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51.
Background
Glioblastoma multiforme is the most malignant form of brain tumor. Despite treatment including surgical resection, adjuvant chemotherapy, and radiation, these tumors typically recur. The recurrent tumor is often resistant to further therapy with the same agent, suggesting that the surviving cells that repopulate the tumor mass have an intrinsic genetic advantage. We previously demonstrated that cells selected for resistance to 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) are near-diploid, with over-representation of part or all of chromosomes 7 and 22. While cells from untreated gliomas often have over-representation of chromosome 7, chromosome 22 is typically under-represented. 相似文献52.
53.
Noah A Goldman Ellen B Katz Alan S Glenn Richard H Weldon Joan G Jones Uticia Lynch Melissa J Fezzari Carolyn D Runowicz Gary L Goldberg Maureen J Charron 《Modern pathology》2006,19(11):1429-1436
Glucose is provided to cells by a family of glucose transport facilitators known as GLUTs. These transporters are expressed in a tissue specific manner and are overexpressed in many primary tumors of these tissues. Regulation of glucose transport facilitator expression has been demonstrated in endometrial tissue and endometrial adenocarcinoma. The following experiments were conducted to quantify and localize the expression of GLUT1 and GLUT8 in benign endometrium and compare this expression to endometrial cancer. Endometrial tissue samples were obtained from random hysterectomy specimens of patients with benign indications for surgery and endometrial cancer. Immunoblot and immunolocatization studies were performed using GLUT1 and GLUT8 specific antisera. Endometrial samples from 65 women who had undergone hysterectomy were examined (n=38 benign, n=27 malignant). A 44 and a 35.4 kDa immunoreacive species was demonstrated in endometrium and endometrial cancer for GLUT1 and GLUT8, respectively. Upregulation of GLUT1 expression was demonstrated with increasing grade of tumors (P<0.002). GLUT8 expression was increased in all tumor subtypes compared to atrophic endometrium (P<0.001). Apical localization by GLUT1 and GLUT8 was demonstrated in endometrial glands. GLUT1 and GLUT8 demonstrated diffuse intracellular localization in the cancer subtypes. GLUT1 and GLUT8 are expressed in both human endometrium and endometrial cancer. There appears to be a step-wise progression in GLUT1 and GLUT8 expression as tumor histopathology worsens. GLUT1 and GLUT8 may be important markers in tumor differentiation, as well as providing energy to rapidly dividing tumor cells. 相似文献
54.
Objective. Neurally augmented sexual function (NASF) is the production of pleasurable genital stimulation and subsequent orgasm through the application of electrical energy to provide stimulation of the spinal cord or peripheral nerves. The purpose of this paper is to demonstrate the reproducibility of this phenomenon. Materials and Methods. Eleven otherwise healthy women, ages 32–60 years, were selected for this study. Through standard techniques, quadripolar (octopolar in the final patient) leads were placed in the epidural space percutaneuously. The lead was maneuvered initially to an L1–L2 position and then repositioned based on feedback from the patient. The patients were allowed to utilize the device ad libitum for up to 9 days. Results. Successful stimulation was achieved in 91% (10/11) of patients. These women described a greater frequency in sexual activity, increased lubrication, and overall satisfaction. A smaller subset had substantial improvement in sexual function as measured by orgasmic capacity. This subset consisted of women with secondary anorgasmia. A return of orgasmic capacity was found in 80% (4/5) of patients having secondary anorgasmia with an average intensity of ≥ 3/5 while using the device. Once the device was removed, the patients returned to their previous anorgasmic status. Conclusions. Pleasurable genital stimulation of the spinal cord is a consistently reproducible phenomenon. In a subset of the population studied, improvement in orgasmic function was noted. This was noted in the group with secondary orgasmic dysfunction. 相似文献
55.
E. Croce M. Golia M. Azzola R. Russo L. Crozzoli S. Olmi C. Pompa M. Borzio 《Surgical endoscopy》1996,10(11):1064-1068
Background: Thirty-three patients were candidates for laparoscopic choledochotomy. The indications for this operation are described.
Methods: The procedure was completed 32 times (97%). We had 29 successful common bile duct (CBD) clearances, three negative explorations,
and one failed clearance which needed to be converted to laparotomy. All the completed procedures ended with primary closure
of the main duct. Median duration of surgery was 180 min (range 100–300), including three associated laparoscopic procedures.
Results: There were three postoperative complications (9.4%), none major. Average postoperative hospital stay was 7.1 days (range
4–14). In May–June 1995 we controlled 31 out of the 32 consecutive patients (one patient was lost to follow-up) who had a
successful laparoscopic choledochotomy from October 1991 to December 1994. Median follow-up was 22 months (range 5–44). Besides
clinical control, 23 patients also had ultrasound (US) controls and 24 had blood tests. Eleven had intravenous cholangiotomography.
Two patients died 11 and 22 months after the operation for unrelated causes and without biliary symptoms. Two patients had
umbilical hernias. One had a small residual asymptomatic stone, which was removed endoscopically. None had signs of postoperative
CBD stricture. At US, CBD was ≤7 mm in 15 patients, 8–10 mm in four patients, and 10–12 mm in three patients. The last group
had preoperative CBD dilation, too. We could compare preoperative and postoperative CBD diameters in 22 patients: 11 had no
change; in nine it decreased; and two had a slight increase (8–10 mm).
Conclusions: We conclude that laparoscopic choledochotomy with primary closure is a very good operation: It has a high success rate and
low morbidity. Mortality is nil so far. Medium-term results are very positive: We had no CBD stricture and only one case of
asymptomatic residual stone, which could have been avoided. Our results suggest that intraductal biliary drainage is useless,
and its specific complications are well known.
Received: 20 October 1995/Accepted: 28 February 1996 相似文献
56.
Joan Prudic Mark Olfson Steven C Marcus Rice B Fuller Harold A Sackeim 《Neuropsychopharmacology》2004,55(3):301-312
BACKGROUND: Clinical trials indicate that electroconvulsive therapy (ECT) is the most effective treatment for major depression, but its effectiveness in community settings has not been examined. METHODS: In a prospective, naturalistic study involving 347 patients at seven hospitals, clinical outcomes immediately after ECT and over a 24-week follow-up period were examined in relation to patient characteristics and treatment variables. RESULTS: The sites differed markedly in patient features and ECT administration but did not differ in clinical outcomes. In contrast to the 70%-90% remission rates expected with ECT, remission rates, depending on criteria, were 30.3%-46.7%. Longer episode duration, comorbid personality disorder, and schizoaffective disorder were associated with poorer outcome. Among remitters, the relapse rate during follow-up was 64.3%. Relapse was more frequent in patients with psychotic depression or comorbid Axis I or Axis II disorders. Only 23.4% of ECT nonremitters had sustained remission during follow-up. CONCLUSIONS: The remission rate with ECT in community settings is substantially less than that in clinical trials. Providers frequently end the ECT course with the view that patients have benefited fully, yet formal assessment shows significant residual symptoms. Patients who do not remit with ECT have a poor prognosis; this underscores the need to achieve maximal improvement with this modality. 相似文献
57.
The purpose of the study described in this article was to compare the effectiveness of two bowel training programs for patients who had experienced a cerebrovascular accident (CVA) and to determine the length of time required to establish a regulated program. A quasi-experimental design was used to compare the existing bowel program that incorporated every-other-day digital stimulation (DS) with a program using daily DS. The convenience sample of 48 CVA patients included 23 in the control group who had DS every other day and 25 in the experimental group who had daily DS. Demographic data showed no significant differences between the two groups. The t-test showed that more subjects in the experimental group established regularity; however, the subjects in the control group who did achieve regularity took less time to do it. Subjects with right-side hemiplegia and less mobility required more time to become established. As a result of these findings, the routine protocol for bowel training in this rehabilitation unit has been changed to include daily digital stimulation. 相似文献
58.
59.
The growth and development of vegan children 总被引:1,自引:0,他引:1
The results of prospective study on the growth and diets, estimated from 7-day weighed food intake records, of 20 life vegan children (aged 5.8–12.8 years) are presented. The growth and development of the children were normal but they tended to be lighter in weight and exceptionally lean compared with standards. Heights were around the median of the Tanner-Whitehouse standards but were lower than the medians recently proposed by the Department of Health. Energy intakes were similar to those reported in children of the same age in the general population, but dietary fibre intakes were very high which may have influenced the digestible energy. Sugar provided an average 15.6% of the dietary energy and this was supplied mainly by fruit and fruit juice. Mean fat intakes were close to the dietary reference values. Daily intakes of essential nutrients generally met the amounts recommended, with the exceptions of calcium and vitamin B12 . Many children received supplementary sources of vitamin B12 and only two children had intakes below the lower recommended nutrient intake. Intakes of saturated fatty acids were low and those of linoleic acid were high. The ratio of linoleic/α-linolenic acid was high. As docosahexaenoic acid is absent from vegan diets, it is suggested that vegans should use oils with a lower ratio of linoleic/α-linolenic acid. Future studies should also consider the influence of a vegan diet on retinal function. None of the children was immunized against whooping cough and 11 had not been immunized against polio: 16 of the children had suffered from whooping cough. Future studies need to take into account factors other than diet when assessing the health of vegans. The results of this study show that children can be successfully reared on a vegan diet providing sufficient care is taken to avoid the known pitfalls of a bulky diet and vitamin B12 deficiency. 相似文献
60.
Marie-Francoise Dresse Michele David Heather Hume Herve Blanchard Pierre Russo Nicolas Van Doesberg Georges E. Rivard 《Pediatric hematology and oncology》1991,8(4):329-334
The Kasabach-Merritt syndrome is characterized by thrombocytopenia and localized coagulopathy associated with a hemangioma. Most techniques applied to eradicate the tumor or accelerate its involution (surgery, radiation therapy, embolization) are invasive and require transfusion of large amounts of blood products. In some cases, medical treatment is the only alternative. Efficacy of steroids and antifibronolytic agents has already been described, but even this approach is associated with the administration of blood products. We report two cases of infants with Kasabach-Merritt syndrome associated with cardiac and hepatic hemangiomas. At admission, both had signs of cardiac failure. They were successfully treated with prednisone and epsilon-aminocaproic acid (EACA). Blood products were not required once the diagnosis was made. These observations have important implications for the management of patients with Kasabach-Merritt syndrome because they show that even in severe cases blood transfusions can be avoided by the use of prednisone and EACA. 相似文献