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51.
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One of the most exciting developments in pediatric dermatology has been the use of the flashlamp-pumped, 585-nm, pulsed dye laser for treatment of vascular birthmarks. In many cases the results are miraculous. The increase in self-esteem and happiness of many children and adolescents has been overwhelming; for some, depression has been lifted, stuttering has ceased, social involvement has increased, and antidepressants have been discontinued. There are many success stories to tell.
Despite the remarkable effects of the pulsed dye laser and the medical and psychosocial indications for its use, the issue of pain control remains significant. We have no perfect outpatient pediatric anesthetic. Most methods carry either some risk or, if not hazardous, often are not very effective for controlling pain. Needless to say, a diversity of opinions exist on how to manage discomfort from this treatment modality. Therefore, we thought it would be useful to share the experiences and opinions of several dermatologists who have extensive experience with the pulsed dye laser.  相似文献   
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The phosphorylation patterns of isolated red blood cell (RBC) membranes labeled with [ γ-32p]ATP are altered by Zn++ ions. Zn++ ions caused an increased phosphate incorporation into a 72 KDa protein and several proteins in the 40–60 KDa region and a decrease in the labeling of a 53 KDa protein. The 72 KDa and 53 KDa proteins have been identified as protein 4.2 and a protease-cleaved fragment of protein 3, respectively. Evidence suggests that the changes in phosphorylation pattern may be due to the stimulation of endogenous membrane alkaline phosphatase(s). Our results suggest that Zn++, at physiological concentrations in the intact erythrocyte, could modulate the phosphorylation of selected proteins which may regulate their association in the cytoskeletal network.  相似文献   
54.
It is generally accepted that the lung uptake of 67Ga in patients with pneumocystis carinii pneumonia (PCP) is diffuse and bilateral. Three cases of focal lung uptake of 67Ga in AIDS patients with PCP but without other opportunistic infection are described. While focal lung uptake is characteristic of opportunistic infections other than PCP, we wish to emphasize that focal uptake of gallium in the chest does not rule out PCP and may represent its earliest stage of presentation.  相似文献   
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Coronary angioplasty is unsuccessful in <3–5% of cases because the balloon catheter fails to follow a guidewire that has traversed a lesion. Between June 1986 and August 1987, 31 lesions were unable to be crossed with at least two standard angioplasty catheters. Finally, a 2.0-mm-diameter Hartzler LPS (ACS) was utilized and successfully crossed and dilated 16 out of 31 lesions (52%). In the remaining 15 lesions, the ProbeTM (USCI) 2.0 mm diameter × 1.5 cm long balloon wire was able to cross the lesions in 13 (82%) and successfully dilated 12. In one case, lesion rigidity prevented the balloon from expanding at 14 atm. A right coronary artery lesion was attempted in 11 cases, and a left anterior descending and circumflex artery lesion in two patients each. No complications were encountered. In seven out of 12 successful ProbeTM cases, a larger balloon catheter was used to further dilate the artery. This new balloon wire has increased our success rate in severe stenoses and in tortuous vessels with severe distal lesions, in which presently available angioplasty equipment has failed.  相似文献   
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Stimulation of the porcine immune system causes increased replication of porcine circovirus 2 (PCV2) in vivo. In the present study, we investigated whether various cytokines (interleukin-1 [IL-1], IL-6, IL-10, tumor necrosis factor-alpha [TNF-alpha], interferon-alpha [IFN-alpha], and IFN-gamma) are able to influence PCV2 infection in vitro. No changes were observed in IL-1, IL-6, TNF-alpha, or IL-10-treated cells. However, it was demonstrated that IFN- alpha and IFN-gamma influenced PCV2 infection in porcine kidney cells (PK-15) and porcine monocytic cells (3D4/31). IFN-gamma added to the culture medium before, during, or after inoculation increased the number of PCV2 antigen- positive cells, respectively, by 418%, 171%, and 691% in PK-15 cells and by 706%, 114%, and 423% in 3D4/31 cells. IFN-alpha pretreatment decreased the number of infected PK-15 cells. When it was added after inoculation, IFN-alpha enhanced PCV2 infection by 529% in PK-15 cells and by 308% in 3D4/31 cells. The effect of both IFNs on PCV2 infection was dose dependent and could be blocked with IFN-alpha or IFN-gamma neutralizing antibodies. Leukocyte-derived porcine IFN-gamma induced a similar effect on PCV2 infection. Treatment of PK- 15 cultures with IFN-gamma caused a 20 times higher production of progeny virus. Confocal microscopy studies showed that the enhancing effect of IFN-gamma on PCV2 infection was achieved by increased internalization of PCV2 virionlike particles (VLPs). Binding of the VLPs to the cell or expression kinetics of PCV2 proteins in infected cells were not altered by IFN-gamma treatment. To our knowledge, this study reports the first enhancement of a viral infection by treatment with type I or type II IFNs.  相似文献   
59.
Zusammenfassung Hintergrund: Die Assoziation zwischen Helicobacter-pylori-(H.-pylori-)Infektion und Dyspepsie wird kontrovers diskutiert. Im Rahmen der BASF-H.-pylori-Vorsorgeaktion wurde u. a. die Prävalenz von Dyspepsie bei arbeitsfähigen Personen ermittelt sowie der Zusammenhang mit der H.-pylori-Infektion und der Erfolg einer Eradikationstherapie untersucht. Probanden und Methodik: 6 132 Beschäftigte der BASF wurden untersucht und im Rahmen einer standardisierten Anamnese u. a. zu dyspeptischen Beschwerden befragt. Diese wurden entsprechend der führenden Symptomatik den Dyspepsiesubtypen vom Ulkustyp, Dysmotilitätstyp, Refluxtyp und unspezifischen Typ zugeordnet. Bei allen Beschäftigten wurde die Seroprävalenz (IgG-ELISA) der H.-pylori-Infektion bestimmt. Allen H.-pylori-positiven Personen mit Dyspepsie wurde weitere Diagnostik in Form einer Ösophagogastroduodenoskopie und einer Sonographie des Abdomens bei Fachärzten empfohlen und eine H.-pylori-Eradikationstherapie (Italian-Triple-Therapie) angeboten. In einer Untergruppe endoskopisch untersuchter Beschäftigter mit peptischer Ulkuskrankheit (PUD, n = 37) bzw. Non-Ulcer-Dyspepsie (NUD; n = 39) wurde der prognostische Wert der im Western Blot ermittelten Antikörper gegen CagA und VacA untersucht. Ergebnisse: 1 255 der 6 143 Beschäftigten (20,4%) berichteten über Dyspepsie. 492 Personen mit Dyspepsie (39,2%) waren gleichzeitig H.-pylori-positiv. Bei Personen ohne dyspeptische Symptome betrug die H.-pylori-Prävalenz 35,8%. Personen mit unterschiedlichen Dyspepsiesubtypen unterschieden sich nicht hinsichtlich der H.-pylori-Prävalenz. Personen, die häufige und intensive dyspeptische Beschwerden angaben, waren allerdings signifikant häufiger H.-pylori-positiv (OR 2,09, CI 1,43-3,05). Die Seroprävalenz von CagA und VacA bei Personen mit PUD unterschied sich nicht signifikant von derjenigen bei Personen mit NUD. 458 H.-pylori-positiven Personen wurde die Eradikation empfohlen. 330 Personen (72,1%) folgten der Empfehlung. 128 (27,9%) ließen sich nicht behandeln. An der Nachkontrolle nach 12 Monaten nahmen 402 Personen (87,8%) teil, davon waren 300 behandelt, 102 nicht. Der serologisch analysierte Eradikationserfolg lag bei 81,5%. 42,8% der erfolgreich behandelten Personen berichteten über Besserung ihrer Beschwerden, 33,2% über Beschwerdefreiheit. Bei den nicht behandelten Personen war dies nur in 16,7% bzw. in 37,3% der Fall. Vermehrte Refluxbeschwerden traten nach erfolgreicher Eradikation nicht auf. Schlussfolgerung: Wir konnten keinen generellen Zusammenhang zwischen Dyspepsie und H.-pylori-Infektion in einem großen Kollektiv arbeitsfähiger Personen erkennen. Häufige und intensive dyspeptische Symptome scheinen allerdings ein prädikativer Faktor für die H.-pylori-Seropositivität zu sein. Die serologisch bestimmbaren Virulenzfaktoren tragen nicht zur Unterscheidung PUD oder NUD bei. Die Eradikationstherapie führte nach 1 Jahr zwar häufiger zur Besserung, aber nicht häufiger zu Beschwerdefreiheit bei Beschäftigten mit dyspeptischen Beschwerden im Vergleich zu unbehandelten Personen. Abstract Background: The role of Helicobacter pylori (H. pylori) infection in dyspepsia is controversial. In the course of a health initiative within a large industrial corporation, we investigated the prevalence of both dyspepsia and positive H. pylori serology and the outcome of eradication therapy in symptomatic H. pylori positive employees. Test Persons and Methods: H. pylori serology (IgG ELISA) was determined in 6,143 employees of BASF AG Ludwigshafen/Germany who were also asked to complete a standardized health history administered by a physician. Peptic ulcer disease (PUD) and dyspepsia subgroups were defined based on past medical history and symptom profiles using the criteria of Heading. Upper GI endoscopy, abdominal ultrasound and eradication therapy (Italian Triple Therapy) was recommended for symptomatic H. pylori positive individuals. The prognostic value of antibodies against CagA and VacA was evaluated in 37 and 39 employees with PUD and non-ulcer dyspepsia (NUD) confirmed by endoscopy, respectively. Results: Of 6,143 employees, 1,255 (20.4%) were classified as dyspeptic, 492 (39.2%) of whom were H. pylori positive. The seroprevalence of H. pylori in asymptomatic employees was 35.8%. There were no significant differences in H. pylori seroprevalence among dyspepsia subgroups (reflux only, dysmotility only, reflux/dysmotility, ulcer-like and non-specific). However, individuals reporting severe dyspeptic symptoms were significantly more likely to be H. pylori positive (OR 2.09, CI 1.43-3.05). The seroprevalence of CagA and VacA was not significantly different among employees with NUD compared to referents or among employees with NUD compared to those with PUD. 330 (72%) of 458 employees with dyspepsia received eradication therapy, 128 persons refused therapy. Based on a 12-month follow-up of 402 individuals (300 of whom had received therapy), eradication success was 81.5% as judged by serology. Of the successfully treated employees, 33.2% reported a total absence and 42.8% reported a decrease in symptoms. Among the employees who refused therapy, the corresponding percentages were 37.3% and 16.7%, respectively. An increase in reflux complaints was not observed among treated employees. Conclusion: In a large active employee population, at most a very weak association was observed between the prevalence of H. pylori seropositivity and dyspepsia. Frequent and severe dyspeptic symptoms were associated with an increased rate of H. pylori seropositivity. The analysis of the virulence factors is not particularly helpful in discriminating PUD or NUD. Eradication of H. pylori infection leads to a decrease in dyspeptic symptoms after 12 months, but not more often to their complete absence compared to untreated individuals.  相似文献   
60.
This study describes ultrastructural changes in the pigmented hooded Lister rat retina, 3–12 months following X-irradiation with single doses of between 200 and 2000 cGy. The extreme radiosensitivity of the photoreceptor cells was underlined by the continued manifestation of fine structural changes and cell death up to 6 months post-radiation in animals receiving doses above 500 cGy. The retinal pigment epithelial (RPE) cells were more radioresistant than photoreceptors and RPE cell loss was only observed at doses of more than 1500 cGy. One year after irradiation with 1500 cGy the retinal vasculature showed capillary occlusion with some evidence of recanalisation. Telangiectasia was observed in the large retinal veins. Although the inner retinal neurones and glia1 cells showed no evidence of direct radiation damage, the nerve fibre layer adjacent to occluded retinal vessels demonstrated ultrastructural evidence of ischaemic neuropathy and retinal oedema. At doses above 1500 cGy the choriocapillaris showed platelet aggregation and capillary loss.  相似文献   
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