the liver. SC33 mice, which contain only hepatitis B core gene, do not express HBeAg in the serum but express HBcAg in the liver. BS10 mice showed a very low anti-HBc antibody response after primary and secondary immunizations with recombinant HBcAg compared to transgenic host C57BL/6 (B6) mice. SPC mice showed an almost equal level of anti-HBc antibody response compared to B6 mice. SC33 mice contained anti-HBc antibody even before immunization and showed high titres of anti-HBc antibody response after immunization with HBcAg. Analysis of cellular site(s) of low responsiveness of BS10 mice revealed that proliferating and helper T cells are specifically tolerant to HBcAg. B cells and antigen-presenting cells in BS10 mice were not defective. SC33, SPC and BS10 mice differ a little in their developmental expression of HBc/HBeAg. Our results suggest critical roles of the nature (circulating versus non-circulating) as well as the time of expression of self-antigens in T-cell tolerance. 相似文献
88.
Structure of the functional interleukin-2 receptor: Evidence for the association of human p55 and murine p75 molecules in a mouse T cell line 总被引:2,自引:0,他引:2
Yamaguchi Akira; Ide Takashi; Hatakeyama Masanori; Doi Takeshi; Kono Takeshi; Uchiyama Takashi; Kikuchi Kokichi; Taniguchi Tadatsugu; Uede Toshimitsu 《International immunology》1989,1(2):160-168
The structural basis of the high affinity interleukin-2 receptorwhich was previously reconstituted in a cultured murine T cellline, EL4 by expressing either wild-type Tac antigen complementaryDNA (cDNA) or a chimeric cDNA was characterized. The chimericcDNA encodes a membrane portion whose extracellular portionconsists of that of Tac antigen whereas transmembrane and cytoplasmicportions consists of those the human insulin beta chain. TheTac antigen/anti-Tac antibody complex was treated by chemicalcrosslinking reagents, purified by goat anti-mouse immunoglobulin(lg), and was analysed by SDS–PAGE. We here demonstrated the presence in mouse EL4 transfectantsof a novel membrane protein which is closely associated withthe products of transfected cDNAs in the absence of interleukln-2.The protein is 75 kDa in size and is detected in cells whichexpress high affinity interieukln-2 receptor but not in cellswhich only express low affinity interleukin-2 receptor. Thetransmembrane region and the cytoplasmic region of Tac antigenis not necessary for the formation of the complex consistingof Tac antigen and 75 kDa molecule, indicating that a murine75 kDa molecule associates with Tac antigen extra-cellularly. 相似文献
89.
Immunohistochemical profile of primary sclerosing Iipogranuloma of the scrotum: Report of five cases
Kazuo Watanabe Nobuo Hoshi Kei-ichi Baba Takeaki Fukuda Hando Hakozaki Toshimitsu Suzuki 《Pathology international》1995,45(11):854-859
Five cases of primary sclerosing scrotal lipogranuloma were examined histologically and immunohistochemically. Every case lacked a history of injection or trauma, and revealed Common histologicat features; a typical granuloma composed of epithelioid cells and multinucleated giant cells, and inflammatory infiltrates of eosinophils, lymphocytes and macrophageimonocytes in the interstitium. lmmunahistochemistry disclosed the epithelioid cells and multinuclaated giant cells of the granuloma to be monocytetr in nature, as bath types of cells were positive for lyso-yme, α-1-antltrypin, α-1-antichymotrypsin, and KP-1. In the interstitium, KP-1 positive monocytes, L-26 positive B lymphocytes, UCHL-1 positive T lymphocytes and 5–100 protein positive Langerhans-like cells were frequently found. 5100 protein positive cells could not be detected in the granuloma. Primary sclerosing lipogranuloma of the scrotum, therefore, is a peculiar inflammation characterized by granulomas consisting of monocytes and marked tissue eosinophilia of unknown etiology. 相似文献
90.
H Wakiguchi A Maeda Y Ohara Y Tone K Araki T Shiraishi H Ogura I Kitamura 《The Japanese journal of antibiotics》1985,38(7):1925-1930
Clinical application to ascertain the effects of aspoxicillin (ASPC), a new semisynthetic penicillin antibiotic, upon several infectious diseases of children was performed in 7 cases with pneumonia, 5 cases with acute bronchitis, each case with tonsillitis, enterocolitis, urinary tract infection and suspected sepsis. ASPC was injected by drip infusion and the dosage was 63-117 mg/kg/day in 3 and 4 times a day. Clinical efficacy obtained as "excellent" was in 7 cases, "good" in 8 cases "poor" in 1 case, and efficacy rate was 93.8%. From the bacteriological point of view, eliminated in each of H. influenzae, H. parainfluenzae, group A beta-Streptococcus and unchanged in a case of E. coli. There were transient thrombocytopenia in 2 cases and eosinophilia in 3 cases. 相似文献