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1.
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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A new method for determining cycloserine in plasma samples is described. This method is based on the derivatization of cycloserine with p-benzoquinone, a reaction that takes place at the same time as the process of plasma deproteinization due to the presence of ethanol as solvent in the solution of the derivatization reagent. Four derivatives are obtained from this reaction. The main derivative is well correlated with the cycloserine concentration. The ratio between the volumes of the plasma sample and the reagent solution is 1:2 for a p-benzoquinone concentration of 1000 microg/mL. Elution from a C18 column was isocratic, using a mobile phase containing (v/v) 85% aqueous 0.1% formic acid solution, and 15% (v/v) of a mixture of methanol and acetonitrile (1:1), with a flow-rate of 1 mL/min, at 25 degrees C. Determinations by fluorescence detection were achieved with excitation at 381 nm and emission at 450 nm, with a detection limit of 10 ng/mL for an injection volume of 5 microL. This method was validated and applied to the determination of cycloserine in blood plasma samples of several healthy volunteers.  相似文献   
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Summary The authors analyze 81 cases of cerebral abscess in children admitted to the Clinic of Neurosurgery Bucharest, from 1936 to 1964; these cases represent 15 per cent of the total number of 542 cerebral abscesses treated in the clinic.A progressive increase was found in the incidence of cerebral abscesses during the last 10 years; an increase was also observed with the increase in age-group.Of the 81 cases 49 occurred in boys.In accordance with their origin there were: 56% contiguous cerebral abscesses (46% otogenic, 6% rhinogenic, 4% other causes); 17% were associated with the congenital cyanotic disease; 15% were post-traumatic abscesses and 12% of undetermined origin.The location was supratentorial in 56 cases, infratentorial in 23 cases and supra- and infratentorial in 2 cases. There were 17 frontal locations, 17 temporal locations, 4 parietal, 2 occipital; in 10 cases two lobes were involved, in 4 cases three lobes and in 1 case one of the cerebral hemispheres. There were 23 cerebellar abscesses and in 2 cases the abscess was supra- and infratentorial.The clinical picture was dominated by the syndrome of raised intracranial pressure (80 per cent of the cases); the evolution of almost half of the cases was afebrile.Among the clinical features of cerebral abscesses in children particular stress is laid on cerebral abscess in infants and on abscesses accompanying a congenital cyanotic cardiopathy.The difficulties of differential diagnosis with focal encephalities, cortical thrombophlebitis, otogenic hydrocephalus, cerebral tumour, etc. are discussed.The treatment of cerebral abscesses in children is considered by the authors as a neurosurgical emergency. They recommend total ablation of the abscess as the best method of treatment, because of the favourable, immediate and late results (the formation of a supple cicatrix) it offers. The surgical treatment was associated with antibiotics, antioedematous medication, corticotherapy and anticonvulsants.Of the 75 children operated on 42 recovered and 12 showed improvement. There was no lethal case in the 25 cerebral abscesses operated on during the last 5 years.
Zusammenfassung Die Autoren geben eine Analyse von 81 Fällen kindlicher Hirnabszesse, die zwischen 1936 und 1964 in der Neurochirurgischen Klinik Bukarest beobachtet wurden. In dieser Zeit wurden insgesamt 542 Hirnabszesse behandelt. Die kindlichen machen davon 15% aus. Die Häufigkeit hat in den letzten Jahren zugenommen. Die Hirnabszesse sind bei älteren Kindern häufiger. Sie kommen bei Knaben häufiger vor als bei Mädchen.56% waren fortgeleitet entstanden (46% otogen, 6% rhinogen, 4% andere Ursachen). 17% traten im Verlauf angeborener Herzmißbildungen mit Zyanose auf. 15% entstanden posttraumatisch. Bei 12% war die Ursache nicht zu klären.56 Fälle lagen supratentoriell, 24% infratentoriell und 2 sowohl supra- als auch infratentoriell. 17 waren frontal, 17 temporal, 4 parietal und 2 okzipital lokalisiert. Bei 10 Fällen waren zwei Hirnlappen, bei 4 Fällen drei und bei 2 Fällen eine ganze Hirnhemisphäre befallen. Bei 23 Fällen fand sich der Abszeß im Kleinhirn.Das klinische Bild wurde von den Zeichen intrakranieller Drucksteigerung (80%) beherrscht. Beinahe 50% der Fälle verliefen afebril.Auf die Besonderheiten des Hirnabszesses bei Säuglingen und bei angeborenen Herzmißbildungen im Rahmen des Morbus Coerulius wurde eingegangen. Die Schwierigkeiten der Diagnose und der differentialdiagnostischen Abgrenzung von Herdenzephalitiden, kortikaler Thrombophlebitis, otogenem Hydrozephalus, Hirntumoren usw. wurden besprochen. Der diagnostische Wert von EEG, Angiographie und Kontrastdarstellung des Abszesses wurde betont.Als Behandlung der Wahl gilt die Totalexstirpation, weil sie die besten Früh- und Spätergebnisse gewährleistet und die resultierende Hirnnarbe weniger derb ist. Zusätzlich wurden Antibiotika, Osmotherapeutika, Kortikoide und Antiepileptika gegeben.Von 75 operierten Kindern genasen 42. Bei 12 weiteren wurde eine Besserung erzielt. In den letzten 5 Jahren wurde bei 25 operierten Kindern kein Todesfall mehr verzeichnet.

Resumen Los autores presentan el análisis de 81 casos de absceso cerebral en niños, casos que se investigaron en la Clínica de Neurocirurgía de Bucarest entre los años 1936 y 1964 y que representan un 15% del total de los 542 abscesos cerebrales registrados en la clínica.Se comprueba un crecimiento progresivo de la frecuencia de los abscesos cerebrales en los últimos 10 años; se observa tambien que la frecuencia crece paralelamente al aumento de la edad de los niños.Predominan los abscesos cerebrales entre los varones (49 casos).Según su origen se encontraron: 56% abscesos cerebrales subyacentes (46% otógenos, 6% rinógenos, 4% debidos a otras causas); 17% abscesos asociados a la enfermedad cianógena congénita; 15% abscesos post-traumáticos y 12% abscesos de origen indeterminado.Desde el punto de vista de su localización, hubo 56 casos supratentoriales, 23 casos infratentoriales y 2 casos supra e infratentoriales. Con localización frontal hubo 17 casos, temporal 17 casos, parietal 4 casos y occipital 2 casos; en 10 casos, el absceso afectó 2 lóbulos, en 4 casos 3 lóbulos y en 2 casos un hemisferio cerebral. 23 abscesos fueron cerebelosos y 2 situados encima y debajo del tentorio.El síndrome de hipertensión intracraneana predominó en el cuadro clínico (80% de los casos); y casi la mitad de los casos evolucionaron sin fiebre.Entre las peculiaridades clínicas del absceso cerebral infantil se ponen de relieve los abscesos cerebrales entre los niños de pecho y los que se asocian a una cardiopatia cianógena congénita.Se discuten las dificultades que encuentra el diagnóstico del absceso infantil en comparación con la encefalitis en el foco, la tromboflebitis cortical, la hidrocefalia otógena, el tumor cerebral, etcétera.Los exámenes paraclínicos subrayan el valor de la electroencefalografia, de la arteriografia cerebral y de la abscesografia.El tratamiento de los abscesos infantiles impone, según los autores, la urgencia neuroquirúrgica; basados en su experiencia, ellos recomiendan como método exclusivo de tratamiento la ablación total del absceso, por dar este método los resultados más favorables tanto inmediatos como ulteriores (permitiendo la formación de una cicatriz cerebral más blanda. El tratamiento quirúrgico se asoció a una medicación antibiótica, antiedematosa, a la corticoterapia y al empleo de anticonvulsivos.De los 74 niños operados sanaron 42 y mejoraron 12. En los últimos 5 años, entre los 25 abscesos cerebrales infantiles operados, no se registró ningún caso de fallecimiento.

Résumé Les auteurs présentent l'analyse clinique de 81 cas d'abcès cérébraux chez l'enfant, opérés dans la Clinique Neurochirurgicale de Bucarest (Roumanie), depuis 1936 jusqu'à 1964. Ces cas représentent 15% du nombre total de 542 abcès cérébraux hospitalisés dans cette période.On a pu constater, surtout dans les deux dernières années, une fréquence plus grande aussi bien qu'un accroissement du nombre des cas par rapport aux groupes d'âge des enfants.Le nombre de cas chez les garçons (49) l'a emporté sur ceux de l'autre sexe. La répartition des cas d'après leur origine fut la suivante: abcès de voisinage: 56% (dont 46% otogènes, 6% rhinogènes et 4% d'origine différente); abcès associes à une maladie cyanogène congénitale: 17%; abcès posttraumatiques: 15%; abcès d'origine indéterminée: 12%.La répartition des cas d'après la localisation: 56 cas furent des abcès supratentoriels, 23 cas soustentoriels et 2 cas mixtes. Parmi les 56 cas à localisation supratentorielle 17 étaient dans le lobe frontal; 17 dans le lobe temporal, 4 dans le lobe pariétal et 2 dans le lobe occipital; dans 10 cas l'abcès s'étendait à deux lobes, dans 4 cas à trois lobes et dans 2 cas l'abcès envahissait tout un hemisphère cérébral.Un syndrome d'hypertension intracranienne dominait l'aspect clinique dans 80% des cas et environ la moitié des cas eurent une évolution afébrile.Les auteurs insistent sur les particularités cliniques des abcès cérébraux chez le nourrisson et sur ceux accompagnant une cardiopathie cyanogène congénitale.On discute les difficultés diagnostiques de l'abcès cérébral chez les enfants surtout avec l'encéphalite en foyer, avec la trombophlébite corticale, l'hydrocéphalie otogène et les tumeurs cérébrales.Parmi les investigations paracliniques, on souligne la valeur de l'electroencéphalogramme, de l'angiographie cérébrale et de l'abcessographie.Les auteurs insistent sur le caractère d'urgence neurochirurgicale et, de par leur expérience, sont d'avis que le seul traitement qui puisse assurer les meilleurs résultats aussi bien immédiats que tardifs (cicatrice cérébrale plus souple) est l'ablation totale de l'abcès.Une médication antibiotique et antioedémateuse aussi bien qu'une corticotherapie et, des anticonvulsivants ont été constamment associées au traitement chirurgical.Du nombre de 75 enfants opérés, 42 ont été complètement guéris et 12 ameliorés. Dans les derniers 5 ans, il n'y eut aucun decès parmi les 25 enfants opérés pour abcès cérébral.

Riassunto Gli AA. fanno l'analisi clinica di 81 casi di ascessi cerebrali nei bambini, osservati nella Clinica Neurochirurgica di Bucarest, dal 1936 al 1964, e scelti tra 542 casi di ascessi osservati nello stesso periodo.Si nota un accrescimento notevole della casistica negli ultimi 10 anni e con l'età del malato; il sesso maschile è stato molto più frequentemente colpito (49 casi).Dal punto di vista dell'eziologia sono stati riscontrati: 56% di ascessi per contiguità, tra cui: 46% ascessi otitici, 6% ascessi rinogeni e 4% da altre cause; 17% associati a cardiopatie cianogene congenite, 15% ascessi post-traumatici e 12% ascessi d'origine sconosciuta.La sede degli ascessi è stata molto variabile: 56 ascessi erano sopratentoriali, 23 ascessi sottotentoriali e 2 sopra- e sottotentoriali insieme. Tra gli ascessi sopratentoriali sono stati osservati: 17 casi in sede frontale, 17 in sede temporale, 4 in sede parietale e 2 in sede occipitale. In 20 altri casi risultavano lesi 2 lobi cerebrali, in quattro 3 lobi ed in un caso un emisfero intero.In quadro clinico era dominato dclla sindrome di ipertensione endocranica (80% dei casi); il 50% dei malati era apirettico.Tra le forme cliniche dell'ascesso cerebrale nei bambini, si mettono in rilievo quello del neonato e quello associato alla cardiopatia cianogena congenita.Vengono indicate inoltre brevemente le difficoltà di una diagnosi differenziale tra encefalite a focolaio, tromboflebite corticale, l'idrocefalia otitica ed i tumori cerebrali. Tra le indagini paracliniche si sottolinea l'importanza dell'elettroencefalografia, dell'angiografia cerebrale e dell'ascessografia con aria.La terapia degli ascessi cerebrali nei bambini costituiscono, secondo gli AA., una necessità neurochirurgica urgente e, come tale, il metodo chirurgico di elezione è l'asportazione totale dell'ascesso, visto che i risultati, tanto immediati quanto a distanza, sono migliori dopo l'operazione: per es. si ha una gliosi cerebrale meno retrattile e quindi una minore frequenza dell'epilessia.Alla cura chirurgica si è associato la terapia antibiotica, la medicazione dell'edema cerebrale, i cortisonici ed i farmaci anticonvulsivi.Tra i 75 casi operati si notano: 42 guarigioni e 12 miglioramenti clinici. Negli ultimi 5 anni non si deplora nessun caso mortale nei 25 ascessi cerebrali operati.
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目的 在儿童骨延长的患儿中 ,为了能够有效地控制骨延长的速率 ,达到骨延长的目的 ,采用双能量X线骨质密度测量仪 (dualenergyX Rayabsorptiometry ,DEXA)监测延长断端骨矿含量 (bonemineralcontent,BMC)的变化。方法  30例患儿中有 5 0处下肢作了骨延长术 ,平均年龄10 .9岁 (5~ 17岁 ) ,引起短肢的病因不同。术后 7~ 10d开始行骨延长 ,每次延长 0 .2 5mm ,每天 4次。牵引延长期间每周扫描一次 ,拆除外固定器后每 2周扫描一次到术后 2年。DEXA扫描的分辨率是 1mm× 1mm ,扫描速度 30mm/s。比较不同延长时期中骨矿含量的变化。分析不同病因和不同外固定器之间骨矿含量变化的差别。结果 不同固定器之间骨矿含量的差别无著性意义。根据骨延长区BMC增加速率 ,将患儿分为快速组、一般组和慢速组。快速组每日BMC增加速率为 0 .3%~ 0 .6 % ,新骨生长快速 ;一般组每日BMC增加 0 .1%~ 0 .3% ,新骨中速生长 ;慢速组每日增加 <0 .1% ,新骨生成缓慢。骨矿化速率与原发病因相关。结论 DEXA能动态监测骨延长中新生骨的骨矿含量的变化 ,根据骨矿含量变化的程度 ,能够调整骨延长的速率 ,从而达到预期骨延长的目的。  相似文献   
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BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function.  相似文献   
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Bovine nodular thelitis is a granulomatous dermatitis associated with infection with acid-fast bacteria. To identify the mycobacterium responsible for this infection, we conducted phylogenetic investigations based on partial sequencing of 6 genes. These bacteria were identified as an undescribed Mycobacterium species that was phylogenetically related to M. leprae and M. lepromatosis.  相似文献   
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The aim of this study is to investigate the level of Romanian dental students’ knowledge regarding the oral cancer risk and non-risk factors as well as oral cancer signs, symptoms, and diagnostic signs. A total of 192 first- to sixth-year undergraduate dental students (mean age 22.20?±?2.94 years) who consented to participate in the study filled in a questionnaire enquiring about their knowledge of oral cancer. A score of the oral cancer knowledge was calculated for each participant based on their correct answers. Regarding the knowledge of oral cancer risk factors, the vast majority of the students correctly recognized tobacco (96.8 %), having a prior oral cancer lesion (85.1 %), the consumption of alcohol (77.7 %), and older age (64.2 %). Respectively, 87.7 and 54.3 % knew the tongue and the floor of mouth to be the most common oral cancer sites. Of the students, 71.3 % agreed that oral cancer examinations for those 20 years of age and older should be provided during regular periodic health examinations, 92.9 % considered that patients with suspicious oral lesions should be referred to specialists, and 84.6 % agreed that oral cancer examinations should be a routine part of a comprehensive oral examination. A significant association was found between the year of study in the dental school, age, and knowledge of the oral cancer knowledge scores. Although students’ knowledge increased with academic year, there is a clear need to enhance the dental curricula in oral cancer clinical training in oral cancer prevention and examination for dental students.  相似文献   
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