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91.
目的数值模拟抗血管生成因子Angiostatin和Endostatin对肿瘤血管生成的影响。方法建立肿瘤内外血管生成的二维离散数学模型。模型耦合两种抗血管生成因子Angiostatin和Endostatin的抑制效应,数值模拟在促血管生成因子诱导下肿瘤微血管网生成,讨论血管生成抑制因子的影响。结果抗血管生成因子Angiostatin对肿瘤内外血管网络生成的速度和成熟度有抑制作用。抗血管生成因子Angiostatin和Endostatin耦合作用时,在肿瘤血管生成的早期有明显的抑制效应;在肿瘤血管生成的中后期,它们可以降低肿瘤血管化程度。结论本文模型能够较好的模拟抗血管生成因子Angiostatin和Endostatin对内皮细胞迁移和增殖的抑制作用。  相似文献   
92.
LAW AND ETHICS     
Abstract

As society attempts to reduce sex stereotyping, it would be expected that male and female attitudes toward death would become similar. The purpose of this study was to measure various death-related attitudes of a group of adolescents and to determine if these attitudes remain sex related.

A sample of 152 seventh, eighth, and ninth-grade males (N = 71) and females (N = 81) from a Washington, D.C., metropolitan-area junior high school completed the Likert-type instrument. Using the chi-square statistic it was found that males and females differed significantly on 11 of the 22 items on the survey. Generally, females more than males, were in favor of abortion, valued funerals, and were more concerned with what might happen to their body subsequent to death. Differences were also found in attitudes about capital punishment and life after death. However, no significant male-female differences were found in fear of death.

It was concluded that differences in attitudes toward death generally are still consistent with traditional sex roles.  相似文献   
93.
The aim of this study was to investigate the effect of pre-irradiation with microwaves on the induction of radioadaptive response. In the 1st phase of the study, 110 male mice were divided into 8 groups. The animals in these groups were exposed/sham-exposed to microwave, low dose rate gamma or both for 5 days. On day six, the animals were exposed to a lethal dose (LD). In the 2nd phase, 30 male rats were divided into 2 groups of 15 animals. The 1st group received microwave exposure. The 2nd group (controls) received the same LD but there was no treatment before the LD. On day 5, all animals were whole-body irradiated with the LD. Statistically significant differences between the survival rate of the mice only exposed to lethal dose of gamma radiation before irradiation with a lethal dose of gamma radiation with those of the animals pre-exposed to either microwave (p=0.02), low dose rate gamma (p=0.001) or both of these physical adapting doses (p=0.003) were observed. Likewise, a statistically significant difference between survival rates of the rats in control and test groups was observed. Altogether, these experiments showed that exposure to microwave radiation may induce a significant survival adaptive response.  相似文献   
94.
Background Pityriasis rubra pilaris (PRP) is a rare inflammatory dermatosis with frequent clinical presentation as erythroderma. Conventional systemic treatment is often unsatisfactory and limited by long‐term toxicity. The use of tumour necrosis factor (TNF) antagonists has been reported previously in single cases, but lacking long‐term follow‐up or comparison between different biological agents. Objectives To assess the long‐term efficacy and safety of TNF‐alpha antagonist, infliximab and etanercept, either in monotherapy or in combination therapy of severe, refractory adult‐onset PRP. Methods Seven patients of adult‐onset PRP, six newly diagnosed type‐I and 1 type‐II, which were resistant or ineligible to conventional systemic treatment, received a single course of infliximab or etanercept therapy, alone or in combination with low‐dose acitretin (>0.25 mg/kg/daily). After complete remission and treatment discontinuation, a follow‐up period of 12 months was evaluated for relapses. Results Six patients obtained complete remission after a single course of anti‐TNF‐alpha therapy: mean therapy duration was 19.3 weeks (range 6–48 weeks). All patients obtained significant clearing (>75% of body surface area) of skin lesions at week 12. Two patients with marked keratoderma developed localized disease recurrence during treatment. During follow‐up, only a single patient, affected by type II PRP, had disease relapse. Conclusions Both TNF‐alpha antagonists proved successful for the treatment of refractory, adult‐onset PRP, yielding complete and persistent clinical responses in type‐I PRP. Infliximab was associated with a more rapid onset of action, while treatment duration was comparable with etanercept. PRP type II warranted long‐term therapy and showed relapse after drug discontinuation.  相似文献   
95.
BACKGROUND: Research on intellectual and cognitive functioning of children of alcoholics has been marked by inconsistency, with some studies unable to document deficits. This discrepancy may reflect the substantial heterogeneity found in the alcoholic population and among families of alcoholics. The current study sought to examine the effects of familial alcoholism subtypes on intellectual, cognitive, and academic performance in early school-aged sons of alcoholics. METHODS: Subjects for the present study were 198 elementary-age boys who were participants in the larger MSU-UM Longitudinal Study. Familial alcoholism subtypes were determined based on fathers' alcoholism and antisocial personality disorder diagnoses. Intellectual functioning was measured with the Wechsler Intelligence Scale for Children-Revised (WISC-R); academic achievement was measured with the Wide Range Achievement Test-Revised. In addition, Mazes and Freedom from Distractability factor scores of the WISC-R were used to assess abstract planning and attention abilities. RESULTS: Children of antisocial alcoholics (AALs) displayed the worst IQ and academic achievement compared with children of nonantisocial alcoholics (NAALs) and controls. In addition, children of AALs displayed relatively poorer abstract planning and attention abilities compared with children from control families. Regression analyses revealed that familial alcoholism subtype continued to account for variance in child intellectual ability even when other factors were excluded. CONCLUSIONS: Findings indicate that children from AAL families are most susceptible to relative intellectual, cognitive, and academic deficits. The study further supports the proposition that familial risk characteristics (i.e., paternal alcoholism and antisociality) may serve as effective indicators of family risk for poor intellectual outcome among offspring as early as the elementary school years.  相似文献   
96.
We report a clinical trial with carboplatin (CBDCA) in 15 children with malignant solid tumors recurrent after or resistant to conventional treatment. Based on previous phase I clinical trials, these children were given a dose of CBDCA 560 mg/m2 by intravenous infusion every 4 weeks. The study includes a pharmacokinetic analysis of CBDCA in three patients. This clinical trial shows the feasibility of this CB-DCA schedule, even after high cumulative doses of previous chemotherapy. As expected the main toxicity was hematologic but the risk of renal and ototoxicity is not excluded and these functions have still to be monitored when this relatively high dose of CBDCA chemotherapy is used.  相似文献   
97.
The "truth" campaign was created to change youth attitudes about tobacco and to reduce teen tobacco use throughout Florida by using youth-driven advertising, public relations, and advocacy. Results of the campaign include a 92 percent brand awareness rate among teens, a 15 percent rise in teens who agree with key attitudinal statements about smoking, a 19.4 percent decline in smoking among middle school students, and a 8.0 percent decline among high school students. States committed to results-oriented youth anti-tobacco campaigns should look to Florida's "truth" campaign as a model that effectively places youth at the helm of anti-tobacco efforts.  相似文献   
98.
OBJECTIVE: The purpose of this study was to investigate long-term outcome and prognosis in a bulimic and subthreshold bulimic sample. METHOD: In a follow-up study, 44 patients diagnosed with bulimia nervosa and subthreshold bulimia nervosa were contacted after an average follow-up period of 9 years. RESULTS: Results revealed that 72.7% (n = 32) of the participants were recovered at the time of follow-up. An investigation of prognostic variables showed that good outcome was associated with a shorter duration of illness, which was defined as the time between onset of symptoms and first treatment intervention. If participants were initially treated within the first few years of the illness, the probability of recovery was above 80%. However, if they were initially treated 15 years or more after the onset of the illness, the probability of recovery fell below 20%. DISCUSSION: This finding suggests that early identification of bulimia nervosa may be a very important factor in preventing a chronic eating disorder.  相似文献   
99.
Growth and endocrine disorders in optic glioma   总被引:2,自引:0,他引:2  
Hypothalamo-pituitary function in children with optic glioma may be impaired by the tumour itself and by the high cranial radiation doses used in treatment. This study evaluates the effect of optic glioma and its treatment on patient growth and pubertal development. Twenty-one patients (13 boys, 8 girls), treated for optic glioma by cranial irradiation (45–55 Grays) at a mean age of 5.4 years, were evaluated before (n=10) and/or after (n=21) irradiation. Growth hormone (GH) deficiency was present in only 1 patient tested before irradiation and in all patients after irradiation. Precocious puberty occurred in 7/21 cases, before irradiation in 5 patients and after irradiation in 2 patients. The cumulative height loss during the 2 years after irradiation was 0.2±0.2 SD (m±SEM) in 7 patients with precocious puberty and 1.1±0.2 SD in 14 prepubertal patients (P<0.01). The corresponding bone age advance over chronological age, evaluated 1–3 years after irradiation, was 1.1±0.5 and –0.7±0.3 year in the two groups (P<0.01). The mean height loss between time of irradiation and the final height was 2.3±0.6 SD (n=6). Primary amenorrhoea, associated with low oestradiol levels, occurred in two of the three girls of pubertal age. These data indicate that the high dose of cranial radiation used to treat optic glioma invariably results in GH deficiency within 2 years and that hGH therapy is required when GH deficiency is documented. Precocious puberty, resulting in apparently normal growth velocity in spite of GH deficiency, should be treated with luteinizing hormone-releasing hormone analogues because of the risk of accelerated bone maturation and reduced final height.  相似文献   
100.
A complete family history was obtained for 501 patients with Wilms' tumor, treated in departments of pediatric oncology in whole France. The information was collected by self-questionnaire and/or by interview of parents. The proportion of bilateral cases is 4.6% and there are 12 patients (2.4%) with a positive family history of Wilms' tumor. The affected relatives are most often distant and no first degree relative was affected. Apart from the well-known associations with aniridia, hemihypertrophy, genitourinary anomalies, Beckwith-Wiedeemann, and Drash syndromes, there is also a significant excess of congenital heart defects (P = .008) which remains to be explained. Several findings support the bimutational hypothesis such as earlier diagnosis and increased parental age in bilateral cases. No particular anomalies and no increased frequency of childhood cancer were found in patients' relatives. The frequency of Wilms' tumor in relatives was estimated to be less than 0.4% in sibs, 0.06% in unclesand aunts, and 0.04% in first cousins. These figures are very different from those found in retinoblastoma and suggest that the mechanism may be more complex in Wilms' tumor. This conclusion is in agreement with molecular biology studies in tumors and linkage analysis in multiple case families which suggest that more than one locus is involved. © 1992 Wiley-Liss, Inc.  相似文献   
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