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1.
To clarify the histological status of the pancreas tail after pancreatoduodenectomy (PD), fibrosis, islets of Langerhans, and A, B, and D cells were examined histometrically in surgical cases of pancreatic cancer. The same investigations were also performed during an autopsy examination of the pancreas tail of survivors of surgery who had received either PD or total pancreatectomy with segmental autotransplantation (SAT). In the surgical cases, fibrosis and the islet percentage compared with nonpancreatic cancer cases were significantly higher while the B cell ratio was significantly lower. In addition, in pancreatic cancer patients, the fibrosis and islet ratio in the group with a blocked pancreatic duct were higher while the B cell ratio was lower than in the group with an open pancreatic duct. A direct relationship between the islet ratio and the degree of fibrosis, and an inverse relationship between the B cell ratio and the degree of fibrosis, were thus found. From the autopsy cases, the fibrosis progressed and the islet ratio increased following PD, but after SAT only the islet ratio increased compared to the time of surgery. The progression of fibrosis after PD thus suggests the presence of some problems in both the surgical method and postoperative management.  相似文献   
2.
Background The antitumor effects of adoptive immunotherapy in combination with chemoradiotherapy were investigated in patients with oral squamous cell carcinoma. Methods Inductive chemoradiotherapy with peplomycin, 5-fluorouracil and60Co was given to 56 patients [CRI(−)group]. A local injection of adoptive lymphokine-activated killer (LAK) cells (≈2×108 cells) and small doses of interleukin-2(≈3×105 U) and interferon-gamma (≈2×105U) was given to 40 other patients in combination with the chemoradiotherapy [CRI(+) group]. Results Clinically, CR, PR, and LR were observed in 15 (37.5%), 24 (60.0%), and 1 (2.5%) of the patients in the CRI (+) group, respectively; and in 14 (25.0%), 38 (67.9%), and 4 of the patients (7.1%) in the CRI (−) group. The histopathological effects were correlated with the tumor remission rate, with lethal degeneration (grades III and IV), and prominent degeneration (grade IIB) in the tumor cells noted in 20 (50.0%) and 16 (40.0%) of the CRI(+) patients, respectively; and in 21 (37.5%) and 29 (51.8%) of the CRI (−) patients. Immunohistochemically, a prominent decrease of proliferating cell nuclear antigenpositive cells with a reciprocal increase of LeY-positve cells was induced by the chemoradioimmunotherapy. DNA fragmentation was observed in the mutant type p53-negative tumors in the CRI(+) group. Conclusion Adoptive immunotherapy with LAK cells and cytokines in combination with chemoradiotherapy induces advantageous anticancer effects resulting from necrosis and apoptosis.  相似文献   
3.
To establish a novel strategy for the control of fungal infection, we examined the antifungal and neutrophil-activating activities of antimicrobial peptides. The duration of survival of 50% of mice injected with a lethal dose of Candida albicans (5 × 108 cells) or Aspergillus fumigatus (1 × 108 cells) was prolonged 3 to 5 days by the injection of 10 μg of peptide 2 (a lactoferrin peptide) and 10 μg of α-defensin 1 for five consecutive days and was prolonged 5 to 13 days by the injection of 0.1 μg of granulocyte-monocyte colony-stimulating factor (GM-CSF) and 0.5 μg of amphotericin B. When mice received a combined injection of peptide 2 (10 μg/day) with amphotericin B (0.5 μg/day) for 5 days after the lethal fungal inoculation, their survival was greatly prolonged and some mice continued to live for more than 5 weeks, although the effective doses of peptide 2 for 50 and 100% suppression of Candida or Aspergillus colony formation were about one-third and one-half those of amphotericin B, respectively. In vitro, peptide 2 as well as GM-CSF increased the Candida and Aspergillus killing activities of neutrophils, but peptides such as α-defensin 1, β-defensin 2, and histatin 5 did not upregulate the killing activity. GM-CSF together with peptide 2 but not other peptides enhanced the production of superoxide (O2) by neutrophils. The upregulation by peptide 2 was confirmed by the activation of the O2-generating pathway, i.e., activation of large-molecule guanine binding protein, phosphatidyl-inositol 3-kinase, protein kinase C, and p47phox as well as p67phox. In conclusion, different from natural antimicrobial peptides, peptide 2 has a potent neutrophil-activating effect which could be advantageous for its clinical use in combination with antifungal drugs.  相似文献   
4.
Serotonin (5-HT) has been a candidate for neurotransmitters in cutaneous type I mechanoreceptors (i.e., Merkel cell-nerve endings). Although recent electrophysiological studies have suggested the presence of the 5-HT2 and 3 receptors in the Merkel cell-nerve endings, the histological localization of these receptors are obscure. We thus immunohistochemically examined the presence of 5-HT1, 2, 3 receptors in Merkel cell-nerve endings in sinus hair follicles of the rat whisker pad. We also studied the immunohistochemical localization of the 5-HT transporter to confirm the site of 5-HT secretion. For this purpose, we used antibodies for the 5-HT1A, 5-HT1B, 5-HT2A, 5-HT2C and 5-HT3 receptors, and for the 5-HT transporter, as well as antibodies for cytokeratin 20 (as a marker of Merkel cells) and neurofilament H (a marker of type I sensory nerve terminals). The immuno-stained sections were analyzed under a laser-scanning microscope. It was found that the sensory nerve terminals in the Merkel cell-nerve endings showed strong positive immunoreactions of 5-HT1A and 1B receptors but not 5-HT2A, 2C, and 3 receptors. Furthermore, both the Merkel cells and related axon terminals showed strong immunoreactions of the 5-HT transporter. These findings support the idea that 5-HT molecules are released from the Merkel cells during mechanical reception and indirectly regulate neural actions of sensory neurons via 5-HT1 receptors. The localization of the 5-HT transporter found in this study also suggests a possibility that axon terminals in the Merkel cell-nerve endings also release 5-HT.  相似文献   
5.
Endothelium-dependent vasodilation in type II diabetes mellitus   总被引:3,自引:0,他引:3  
Endothelial dysfunction is a major feature of atherosclerosis and it can also serve as an early atherosclerotic marker. Evaluation and assessment of the endothelial function is important to prevent serious atherosclerotic disease especially myocardial infarction, cerebrovascular disease and renal failure. To evaluate endothelial function we measured endothelium-dependent vasodilation (flow-mediated dilatation: %FMD) of the brachial artery with ultrasound. This method is non-invasive and can be repeatable in order to follow patients individually. Progressive atherosclerosis is often observed in diabetic patients who are not hypertensive. To evaluate the impairment of the endothelial function in type 2 diabetic patients, we examined %FMD in them and compared with hypertensive patients without diabetes and control subjects. We found that type 2 diabetic patients had the same endothelial dysfunction as hypertensive patients without diabetes. %FMD in both diabetic patients and hypertensive patients was lower than in control subjects. Moreover, %FMD of type 2 diabetic patients with hypertension was lower than %FMD of type 2 diabetic patients without hypertension. These finding suggests that endothelial dysfunction develops under the conditions of hypertension and hyperglycemia. Evaluating endothelial function with ultrasound is useful for assessment of atherosclerosis in diabetes.  相似文献   
6.
Type 2 diabetes is thought be a multifactorial disease and both genetic and acquired factors contribute its pathogenesis. Elucidation of susceptibility genes for type 2 diabetes thus leads to primary prevention for the disease. Although main susceptibility genes for type 2 diabetes have not been found, I present our data using candidate gene approach. Our data include the amylin gene S20G and the Pax4 gene R121W mutations and also include the muscle glycogen synthase gene M416V polymorphism that correlates to insulin resistance as a thrifty gene.  相似文献   
7.
Initiation and propagation reaction mechanisms of the anionic polymerization of hexafluoro-1,3-butadiene (HEBD) were investigated. The initiation reaction with caesium tert-butoxide was found to be completed within 5 min although the reactions were carried out at a much lower temperature than that of the polymerization reaction. The initiation reaction was, therefore, inferred to take place in an anionic fashion by adding the tert-butoxide anion to HFBD. In order to clarify the propagation reaction mechanism of HFBD which yielded a polymer with a polyvinylene structure, the polymerization reactivity of HFBD and hexafluoro-2-butyne (HFBY), the isomerization of HFBD to HFBY, and the structural difference between poly(HFBD) and poly(HFBY) were discussed. In spite of the low yield of HFBY by the isomerization reaction under polymerization conditions, higher yields of poly(HFBD) were obtained. Judging from the X-ray analysis which showed that poly(HFBD) was highly crystalline and poly(HFBY) was amorphous, poly(HFBD) might not be produced by polymerization of HFBY. An addition reaction of the propagating anion to the carbon-2 of the HFBD monomer followed by isomerization at the propagating living end to yield poly[1,2-bis(trifluoromethyl)vinylene] is proposed.  相似文献   
8.
本实验系应用荧光免疫组织化学的方法观察猴下位腰段椎旁交感神经节(L_(6-7))中神经肽Y,血管活性肠肽,降钙素基因相关肽,和P物质的存在、分布情况以及它们与酪氨酸羟化酶的共存关系。结果表明,大量细胞呈神经肽Y免疫反应阳性,它们在神经节周边分布更为密集。中等数量的血管活性肠肽阳性细胞和小量降钙素基因相关肽细胞散在于神经节内。在经含有Colchiciue的培养液离体孵育12h的标本上,可见中等数量的P物质免疫反应阳性细胞。根据抗酪氨酸羟化酶(TH)抗体的免疫染色结果,神经节内的神经元可分为TH~+和TH~-两群,前者占大多数。相邻切片免疫染色结果表明,几乎所有神经肽Y免疫阳性细胞同时含有TH,而所有血管活性肠肽免疫反应阳性细胞均呈酪氨酸羟化酶免疫反应阴性。神经肽Y与血管活性肠肽无共存关系。降钙素基因相关肽存在于部分血管活性肠肽免疫反应阳性细胞中,即属于VIP~+/TH~-组。从以上结果得出结论,在猴下位腰段椎旁交感神经节中,神经肽Y与血管活性肠肽分别存在于TH~+和TH~-两个细胞群。即神经肽Y存在于TH阳性神经元中,血管活性肠肽和降钙素基因相关肽则存在于TH阴性神经元中。  相似文献   
9.
10.
In order to analyze the phenotypic conversion of chondrocytes, mandibular condyles of mice and rabbits were cultured under cell and organ culture systems, and then examined by a combination of morphological and biochemical procedures. In organ culture, mandibular condylar cartilage (MCC) obtained from newborn mice began to mineralize from the central zone and then progressively widened towards the peripheral zone. Electron microscopic observations showed that with the increasing duration of the organ culture, chondrocytes at the central zone converted into spindle-shaped osteoblastic cells accompanying the formation of the bone type of thick-banded collagen fibrils. To obtain a better understanding of the chondrocytic conversion, immunolocalizations for type I and type X collagens and osteocalcin (OC) were examined in mouse MCC cells in cell culture. Type X collagen and OC were expressed almost simultaneously at the late stage of culture, and type I collagen was detected along the calcified nodues after the production of these proteins. Northern blot analysis in cell cultures of rabbit MCC indicated that type II collagen and alkaline phosphatase (ALPase) messenger ribonucleic acids (mRNAs) were highly expressed at day 7, but subsequently decreased. In contrast, mRNA for type I collagen was expressed at a low level on day 7 and peaked on day 12. The present results suggest that, morphologically and biochemically, cellular modification in MCC cells under culture conditions occurs at a cellular morphological level and also at marker-gene-expression level.  相似文献   
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