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151.
Justification of early treatment of nocturnal enuresis is founded in the negative psychological impact on the child. In fact nocturnal enuresis delays early autonomy and socialisation by decreasing in self-esteem and self-confidence. Nocturnal enuresis classification is the preliminary step to correct therapy. Enuresis must be classified as primary (never acquired nocturnal control) or secondary (at least 6 months of dry nights). A child is also classified as having monosymptomatic enuresis if she/he experienced only night wetting and symptomatic enuresis if she/he experienced night wetting associated with diurnal voiding symptoms (urinated > or = 7 times a day, urgency, damp pants, squatting, holding the perineum, sitting on one heel). Monosymptomatic patients must be treated with desmopressin nasal spray at the daily dose of 20 micrograms at bed time. If the reduction of at least the 50% of the basal number of the wet nights is not achieved, the dosage must be increased until 40 micrograms. For patients affected by rhinitis or asthma, desmopressin is now available in tablets. In symptomatic patients desmopressin therapy must be associated to oxybutinin (5 mg x 2). Therapy interruption must be gradual with desmopressin reduction of 10 micrograms every 30 days. In symptomatic patients oxybutinin must be introduced only at bed time. The efficacy of the drugs depends on the therapy length. The highest percentage of success is obtained if the treatment is protracted for at least six months. Antidepressants are also used for nocturnal enuresis especially imipramine. The dosage varies between 0.5-1.5 mg/ kg/daily. As plasmatic levels are achieved only in 30% of treated patients, a 3-5 fold increase in suggested. Nevertheless these levels result in near toxic threshold concentration. Sporadic treatment purposes include amytriptiline, diclofenac sodicum, viloxsazine and methilphenidate if giggle incontinence is present. Non responders may be treated with alarm. If after 16 weeks of treatment no success is obtained alarm use must be interrupted. 相似文献
152.
Intravascular adhesion of leucocytes plays a role in the pathogenesis of acute and chronic vascular disease. Regular aerobic exercise seems to protect against vascular disease. Since leucocyte adhesion is mediated by integrins, we tested the hypothesis that surface expression of the integrin adhesive receptors LFA-1 (cd11a/cd18), MAC-1 (cd11b/cd18), gp 150/95 (cd11c/cd18), and VLA-4 (cd29/cd49) is decreased by moderate endurance exercise. Surface expression of integrins was measured by FACS analysis in 19 healthy subjects (16 males, 3 females, 36.6 +/- 8.7 years, 177.1 +/- 7.5 cm, 70.3 +/- 8.1 kg) before and after submaximal exercise (3 h run) using monoclonal antibodies against cd11a, cd11b, cd11c, cd18, cd29 and cd49. In addition, we compared resting integrin expression in this group with a group of sedentary subjects (19 males, 6 females, 29.3 +/- 5.3 years). White blood cell count increased from 5300 ml(-1) to 9740 ml(-1) during exercise (P < 0.001). Nevertheless, the expression (indicated by the mean log fluorescence) of cd11a (94 +/- 24 vs. 78 +/- 14) and cd18 (128 +/- 31 vs. 102 +/- 21) on lymphocytes and of cd11a (104 +/- 25 vs. 85 +/- 16), cd11c (497 +/- 171 vs. 408 +/- 126) cd29 (109 +/- 16 vs. 89 +/- 16), cd49 (69 +/- 8 vs. 54 +/- 11) on monocytes was decreased after exercise (all P < 0.05). In contrast, integrin expression on granulocytes was not altered by exercise. Comparison of exercising and sedentary subjects showed a significantly decreased expression of integrins in exercising subjects. Our results demonstrate that moderate exercise leads to decreased expression of integrin receptors on leucocytes. This decreased expression of adhesion molecules may result in decreased adhesion and infiltration of leucocytes into the vessel wall. This phenomenon may play a role in the beneficial effect of moderate exercise in prevention of acute and chronic vascular disease. 相似文献
153.
SS Blair 《Canadian Metallurgical Quarterly》1997,7(11):R686-R690
Recent results show that in the developing Drosophila wing, the secreted pioneer protein Fringe regulates the sensitivity of the Notch signaling pathway to different ligands. This provides a likely mechanism by which Fringe-like molecules may control patterning in both Drosophila and vertebrates. 相似文献
154.
BACKGROUND: Steroid 5 alpha-reductase is implicated in the pathogenesis of benign prostatic hyperplasia (BPH). We studied the in vitro and in vivo effects of FR146687, a new inhibitor of 5 alpha-reductase. METHODS: Two isozymes of rat and human 5 alpha-reductases were expressed in 293 cells. In vivo effects of drugs were evaluated on rat and dog prostates. Castrated immature rats were injected with testosterone propionate (TP) or 5 alpha-dihydrotestosterone propionate (DHTP) to induce growth of the ventral prostates. Testosterone and 5 alpha-dihydrotestosterone (DHT) contents in rat and dog prostates were measured by gas chromatography-mass spectrophotometry (GC-MS). RESULTS: FR146687 showed noncompetitive inhibition in both isozymes and no inhibitory effects on other steroid oxidoreductases. In mature rats and castrated immature rats treated with TP, FR146687 dose-dependently reduced ventral prostate and seminal vesicle weight at doses above 0.1 mg/kg, while castrated immature rats treated with DHTP were not affected by FR146687. FR146687 showed more potent reduction of rat prostates than finasteride. DHT concentration in the prostates was significantly reduced when FR146687 was administered to rats and beagles. CONCLUSIONS: FR146687 is a dual inhibitor for 5 alpha-reductase isozymes and significantly reduced the growth and DHT content in the prostate. 相似文献
155.
156.
157.
Gregory KB Larese-Casanova P Parkin GF Scherer MM 《Environmental science & technology》2004,38(5):1408-1414
RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine), a nitramine explosive, is often found as a subsurface contaminant at military installations. Though biological transformations of RDX are often reported, abiotic studies in a defined medium are uncommon. The work reported here was initiated to investigate the transformation of RDX by ferrous iron (Fe(II)) associated with a mineral surface. RDX is transformed by Fe(II) in aqueous suspensions of magnetite (Fe3O4). Negligible transformation of RDX occurred when it was exposed to Fe(II) or magnetite alone. The sequential nitroso reduction products (MNX, DNX, and TNX) were observed as intermediates. NH4+, N2O, and HCHO were stable products of the transformation. Experiments with radiolabeled RDX indicate that 90% of the carbon end products remained in solution and that negligible mineralization occurred. Rates of RDX transformation measured for a range of initial Fe(II) concentrations and solution pH values indicate that greater amounts of adsorbed Fe(II) result in faster transformation rates. As pH increases, more Fe(II) adsorbs and k(obs) increases. The degradation of RDX by Fe(II)-magnetite suspensions indicates a possible remedial option that could be employed in natural and engineered environments where iron oxides are abundant and ferrous iron is present. 相似文献
158.
Kristopher Page Michael Wilson Nicola J. Mordan Wojciech Chrzanowski Jonathan Knowles Ivan P. Parkin 《Journal of Materials Science》2011,46(19):6355-6363
The adhesion of Staphylococcus aureus was studied using a selection of laboratory-prepared and commercially available coated glass substrates using a simple methodology.
Substrates were examined by scanning electron microscopy, atomic force microscopy and water droplet contact angles. It was
found that microbial adhesion was independent of surface roughness, when this was of a lower magnitude than microbial size.
It was also found that microbial adhesion was greater for hydrophilic surfaces than for hydrophobic ones, but that on a photoinduced
superhydrophilic surface, microbes were more spread out—a potential benefit for more effective photocatalytic disinfection.
It is suggested that hydrophobic and photoinduced superhydrophilic surface coatings both have potential as a means of reducing
microbial fouling of surfaces. 相似文献
159.
160.
N Nakashima DW Rose S Xiao K Egawa SS Martin T Haruta AR Saltiel JM Olefsky 《Canadian Metallurgical Quarterly》1999,274(5):3001-3008
Crk is a member of a family of adapter proteins predominantly composed of Src homology 2 and 3 domains, whose role in signaling pathways is presently unclear. Using an in situ electroporation system which permits the introduction of glutathione S-transferase (GST) fusion proteins into cells, we found that c-CrkII bound to p130(cas), but not to paxillin in serum-starved rat-1 fibroblasts overexpressing the human insulin receptor (HIRc cells) in vivo. 17 nM insulin stimulation dissociated the binding of c-CrkII to p130(cas), whereas 13 nM insulin-like growth factor-I, 16 nM epidermal growth factor (EGF), and 10% serum each showed little or no effect. We found that stress fiber formation is consistent with a change in the p130(cas).c-CrkII interactions before and after growth factor stimulation. Microinjection of either GST-Crk-SH2 or -Crk-(N)SH3 domains, or anti-Crk antibody each inhibited stress fiber formation before and after insulin-like growth factor-I, EGF, and serum stimulation. Insulin stimulation by itself caused stress fiber breakdown and there was no additive effect of microinjection. Microinjection of anti-p130(cas) antibody also blocked stress fiber formation in quiescent cells. Microinjection of the Crk-inhibitory reagents also inhibited DNA synthesis after insulin-like growth factor-I, EGF, and serum stimulation, but not after insulin. These data suggest that the complex containing p130(cas).c-CrkII may play a crucial role in actin cytoskeleton organization and in anchorage-dependent DNA synthesis. 相似文献