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151.
Melphalan and analogous aniline mustard derivatives were tested on antitumor activity in vitro. All compounds showed similar antiproliferative effects against melanoma B16, sarcoma 180 and leukemia P388D1. Thus, the singular clinical efficiency of melphalan may not simply be explained by a selective uptake employing amino acid carrier systems of tumor cells. 相似文献
152.
153.
C. Grüber S. Illi A. Plieth C. Sommerfeld U. Wahn 《Clinical and experimental allergy》2002,32(4):526-531
BACKGROUND: Turkish children have been found to suffer less from atopic diseases than their German peers. The underlying causes are unknown. OBJECTIVE: To evaluate rates of sensitization and atopic disease among children in Germany with German or Turkish ethnicity and different degrees of cultural adaptation. METHODS: This was a cross-sectional study. The setting was screening for school eligibility in an inner-city district of Berlin/Germany. The participants were preschool children born in Germany with double German or double Turkish parental citizenship. Cultural adaptation of Turkish children was assessed by the language parents used to communicate with their child: only Turkish (n = 60, group A); Turkish and German (n = 269, group B); and only German (n = 103, group C). Group D contained children from German parents (n = 383). The main outcome measures were specific sensitization to common aeroallergens (CAP-System, Pharmacia Phadiatop >or= 0.35 kU/L), and lifetime and 1-year prevalences of allergic disease symptoms (ISAAC questionnaire in German and Turkish, Mantel-Haenszel test for trend). RESULTS: Sensitization rates for groups A, B, C and D were 8.0%, 6.8%, 18.9% and 18.3%, respectively (P = 0.004). The corresponding prevalence rates for wheeze ever were 6.7%, 9.3%, 12.6% and 21.3% (P < 0.001), wheeze in the past year 3.3%, 3.7%, 9.7% and 10.2% (P = 0.001), itchy rash ever 3.3%, 6.3%, 8.7% and 13.7% (P < 0.001), itchy rash in the past year 1.7%, 3.7%, 4.9% and 9.5% (P < 0.001), respectively. No significant differences were found for hay fever symptoms. CONCLUSIONS: Higher cultural adaptation is correlated with higher rates of allergic sensitization and disease among children of Turkish origin living in Berlin. This correlation suggests that environmental rather than genetic differences are responsible for the differences observed. 相似文献
154.
We studied the role of theophylline on outcome of status epilepticus (SE) in children. During a two-year-period, 16 of 114 episodes of SE occurred in children receiving theophylline. At the onset of SE, theophylline blood levels were elevated in 8 episodes, and were therapeutic or subtherapeutic in 8 episodes. In the 8 episodes of SE with elevated theophylline levels, one child died and three suffered permanent new neurologic deficits. In the 8 episodes of SE with normal or low theophylline levels, only one child had a transient deficit. The occurrence of death or disability in 4 of 8 episodes of SE with elevated theophylline was considerably higher than the 23% incidence of death or persistent CNS deficit in the overall series of 114 episodes of SE. We conclude that theophylline, at toxic levels, is a significant factor in increased morbidity. We suspect that the hypoxia from the respiratory disorder for which theophylline was used, and the reduced cerebral blood flow known to occur with theophylline led to a failure to compensate for the increased cerebral metabolic rate of SE, thus increasing the risk of a poor outcome. 相似文献
155.
Brattleboro rats manifest chronic diabetes insipidus as a result of the genetic deficiency of hypothalamic vasopressin. When basal hypothalamic tissue derived from adult F344 rats was implanted as cell suspensions or tissue blocks in the supraoptic regions of these animals, concentration of urine together with reduced urine output and water intake was observed in some animals. Histologic examination of the grafted brains from the responding animals revealed neuronal cells at the implant sites and vasopressin-staining fibers in the median eminence. This study demonstrates the feasibility of the grafting of adult cerebral tissues to correct a genetic hormonal deficiency. 相似文献
156.
1. The hydrolysis of sugar alcohols of the disaccharide type such as lactitol, maltitol and Palatinit (the latter an equimolar mixture of 6-O-alpha-D-glucopyranoside-D-mannitol and 6-O-alpha-D-glucopyranoside-D-sorbitol) by homogenates of human intestinal biopsies were compared with corresponding natural disaccharides such as lactose, maltose and isomaltose. Seven of the human biopsies were normal with regard to their disaccharidase activities, while twelve biopsies showed decreased levels of disaccharidase activities. 2. All biopsies, normal as well as abnormal, showed essentially the same capacity to hydrolyse the sugar alcohols. Activities towards lactitol (0.34 IE/g protein (where IE = mumol disaccharide hydrolysed/min at 37 degrees)) and Palatinit (2.50 IE/g protein) were only 1.3% of those towards lactose and isomaltose. The activity towards maltitol was much higher (19.1 IE/g protein), approximately 10% of that towards maltose and about as high as the activity towards trehalose. This finding indicates that despite the fact that lactitol and Palatinit were poor substrates, significant amounts of ingested maltitol might be digested and utilized by man. 3. Glucose release was reduced by approximately 25% when maltitol or Palatinit were present at concentrations equal to those of maltose. Palatinit decreased the hydrolysis of sucrose by 12%. Lactitol had no inhibitory effect on the hydrolysis of disaccharides. 相似文献
157.
158.
Heparin or heparan sulfate--what is the difference? 总被引:3,自引:0,他引:3
159.
In a clinical series the accuracy of standard colloid scintigraphy and gray-scale ultrasonography in investigations for liver disease was evaluated. The results of 246 investigations in which both methods were utilized were reviewed and classified according to diagnosis and follow-up. In focal disease the sensitivity was 0.90 for scintigraphy, and 0.83 for ultrasonography; ultrasonography had the higher specificity, 0.94 compared with 0.77 for scintigraphy. In diffuse disease the sensitivity was found to be low for both methods, about 0.60, while specificity was high, 0.86 for scintigraphy and 0.92 for ultrasonography. Decreased liver function in diffuse liver disease as reflected by bone marrow uptake at scintigraphy was not found to have any influence on the degree of sensitivity of ultrasonography. 相似文献
160.