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111.
The CT findings of 19 children under 16 years of age with primary brain tumors in the cerebral hemisphere were investigated with special reference to the existence of cerebral hemiatrophy ipsilateral to the side of the tumor. "Ipsilateral cerebral hemiatrophy" was observed in four of 19 cases (21%). These included two cases with germinoma in the basal ganglia and two with low-grade astrocytoma in the frontal and occipital cortex. This peculiar CT finding was not specific to the location or histology of the tumor. The four cases were characterized by slow progression, which contrasted with the rapid progression of tumors shown in seven cases with a mass effect on CT.  相似文献   
112.
Familial occurrence of differentiated, nonmedullary thyroid carcinoma in 23 patients from 11 families is reported. Five patients were male and 18 were female. The familial relationship of patients was parent and child in 12 cases from 6 families, and siblings in 11 cases from 5 families. Carcinoma of other organs was noted in other members in 8 families. Histological examination revealed 18 papillary, 2 follicular, and 2 anaplastic carcinomas (the 2 anaplastic carcinomas were considered to be transformed from preexisting differentiated carcinoma). In 1 case, the histological type was unknown. The average diameter of the primary lesion was 29.9 mm. Cervical lymph node metastasis was found in 77.8% and local recurrence in 28.6% of the patients. Solid and invasive growth was dominant. On HLA typing, phenotypes of B7 and DR1 were significantly redominant in familial patients compared with nonfamilial patients and normal Japanese. Moreover, the haplotype of B7-Cw7-DR1 was observed in 5 of 13 patients tested. It is suggested from these observations that some types of differentiated, nonmedullary thyroid carcinoma may show familial occurrence and that they may have common factors with regard to the genetic and immunologic basis of the disease.
Resumen Se informa la ocurrencia familiar de carcinoma bien diferenciado, no medular, de tiroides en 23 pacientes provenientes de 11 familias, 5 hombres y 18 mujeres. La relación familiar fue padre e hijo en 12 casos de 6 familias, y hermanos en 11 casos de 5 familias. Se observé la presencia de carcinoma de otros órganos en otros miembros de 8 familias. El examen histopatológico reveló 18 carcinomas papilares, 2 foliculares, y 2 anaplásicos (los 2 fueron considerados como transformación de carcinomas diferenciados preexistentes). En un caso no fue conocido el tipo histológico. El diámetro promedio de la lesión primaria fue 29.9 mm. Se hallaron metástasis en ganglios cervicales en 77.8% de los pacientes y recurrencia local en 28.6%. El crecimiento sólido e invasivo apareció como característica dominante. En la tipificación HLA aparecieron como significativamente predominantes los fenotipos de B7 y DR1 en pacientes familiares en comparación con pacientes no familiares y japoneses normales. Por otra parte, el halotipo de B7-CW7-DR1 fue observado en 5 de 13 pacientes investigados.Como resultado de estas observationes se sugiere que algunos tipos de carcinomas diferenciados, no medulares, pueden demostrar ocurrencia familiar y que pueden poseer factores comunes relacionados con las bases genéticas e inmunológicas de la enfermedad.

Résumé On a étudié les caratéristiques du cancer de la thyroïde, dans sa variété différenciée non médullaire, survenu chez 23 patients provenant de 11 familles. Cinq patients étaient des hommes, 18 des femmes. La relation familiale était parent/enfant dans 12 cas provenant de 6 familles, et frère/soeur dans 11 cas provenant de 5 familles. Des membres de 8 autres familles présentaient un cancer d'un autre organe. Il y avait 18 cancers papillaires, 2 cancers folliculaires, et 2 cancers anaplasiques (on a considéré que les 2 cancers anaplasiques étaient des transformations à partir de cancers différenciés préexistants). Dans un cas, le type histologique était inconnu. Le diamètre moyen de la lésion primitive était de 29.9 mm. On a retrouvé des métastases ganglionnaires cervicales chez 77.8% des patients et une récidive locale chez 28.6%. Les tumeurs étaient principalement solides et invasives. Par rapport aux cancéreux non familiaux et à la population japonaise normale, il y avait plus de phénotypes B7 et DR1 au système HLA. L'haplotype B7-CW7-DR1 était observé chez 5 des 13 patients testés.On suggère que certains types de cancer différenciés, non médullaires, ayant des facteurs communs génétiques et immunologiques, peuvent survenir dans une même famille.


Presented at the International Association of Endocrine Surgeons in Sydney, Australia, September, 1987.  相似文献   
113.
Clinicopathologic studies were performed to establish rational criteria for total thyroidectomy as a treatment of follicular carcinoma. During the 4-year period from 1981 to 1984, total thyroidectomy was carried out on 23 patients in whom unequivocal vascular invasion and/or obvious extracapsular extension were disclosed on pathological study of the primary thyroid lesion. Although occult metastatic lesions were detected postoperatively in 5 patients, no distant metastases have been found in 12. Distant metastasis was clinically manifest on admission in the other 6 patients. The degree of vascular invasion at the primary lesion was not correlated with the occurrence of distant metastasis. However, 10 of the 15 patients with tumors characterized by a thick fibrous capsule had distant metastases, while all but 1 of 8 patients with a thin capsule showed no metastasis. Apparent capsular invasion seemed to increase the relative risk of distant metastasis. On the other hand, solid clusters of tumor cells containing a variable number of small follicles, which characterize Langhans' wuchernde Struma, were found in 6 patients, and 5 of them showed distant metastases. Thus, total thyroidectomy should be considered when (a) distant metastases are clinically apparent, (b) the primary lesion has a thick fibrous capsule with or without obvious capsular invasion, or (c) solid clusters of tumor cells are demonstrated microscopically.
Resumen Se realizaron estudios clinicopatológicos con el propósito de establecer criterios racionales para la tiroidectomía total en el tratamiento del carcinoma folicular. En el curso de un perfodo de 4 anos entre 1981 y 1984, se realizó tiroidectomía total en 23 pacientes en quienes se halló inequívoca invasión vascular y/o obvia extension extracapsular en el examen histopatológico de la lesión tiroidea primaria. Aunque postoperatoriamente se detectaron lesiones metastáticas ocultas en 5 pacientes, no se encontraron metástasis distantes en 12. Metástasis distantes eran clínicamente manifiestas en el momenta de la admisión en los otros 6 pacientes. El grado de invasión vascular en la lesión primaria no apareció correlacionado con la ocurrencia de metástasis distantes. Sin embargo, 10 de los 15 pacientes con tumores caracterizados por una cápsula gruesa y fibrosa tenían metástasis distantes, mientras solo 1 de 8 pacientes con tumores de cápsula fina mostró metástasis. La invasión capsular aparente parece incrementar el riesgo relativo de metástasis distantes. Por otra parte, agrupaciones sólidas de células tumorales con presencia de números variables de folículos pequeños, que caracterizan al wuchernde Struma de Langhans, fueron encontrados en 6 pacientes, 5 de los cuales mostraron metastasis distantes. Por lo tanto, se debe considerar la tiroidectomía total cuando: (a) haya metástasis distantes clínicamente aparentes, (b) la lesión primaria tenga una gruesa cápsula fibrosa con o sin invasión capsular obvia, y (c) se demuestren microscópicamente agrupaciones sólidas de células tumorales.

Résumé Une étude clinicopathologique a été menée pour déterminer les critères de thyroïdectomie totale comme traitement dans le cancer folliculaire de la thyroïde. Pendant 4 ans, de 1981 à 1984, 23 patients ont subi une thyroïdectomie totale pour envahissement vasculaire non équivoque et/ou extension extracapsulaire évidente découverte sur la pièce d'exérèse initiale. Cinq patients avaient des métastases occultes découvertes dans la période postopératoire, 6 avaient des métastases cliniquement évidentes, alors que 12 ne présentaient aucun signe de métastase à distance. Le degré d'envahissement vasculaire de la lésion primitive n'était pas corrélé avec la survenue de métastases à distance. Cependant, 10 des 15 patients à tumeurs caractérisées par un épaississement de la capsule fibreuse avaient des métastases à distance, alors que 7 des 8 patients avec une capsule mince n'avaient pas de métastases. L'envahissement capsulaire était associé à un plus grand risque de métastases à distance. Des amas solides de cellules tumorales contenant de petits follicules, le wuckernde struma de Langhans, étaient retrouvés dans 6 cas, dont 5 avaient des métastases à distance. Ainsi, la thyroïdectomie totale est préconisée lorsque (a) des métastases à distance sont cliniquement évidentes, (b) la lésion primitive possède une capsule fibreuse épaisse avec ou sans envahissement évident, et (c) on met en évidence des cellules tumorales en amas microscopiquement.


Presented at the International Association of Endocrine Surgeons in Sydney, Australia, September, 1987.  相似文献   
114.
Two patients with "my hand" sign in association with tactile extinction from callosal lesion, one due to left anterior cerebral artery occlusion, the other due to right anterior cerebral artery aneurysm rupture, were reported. The examination of "my hand" sign was performed with the methods proposed by Brion et al. Our patients correctly responded when they grasped their own or the examiner's thumb with their left hand. But they replied "my finger"when they grasped not only their own but also the examiner's thumb with their right hand. Left tactile extinction was observed after a routine extinction test in one patient, and it was observed in the other after the following method: both patient's index fingers were disposed in his midline position. In these methods of extinction test, they made errors in saying "right" when both fingers were touched simultaneously. However, they said "both" when their right index finger alone was touched (synchiria) during an extinction test using the following method: both index fingers of patients were approached by examiner to touch each other or for one of them to touch the examiner's finger. When they were asked whose finger they touched in this method (whose finger test), they made the same errors as seen in "my hand" sign test. These test results suggest that there is a common underlying mechanism in the "my hand" sign and extinction, because the sense of double stimulations felt when only one stimulation is given (synchiria), is a possible explanation for the "my hand" sign and the pathogenesis of synchiria appears to be related to extinction.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
115.
The effect of aging on 11C-N-methylspiperone binding to living human striatum was demonstrated using positron emission tomography. The 11 normal volunteers (22 to 72 years old) participated in this study. The uptake of 11C-N-methylspiperone in the brain following intravenous injection was highest in the striatum in individual subject. And the uptake in the striatum only gradually increased until the end of the study. The uptake of 11C-N-methylspiperone in cerebellum peaked within 10 minutes following injection and then rapidly dropped. The association rate constant "k3" was calculated from the slope of the radioactivity-ratio of striatum to cerebellum versus the equivalent time. The equivalent time was calculated from the radioactivity of cerebellum as an input function. The exponential decrease of the k3 value with aging was observed. The k3 value of the youngest subject (22 years old, male) was 0.035/min, while that of the oldest one (72 years old, male) was found to be 0.020/min. These data suggested that the dopaminergic activity through D2 dopamine receptors reduces with aging in human striatum.  相似文献   
116.
Transient induction of single GST-P positive hepatocytes by DEN   总被引:12,自引:3,他引:9  
The single cells positive for placental glutathione S-transferase(GST-P), detectable in livers of rats soon after treatment withhepatocarcinogens, are possible ‘initiated cells’,the hypothesis tested in the present series of experiments.No low dose threshold was observed in male Sprague-Dawley ratsat different single doses of diethylnitrosamine (DEM) althougha plateau was reached between 160 and 200 mg/kg body weight.At the latter single dose 12 400 positive cells/cm3 were observedimmunohistochemically in rat livers after one week, the numbersthen decreasing to week 8 and thereafter rising again. In thenumbers then decreasing to week 8 and thereafter rising again.In the early stages single cells predominated but with timea gradual increase in mini-foci and larger lesions became evident.Application of selection pressure (feeding of diet containing0.02% 2-AAF plus partial hepatectomy) to rats 2–24 weeksafter single DEN-treatment resulted in the formation of largefoci positive for GST-P, especially in the early stages, thegrowth response being less pronounced with time. The numberof foci, on the other hand. was correlated with the number offoci, on the other hand, was correlated with the number ofsingle cells/mini-foci detected inhepatectomy tissue of thesame individuals. These results suggest that the early GST-Ppositive populations could be the precursor for preneoplasticfoci and nodules.  相似文献   
117.
Summary Effects of verapamil on the acetylcholine (ACh)-induced K+ current were examined in single atrial cells, using the tight-seal whole-cell clamp technique. The pipette solution contained guanosine-5-triphosphate (GTP) or guanosine-5-O-(3-thiotriphosphate) (GTP-S, a non-hydrolysable GTP analogue). In GTP-loaded cells, ACh induced a specific K+ current, which is known to be mediated by pertussis toxin-sensitive GTP-binding (G) proteins. Verapamil (0.1–100 M) depressed the ACh-induced K+ current in a concentration-dependent fashion. In GTP-S-loaded cells, the K+ current remained persistently after wash-out of ACh, probably due to irreversible activation of G proteins by GTP-S. Verapamil (0.1–100 M) also depressed the intracellular GTP-S-induced K+ current. However, the magnitude of verapamil-depression of the K+ current in GTP-S-loaded cells was significantly smaller than that in GTP-loaded cells at concentrations between 1 and 10 M of the drug. From these results, it is suggested that verapamil may block not only the function of muscarinic ACh receptors but also of G proteins and/or the K+ channel itself and thereby depress the ACh-induced K+ current in isolated atrial myocytes.Supported by grants from the Ministry of Education, Science and Culture of Japan and the Research Program on Ca Signal Control Send offprint requests to Y. Kurachi at the above address  相似文献   
118.
AIMS: p27 is a prominent regulator of cell proliferation by universally inhibiting the cell cycle, while Jun activation domain-binding protein 1 (Jab1), a multifunctional cell signaling protein, contributes to carcinoma progression by degrading p27. In this study, we investigated the expression of these proteins in medullary thyroid carcinoma. METHODS: We immunohistochemically examined Jab1 and p27 expression in 64 medullary thyroid carcinomas. RESULTS: Of the 64 cases examined, decreased p27 expression was observed in 38 cases (59.4%). The p27 expression level was inversely linked to tumour size as well as plasma calcitonin level. Jab1 expression level was generally high, and 46 cases (71.9%) were classified as overexpressing Jab1. The incidence was higher than those in papillary and follicular carcinomas, which were previously reported. Jab1 expression level was inversely linked to that of p27, and all five cases with only cytoplasmic but not nuclear staining of p27 overexpressed Jab1. CONCLUSIONS: These findings suggest that (1) decrease in p27 expression may contribute to local tumour growth; (2) Jab1 expression is related to the progression of medullary carcinoma by decreasing the amount of p27 in the cell and accelerating its degradation; and (3) Jab1 may play a more vital role in the pathogenesis of medullary carcinoma than papillary and follicular carcinomas.  相似文献   
119.
120.
S-adenosylhomocysteine hydrolase is a prospective target for developing new anti-malarial drugs. Inhibition of the hydrolase results in an anti-cellular effect due to the suppression of adenosylmethionine-dependent transmethylations. Based on the crystal structure of Plasmodium falciparum S-adenosylhomocysteine hydrolase which we have determined recently, we performed mutational analyses on P. falciparum and human enzymes. Cys59 and Ala84 of the parasite enzyme, and the equivalent residues on the human enzyme, Thr60 and Gln85, were examined. Mutations of Cys59 and Thr60 caused dramatic impact on inhibition by 2-fluoronoraristeromycin without significant effect both on its kinetic parameters and on inhibition constant against noraristeromycin. In addition, the impact was independent from the electronegativity of the side chain of the substituting residue. These results showed that steric hindrance between a functional group at the 2-position of an adenine nucleoside inhibitor and Thr60 of the human enzyme, not an electrostatic effect, contributed to inhibitor selectivity.  相似文献   
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