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1.
Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
2.
3.
Myo-inositol transport in the central nervous system   总被引:18,自引:0,他引:18  
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4.
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   
5.
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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6.
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   
7.
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   
8.
Labial adhesions are usually seen in early childhood or in the postmenopausal years, but this clinical entity is rarely seen in the reproductive years. We report a case of labial adhesion with acute urinary retention secondary to Bartholin's abscess in a reproductive‐aged woman with normal menstrual periods. We emphasize the possible occurrence of labial adhesion following Bartholin's abscess in the reproductive years with normal estrogen levels.  相似文献   
9.
Heparin-induced thrombocytopenia is characterized by moderate thrombocytopenia and thrombotic complications, whereas quinine/quinidine-induced thrombocytopenia usually presents with severe thrombocytopenia and bleeding. Using flow cytometry and assays of procoagulant activity, we investigated whether sera from patients with these immune drug reactions could stimulate normal platelets to generate platelet-derived microparticles with procoagulant activity. Sera or purified IgG from patients with heparin-induced thrombocytopenia stimulated the formation of platelet-derived microparticles in a heparin-dependent fashion. Further studies showed that heparin-induced thrombocytopenia sera also produced a marked increase in procoagulant activity. In contrast, sera from patients with quinine- or quinidine-induced thrombocytopenia did not generate platelet-derived microparticles nor generate increased procoagulant activity. However, quinine/quinidine-induced thrombocytopenia sera produced a significant increase in the binding of IgG to platelets in a drug-dependent fashion, whereas sera from patients with heparin-induced thrombocytopenia demonstrated no drug-dependent binding of IgG to platelets. We also observed increased levels of circulating microparticles in patients with acute heparin-induced thrombocytopenia compared with control patients. Our observations indicate that the generation of procoagulant platelet-derived microparticles in vivo is a plausible explanation for the thrombotic complications observed in some patients with heparin-induced thrombocytopenia.  相似文献   
10.
Bone metastases frequently occur in the advanced stages of breast cancer. At this stage, the disease is deemed incurable. To date, the mechanisms of breast cancer‐related metastasis to bone are poorly understood. This may be attributed to the lack of appropriate animal models to investigate the complex cancer cell–bone interactions. In this study, two established tissue‐engineered bone constructs (TEBCs) were applied to a breast cancer‐related metastasis model. A cylindrical medical‐grade polycaprolactone‐tricalcium phosphate scaffold produced by fused deposition modelling (scaffold 1) was compared with a tubular calcium phosphate‐coated polycaprolactone scaffold fabricated by solution electrospinning (scaffold 2) for their potential to generate ectopic humanised bone in NOD/SCID mice. While scaffold 1 was found not suitable to generate a sufficient amount of ectopic bone tissue due to poor ectopic integration, scaffold 2 showed excellent integration into the host tissue, leading to bone formation. To mimic breast cancer cell colonisation to the bone, MDA‐MB‐231, SUM1315, and MDA‐MB‐231BO breast cancer cells were cultured in polyethylene glycol‐based hydrogels and implanted adjacent to the TEBCs. Histological analysis indicated that the breast cancer cells induced an osteoclastic reaction in the TEBCs, demonstrating analogies to breast cancer‐related bone metastasis seen in patients.  相似文献   
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