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91.
Current medical thinking supports early initiation of aggressive approaches to the management of perinatally acquired HIV infection. Biological mothers, however, may not endorse this way of managing their child's condition. For this study, grounded theory methods were used to conduct secondary analysis of eight semi-structured in-depth interviews with parents of children with perinatally acquired HIV. Biological mothers' perspectives on their children's treatment for perinatally acquired HIV infection, the strategies they used to manage their children's treatment and sociocultural influences on mothers' beliefs and actions are explored and described. Creation of a framework that may be useful for future research and recommendations for clinical practice are offered.  相似文献   
92.
Previous studies have shown that polycyclic aromatic hydrocarbons (PAHs) mobilize intracellular Ca2+ in human T cells by inositol trisphosphate-dependent mechanisms resulting from activation of phospholipase C-gamma by SRC-related protein tyrosine kinases, thereby mimicking antigen-receptor activation. Ca2+ appears to play an important second messenger role in growth factor control of cell proliferation in human mammary epithelial cells (HMEC), such as the epidermal growth factor receptor pathway. The purpose of the present studies was to determine if PAHs are able to increase intracellular Ca2+ in primary cultures of HMEC and increase cell proliferation. Two carcinogenic and two non-carcinogenic PAHs were tested for their ability to increase intracellular Ca2+ in HMEC. The carcinogenic PAHs dimethylbenz[a]anthracene (DMBA) and benzo[a] pyrene (BaP) were able to cause Ca2+ elevation in HMEC at early time points (2 h) and caused sustained alterations in Ca2+ homeostasis (18 h). DMBA showed maximal effects at early time points (2 h), while BaP showed maximal effects on sustained Ca2+ (18 h). 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), a potent dioxin and tumor promoter, produced maximal Ca2+ elevation at 2 h, with a return to near baseline levels by 6 h. The non-carcinogenic PAHs benzo[e]pyrene and anthracene did not significantly alter intracellular Ca2+ at any time point. alpha-Naphthoflavone significantly reduced the Ca2+ response induced by BaP treatment, but not by DMBA or TCDD, suggesting that P450 1A or 1B metabolism of BaP may be important in the sustained Ca2+ elevating response. In evaluating the effects of BaP on HMEC proliferation, BaP was found to increase the number of cells recovered after 4 days in culture in the absence or presence of various concentrations of epidermal growth factor. These studies provide initial evidence that Ca2+ signaling may be associated with mitogenesis in HMEC, which may play a role in tumor promotion and progression produced by PAHs.   相似文献   
93.
Three cases of asymptomatic intussusception in adults are reported, discovered incidentally during a CT scan of the abdomen. It is being increasingly observed in adults, possibly aided by the reformatting capabilities of the new multislice CT scanners. It has been documented in children where it is considered to be transient and of no clinical significance.  相似文献   
94.
Holoprosencephaly (HPE) is the most common brain anomaly in humans, involving abnormal formation and septation of the developing central nervous system. Among the heterogeneous causes of HPE, mutations in the Sonic Hedgehog (SHH) gene have been shown to result in an autosomal dominant form of the disorder. Here we describe a total of five different mutations in the processing domain encoded by exon 3 of SHH in familial and sporadic HPE. This is the first instance in humans where SHH mutations in the domain responsible for autocatalytic cleavage and cholesterol modification of the N-terminal signaling domain of the protein have been observed.   相似文献   
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In order to search for new compounds with higher anti-cancer activities and lower toxicities, 19 amino acid derivatives of norcantharidin, of which 16 are unknown compounds, were designed and synthesized. Preliminary screening results revealed that 2-(syn-exo-7-oxabicyclo [2. 2. 1] heptane-2, 3-dicarboxylic imido)-N-phenyl glutaramic acid exhibited a fairly apparent inhibitory activity against human-hepatoma cells in vitro (inhibitory rate 39.4% at 0.025 μtmol/ml).  相似文献   
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苦参碱的人体药代动力学   总被引:25,自引:0,他引:25  
建立了人血清苦参碱的高效液相色谱分析方法,此法回收率为99.1~102.2%,日内精密度RSD<4%,日间RSD<6%。血药浓度在1.25~40.0μg·mL-1范围内呈线性关系(r=0.9997)。8名健康志愿者iv苦参碱6ms·kg-1后,药代动力学过程符合二室模型。收集其中6名志愿者尿液,32h尿中原形药物排泄率为52.75%,肾清除率为143.79ml·min-1。  相似文献   
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