全文获取类型
收费全文 | 13563篇 |
免费 | 760篇 |
国内免费 | 65篇 |
专业分类
耳鼻咽喉 | 88篇 |
儿科学 | 218篇 |
妇产科学 | 217篇 |
基础医学 | 1841篇 |
口腔科学 | 584篇 |
临床医学 | 1010篇 |
内科学 | 3188篇 |
皮肤病学 | 261篇 |
神经病学 | 1086篇 |
特种医学 | 758篇 |
外科学 | 2091篇 |
综合类 | 79篇 |
预防医学 | 499篇 |
眼科学 | 335篇 |
药学 | 838篇 |
中国医学 | 17篇 |
肿瘤学 | 1278篇 |
出版年
2023年 | 75篇 |
2022年 | 110篇 |
2021年 | 280篇 |
2020年 | 140篇 |
2019年 | 172篇 |
2018年 | 288篇 |
2017年 | 207篇 |
2016年 | 265篇 |
2015年 | 245篇 |
2014年 | 313篇 |
2013年 | 369篇 |
2012年 | 669篇 |
2011年 | 743篇 |
2010年 | 376篇 |
2009年 | 340篇 |
2008年 | 606篇 |
2007年 | 620篇 |
2006年 | 668篇 |
2005年 | 626篇 |
2004年 | 588篇 |
2003年 | 614篇 |
2002年 | 617篇 |
2001年 | 424篇 |
2000年 | 464篇 |
1999年 | 463篇 |
1998年 | 168篇 |
1997年 | 139篇 |
1996年 | 118篇 |
1995年 | 82篇 |
1994年 | 105篇 |
1993年 | 106篇 |
1992年 | 322篇 |
1991年 | 310篇 |
1990年 | 274篇 |
1989年 | 273篇 |
1988年 | 287篇 |
1987年 | 246篇 |
1986年 | 227篇 |
1985年 | 211篇 |
1984年 | 158篇 |
1983年 | 100篇 |
1982年 | 54篇 |
1979年 | 122篇 |
1978年 | 67篇 |
1977年 | 60篇 |
1976年 | 58篇 |
1975年 | 61篇 |
1974年 | 56篇 |
1973年 | 54篇 |
1971年 | 53篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Y Akatsuka H Maeda S Tsuzuki T Sugihara S Minami Y Kodera K Koike 《[Rinshō ketsueki] The Japanese journal of clinical hematology》1992,33(3):322-327
The authors report an 18-year-old female who developed severe hemolytic reaction and delayed neutrophil recovery after bone marrow transplantation (BMT) for aplastic anemia from her HLA-identical sibling. She had received much transfusion (61 units of red blood cells including 4 units of fresh whole blood from her parents and 350 units of platelets) for 12 years before BMT. To prevent graft rejection, she received an intensified preparative regimen consisted of cyclophosphamide 200 mg/kg followed by 5 Gy total body irradiation and 5 Gy total lymphoid irradiation. Prophylaxis for GVHD was short term methotrexate and cyclosporin-A. Despite of the removal of the red cells from the marrow, marked hemolytic reaction caused by antibodies directed to rh" (E) and hr' (c) red cell antigens was observed when rh" (E) and hr' (c) positive donor erythroid began to recover. The recovery of neutrophils, especially the fraction of segmented cells was also delayed. Flow cytometry showed that the serially collected patient's sera reacted to neutrophils derived from both patient's blood on the 64th post-transplant day and the donor's blood. The reactivity was strongest in pre-BMT sera. We conclude that residual antibodies sensitized before BMT are a major cause of these hematological problems. 相似文献
72.
Kenjiro Shirasawa Keiichiro Akai Yukihiro Kawaguchi Shotaro Maeda Sadao Nagahara Hiroshi Toyoda Takeshi Kurata 《Pathology international》1979,29(3):435-455
A4-moth-old male infant predisposed to allergic dermatitis acquired widespread eczema vaccinatum by contacts with a recently vaccinated sibling. He died of acute purulent peritonitis following a perforation of multiple duodenal ulcers. Fluorescence immunocytochemical and electron microscopic studies on the skin lesions revealed the presence of viral antigens and numerous virus particles compatible morphologically with those of the mature form from the same batch of smallpox vaccine given to the sibling. A large number of virus particles in the developmental form were also predominantly scattered in the cytoplasm of cells at the stratum malpighii of the epidermis as well as in neutrophils and macrophages in the skin lesions. The virus isolation from the skin lesions was done by using the HeLa cells and the human embryonic lung fibroblasts. No abnormal laboratory data were noted in immunoglobulins. On the basis of atrophy of the thymus and other lymphatic tissues and an appearance of large pyroninophilic cells in association with blastoid transformation, the authors discussed a possible participation of the disturbance of cellular immunity secondary to the virus infection in the development of the disease. ACTA PATH. JAP. 29 : 435–455, 1979. 相似文献
73.
74.
Suzuki A Nozawa-Inoue K Ikeda N Amizuka N Ono K Takagi R Maeda T 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2005,286(2):908-916
Previous developmental studies on the temporomandibular joint (TMJ) have proposed several hypotheses on the formation of its articular cavity. However, detailed information is meager. The present study examined the formation process of the articular cavity in the rat TMJ by immunocytochemistry for CD31, RECA-1, and ED1, which are useful cellular markers for endothelial cells and monocyte/macrophage lineages, respectively. The upper articular cavity formation had begun by embryonic day 21 (E21) and was completed at postnatal day 1 (P1) in advance of the lower cavitation; the latter took place from P1 to P3. The occurrence and distribution pattern of the CD31-, RECA-1-, and ED1-positive cells differed between the upper and lower articular cavity-forming areas: the ED1-positive cells exclusively occurred in the area of the prospective upper articular cavity prior to its formation, while no ED1-positive cell appeared in the lower cavity-forming area. In contrast, the CD31- and RECA-1-positive endothelial cells were restricted to the lower cavity-forming area (never the prospective upper cavity) at E19 and diminished thereafter. Throughout the cavity formation, we failed to find any apoptotic cells in the cavity formation area, indicating no involvement of apoptosis in the cavity formation in TMJ. The present findings on the behaviors of endothelial cells and ED1-positive cells show a possibility of different mechanism in the cavity formation between the upper and lower articular cavities in the rat TMJ. The appearance of ED1-reactive cells and temporal vascularization may play crucial roles in the upper and lower articular cavity formation, respectively. 相似文献
75.
Immunofluorescence technique using HeLa cells expressing recombinant nucleoprotein for detection of immunoglobulin G antibodies to Crimean-Congo hemorrhagic fever virus
下载免费PDF全文
![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Saijo M Qing T Niikura M Maeda A Ikegami T Sakai K Prehaud C Kurane I Morikawa S 《Journal of clinical microbiology》2002,40(2):372-375
A HeLa cell line continuously expressing recombinant nucleoprotein (rNP) of the Crimean-Congo hemorrhagic fever virus (CCHFV) was established by transfection with an expression vector containing the cDNA of CCHFV NP (pKS336-CCHFV-NP). These cells were used as antigens for indirect immunofluorescence (IF) to detect immunoglobulin G antibodies to CCHFV. The sensitivity and specificity of this IF technique were examined by using serum samples and were compared to those of the IF technique using CCHFV-infected Vero E6 cells (authentic antigen). Staining of the CCHFV rNP expressed in HeLa cells showed a unique granular pattern similar to that of CCHFV-infected Vero E6 cells. Positive staining could easily be distinguished from a negative result. All 13 serum samples determined to be positive by using the authentic antigen were also determined to be positive by using CCHFV rNP-expressing HeLa cells (recombinant antigen). The 108 serum samples determined to be negative by using the authentic antigen were also determined to be negative by using the recombinant antigen. Thus, both the sensitivity and the specificity of this IF technique were 100% compared to the IF with authentic antigen. The novel IF technique using CCHFV rNP-expressing HeLa cells can be used not only for diagnosis of CCHF but also for epidemiological studies on CCHFV infections. 相似文献
76.
Hashii Koji; Fujiwara Hiroshi; Yoshioka Shinya; Kataoka Nobuhiko; Yamada Shigetoshi; Hirano Takeshi; Mori Takahide; Fujii Shingo; Maeda Michiyuki 《Human reproduction (Oxford, England)》1998,13(10):2738-2744
Human luteal cells have been reported to express human leukocyteantigen-DR and lymphocyte functional antigen-3 on the cell surface,suggesting physiological interaction between luteal cells andT-lymphocytes through the menstrual cycle into early pregnancy.To elucidate the role of peripheral lymphocytes on corpus luteumdifferentiation, the effect of peripheral blood mononuclearcells (PBMC) on steroidogenesis by luteal cells was investigated.The production of Th-2 cytokines such as interleukin (IL)-4and IL-10 by the co-cultured cells was also examined, and theeffects of these cytokines on progesterone production by lutealcells were investigated. Corpora lutea were obtained from eightnon-pregnant women in the luteal phase and five women in earlypregnancy for luteal cell culture. PBMC were isolated from unrelatedwomen in the follicular phase, secretory phase, and early pregnancy.After co-culture with allogenic PBMC for 48 h, progesteroneproduction was significantly enhanced by PBMC from the secretoryphase and early pregnancy in the non-pregnant luteal cell culture.In the pregnant luteal cell culture, a significant increasein progesterone production was also observed by the co-culturewith PBMC from women in early pregnancy, showing that PBMC havea luteotrophic effect. The stimulatory effects of PBMC werealso observed in co-culture conditions which prevented directcell-to-cell interaction with luteal cells, showing the minorinfluence of mixed lymphocyte reaction. By co-culture with PBMC,the production of IL-10, but not IL-4, was significantly augmentedin luteal cell culture derived from non-pregnant women, whereasthe production of both IL-4 and IL-10 was significantly enhancedin the luteal cell culture derived from pregnant women. Moreover,IL-4 and IL-10 promoted progesterone production by culturedluteal cells, especially in the luteal cell culture derivedfrom corpora lutea of early pregnancy. These findings indicatethat PBMC stimulate progesterone production by luteal cellsand suggest the involvement of PBMC in corpus luteum functionand differentiation probably via the Th-2-type lymphocytes. 相似文献
77.
Split tolerance between spleen and lymph node cells in severe combined immunodeficiency mice grafted with AKR fetal liver cells 总被引:1,自引:0,他引:1
Maeda Ken-ichi; Nagasawa Hideyuki; Furukawa Atsuko; Hisaeda Hajime; Himeno Kunisuke 《International immunology》1994,6(8):1213-1219
Severe combined Immunodeficient (SCID) mice defective in stemcells for T and B cells appear to be an ideal host for constructionof chimeric mice. When bone marrow cells are used as a sourceof stem cells, however, host SCID mice do not always show sufficientreconstitutlon. In this study, fetal liver cells from AKR embryoswere transplanted into SCID mice without prior irradiation.This treatment induced full reconstltution of lymphopoiesisas evaluated by flow cytometry analysis and serum Ig production2 months after transplantation. Thus, fetal liver cells seemto be a better source for reconstitutlon of SCID mice than bonemarrow cells. Lymph node (LN) cells of these mice (FLT mice)had no proliferatlve or cytotoxlc activities against eitherhost-type (C.B-17) or donor-type (AKR) spleen cells. However,spleen cells from FLT mice exhibited marked proliferatlve andcytotoxlc activities against C.B-17 cells, with no activitiesagainst AKR cells. Spirt tolerance against C.B-17 cells In spleenand LN cells was not a transient phenomenon, since similar resultswere obtained from a cytotoxic T lymphocyte assay 4 months later.In spite of the strong host reactivity in vitro, aberrationof clonal deletion or development of a graft-versus-host diseasewas not seen in FLT mice. As IL-2 induced the host reactivityof LN cells in a mixed lymphocyte reaction, potentially host-reactiveT cells were present in LN but were rendered anerglc. Tolerancein FLT mice seems to be regulated by a peripheral mechanism.We supposed that the split tolerance in FLT mice was inducedby the different antigenicity between the spleen and LN. 相似文献
78.
The structure of the avian fast skeletal muscle troponin T gene: seven novel tandem-arranged exons in the exon x region 总被引:1,自引:0,他引:1
Miyazaki J Jozaki M Nakatani N Watanabe T Saba R Nakada K Hirabayashi T Yonemura I 《Journal of muscle research and cell motility》1999,20(7):655-660
To elucidate the mechanism that produces enormous molecular diversity in troponin T (TnT) of fast skeletal muscle, we determined the 5-half genomic sequence of the chicken fast muscle TnT gene. The sequence of ca. 16 kb included seven exons (exons 1, 2, 3, 4, w, 5, and 6), which have been reported previously and presumed by sequencing TnT cDNAs. Additionally we found six 15 nt and one 18 nt sequences in the region between exons 5 and 6 (i.e. the exon x region). They were encompassed by consensus splice donor and acceptor sites and preceded by putative branch sites, and designated herein as exons xa to xg. Our result shows that the sequence derived from exons x1, x2, and x3, the exons presumed previously by cDNA sequencing, is actually encoded by the seven exons xa to xg, establishing the precise gene structure in the exon x region. Based on our data, together with that on the 3-half genomic sequence of the quail fast muscle TnT gene, we conclude that the avian fast skeletal muscle TnT gene includes 27 exons, 16 of which are alternatively spliced. 相似文献
79.
Nozawa-Inoue K Ohshima H Kawano Y Yamamoto H Takagi R Maeda T 《Archives of histology and cytology》1999,62(5):483-491
The expression of heat shock protein 25 (Hsp 25) was investigated in the rat temporomandibular joint by immunocytochemistry combined with confocal and electron microscopy. Immunostaining with an antibody to Hsp25 was able to demonstrate various cellular elements in the synovial membrane of the joint. Intense immunoreaction for Hsp25 was recognized in certain cells comprising the synovial lining layer. Confocal microscopic observation revealed two characteristic profiles of the Hsp25-positive cells with cytoplasmic processes: one extended thick and long processes towards the articular cavity, and the other prejected horizontally slender processes which covered the synovial membrane. Under the electron microscope, the immunoreactive synovial lining cells were characterized by a well-developed rough endoplasmic reticulum and secretory granules, suggesting that they can be categorized as fibroblastic type B cells. The covering by the cytoplasmic extensions was confirmed by immuno-electron microscopic observations. This cytoplasmic covering presumably performs a barrier function and expedites the effective secretion/resorption of synovial fluids. Since it has been proposed that Hsp 25 is associated with an estrogen receptor, the immunopositive synovial lining cells were considered estrogen-target cells. Immunoreactivity for Hsp25 was also observed in the chondrocytes of the maturative and hypertrophic cell layers as well as in the cells of the articular disk. A suggestion was made that Hsp25 might be involved in the inhibition of apoptosis of those cells. 相似文献
80.
Pathogenic capacity of proteases from Serratia marcescens and Pseudomonas aeruginosa and their suppression by chicken egg white ovomacroglobulin. 总被引:1,自引:3,他引:1
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The pathogenicities of three proteases from Serratia marcescens, two proteases from Pseudomonas aeruginosa, and one thermolysin from Bacillus stearothermophilus were examined. All proteases tested caused acute liquefactive necrosis of the cornea and descemetocele formation in guinea pig eyes after intrastromal injection, with the exception of the 60-kilodalton protease from S. marcescens, which produced only an opaque lesion. When injected into guinea pig skin, the protease also enhanced vascular permeability, which was followed by edema formation. The permeability-enhancing activity of the proteases increased in parallel with the concentration of the enzymes. When tested in vitro for its effect on these bacterial proteases, chicken egg white ovomacroglobulin (ovoM) inhibited the enzymatic activity of all the proteases after a short incubation period at an enzyme/inhibitor ratio (molar) of 1:1 to 1:4 or at a lower concentration after a longer incubation period. Such treatment of the proteases with chicken egg white ovoM before injection intrastromally into the eyes or intradermally into the clipped flanks of guinea pigs protected the cornea from destruction or completely prevented the permeability reaction and edema formation. No inhibitory effects of plasma protease inhibitors against these bacterial proteases were noted. Since the proteases are critical in the pathogenic processes caused by the bacteria, these results suggest a beneficial effect of ovoM against bacterial infections. 相似文献