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461.
462.
Six cases of gastric varices with multiple afferent veins, in which balloon-occluded venography of the draining vein showed insufficient filling of gastric varices with contrast medium, were treated by balloon-occluded retrograde transvenous obliteration (BRTO) and temporary balloon occlusion of the splenic artery. The gastric varices were completely filled with sclerosant in all but one patient. No procedure-related complications were encountered. Computed tomography (CT) after the procedure showed complete thrombosis of the varices in five patients and partial thrombosis in one patient. Temporary balloon occlusion of the splenic artery is a useful additional technique for complete obliteration of gastric varices in selected cases.  相似文献   
463.
A 60 year-old woman was admitted to our hospital because of management of multiple liver tumors. According to image findings and liver biopsy, she was diagnosed as having epithelioid hemangioendothelioma of the liver accompanied by metastases in the spleen, lungs and bones. Based on the spread of the liver tumors and the extensive systemic metastases, she was considered inoperable. Instead, she received hepatic arterial infusion therapy using recombinant interleukin-2. However, she died due to liver failure about two months after admission. Autopsy revealed that the liver tumor was angiosarcoma. It is difficult to differentiate angiosarcoma from epithelioid hemangioendothelioma based on the image findings and pathological findings of percutaneous liver biopsy. Many cases are diagnosed as angiosarcoma at autopsy. There is no established effective treatment for hepatic angiosarcoma, because the tumor stage at the time of diagnosis is often progressive. To date, immunotherapy with recombinant interleukin-2 has been reported to be effective clinically for cutaneous angiosarcoma, such as of the scalp and facial skin. To our knowledge, there have been no reported cases of hepatic angiosarcoma treated with recombinant interleukin-2. Our case is important should recombinant interleukin-2 be considered effective for hepatic angiosarcoma in the future.  相似文献   
464.
Invasion to lymphatic vessels and metastasis to lymph nodes are frequent complications in invasive micropapillary carcinoma (IMPC) of human breast cancer. Vascular endothelial growth factor-C (VEGF-C) and its receptor, VEGFR-3 have been implicated as the important factors in the formation of lymphatic vessels and recent experimental evidence strongly suggests that lymphangiogenesis in tumor promotes lymphatic metastasis. To clarify the mechanism of its occurrence, the expression of VEGF-C, VEGFR-3 and lymphatic vessel density (LVD) was examined in 40 cases of IMPC (pure and mixed type) and in 40 cases of pseudo-IMPC. Cytoplasmic expression of VEGF-C and VEGFR-3 were more frequent in tumor cells of IMPC compared to those of pseudo-IMPC. A significant positive correlation was found between the expression of VEGF-C and VEGFR-3 in both IMPC and pseudo-IMPC. The expression of VEGF-C was also significantly associated with higher peritumoral LVD, lymphatic invasion and number of lymph node metastasis in IMPC. These findings suggest that VEGF-C promotes the proliferation of peritumoral lymphatic vessels and that lymphatic invasion and metastasis to lymph nodes are frequently induced in IMPC of breast.  相似文献   
465.
The role of mouse peptidoglycan recognition protein PGLYRP-1 in innate immunity against Listeria monocytogenes infection was studied. The recombinant mouse PGLYRP-1 and a polyclonal antibody specific to PGLYRP-1 were prepared. The mouse PGLYRP-1 showed antibacterial activities against L. monocytogenes and other Gram-positive bacteria. PGLYRP-1 mRNA expression was induced in the spleens and livers of mice infected with L. monocytogenes. The viable bacterial number increased, and the production of cytokines such as gamma interferon (IFN-γ) and tumor necrosis factor alpha (TNF-α) was reduced in mice when mice had been injected with anti-PGLYRP-1 antibody before infection. The levels of IFN-γ and TNF-α titers in the organs were higher and the viable bacterial number was reduced in mice injected with recombinant mouse PGLYRP-1 (rmPGLYRP-1) before infection. PGLYRP-1 could directly induce these cytokines in spleen cell cultures. The elimination of intracellular bacteria was upregulated in NMuLi hepatocyte cells overexpressing PGLYRP-1. The enhancement of the elimination of L. monocytogenes from the organs was observed in IFN-γ(-/-) mice by rmPGLYRP-1 administration but not in TNF-α(-/-) mice. These results suggest that PGLYRP-1 plays a role in innate immunity against L. monocytogenes infection by inducing TNF-α.  相似文献   
466.
Guanine-rich oligonucleotides, such as TG(4)T and TG(5)T, assemble into a tetramolecular quadruplexes with layers of G-quartets stabilized by coordination to monovalent cations. Association rates of the quadruplexes are extremely slow, likely owing to electrostatic repulsion among the four strands. We have shown that comb-type copolymers with a polycation backbone and abundant hydrophilic graft chains form water-soluble polyelectrolyte complexes with DNA and promote DNA hybridization. Here, we report the effect of cationic comb-type copolymers on the kinetics of tetramolecular quadruplex formation. The copolymer significantly increased the association rate of tetramolecular quadruplexes without altering kinetic effects of metal cations in quadruplex formation. Dissociation rates of the quadruplexes were also accelerated by the copolymer suggesting that the copolymer has chaperone-like activity that reduces the energy barriers associated with dissociation and re-assembly of base pairs. This hypothesis was further supported by the observation that the copolymer activated the strand exchange reaction between the quadruplex and a constituting single-stranded.  相似文献   
467.
A 77-year-old man was transferred to the hospital with swelling of his neck and oropharynx after a stab injury to his oral cavity with pruning shears. Findings at complete neurologic examination were normal. Contrast-enhanced computed tomography (CT) and angiography revealed a pseudoaneurysm at the pharyngeal portion of the right internal carotid artery. Endovascular treatment was undertaken by using the double bare stent technique. The pseudoaneurysm was completely occluded immediately after the procedure. There were no complications. There were no further symptoms or evidence of recurrence of the aneurysm during the 18-month follow-up period. The double bare stent technique is safe and effective for the treatment of zone III carotid artery stab injuries.  相似文献   
468.
469.
In rodents, liver natural killer (NK) cells have been shown to mediate higher cytotoxic activity against tumor cells than do peripheral blood (PB) NK cells. However, such differences between liver and PB NK cells have not been extensively investigated in humans. The phenotypical and functional properties of NK cells extracted from liver perfusates at the time of living donor liver transplantation were investigated. The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a critical molecule for NK cell-mediated anti-tumor cell killing, was not expressed by freshly isolated PB NK cells or by liver NK cells. Stimulation with interleukin (IL)-2, significantly up-regulated the expression of TRAIL on liver NK cells, but this effect was barely observed on PB NK cells. Donor liver NK cells showed the most vigorous cytotoxicity against HepG2, a hepatocellular carcinoma (HCC) cell line, after IL-2 stimulation (90.5% +/- 2.2% at E: T = 10:1), compared with donor and recipient PB NK cells and recipient liver NK cells (64.8% +/- 8.2%, 56.1% +/- 8.9%, and 34.6% +/- 7.5%, respectively). IL-2 stimulation resulted in an increased expression of killing inhibitory receptors on liver NK cells in parallel with TRAIL expression. Consistently, the cytotoxicities of IL-2-stimulated donor liver NK cells against self and recipient lymphoblasts were negligible. In conclusion, adoptive transfer of IL-2-stimulated NK cells extracted from donor liver graft perfusate could mount an anti-tumor response without causing toxicity against 1-haplotype identical recipient intact tissues. These findings present a concept to prevent recurrence of HCC after liver transplantation.  相似文献   
470.
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