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41.
During a 5-year period 32 children and adolescents 4 to 18 years old underwent 35 extracorporeal shock wave lithotripsy (ESWL* ) treatments for 37 calculi. The unmodified Dornier HM3 lithotriptor was used in 21 cases (60 percent) while the remaining cases were treated with the Siemen Lithostar lithotriptor. The HM3 necessitated general anesthesia in 67 percent of patients and the Lithostar necessitated intravenous sedation in 86 percent. The majority of pediatric lithotripsy treatments were performed on an outpatient basis (24) or during an overnight hospital stay (3) while 8 were done on an inpatient basis. Of the 37 stones treated with 1 ESWL session 68 percent resolved, 19 percent had residual fragments less than 4 mm., 8 percent had residual fragments greater than 4 mm. and 5 percent required an endoscopic procedure for resolution. When success rates by lithotriptor were examined no significant difference between the 2 machines was identified although the HM3 treated larger stones (p = 0.0499). There were no statistical differences in regard to success and the use of stents, patient age or stone location between the 2 lithotriptors. Three patients required adjuvant procedures, and complications and morbidity developed in 2 and 5, respectively. All children or parents were contacted for followup (range 7 to 67 months). One child required ESWL for a new stone while another passed a stone without intervention. Only 1 child with a residual fragment less than 4 mm. became symptomatic but needed no intervention while 1 of 3 with fragments greater than 4 mm. needed intervention. No patients required open or percutaneous intervention.  相似文献   
42.
The pathogenesis of hypertension in autosomal-dominant polycystic kidney disease (ADPKD) is unclear, but increased activity of the renin-angiotension system may contribute. The renal and systemic hemodynamic response to lisinopril, an angiotension converting enzyme (ACE) inhibitor, in patients with ADPKD without renal failure was compared with the response in matched unaffected family members. Mean blood pressure and renal vascular resistance decreased in the affected group after lisinopril, with no significant change in the unaffected group. Glomerular filtration rate (GFR) was unchanged and therefore filtration fraction fell significantly. Changes in urinary excretion of 6-keto-PGF1 alpha and kallikrein suggested that increased renal synthesis of PGI2 or activation of the renal kallikrein-kinin system were not likely to be responsible for the hemodynamic effects. The acute decrease in renal vascular resistance without change in GFR suggests that ACE inhibition may have a particular value in the treatment of hypertension associated with ADPKD which should be assessed by further long-term studies.  相似文献   
43.
Prior studies in our laboratory have shown that human thyroid neoplasms have a greater adenylate cyclase activity in response to thyroid stimulating hormone (TSH) than does the adjacent histologically normal thyroid tissue. However, there is little information relating activity of the TSH receptor-adenylate cyclase system to the type of thyroid neoplasm. Thyroid tissue from 67 patients was divided by clinical and histological criteria into 6 categories: normal (59), benign tumors (20), stage 1 carcinoma—intrathyroidal involvement only (25), stage 2 carcinomaregional lymph node involvement (6), stage 3 and 4 carcinoma—tissue invasion or distant metastasis (11), and medullary carcinoma (3). Adenylate cyclase activity in an 8,000 x g thyroid membrane preparation was determined in the basal state and when maximally stimulated with 300 mU/ml TSH. The cyclase responsiveness was the ratio of TSH stimulated adenylate cyclase activity compared to basal adenylate cyclase activity. The cyclase responsiveness by category is: normal, 2.8±0.2 (mean ± SEM); benign, 17.9±2.4; stage 1 carcinoma, 9.2±1.9; stage 2 carcinoma, 4.0±1.0; stage 3 and 4 carcinoma, 1.6±0.4; and medullary carcinoma, 1.05±0.04 (for the neoplasms,p <0.02 by ANOVA). Tumor stage was the only correlate with this trend as other prognostic risk factors (age, sex, a history of neck irradiation, or papillary versus follicular histology) showed no difference in cyclase responsiveness. These studies demonstrate a consistent inverse correlation between adenylate cyclase responsiveness and tumor stage or aggressiveness. Cyclase responsiveness appears to have clinical application for predicting which thyroid tumors will behave aggressively.
Resumen Estudios previos en nuestro laboratorio han demostrado que los neoplasmas tiroideos humanos poseen una mayor actividad de adenilato ciclasa en respuesta a la administración de hormona estimulante de la tiroides (TSH) que el tejido tiroideo histológicamente normal adyacente. Sin embargo, existe muy poca información sobre la relation de la actividad del sistema receptor de TSH-adenilato ciclasa y el tipo del neoplasma tiroideo. Tejido tiroideo proveniente de 67 pacientes fue dividido mediante criterios chlínicos e histológicos en 6 categorias: normal (59), tumores benignos (20), extensión intratiroidea solamente en estado 1 (25), carcinoma-extensión ganglionar regional en estado 2 (6), carcinoma-invasión tisular o metástasis distantes en estados 3 y 4 (11), y carcinoma medular (3). La actividad de la adenilato ciclasa en una preparación de membrana tiroidea de 8,000 × g fue determinada en el estado basai y en estado de maxima estimulación con 300 mU/ml TSH. El grado de respuesta de la ciclasa fue la tasa de actividad de la adenilato ciclasa estimulada por TSH comparada con la actividad basai de la adenilato ciclasa. El grado de respuesta por categorías fue: normal, 2.8±0.2; tumor benigno, 17.9±2.4; carcinoma estado 1, 9.2±1.9; carcinoma estado 2, 4.0±1.0; carcinoma estados 3 y 4, 1.6±0.4; y carcinoma medular, 1.05±0.04 (para los neoplasmas,p < 0.02 por ANOVA). El estado del tumor apareció como el único factor de correlatión con esta gradación, ya que otros factures de pronóstico (edad, sexo, historia de irradiación cervical, histología papilar versus folicular) no demostraron diferencia en cuanto al grado de respuesta de la ciclasa. Estos estudios demuestran una consistente relación inversa entre el grado de respuesta de la adenilato ciclasa y el estado o agresividad tumoral. El grado de respuesta de la ciclasa parece tener aplicación clínica para predecir qué tumores tiroideos se habrán de comportar en forma agresiva.

Résumé Les études antérieures provenant de nos laboratoires ont démontré une augmentation de l'activité enzymatique de l'adénylate-cyclase en réponse à la thyroïd stimulating hormone (TSH) dans le tissu thyroïdien humain tumoral, par rapport au tissu thyroïdien adjacent normal. Cependant il existe peu de données concernant l'activité du système récepteur TSH/adénylatecyclase par rapport au type de tumeur de la thyroïde. Les tissus thyroïdiens provenant de 67 patients différents ont été repartis en 6 groupes selon des critères cliniques et histologiques: normal (59), tumeur bénigne (20), cancer stade 1 (intrathyroïdien uniquement) (25), cancer stade 2 (envahissement ganglionnaire régional) (6), cancer stade 3 et 4 (envahissement tissulaire avoisinant ou métastases à distance (11), et cancer médullaire (3). A partir d'une préparation de membrane thyroïdienne centrifugée à 8,000 × g, l'activité de l'adénylate-cyclase a été déterminée en l'état basai et après stimulation maximale par 300 mU/ml de TSH. La réponse enzymatique a été mesurée comme étant le rapport de l'activité stimulée par la TSH/activité basale. Les résultats selon les 6 groupes étaient (moyen±ET): tissu normal, 2.8±0.2; tumeur bénigne, 17.9±2.4; cancer stade 1, 9.2±1.9; cancer stade 2, 4.0±1.0; cancers stade 3 et 4, 1.6±0.4; et cancer médullaire, 1.05±0.04 (p < 0.02 par l'analyse de variance pour les néoplasies). Le stade tumoral était la seule variable corrélée avec l'activité enzymatique. L'activité enzymatique n'était pas corrélée avec l'âge, le sexe, les antécédents d'irradiation cervicale antérieure ou l'histologie (papillaire vs. folliculaire). Ces études montrent un rapport inversement proportionnel entre l'activité d'adénylate-cyclase et le degré d'agressivité tumorale ou le stade. La réponse d l'adénylate-cyclase paraît avoir une application clinique: prévoir quelles tumeurs thyroïdiennes auront une évolution agressive.


Presented at the International Association of Endocrine Surgeons in Sydney, Australia, September, 1987.

Supported in part by the Medical Research Service of the Veterans Administration.  相似文献   
44.
采用间接ELISA检测23名肾移植受者血清巨细胞病毒(CMV)抗体,共检出18名(78%)活动性CMV感染,其中10名(44%)为原发性感染。结果证实CMV-IgE和-IgA具有较好的血清学诊断价值,优于CMV-IgM。  相似文献   
45.
Nancy Kluck, Scan J. O'Connor, Victor M. Hesselbrock, Allan Tasman and Donald Maier, Lance Bauer: Variation in Evoked Potential Measures Over the Menstrual Cycle: A Pilot Study. Prog. Neuro. Psychopharmacol. Biol. Psychiat. 1992. 16(6): 901–911.

1. 1. The P3 component of a visual event related potential (ERP) was studied for five consecutive weeks in six women with normal menstrual cycles. Serum concentrations of luteinizing hormone (LH), estradiol (E2) and progesterone were studied during the same period.

2. 2. Increases in P3 amplitude, although nonsignificant, were noted in the week preceding onset of menses.

3. 3. No significant changes in reaction times to target/nontarget stimuli were noted over the same time period.

Author Keywords: Event-related potentials; females; menstrual cycle  相似文献   

46.
The performance of therapeutic aspiration in the treatment of amebic liver abscess, advocated and practiced in many centers, is controversial. Previously, this practice has been evaluated in retrospective analyses. To test the potential benefit of therapeutic aspiration, the authors undertook a prospective randomized trial in 57 patients admitted for suspected amebic liver abscess during a 15-month period. Sixteen patients were excluded from the trial. The remaining 41 patients were randomly included in one of two study groups to receive amebicidal therapy alone or amebicidal therapy coupled with image-guided percutaneous therapeutic aspiration. All patients in the trial recovered. No statistically significant benefit was demonstrated in the aspiration group for the two objective parameters evaluated: length of hospitalization and duration of time to becoming afebrile. Subjective improvement in symptoms after aspiration was greater in the aspiration group at a marginally statistically significant level. These data do not support the adjunctive performance of percutaneous therapeutic aspiration in the treatment of uncomplicated amebic liver abscess. Amebicidals alone were equally efficacious in treating the group studied.  相似文献   
47.
Ossification of the posterior longitudinal ligament (OPLL) is a progressive disorder of the spine which may result in spinal cord compression and myelopathy. While prevalent among Japanese, its occurrence in non-Orientals has been infrequently reported. Nine patients with OPLL have been diagnosed and followed at the Emory Clinic Spine Center over a 5-year period. All of the patients had been misdiagnosed before presentation. Five of the nine had undergone a total of eight ineffective operations. Failure to distinguish OPLL from other more common causes of myelopathy can result in delayed or inappropriate treatment. Illustrative cases and radiographic studies are presented.  相似文献   
48.
49.
The beta-amyloid (Abeta) precursor protein (APP) is cleaved sequentially by beta-site of APP-cleaving enzyme (BACE) and gamma-secretase to release the Abeta peptides that accumulate in plaques in Alzheimer's disease (AD). GGA1, a member of the Golgi-localized gamma-ear-containing ARF-binding (GGA) protein family, interacts with BACE and influences its subcellular distribution. We now report that overexpression of GGA1 in cells increased the APP C-terminal fragment resulting from beta-cleavage but surprisingly reduced Abeta. GGA1 confined APP to the Golgi, in which fluorescence resonance energy transfer analyses suggest that the proteins come into close proximity. GGA1 blunted only APP but not notch intracellular domain release. These results suggest that GGA1 prevented APP beta-cleavage products from becoming substrates for gamma-secretase. Direct binding of GGA1 to BACE was not required for these effects, but the integrity of the GAT (GGA1 and TOM) domain of GGA1 was. GGA1 may act as a specific spatial switch influencing APP trafficking and processing, so that APP-GGA1 interactions may have pathophysiological relevance in AD.  相似文献   
50.
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