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101.
COLLETTE BRITTON GERMINAL J. CANTO GEORGEM. URQUHART MALCOLM W. KENNEDY 《Parasite immunology》1993,15(11):625-634
Immunofluorescence on live Dictyocaulus viviparus parasites revealed a significant antibody response by vaccinated and patently infected bovine hosts to the sheath of infective larvae (L3), a structure which is generally thought to be shed from the parasite surface prior to invasion of host tissue. In contrast, surface-exposed antigens of the adult, egg and pulmonary L1 stages were recognized only by serum antibody from calves exposed to a patent lungworm infection. Radioiodination of sheathed L3 identified a restricted set of components while a more complex pattern of labelled material was observed with adult parasites. Many more components of adult worms were labelled by the Bolton-Hunter than by the lodogen reagent, probably reflecting the more penetrative labelling propensities of the former. Stage-specificity of surface-associated antigens of adult parasites was demonstrated by their immunoprecipitation by antibody from patently-infected, but not from vaccinated, calves. There was no in vitro release of the major iodinatable surface-associated antigens of adult parasites nor any binding of antibody raised against adult excretory-secretory (ES) products to the surface of living adult worms, suggesting that surface components do not contribute to adult ES products in this species. Antibody responses to the surface of adults. L1 and eggs were specific to patently-infected animals and may provide a useful indicator of exposure to patent infection. 相似文献
102.
Shibahara Hiroaki; Shigeta Minoru; Inoue Miyuki; Hasegawa Akiko; Koyama Koji; Alexander Nancy J.; Isojima Sinzo 《Human reproduction (Oxford, England)》1996,11(12):2595-2599
The blocking effects of complement-dependent sperm immobilizingantibodies in the sera of infertile women and monoclonal antispermantibodies against humans and mice on fertilization were investigated.The hemizona assay (HZA) and sperm penetration assay (SPA) wereused to study the inhibitory effects of sera from 22 infertilepatients positive for sperm immobilizing antibodies. Use ofthese tests allowed us to differentiate whether the antibodyblocked spermzona pellucida tight binding and/or spermpenetration into the ooplasm. The zona pellucida penetrationassay (ZPA) was also used to study the effects of four monoclonalantibodies (mAbs) on human sperm penetration into the zona pellucida.Seven mAbs against murine spermatozoa were tested for theirinhibitory effects on in-vitro fertilization (IVF) and HZA inmice. Of 22 patient sera with sperm immobilizing antibodies,21 (95.5%) inhibited HZA attachment and penetration, whereasthis did not occur in any of 13 patient sera without these antibodies.However, 19 of 22 (86.4%) patient sera with sperm immobilizingantibodies and eight of 13 (61.5%) patient sera without theseantibodies inhibited the SPA. Two (2C6, 1G12) of four mAbs againsthuman spermatozoa showed strong inhibitory effects in all theassays (HZA, ZPA and SPA). One mAb (3B10) did not inhibit HZAbut blocked ZPA and SPA. Another mAb (H6-3C4) seemed to haveno inhibitory effects on fertilization. Two (Vx 5 and Vx 8)of seven mAbs against murine spermatozoa inhibited IVF in micebut did not block mouse HZA. These findings suggest that antispermantibodies block fertilization at specific stages. Some of themmay inhibit sperm capacitation and thus prevent all processesof fertilization that follow. Some other antibodies may notaffect capacitation and sperm binding to zona pellucida butinhibit the acrosome reaction, followed by the blocking of spermpenetration through zona pellucida and ooplasm. 相似文献
103.
MICHAEL W. STEWART PHILIP A. GORDON WAI S. ETCHES HALYNA MARUSYK SIBRAND POPPEMA COLIN BIGAMI† BRIAN SYKESI† 《British journal of haematology》1995,90(4):900-905
Summary. The association of cardiolipin with polystyrene beads was studied using 31P-NMR and electron microscopy. In the presence and absence of fetal calf serum, cardiolipin appeared to bind to the polystyrene beads in lamellar phase as assessed by 31P-NMR imaging. Electron microscopic analysis revealed an even coating of phospholipid about the beads with extensive micelle binding. Cardiolipin-coated beads challenged with ACA-positive sera followed by immunogold indicated antibody bound to micelles associated with the bead. Studies conducted with ACA IgG purified from patient sera indicated that some ACA bound to CL beads in the absence of a source of ACA cofactor (i.e. gelatin-blocked beads), some ACA required β2-GPI for binding (i.e. no binding in the presence of β2-GPI-depleted plasma), whereas other ACA which showed negliglible binding with gelatin-blocked beads, showed enhanced binding in the presence of /?2-GPI-depleted plasma. The data indicate that: (1) cardiolipin binds to polystyrene beads in lamellar phase, (2) ACA bind to phospholipid micelles bound directly to the polystyrene beads, and (3) ACA differ between individuals displaying varying phospholipid and phospholipid/cofactor substrate specificities. 相似文献
104.
对127例IgA肾病(IgAN)患者和25例非IgA系膜增殖性肾炎血清进行了抗内皮细胞抗体AECA的检测。结果表明:IgA肾病患者和非IgA系膜增殖性肾炎患者血清AECA-IgG较正常对照组高,而IgAN患者较非IgA系膜增殖性肾炎患者AECA-IgG的水平高,P〈0.05。IgAN患者的AECA-IgA水平较正常对照组高。IgAN患者按AECA水平分为阳性与阴性组,对两组硬化面积比进行比较,未见 相似文献
105.
Summary Epidermal growth factor (EGF) has been shown to stimulate DNA synthesis and cell division in normal glia. At least half of malignant human gliomas (MHG) express high levels of the EGF receptor (EGFR), which are above those detected in normal brain. The demonstration that antibodies against the EGFR inhibit the growth of squamous cell carcinoma line A-431, with large numbers of EGFR, in vitro and in vivo raises the possibility that these agents could be used therapeutically against malignant human gliomas either alone or conjugated to other agents. We have measured the growth effects of EGF and an anti-EGFR monoclonal antibody, 528 (Ab-528), on four well-characterized human malignant glioma cell lines, D-263 MG, D-247 MG, U-343 MGa Cl 26, and D-37 MG, with 2.9×104, 1.5×105, 8.6×105 and 1.59×106 EGFRs per cell, respectively. EGF significantly increased cell number in D-263 MG and D-37 MG by 65% and 74%, respectively, had no effect on D-247 MG, and significantly decreased cell number in U-343 MGa Cl 26 by 39%. U-343 MGa Cl 26 growth was inhibited 19% by Ab-528, but Ab-528 had no effect on growth of the other MHG lines. Ab-528 significantly inhibited all EGF-mediated growth effects. These studies demonstrate that, although Ab-528 alone has little antiproliferative activity on MGH, it successfully competes with EGF to reduce the biological effects of EGF-EGFR binding. Therefore, this antibody could potentially be used to target radioisotopes to MHG via the EGFR for diagnosis and therapy.Supported by Grants CA-11898, NS-20023, CA-43722, and the Association for Brain Tumor Research (MHW, PAH) 相似文献
106.
本文报道温抗体型自身免疫性溶血性贫血20例,其中包括特殊类型“兼有冷抗体和温抗体的自身免疫性溶血性贫血”3例,伴有血小板减少性紫瘢的Fisher—Evans综合征4例。并对本病致病因素、发病年龄、临床表现及特殊类型产生机理进行了讨论。 相似文献
107.
目的 检测黑龙江省2019—2021年肾综合征出血热(hemorrhagic fever with renal syndrome, HFRS)疑似患者血清标本中的汉坦病毒急性期和恢复期抗体水平,为该疾病防控提供科学依据。方法 应用酶联免疫吸附法对采集到的肾综合征出血热疑似患者急性期血清样本进行汉坦病毒IgM抗体检测,对恢复期血清标本进行IgM单抗体、IgG单抗体检测,使用SPSS 19.0软件对各年份间患者急性期血样IgM抗体阳性率进行χ2检验分析,使用EpiData 3.1和Excel2003软件对患者性别、职业、年龄、发病日期及初诊间隔时间数据进行整理分析。结果 共检测肾综合征出血热疑似患者急性期血清351份,恢复期血清208份。急性期血清标本IgM抗体阳性317份,阳性率为90.31%,各年份之间患者急性期IgM抗体阳性率差异无统计学意义(χ2=0.895,P=0.639)。患者恢复期血清IgM单抗体阳性32份(15.39%);血清IgG单抗体阳性28份(13.46%);IgM、IgG抗体双阳性148份(71.15%)。男女患者性别比4... 相似文献
108.
猪卵透明带单克隆抗体的研制 总被引:1,自引:1,他引:0
用热溶猪卵透明带抗原免疫BALB/C 小鼠,取其脾细胞和SP2/O 细胞融合产生的杂交瘤。用间接免疫荧光和ELISA 方法筛选,经四次克隆化后,获得三株分泌猪卵透明带单克隆抗体杂交瘤细胞株(LPD_8,LPC_4,LPD_2)。通过间接免疫荧光试验,其中二株单克隆抗体(LPD_8,LPC_4)与人卵透明带有交叉反应。但它们在猪与人卵透明带上呈现的荧光部位有明显的不同,LPD_8位于整个透明带上,而LPC_4只见于透明带外层。LPD_2荧光位于透明带内层且与人卵无交叉反应。我们认为这种差别是由于抗原决定簇的不同所致。 相似文献
109.
M. Shibuya F. Saito T. Miwa R. L. Davis C. B. Wilson T. Hoshino 《Acta neuropathologica》1992,84(2):178-183
Summary The growth potential of 65 pituitary adenomas was determined by histochemical analysis with Ki-67 and anti-DNA polymerase monoclonal antibodies, bromodeoxyuridine (BrdUdR) labeling, and counts of argyrophilic nucleolar organizer regions (Ag-NORs). The mean proliferating cell indices (PCIs) determined by Ki-67 and anti-DNA polymerase and the BrdUdR labeling index (LI) were generally very low [1.0±0.2%, 1.1±0.2%, and 0.5±0.1% (±SE), respectively]. Apart from adrenocorticotropic hormone-positive adenomas, which had significantly higher indices, there were no statistically significant differences in the indices among the other subtypes of pituitary adenomas. Recurrent tumors had higher Ki-67 and DNA polymerase PCIs and BrdUdR LIs (3.6%, 4.2%, 1.4%) than primary tumors (0.8%, 0.8%, 0.3%; P<0.005). The number of Ag-NORs did not correlated significantly with any of the three indices. The mean number of Ag-NORs was higher in nonfunctioning adenomas than in functioning adenomas (2.04 vs 1.66, P<0.005); among prolactin-positive adenomas, those treated preoperatively with bromocriptine had more Ag-NORs than untreated tumors (1.75 vs 1.57, P<0.005). These results suggest that the Ki-67 and DNA polymerase PCIs and the BrdUdR LI predict the growth potential of individual pituitary adenomas, whereas the number of Ag-NORs appears to correlate with hormone production rather than with the proliferative potential.Supported by grants CA-13525 and CA-50210 from the National Cancer Institute, by a grant from the Phi Beta Psi Sorority, and by Grant-in-Aid A 63771083 from the Ministry of Education, Science, and Culture of Japan 相似文献
110.
X. He C. J. Wikstrand P. Fredman J.-E. Månsson L. Svennerholm D. D. Bigner 《Acta neuropathologica》1989,79(3):317-325
Summary Seven monoclonal antibodies (mAbs) reactive with ganglioside II3(NeuAc)2-LacCer (GD3) were generated; four of these mAbs (DMAb-21, DMAb-22, DMAb-23, and DMAb-24) by immunizing mice with GD3 adsorbed to Salmonella minnesota and the remaining three (DMAb-7, DMAb-8, and DMAb-17) with melanoma line SK-MEL 28, which contains 1.4 nmol sialic acid of GD3 per mg protein. The specificities of the mAbs were defined by high-performance thin-layer chromatography (HPTLC) immunostain and solid-phase radioimmunoassay (SP-RIA) with a panel of purified gangliosides. DMAb-7 and DMAb-8 reacted with GD3, IV3(NeuAc)2nLcOse4Cer(3,8-LD1), and very weakly with IV3(NeuAc)2II3NeuAc-GgOse4Cer (GTla), but not with II3NeuAc-LacCer (GM3), II3NeuAcGgOse3Cer(GM2), II3NeuAc-GgOse4Cer(GM1), II3NeuAc, IV3NeuAcGgOse4Cer (GD1a), II3(NeuAc)2GgOse3(GD2), II3(NeuAc)2GgOse4Cer (GD1b), IV3NeuAcII3(NeuAc)2, GgOse4Cer(GT1b), suggesting the binding epitope to be a terminal tetrasaccharide NeuAc2-8NeuAc2-3Gal1-4(Glc or GlcNAc). DMAb-7 and DMAb-8 were used to investigate the expression of GD3 on cultured human tumor cells of neuroectodermal origin. Thirteen of 19 gliomas, 3 of 5 medulloblastomas, 5 of 5 neuroblastomas, 2 of 2 melanomas, and 1 of 3 teratomas were shown to react with DMAb-8 and/or DMAb-7 by cell surface-RIA (CS-RIA) and immunofluorescence (IF) assays. HPTLC and densitometric analysis confirmed these results, as positive immunostains in the GD3 region were obtained with oligoganglioside fractions from 9 glioma, 1 medulloblastoma, 2 neuroblastoma, 1 melanoma, and 1 teratoma cell line. Glioma cell line U-105 MG and medulloblastoma cell line Daoy contain GD3 as shown by HPTLC immunostain analysis of extracts, although GD3 was undetectable on the cell surface as determined by CS-RIA and IF. There was no detectable GD3 found in gangliosides isolated from cell lines U-373 MG, D-54 MG, TE-671, and PA-1, which were negative for both DMAb-7 and DMAb-8 by CS-RIA and IF assay. Our results provide evidence that GD3 is expressed extensively with significant quantitative heterogeneity on cultured human neuroectodermal tumor cells including glioma, medulloblastoma, neuroblastoma, and melanoma.Supported by NIH grants R37 CA11898, NS 20023, and CA32672 and by grants from the Swedish Medical Research Council (project no. 03X-627), Swedish Cancer Society (project no. 2260-B88-01X) and the National Swedish Board for Technical Development (project no. 84-4667) 相似文献