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1.
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed.  相似文献   
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OBJECTIVE: To assess the efficacy of a longer acting preparation of the gonadotrophin releasing hormone (GnRH) analogue goserelin (Zoladex LA, 10.8 mg) in 12 girls with central precocious or early puberty. METHODS: Two girls started treatment de novo; the remainder had been on suppressive treatment for a median duration of 1.5 (range, 0.2-5.6) years. Assessment comprising auxology, pubertal staging, and pelvic ultrasound examination was carried out at weeks 0, 4, 8, 10, and 12 (first cycle) and weeks 8, 10, and 12 (second cycle) to evaluate the required injection frequency. Thereafter, assessment was performed on the day of injection. Zoladex LA was given every 12 weeks unless pubertal progression occurred. RESULTS: Satisfactory control was achieved in eight patients using this regimen, and three patients required more frequent injections. One girl was removed from the study because of clinical progression and extreme mood swings. No serious adverse effects occurred. Mean height velocity during the study period was 4.5 cm/year (range, 3.1-6.6) compared with 6.5 cm/year (range, 3.8-9.6) before treatment in nine patients for whom data were available. CONCLUSIONS: Zoladex LA was effective in controlling precocious puberty in girls when given at intervals of 9-12 weeks and it is recommended that an initial assessment is made eight weeks after beginning treatment.  相似文献   
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Inactivation of the p53 tumor suppressor gene has been implicated in the pathogenesis of numerous human cancers, including osteosarcomas. Appendicular osteosarcomas of the dog appear to be a good model for their human equivalent with regard to biologic behavior, epidemiology and histopathology. We individually screened exons 5-8 of the p53 gene for mutations in 15 canine appendicular osteosarcomas using 'Cold' SSCP to compare the role of this gene in human and canine osteosarcoma tumorigenesis. Seven of the tumors (47%) exhibited point mutations, with one tumor possessing two mutations within different exons. Of these, seven were missense mutations and the eighth was a 'silent' mutation potentially affecting the exon 6-7 splicing region. Five of the missense mutations were located in highly conserved regions IV and V, while another corresponded with the highly conserved codon 220 mutational hotspot located outside the conserved domains. The locations and types of mutations were nearly identical to those reported in human cancer. These findings provide strong evidence of the involvement of p53 mutations in the development of canine appendicular osteosarcomas. Canine osteosarcomas appear to be a promising model for their human equivalent on a clinical, pathologic, and molecular level.   相似文献   
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One hundred patients of Diabetes Mellitus (70 with and 30 without clinical somatic neuropathy) were studied to correlate clinical severity with the magnitude of nerve conduction abnormalities. Age range was 10-79 years (mean 49) with equal number of males and females. Incidence of neuropathy was more in patients over 40 years of age (60 out of 70 patients) with duration of disease over two years (78.33%). The grades of severity were mild in 22 (31.33%), moderate in 25 (35.71%) and severe in 23 (32.86%) patients. Nerve conduction studies were carried out in 48 (27 with and 21 without clinical neuropathy) patients, using the apparatus Dantec (Cantata TM). The nerves (median, peroneal and sural) were stimulated at two points and the recording of latency; amplitude (micro V) and motor and sensory nerve conduction velocities (m/s) were done under identical environmental conditions. Sensory nerve conduction velocity was more affected than motor velocity. In the 21 patients without clinical neuropathy, 14 showed abnormalities indicating early involvement of peripheral nerves. Reduction of motor nerve conduction velocity was more in patients with moderate and severe grades. The reduction was more in lower than in upper limbs. Nerve conduction abnormality helps in diagnosis in diabetic neuropathy even in preclinical state and correlates with severity, in clinical neuropathy.KEY WORDS: Diabetic neuropathy, Nerve conduction abnormality, Peripheral neuropathy  相似文献   
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The Melanotic Neuroectodermal Tumor of Infancy (MNTI) is an asymptomatic, pigmented neoplasm characterized by a fast and locally aggressive growth along with a rare tissue formation. In the diagnostic process, the use of imaging exams can suggest a local destruction suggestive of malignancy, a sign of bone remodeling and expansion. Therefore, as any early diagnosis minimizes risks and improves the prognosis of treatment for the patient, the aim of this study was, based on a clinical case report, to corroborate the use of histopathological analysis associated with immunohistochemistry. Thus, we conclude that the immunohistochemical exam is of great importance for a better complementation of the MNTI diagnosis process. In addition, it can reveal signs of possible aggressive growth.  相似文献   
10.

Ethnopharmacological relevance

Petiveria alliacea L. (tipi) a shrub from Phytolaccaceae family is popularly used in folk medicine for treating a wide variety of disorders in South and Central America.

Aim of the study

To investigate the neuropharmacological properties on experimental animals.

Materials and methods

The acetate (FA), hexanic (FH), hydroalcoholic (FHA) and precipitated hydroalcoholic (FHAppt) fractions from the root of tipi were studied to investigate its pharmacological properties in the classical behavioral models (open-field, elevated plus maze-EPM, rotarod, barbiturate-induced sleeping time, forced swimming and pentylenetetrazole (PTZ)-induced convulsions tests) using mice. These fractions were administered intraperitoneally and orally to female mice at single doses of 100 and 200 mg/kg.

Results

All these fractions decreased the locomotor activity, rearing and grooming in the open-field test, suggesting a possible central depressant action. No significant effect was evident on motor coordination of the animals in the rotarod test. On EPM, all the fractions of tipi presented a significant reduction on the time of permanence in the open arms, indicating an absence of anxiolytic-like effect. In addition, the fractions increased the immobility time in the forced swimming test and potentiated pentobarbital-induced sleeping time in mice, confirmed a probable sedative and central depressant effect. Furthermore, the fractions increased the latency to the first convulsion and the lethal time of the PTZ-induced convulsions test in the animals, confirmed its popular use as anticonvulsant.

Conclusion

Our results suggest that the fractions of P. alliacea L. contains biologically active substance(s) that might be acting in the CNS and have significant depressant and anticonvulsant potentials, supporting folk medicine use of this plant.  相似文献   
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