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71.
We established an in vitro system generating L. monocytogenes-specific T cells primarily from unprimed spleen cells of mice. Normal spleen cells were cultured for 5 days in the presence of L. monocytogenes in vitro. Viable cells were harvested and assessed for their capacity to confer acquired cellular resistance (ACR) and delayed footpad reaction (DFR) upon local passive transfer to naive syngeneic recipient mice. When normal spleen cells were stimulated with viable L. monocytogenes, the viable cells that were recovered after 5 days of culture conferred a high level of ACR and DFR. Negative selection revealed that the effector cells obtained in primary in vitro culture were Thy 1+, L3T4+, Lyt2- cells. T cells mediating ACR could not be generated in the culture of normal spleen cells with heat-killed bacteria; however, cells mediating only DFR were generated in the presence of a large number of killed L. monocytogenes. The expression of DFR and ACR by T cells generated in this primary culture system was Listeria-specific; reactions were not observed against unrelated bacterial antigens including S. typhimurium, S. aureus, E. coli and PPD. FACS analysis of the cells in culture showed that L3T4+ and Lyt2- T cells were being enriched during culture. The primary generation of antigen-specific T cells in vitro was also possible with spleen cells from NTx mice but not with cells from nude mice, suggesting the presence of Listeria-specific precursors in NTx mice.  相似文献   
72.
In previous studies, we demonstrated that a hot water extract of Chlorella vulgaris (CVE) augmented the resistance against an intraperitoneal infection with Escherichia coli by its intraperitoneal, intravenous or subcutaneous administration. The augmented resistance appeared to be attributable to the enhanced activity of polymorphonuclear leukocytes (PMN). In this study, the effect of oral administration of CVE against Escherichia coli infection was examined. Male Fisher rats (F344/DuCrj) were administered 1000 mg/kg of CVE orally for 14 days and challenged with 2.7 x 10(8) Escherichia coli intraperitoneally. The numbers of living bacteria in the peritoneal cavity, blood, spleen and liver at 1, 6, and 24 h after the inoculation were counted. The bacterial numbers increased during 1-6 h and reached the peak at 6 h in both control and CVE-administered groups. The bacterial numbers decreased to an undetectable level at 24 h in both groups. In a CVE-administered group, the numbers of viable bacteria in each organ were remarkably lower than those in a control group in all organs so far tested. Whereas, the leukocyte numbers, especially PMN numbers, in the peritoneal cavity and peripheral blood maintained higher levels in the CVE-administered group at 6 h after E. coli inoculation. Chemiluminescent responses of peritoneal exudate cells induced by casein or E. coli were higher in a CVE-administered group. These results form the basis for the judgment that the degree of effectiveness of bacteria clearance from the peritoneal cavity shown by oral CVE administration may be strong enough to warrant developing this material as a new type of biological response modifier.  相似文献   
73.
BACKGROUND: A combination of pseudoaneurysm and arteriovenous fistula of the middle meningeal artery is rare. We describe a case of traumatic pseudoaneurysm of the middle meningeal artery, which subsequently formed a fistula with the cavernous sinus. CASE DESCRIPTION: A 23-year-old man suffered from blunt head trauma and skull fractures. Sixteen days later, he suddenly experienced headache and a bruit was auscultated over the left ear. Three-dimensional computed tomographic angiography revealed dilatation of the left middle meningeal artery. The dilation proved to be a pseudoaneurysm on cerebral angiograms and it was also found to have formed a fistula with the cavernous sinus. Both lesions were successfully obliterated by endovascular embolization using microcoils. CONCLUSION: Head injury may lead to asymptomatic pseudoaneurysm or dural arteriovenous fistula. Neurosurgeons should always bear in mind the possibility of such vascular injuries after blunt head trauma to prevent any hemorrhagic complications.  相似文献   
74.
Abdominal lymphangioma is usually diagnosed within the first 2 years of life and is extremely rare in adults. The most common location of abdominal lymphangioma is the mesentery, but there are sporadic reports of its development in the gallbladder. A 66-year-old woman was found to have a cystic lesion near the gallbladder. Preoperative studies, including endoscopic ultrasonography, computed tomography, and magnetic resonance imaging, showed a tumor with multilocular cystic structure, originating in the gallbladder fossa. The patient underwent exploratory laparotomy, and the mass was resected en bloc with the gallbladder, as there was no evidence of malignancy on intraoperative ultrasonography. Macroscopically, the tumor was a multilocular cystic mass, 6 × 3 × 2 cm in size, with a rough, sponge-like appearance. Histologically, the cystic tumor was diagnosed as a lymphangioma, originating in the gallbladder. To our knowledge, only three other cases of a cystic lymphangioma originating in the gallbladder have been reported in the medical literature of the world.  相似文献   
75.
目的:研究螺旋CT检测冠状动脉钙化(CAC)在冠心病诊断中的应用价值。方法:27例既往确诊为冠心病或经心电图负荷试验和/或冠状动脉造影临床确诊的冠心病患(冠心病组)和35例非冠心病患(对照组)分别进行螺旋CT检查。结果:受检随着年龄的增长钙化率逐渐增高,冠心病组冠状动脉钙化率比对照组明显增高,但随年龄的增长冠心病组钙化的特异性降低(降至11.12%)。钙化血管以累及一支血管最常见,多为左前降支(LAD),三支血管钙化主要见于60岁以上。结论:螺旋CT检测冠状动脉钙化对早期诊断冠心病和预测冠心病事件有与病理相符的临床价值。  相似文献   
76.
From a series of 152 renal biopsy specimens examined by light, immunofluorescence, and electron microscopy, nine specimens were identified as being from patients with BRH. Histopathologic changes in renal biopsy specimens from most of the 9 patients consisted of either normal or slightly proliferative glomerulonephritis. Characteristic alterations were observed by electron microscopy, which showed the presence of small amounts of electron-dense deposits within the mesangium. In addition, immunofluorescent staining of peripheral blood lymphocytes from patients with BRH and their family members showed an increase of IgA-bearing peripheral blood lymphocytes, and the emergence of microhematuria among the families of patients with BRH indicates that some familial factors may be involved in the development of BRH and IgA nephropathy, which suggests that these two disorders may be closely related.  相似文献   
77.
To evaluate the hypothesis that gamma delta T cells participate in protective immunity against mycobacterial infection, we depleted gamma delta T cells from mice by administration of anti-T-cell receptor (TCR)gamma delta monoclonal antibody (mAb) and analysed protection against Mycobacterium bovis bacillus Calmette-Guérin (BCG). The gamma delta T-cell-depleted mice did not show any exaggerated bacterial multiplication compared with control mice. In contrast, alpha beta T-cell-depleted mice, which were administrated anti-TCR alpha beta mAb before BCG infection, showed a depressed protective immunity. These results suggest that gamma delta T cells are not essential for coping with a primary BCG infection.  相似文献   
78.
Y Maeda  Y Koga  K Tanaka  X Y Zhang    K Nomoto 《Immunology》1993,79(2):196-202
It becomes increasingly clear that adhesion systems such as CD2/LFA-3 (lymphocyte function-associated antigen-3), LFA-1/ICAM-1 (intercellular adhesion molecule-1) and Thy-1/putative Thy-1 ligand participate in the association between murine thymocytes and thymic epithelial cells. In the present study, thymocytes showed an increase in surface Thy-1 levels in mice infected with Listeria monocytogenes, but no significant changes in the levels of CD2 or LFA-1. No alteration was found either in the ratio of CD3high/CD3low/CD3- or in that of CD4/CD8 subsets in these thymocytes compared with uninfected control thymocytes which excluded the possibility of enrichment of 'cortical thymocytes' with Thy-1high/CD3low/CD4+ CD8+ in the thymocyte population of infected mice. Moreover such Thy-1high thymocytes exhibited a highly augmented ability of adhesion to a thymic epithelial cell line due to the increase of surface Thy-1 antigens as an adhesion molecule. At such intervals after infection, the total number of thymocytes was found to be reduced. These results suggest that the expression level of surface Thy-1 on thymocytes is regulated in response to in vivo stimulation and may play a role in the intrathymic development of thymocytes by affecting the adhesion of thymocytes with thymic stromal cells. The implication of the enhanced ability of adhesion in the decrease in the number of thymocytes is discussed.  相似文献   
79.
80.
We compared the effects of in vivo administration of the anti-T-cell receptor (TCR) alpha beta monoclonal antibody (mAb) (H57-597) to those of the anti-CD3 mAb (145-2C11), with or without anti-NK1.1 mAb (PK136), on xenogeneic skin graft survival in mice. In anti-TCR alpha beta mAb-treated B6 mice, F344 rat skin grafts survived for about 54 days, whereas in anti-CD3 mAb-treated B6 mice with or without anti-NK1.1 mAb treatment grafts survived about 25 days. In anti-TCR alpha beta mAb-treated B6 mice, TCR alpha beta-bearing T-lymphocyte function was completely abrogated, although TCR gamma delta-bearing T-lymphocyte function was still intact on day 9. In the anti-CD3 mAb-treated mice, the functions of both types of T lymphocytes were completely abrogated. On day 32, when most of the skin xenografts had been rejected in the anti-CD3 mAb-treated mice, the functions of both T lymphocytes had recovered considerably, and could actually respond to F344 antigens. In contrast, the function of TCR alpha beta-bearing cells had only partially recovered in the anti-TCR alpha beta mAb-treated mice. Finally, natural killer (NK) activity in the anti-TCR alpha beta mAb-treated mice was intact on day 32, when rat skin grafts still survived. In contrast, NK activity in the anti-CD3 mAb plus anti-NK1.1 mAb-treated mice did not recover on day 32, when skin xenografts had already been rejected. These results suggest that TCR gamma delta-bearing T cells and NK cells by themselves, at least in the absence of TCR alpha beta-bearing T cells, do not mediate xenogeneic skin graft rejection in mouse/rat combinations.  相似文献   
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