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51.
Effective chemotherapy for pancreatic cancer is urgently needed. The aim of this study was to compare the anti-proliferative activity on pancreatic cancer cell lines of the vitamin D(3) analog, 22-oxa-1,25-dihydroxyvitamin D(3), maxacalcitol, with that of 1,25-dihydroxyvitamin D(3), calcitriol, with analysis of vitamin D receptor status and the G(1)-phase cell cycle-regulating factors. Antiproliferative effects of both agents were compared using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method and by measuring the tumor size of xenografts inoculated into athymic mice. Scatchard analysis of vitamin D receptor contents, and mutational analysis of receptor complementary DNA were performed. Levels of expression of cyclins, cyclin-dependent kinases and cyclin-dependent kinase inhibitors, p21 and p27, were analysed by western blotting. In vitro, maxacalcitol and calcitriol markedly inhibited the proliferation and caused a G(1) phase cell cycle arrest with the appearance of numerous domes. In vivo, maxacalcitol inhibited the growth of BxPC-3 xenografts more significantly than calcitriol, without inducing hypercalcemia. Responsive cells had abundant functional vitamin D receptors. However, Hs 766T, showing no response to either agent, had the second highest receptor contents with no abnormalities in its primary structure deduced by receptor complementary DNA. In the responsive cells, p21 and p27 were markedly up-regulated after 24h of treatment with both agents. In non-responsive cells, no such changes were observed. In conclusion, maxacalcitol and calcitriol up-regulate p21 and p27 as an early event, which in turn could block the G(1)/S transition and induce growth inhibition in responsive cells, and maxacalcitol may provide a more useful tool for the chemotherapy of pancreatic cancer than calcitriol because of its low toxicity.  相似文献   
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We isolated a total of 266 strains of lactic acid bacteria (LAB) from 28 dahi samples that were collected from different areas in Bangladesh. The isolated strains were identified on basis of their morphological, physiological and biochemical characteristics, the lactic acid isomer produced, the ability to ferment sugars and 16S rDNA analysis. Among the isolates, the cocci (73%) were dominant over the rods (27%). The distribution of the isolates by genus was as follows: Streptococcus (50%), Lactobacillus (27%), Enterococcus (9%), Leuconostoc (5%), Lactococcus (5%) and Pediococcus (4%). In this study, S. bovis was the most predominant species as this species represents 47.0% of the total isolates in dahi. The other species we isolated were identified as Lb. fermentum, Lb. delbrueckii ssp. bulgaricus, Lb. delbrueckii ssp. lactis, Lb. sp., Ec. faecium, S. thermophilus, Leuc. mesenteroides ssp. mesenteroides, Leuc. mesenteroides ssp. dextranicum, Lc. lactis ssp. lactis, Lc. raffinolactis and P. pentosaceus.  相似文献   
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Quantitative PCR is becoming widespread for diagnosing and monitoring post‐transplantation diseases associated with EBV and CMV. These assays need to be standardized to manage patients in different facilities. Five independent laboratories in Japan compared home‐brew assays and a prototype assay system to establish a standard quantitative procedure for measuring EBV and CMV. Reference standards and a total of 816 (642 EBV and 174 CMV) whole blood samples from post‐transplantation recipients were used for this multicenter evaluation. The prototype reference standard for EBV was compared to a panel of samples, with a theoretical expected value made using EBV‐positive cells containing two virus genome copies per cell. The mean ratio of the reference standard at each site to the standard of the prototype assay was ≤4.15 for EBV among three different sites and ≤3.0 for CMV between two laboratories. The mean of the theoretical expected number of the EBV genome: prototype reference was close to 1.0. The correlation coefficients between the viral copy numbers determined using the prototype assay and those using each home‐brew assay were high (EBV, 0.73–0.83, median = 0.78; CMV, 0.54–0.60, median = 0.57). The dynamics of the EBV and CMV loads in transplant recipients were similar between the assay types. There was an inter‐laboratory difference among the quantification results, indicating that a unified protocol and kit are favorable for standardizing the quantification of EBV and CMV. Such standardization will help to standardize the diagnosis and monitoring of diseases associated with EBV and CMV.  相似文献   
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This data paper reports tree census data collected in a network of 34 forest sites in Japan. This is the largest forest data set freely available in Japan to date. The network is a part of the Monitoring Sites 1000 Project launched by the Ministry of the Environment, Japan. It covers subarctic to subtropical climate zones and the four major forest types in Japan. Forty-two permanent plots, usually 1?ha in size, were established in old-growth or secondary natural forests. Censuses of woody species ??15?cm girth at breast height were conducted every year or once during 2004 to 2009. The data provide species abundance, survivorship and stem girth growth of 52,534 individuals of 334 tree and liana species. The censuses adopted common census protocol, which provide good opportunities for meta-analyses and comparative studies among forests. The data have been used for ecological studies as well as for the biodiversity reports published by the Ministry of the Environment.  相似文献   
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Summary Yeast cells were irradiated with monochromatic synchrotron radiation (SR) under wet conditions in the wavelength region from 160 to 185 nm at INS-SOR, Tokyo. By the particle-induced X-ray emission (PIXE) method applied to whole cells several elements were found to be released from the irradiated cells at the wavelengths shorter than 170 nm. The most drastic release occurred with phosphorus, followed potassium. Sulphur and calcium were not released over the whole wavelength region studied. It was also revealed that the release of these elements paralleled the cell inactivation. The cause of these element releases upon vaccuum-UV irradiation was inferred in relation to the dissociation of H2O molecules located in the vicinity of the cell surface region.  相似文献   
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We developed the real-time PCR quantification of endothelin-A (ET-A) and endothelin-B (ET-B) receptor genes and present their relative expression levels in various adult tissues and during development in mouse using the 2(-Delta Delta C(T)) method. ET-A and ET-B receptors were detected in all tissues examined. Gene expression of ET-A and ET-B receptors increases during the later stages of embryonic development in lung, heart, liver, kidney, and skin and reaches a maximum on the first one or two days after birth. The results, in agreement with our data on endothelin (ET) ligands, suggest that the ET system may be involved in the emergence and maintenance of functions vital after birth in these organs. These findings were corroborated through observation of the correlation between the gene expression and (poly)peptide production of the ET system in normal skin before and after parturition.  相似文献   
60.
Although peroxisome proliferator-activated receptor (PPAR)gamma agonists ameliorate insulin resistance, they sometimes cause body weight gain, and the effect of PPAR agonists on insulin secretion is unclear. We evaluated the effects of combination therapy with a PPARgamma agonist, pioglitazone, and a PPARalpha agonist, bezafibrate, and a dual agonist, KRP-297, for 4 wk in male C57BL/6J mice and db/db mice, and we investigated glucose-stimulated insulin secretion (GSIS) by in situ pancreatic perfusion. Body weight gain in db/db mice was less with KRP-297 treatment than with pioglitazone or pioglitazone + bezafibrate treatment. Plasma glucose, insulin, triglyceride, and nonesterified fatty acid levels were elevated in untreated db/db mice compared with untreated C57BL/6J mice, and these parameters were significantly ameliorated in the PPARgamma agonist-treated groups. Also, PPARgamma agonists ameliorated the diminished GSIS and insulin content, and they preserved insulin and GLUT2 staining in db/db mice. GSIS was further increased by PPARgamma and -alpha agonists. We conclude that combination therapy with PPARgamma and PPARalpha agonists may be more useful with respect to body weight and pancreatic GSIS in type 2 diabetes with obesity.  相似文献   
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