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The effect of acute and chronic cadmium (Cd) administration on the vascular function of the rat aorta was studied. The rats were randomly divided into four main groups (A: saline controls under chronic administration, B: Cd-treated rats under chronic administration, C: saline controls under acute administration, D: Cd-treated rats under acute administration). After their sacrifice, the aortic rings were divided into rings with endothelium (E+) and without (E−), and suspended in an isolated organ bath with Krebs–Henseleit buffer. Maximal tension (T max, in g) was measured in response to potassium chloride (KCl) and phenylephrine (PE) in all aortic rings. Relaxation response to acetylcholine (ACh) administration was expressed as percent of maximal tension induced by PE. Chronic administration: A statistically significant increase of the contraction was observed between groups B (i.m. Cd 0.5 mg/kg for 120 days) and A (i.m. 0.9% NaCl for 120 days) in response to KCl (20–60 mM) and the T max as well (in both the E+ and the E− subgroups). No statistically significant difference was observed in response to PE and ACh exposure. Acute administration: A statistically significant increase was observed between group D(E+) (i.m. Cd 2 mg/kg, 8 h before sacrifice) and group C(E+) (i.m. 0.9% NaCl, 8 h before sacrifice) in response to 10–30 mM of KCl, and a significant decrease between D(E−) and C(E−) in response to 10−7–10−6 M of PE, though T max was increased between D(E−) and C(E−) with PE exposure. The contractile response levels of the E+ aortic rings to PE and ACh showed no statistically significant difference.  相似文献   
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ABSTRACT

Eight taxa of the Dipsacaceae family were examined for their fatty acid and sterol composition. Separation and identification of the lipid fraction was achieved by gas chromatography and gas chromatography-mass spectrometry. The phenotypic differences among taxa were established by cluster analysis. Correlation coefficients were obtained to investigate numerical relationships among constituents of the fatty acids. The results showed many significant correlations between different constituents, as well as four clusters of taxa using two linkage types of clustering.  相似文献   
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BACKGROUND: Leptin, apart from the regulation of food intake, has been implicated in hematopoiesis, the immune response and angiogenesis. Leptin has been found to be decreased in various hematological malignancies. In the present study leptin was measured in multiple myeloma (MM) patients before and after treatment and correlated with other angiogenic molecules and markers of disease activity. METHODS: Serum leptin, vascular endothelial growth factor (VEGF), basic fibroblast growth factor (b-FGF), interleukin-1 beta (IL-1beta), beta 2 microglobulin (beta2M) and C-reactive protein (CRP) were measured in 62 newly diagnosed MM patients, 22 of whom obtaining disease stabilization after treatment. The same parameters were measured in 20 healthy controls. Disease stage was defined according to the Durie-Salmon criteria. RESULTS: Leptin, VEGF, b-FGF, IL-1beta, and beta2M were significantly higher in newly diagnosed MM patients than in controls (p<0.05). VEGF, b-FGF, IL-1beta, beta2M, CRP but not leptin increased with advancing stage of disease (p<0.01). All parameters decreased significantly following treatment (p<0.001). Although IL-1beta correlated positively with VEGF, beta2M, b-FGF and CRP, leptin did not correlate with any of the measured parameters. CONCLUSION: Leptin serum levels do not reflect disease severity in MM. However, there seems to be a decrease in leptin following treatment, which may be associated with an alteration in the metabolic state or the chemokine milieu.  相似文献   
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ABSTRACT: BACKGROUND: The choice of incision in any surgery is determined by access to the surgical field, particularly when oncologic resection is required. Special consideration is also given to postoperative pain and its sequelae, fewer complications in the early post-operative period and a lower occurrence of incisional hernias. The aim of this study was to compare two types of incision, a right-sided Kocher's incision (KI) and a midline incision (MI), for patients undergoing right hemicolectomy, by focusing on on both short-term and long-term results. METHODS: The hospital records for 213 patients who had undergone right hemicolectomy for a rightsided adenocarcinoma between 1995 and 2009 were retrospectively studied. In total, 113 patients had been operated via KI and 100 patients via MI. Demographic details, operative data (explorative access to the peritoneal cavity, time of operation), recovery parameters (time with intravenous analgesic medication, time to first oral fluid intake, first solid meal, time to discharge), and oncologic parameters (lymph-node harvest, tumor, node, metastasis (TNM) stage, and resection margins) were analyzed. Post-operative complications were also recorded. The two groups were retrospectively well matched with respect to demographic parameters and the oncologic status of the tumor. RESULTS: The median length of the MI was slightly longer (120 versus 100 mm, P < 0.05). The median duration of the surgery for the KI group was significantly shorter (70 versus 85 minutes, P < 0.001). In three patients we performed wedge resection of liver metastasis, and in one patient we performed a typical right hepatectomy, which lasted 190 minutes. No major operative complications were noted. There was no immediate or 30-day post-operative mortality. The KI group had a significantly shorter median hospital stay (5 days) than the MI group (8 days). All patients underwent wide tumor excision, and clear resection margins were obtained in all cases. No significant differences in analgesia requirement or early postoperative complications were noted. Late post-operative complications includedt hree cases of obstructive ileus (a single episode of each that resolved conservatively) and two cases of incisional hernias. CONCLUSIONS: The KIn approach for right-sided colon cancer is technically feasible, safe, andl very well tolerated overal. It can achieve the same standards of tumor resection and surgical field accessibility as the MI, with a reduction in post-operative recovery time.  相似文献   
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BACKGROUND: Efficient gene transfer to bone marrow derived mesenchymal stem cells (MSC) would provide an important opportunity to express potent anticancer agents in the tumour microenvironment because of their contribution to the tumour stroma. METHODS: HIV-based lentiviral vectors were pseudotyped with four different envelope proteins; amphotropic murine leukaemia virus (ampho), murine leukaemia virus (10A1), feline endogenous virus (RD114), and the vesicular stomatitis virus glycoprotein (VSVG). These pseudotypes were examined for transduction efficiency in human bone marrow derived MSC. The effect of lentiviral expression of truncated soluble vascular endothelial growth factor decoy receptor (tsFlk-1) in MSC on growth of Raji cells was determined, both in vitro and in vivo. RESULTS: All lentiviral vectors produced significant levels of transduction at an multiplicity of infection (MOI) of 1, those bearing the RD114 envelope glycoprotein consistently produced higher transduction levels (mean 70 +/- 6%) compared with the other pseudotyped lentiviral vectors, although there was significant inter-donor variation. Stable transgene expression was achieved after multiple rounds of transduction with VSVG-pseudotyped particles, without alteration in the differentiative capacity of transduced cells. Co-injection of MSC stably expressing tsFlk-1 with Raji Burkitt's lymphoma cells significantly impaired subcutaneous tumour growth in immunodeficient mice when compared to controls where either unmanipulated MSC or GFP-expressing MSC were used. CONCLUSIONS: Human MSC are easily transduced by pseudotyped lentiviral particles but there is inter-donor variation in transduction efficiency. Gene-modified MSC expressing a gene of therapeutic potential can moderate growth of haematological malignancies.  相似文献   
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Extended defects, including exposed surfaces and grain boundaries (GBs), are critical to the properties of polycrystalline solid electrolytes in all-solid-state batteries (ASSBs). These defects can alter the mechanical and electronic properties of solid electrolytes, with direct manifestations in the performance of ASSBs. Here, by building a library of 590 surfaces and grain boundaries of 11 relevant solid electrolytes—including halides, oxides, and sulfides— their electronic, mechanical, and thermodynamic characteristics are linked to the functional properties of polycrystalline solid electrolytes. It is found that the energy required to mechanically “separate” grain boundaries can be significantly lower than in the bulk region of materials, which can trigger preferential cracking of solid electrolyte particles in the grain boundary regions. The brittleness of ceramic solid electrolytes, inferred from the predicted low fracture toughness at the grain boundaries, contributes to their cracking under local pressure imparted by lithium (sodium) penetration in the grain boundaries. Extended defects of solid electrolytes introduce new electronic interfacial states within bandgaps of solid electrolytes. These states alter and possibly increase locally the availability of free electrons and holes in solid electrolytes. Factoring effects arising from extended defects appear crucial to explain electrochemical and mechanical observations in ASSBs.  相似文献   
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