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排序方式: 共有436条查询结果,搜索用时 15 毫秒
1.
Mary ER O'Brien Janet Hardy Sylvia Tan Jackie Walling Brian Peters Sarah Hatty Eve Wiltshaw 《Cancer chemotherapy and pharmacology》1992,30(3):245-248
Summary A total of 16 patients with recurrent epithelial ovarian cancer were treated with sulofenur (LY 186641), a novel oral sulfonylurea. All subjects had received previous chemotherapy. Anaemia occurred in all 16 patients, 14 of whom required a blood transfusion, and 2/16 patients received methylene blue for breathlessness due to methaemaglobinaemia. Treatment was discontinued in 2/16 cases due to rising liver enzyme values, which reverted to normal on cessation of the drug. There was no nausea or alopecia. Only two minor responses were seen. Plasma drug levels were insufficient to result in antitumour activity as extrapolated from animal data. Further studies that attempt to increase the bioavailability and improve the therapeutic index are warranted. 相似文献
2.
Expression of the large T protein of polyoma virus promotes the establishment in culture of "normal" rodent fibroblast cell lines. 总被引:80,自引:14,他引:66 下载免费PDF全文
M Rassoulzadegan Z Naghashfar A Cowie A Carr M Grisoni R Kamen F Cuzin 《Proceedings of the National Academy of Sciences of the United States of America》1983,80(14):4354-4358
Transfer into mouse and rat embryo fibroblasts in primary culture of cloned polyoma virus genes encoding only the large T protein led to the establishment of flat colonies in sparse subcultures at a frequency equal to that of transformation by wild-type virus. Cell lines could be derived from such colonies and maintained in culture for large numbers of generations without entering crisis. They exhibited a normal phenotype, by the criteria of growth on plastic to a low saturation density and of anchorage dependency. However, they required a lower serum concentration for growth than spontaneously established 3T3 cells. Similar results were obtained after transfer of recombinant DNA molecules encoding only the amino-terminal 40% of the large T protein, suggesting that this "immortalization" function corresponds to the activity of an amino-terminal domain of the protein. Immunoprecipitation analysis of T antigens in cell lines established after transfer of the full-size and of the truncated large T genes demonstrated the expression of the full-size large T protein and of a Mr 40,000 antigen expressed from the amino-terminal part of the gene, respectively. After transfer of a "large T only" plasmid that carries a tsa mutation, cell lines were established at 33 degrees C with the same efficiency as with the wild-type large T gene, but their growth was arrested after a shift to 40 degrees C, with a progressive loss in cell viability. This result indicates a continuous requirement for a large T function in the maintenance of "immortality." 相似文献
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Increased circulating CSF-1 (M-CSF) in myeloproliferative disease: association with myeloid metaplasia and peripheral bone marrow extension 总被引:3,自引:1,他引:3
Myeloproliferative disease (MPD) is heterogeneous in phenotypic expression and may display features consistent with expansion and activation of the monocyte/macrophage population during its course. The role of colony-stimulating factor-1 (CSF-1) in the pathophysiology of MPD was investigated by measuring circulating CSF-1 levels and examining their relationship to disease phenotype. Serum CSF-1 concentrations, measured by radioimmunoassay, were elevated in all MPD phenotypes. CSF-1 levels differed significantly between groups of patients with essential thrombocythemia, polycythemia vera, and postpolycythemic or agnogenic myeloid metaplasia (in ascending order). CSF-1 serum levels were positively correlated with spleen size and the degree of peripheral bone marrow extension, determined by scintigraphy using a macrophage-seeking isotope. There was no correlation between CSF-1 concentration and circulating levels of erythrocytes, neutrophils or platelets, or the presence of bone marrow fibrosis. Elevated serum CSF-1 levels appear to be associated with an expanded monocyte/macrophage population in MPD. In view of the known cooperativity between CSF-1 and other growth factors in regulating hematopoiesis, the finding of increased serum CSF-1 concentrations and its association with myeloid metaplasia and bone marrow extension may indicate a pathophysiologic role for CSF-1 in determining the phenotypic expression of MPD. 相似文献
5.
目的:探讨皮质醇增多症的临床表现和内分泌检查等辅助检查的意义.方法:从年龄、性别、病程及实验室检查等方面,观察22例不同原因所致皮质醇增多症患者不同的临床表现和测定实验室检查指标.结果:22例中诊断库欣病(增生型)14例[63.6%,其中13例(92.9%)得到MRI检查证实],肾上腺腺瘤6例[27.3%,均得到MRI检查证实(100%)],另有肾上腺结节样增生1例(4.5%),异位ACTH综合征1例(4.5%).临床表现:按出现的频率前4位依次为,库欣病:高血压(100%)、满月脸(92.9%)、向心性肥胖(85.7%)、多血质(85.7%),肾上腺腺瘤:高血压(100%)、满月脸(100%)、向心性肥胖(100%)、多血质(83.3%).实验室检查:小剂量地塞米松不能抑制:库欣病与肾上腺腺瘤均为100%.结论:根据高血压、满月脸、向心性肥胖,小剂量地塞米松抑制试验和MRI检查可诊断绝大多数皮质醇增多症. 相似文献
6.
A. H. V. Schapira P. Barone R. A. Hauser Y. Mizuno O. Rascol M. Busse C. Debieuvre M. Fraessdorf W. Poewe for the Pramipexole ER Studies Group 《European journal of neurology》2013,20(1):50-56
Background and purpose: In chronic diseases including Parkinson’s disease (PD), complex pharmacotherapy dosing schedules are reported to reduce adherence, perhaps leading to less‐effective symptom control and, in PD, more erratic stimulation of dopamine receptors. However, blinded clinical‐trial designs preclude direct comparisons of adherence to various schedules. Methods: In two double‐blind (DB) studies of early PD and one of advanced PD, subjects received three‐times‐daily (t.i.d.) pramipexole or placebo. In open‐label (OL) extensions, subjects took extended‐release, once‐daily (q.d.) pramipexole. At 24 or 32 OL weeks, q.d. versus t.i.d. dosing preference was surveyed by questionnaire. Results: Of 590 DB‐trial completers with early PD, 511 entered the OL extension. Of 374 survey respondents, 94.4% preferred q.d. dosing (72.2% of them found it ‘very much more convenient’ and 27.8%‘more convenient’), 2.7% preferred t.i.d., and 2.9% chose ‘no difference’. Of 465 DB‐trial completers with advanced PD, 391 entered its OL extension. Of 334 survey respondents, 88.9% preferred q.d. dosing (59.9% of them found it ‘very much more convenient’ and 40.1%‘more convenient’), 5.7% preferred t.i.d., and 5.4% chose ‘no difference’. Results excluding DB‐placebo recipients were highly similar. Conclusions: In this first direct comparison of patient preference for q.d. versus t.i.d. dopamine‐agonist dosing, patients with early or advanced PD had a strong preference for q.d. rather than t.i.d. pramipexole. The high proportion of advanced‐PD patients declaring this preference indicates that it does not depend on whether a patient is taking concomitant PD medications dosed more frequently than q.d. 相似文献
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Comparison of the subacute toxicity and efficacy of 3-hydroxypyridin-4- one iron chelators in overloaded and nonoverloaded mice 总被引:3,自引:1,他引:3
Five orally effective iron chelators of the 3-hydroxypyridin-4-one series have been administered intraperitoneally to iron-overloaded and nonoverloaded male mice at a dose of 200 mg/kg/24 h for a total of 60 days to investigate the effect on iron loading and toxicity. There was a significant reduction in hepatic iron at the end of the study in the iron-overloaded mice with all compounds studied using chemical iron quantitation (P less than .001) and with Perls' stain (P less than .01). Liver iron removal with the hydroxypyridinones ranged from 37% with CP20 to 63% with CP51, compared with 46% removal for desferrioxamine (DFO). There was no significant reduction in splenic or cardiac iron with any chelator. There were no deaths in iron-overloaded animals receiving any of the hydroxypyridin-4-ones, but significantly more deaths in the nonoverloaded groups as a whole (P less than .03). No weight loss was observed with any chelator. Significant reductions in hemoglobin and white cell count were observed with CP20(L1). No histologic abnormalities of kidney, spleen, bone marrow, or stifle joints were observed. Intracytoplasmic inclusion bodies were observed in the centrilobular hepatocytes of animals administered each of the hydroxypyridin-4-ones, while the DFO-treated and control groups showed no such changes. 相似文献
9.
Aaron A Phillips Darren ER Warburton Philip N Ainslie Andrei V Krassioukov 《Journal of cerebral blood flow and metabolism》2014,34(5):794-801
Individuals with high-level spinal cord injury (SCI) experience low blood pressure (BP) and cognitive impairments. Such dysfunction may be mediated in part by impaired neurovascular coupling (NVC) (i.e., cerebral blood flow responses to neurologic demand). Ten individuals with SCI >T6 spinal segment, and 10 age- and sex-matched controls were assessed for beat-by-beat BP, as well as middle and posterior cerebral artery blood flow velocity (MCAv, PCAv) in response to a NVC test. Tests were repeated in SCI after 10 mg midodrine (alpha1-agonist). Verbal fluency was measured before and after midodrine in SCI, and in the control group as an index of cognitive function. At rest, mean BP was lower in SCI (70±10 versus 92±14 mm Hg; P<0.05); however, PCAv conductance was higher (0.56±0.13 versus 0.39±0.15 cm/second/mm Hg; P<0.05). Controls exhibited a 20% increase in PCAv during cognition; however, the response in SCI was completely absent (P<0.01). When BP was increased with midodrine, NVC was improved 70% in SCI, which was reflected by a 13% improved cognitive function (P<0.05). Improvements in BP were related to improved cognitive function in those with SCI (r2=0.52; P<0.05). Impaired NVC, secondary to low BP, may partially mediate reduced cognitive function in individuals with high-level SCI. 相似文献
10.
We report on a newborn girl with cystic adenomatoid malformation of the lungs supplied by an aberrant artery arising from the aorta at the level of the diaphragm. To the best of our knowledge, it is the first case diagnosed by prenatal ultrasound in which an arterial digital subtraction angiography (DSA) after birth showed the aberrant vessel. 相似文献