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BACKGROUND: Repairing dorsal nasal defects is a frequent challenge for dermatologic surgeons, mainly due to the high frequency of basal cell carcinomas on this site. Obvious scars, mismatched skin and distortion of the nasal contour are the surgical hazards that must be avoided in these cases. AIM: Our aim was to perform surgery involving a simple flap in order to repair medium to large defects on the dorsal side of the nose. METHODS: The dorsal horizontal advancement flap was studied in 12 patients, in order to evaluate the benefits and limits of this surgical procedure. RESULTS: The resulting scars on most of our patients were well-camouflaged among their natural skin lines, and there was neither distortion of the alar contour nor the nostril. CONCLUSIONS: This flap is easy to perform and, in selected cases, provides an outstanding alternative to second-intention healing, full-thickness skin grafts, transposition, rotation and pedicle flaps.  相似文献   
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Dermoids of the posterior cranial fossa in children are rare. We report the clinical and pathological data on nine children with these lesions. A mean follow-up of 17.3 years after total removal confirms the excellent prognosis irrespective of whether the presenting symptom is meningitis or intracranial hypertension. A brief review of 39 published cases follows.  相似文献   
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BACKGROUND: Nitric oxide (NO) plays a key role in wound repair and S-nitrosothiols like S-nitrosoglutathione (GSNO) are well known NO donors. METHODS: Animals were separated in two groups and submitted to excisional wounds on the dorsal surface at the first day. GSNO (100 microm)-containing hydrogels were topically applied on the wound bed in the GSNO group, daily, during the first 4 days. Control group was topically treated with hydrogel without GSNO for the same period. Wound contraction and re-epithelialization were measured. Animals were sacrificed 21 days after wounding. Samples of lesion and normal tissue were formalin-fixed, paraffin embedded for histological analysis. RESULTS: Wound contraction, measured 14 and 21 days after wounding, was greater in the GSNO group than in the control group (P<0.05 for both). The re-epithelialized wound area, measured 14 days after wounding, was higher in the GSNO group than in the control group (P<0.05). A higher amount of inflammatory cells was observed in superficial and deep areas of the granulation tissue of the control group compared to the GSNO group. Twenty-one days after wounding, thin red-yellow collagen fibers arranged perpendicularly to the surface were found in the granulation tissue of the control group, whereas in the GSNO-treated group collagen fibers were thicker and arranged parallel to the surface. Increased number of mast cells was observed in the GSNO group compared with that in the control group. Vascularization and myofibroblast distribution were similar in both groups. CONCLUSION: Topical application of GSNO-containing hydrogel during the early phases of rat cutaneous wound repair accelerates wound closure and re-epithelialization and affects granulation tissue organization.  相似文献   
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Intracerebral vascular reactivity induced by the nitric oxide (NO) donor isosorbide dinitrate (IDN, 5 mg sublingually) is more major and longer-lasting in migraine patients who develop delayed headache in response to the drug. The headache is purportedly due to neuronally-mediated vascular mechanisms. Indomethacin inhibits prostaglandin synthesis, which is involved in NO generation. Indomethacin also decreases cerebral blood flow by constricting precapillary resistance vessels. In the present study, the hemodynamic effects of indomethacin were evaluated in migraine patients and healthy controls by means of transcranial Doppler monitoring. Indomethacin caused a significant decrease in mean flow velocity in the middle cerebral artery. This was an additional effect to the mean velocity decrease induced by IDN. The interactions between the two drugs suggest that their effects on cerebral hemodynamics (and pain) may be of relevance both in understanding the role of NO in migraine pathogenesis and in evaluating symptomatic treatments for migraine attacks.  相似文献   
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Basic mechanisms underlying the tolerance and reaction of the central nervous system to ionizing radiation are not known precisely. We investigated the possibility of a change in blood-brain barrier (BBB) function as a causative factor for early delayed whole-brain radiation-induced cerebral dysfunction. Rats were exposed to conventional fractionation (200 cGy/d, 5 d/wk; total dose, 4000 cGy). BBB changes were assessed by means of the quantitative 14C-alpha-aminoisobutyric acid technique and electron microscopy. Studies of the passage of horseradish peroxidase across the BBB permitted comparative quantitative isotopical and qualitative morphological data. Experiments were carried out 2 to 3 weeks after the completion of the radiation exposure. The transport of 14C-alpha-aminoisobutyric acid across the BBB increased significantly in cerebral cortex and cerebellar gray matter, averaging 1.3 to 1.5 times over the normal values. Electron microscopy disclosed an intense vesicular response of the cortical microvascular endothelium that occurred without the opening of the tight junctions and resulted in an intense transport of HRP across the intact endothelium. The present data indicate that moderate doses of whole-brain radiation induce well-defined changes in BBB function, which possibly are involved in the pathogenesis of radiation-induced cerebral dysfunction in humans.  相似文献   
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The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia.  相似文献   
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The clinical efficacy and the safety of ciprofloxacin was studied in 92 patients (aged 26 to 83 years; mean 57.5 years) affected by urinary tract infections (UTI) and respiratory tract infections (RTI) suffering also with various liver diseases. Ciprofloxacin was given orally at different dose regimens: 500 mg b.i.d. (22 cases), 250 mg b.i.d. (20 cases), 500 mg s.i.d. (20 cases) for the treatment of UTIs; 500 mg b.i.d. (ten cases) and 250 mg b.i.d. (20 cases) for the treatment of RTIs. The doses were not correlated to the severity of the infections. Patients were treated for five to 15 days. All the bacteria isolated from sputum or urine before treatment were sensitive to ciprofloxacin (MIC range 0.015 mg/1 to 8 mg/1). The clinical and bacteriological responses were favourable in a high percentage of patients both for RTIs and UTIs, irrespective of the dose. Side effects were infrequent (7%) and mild (nausea, gastralgia, oral candidosis), never requiring the interruption of the treatment. No change in the blood chemistry tests was observed at any dose.Die klinische Wirksamkeit und Sicherheit von Ciprofloxacin wurde bei 92 Patienten (Alter 26 bis 83 Jahre, im Mittel 57,5 Jahre), die an verschiedenen Leberkrankheiten litten, bei interkurrent aufgetretenen Harnwegs- und Atemwegsinfektionen geprüft. Ciprofloxacin wurde in verschiedenen Dosierungen oral verabreicht. Zur Behandlung von Harnwegsinfektionen wurden Dosierungen von 500 mg zweimal täglich (22 Fälle), 250 mg zweimal täglich (20 Fälle) oder 500 mg in einer täglichen Einzeldosis (20 Fälle) verabreicht. Atemwegsinfektionen wurden mit zweimal täglich 500 mg (10 Fälle) oder mit zweimal täglich 250 mg (20 Fälle) behandelt. Die Dosen wurden nicht nach dem Schweregrad der Erkrankung gewählt. Die Behandlungsdauer betrug fünf bis 15 Tage. Alle aus Sputum oder Urin vor der Therapie isolierten Bakterien waren für Ciprofloxacin empfindlich (MHK-Werte 0,015 mg/l bis 8 mg/l). Bei einem hohen Prozentsatz der Patienten mit Atemwegs- und Harnwegsinfektionen wurden unabhängig von der Dosierung günstige klinische und bakteriologische Ergebnisse erzielt. Nebenwirkungen traten selten auf (7%) und waren leicht (Übelkeit, Magenschmerzen, orale Candidiasis). Ein Therapieabbruch war in keinem Fall nötig. Bei keiner der angewandten Dosierungen waren Änderungen in den klinisch-chemischen Parametern festzustellen.  相似文献   
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