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Brain tumors are the most common solid tumor in childhood. Surgery and/or fractionated radiotherapy are conventional treatment modalities. Stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (FSRT) are advanced radiation therapy techniques that have been frequently used in adults with brain tumors but they are less frequently used in pediatric patients. SRS and FSRT can potentially add to the armamentarium against brain tumors in children. This article will review the role of SRS and FSRT in the management of pediatric brain tumors.  相似文献   
23.
Brain metastasis occurs rarely in patients with testicular cancer in the modern era where cisplatin-based chemotherapy regimens are used. The occurrence of brain metastasis can be synchronous or metachronous (with or without concurrent systemic disease). Long-term survival can be achieved in some patients. The vast majority of testicular cancer cases with brain metastasis reported in the literature involve nonseminomatous germ cell tumor and this subtype will be the focus of this review. This article reviews the literature of the diagnosis and management of brain metastasis from nonseminomatous germ cell tumor of the testis.  相似文献   
24.
Background: Laparoscopy is increasingly used in conditions complicated by peritonitis, e.g., peptic ulcer perforation. Of some theoretical concern is the capnoperitoneum, which may aggravate peritonitis and induce septic shock due to increased intraabdominal pressure and distension of the peritoneum. This animal study was devised to analyze the effectiveness of laparoscopic versus traditional open repair of gastric perforation and abdominal lavage for associated peritonitis. Methods: To simulate gastric perforation, female Duroc pigs were subjects to standardized gastrotomy. Either 6 or 12 h after gastric perforation, the animals underwent either traditional open or laparoscopic repair of the gastric defect and peritoneal lavage. The subjects were divided into the following four groups: peritonitis for 6 h and open surgery (group I) or laparoscopic surgery (group II); peritonitis for 12 h and open surgery (group III) or laparoscopic surgery (group IV). After an observation period of 6 days, the surviving animals were killed. The main outcome criteria were survival, perioperative changes of hemodynamics suggestive for septic shock, bacteremia, and endotoxemia. Results: There were no significant differences between group I and II. Mortality was 22% in group III, as compared to 78% in group IV (p= 0.045). In group IV, the incidence of perioperative bacteremia and plasma endotoxin concentrations were significantly higher than in group III. Concomitantly, decreased mean arterial pressure and systemic vascular resistance, and increased cardiac output suggested a higher incidence of septic shock in group IV. Conclusion: Critical appraisal of laparoscopic surgery is warranted in conditions associated with severe, longstanding peritonitis. Received: 28 February 1997/Accepted: 1 July 1997  相似文献   
25.
PURPOSE: To assess the analgesic efficacy and functional outcome of postoperative epidural infusion of ropivacaine combined with sufentanil in a randomized, controlled trial. METHODS: Thirty-two ASA I-III patients undergoing elective total hip replacement (THR) were included. Lumbar epidural block using 0.75% ropivacaine was combined with either propofol sedation or general anesthesia for surgery. On arrival in the recovery room, the epidural infusion was commenced at a rate in mL calculated as follows: (height in cm - 100) x 0.1. Eleven patients received an epidural infusion of ropivacaine 0.1% with 0.5 microg x mL(-1) sufentanil (Group R+S0.5), ten patients ropivacaine 0.1% with 0.75 microg x mL(-1) sufentanil (Group R+S0.75), and 11 patients ropivacaine 0.1% with 1 microg x mL(-1) sufentanil (Group R+S1) over a postoperative study period of 44 hr. All patients had access to iv piritramide via a patient-controlled analgesia (PCA) device. Postel-Merle-d'Aubigné scoring system (PMA score) was assessed preoperatively, three weeks after surgery, and three months after surgery by an orthopedic surgeon blinded to study group. RESULTS: Motor block was negligible in all three groups. After eight hours of epidural infusion, sensory block had regressed completely in all patients. There was no significant difference with regard to visual analogue scale (VAS) scores (at rest: P = 0.55, on movement: P = 0.63), consumption of rescue medication (P = 0.99), patient satisfaction (P = 0.22), and the incidence of adverse events. All treatment regimens provided effective postoperative analgesia with only a minimal use of supplemental opioid PCA. There was no difference between groups regarding orthopedic PMA score (pain: P = 0.24, mobility: P = 0.65, and ability to walk: P = 0.44). CONCLUSION: Ropivacaine 0.1% with 0.5 microg x mL(-1) sufentanil for postoperative analgesia after THR provides efficient pain relief and, compared with 0.75 and 1 microg x mL(-1) sufentanil, reduces sufentanil consumption without compromise in patient satisfaction, VAS scores, and functional outcome.  相似文献   
26.
Hepatocyte transplantation   总被引:2,自引:0,他引:2  
The purpose of this report is to summarize data collected over the past several years in the field of hepatocyte transplantation. Herein, a novel method of intraperitoneal transplantation of hepatocytes attached to collagen-coated microcarriers (or a totally biodegradable collagen sponge) is described, resulting in correction of specific genetic liver defects in rats and improved survival in rats undergoing 90% partial hepatectomy. Transplanted cells/matrix form well-vascularized aggregates in the peritoneal cavity; transplanted hepatocytes can be identified by light microscopy using immunohistochemical methods. Prolongation of transplanted hepatocyte survival and function was demonstrated by pretreatment of cells with ultraviolet irradiation. The ability of transplanted cells to proliferate was examined using both biochemical and morphologic criteria. Finally, a method of harvesting, cryopreserving, andin vivo functional testing of human hepatocytes is described.Presented at the Proceedings of the International Meeting on Normal and Neoplastic Growth in Hepatology, Bari, Italy, June 1989.Supported by National Institutes of Health (NIDDK) grant DK38763 and a Veterans Administration Merit Review Award.  相似文献   
27.

Objective

Researchers traditionally rely on participant self-report for contraceptive use. We hypothesized that self-reported contraceptive use by clinical research participants may disagree with objectively measured hormonal status.

Study design

We enrolled women in Harare, Zimbabwe, aged 18–34, who by self-report had not used hormonal or intrauterine contraception for >30 days, or depot medroxyprogesterone acetate for >10 months, into a study designed to assess biologic changes with contraceptive initiation and use. Blood samples obtained at enrollment and each follow-up visit (N=1630 from 447 participants) were evaluated by mass spectrometry for exogenous hormones. We individually interviewed a subset of participants (n=20) with discrepant self-reported and measured serum hormones to better understand nondisclosure of contraceptive use.

Results

Discrepant with self-reported nonuse of hormonal contraception, synthetic progestogens were detectable in 120/447 (27%, 95% confidence interval 23%–31%) enrolled women. Measured exogenous hormones consistent with use of contraceptive pills (n=102), injectables (n=20) and implants (n=3) were detected at enrollment, with 7 women likely using >1 contraceptive. In-depth interviews revealed that participants understood the requirement to be hormone free at enrollment (100%). Most (85%) cited partner noncooperation with condoms/withdrawal and/or pregnancy concerns as major reasons for nondisclosed contraceptive use. All interviewed women (100%) cited access to health care as a primary motivation for study participation. Of participants who accurately reported nonuse of hormonal contraception at enrollment, 41/327 (12.5%) had objective evidence of nonstudy progestin use at follow-up that disagreed with self-reported nonuse.

Conclusions

Women joining contraceptive research studies may misrepresent their use of nonstudy contraceptive hormones at baseline and follow-up. Objective measures of hormone use are needed to ensure that study population exposures are accurately categorized.

Implications statement

Among Zimbabwean women participating in a contraceptive research study, 27% had objective evidence of use of nonstudy contraceptives at enrollment that disagreed with self-report. Studies that rely on self-report to identify contraceptive hormone exposure could suffer from significant misclassification.  相似文献   
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29.
Immunoglobulin kappa gene usage and somatic mutation patterns were studied in a series of 47 IGKV-J rearrangements amplified in 42 follicular lymphoma (FL) cases. The IGKV1-39/1D-39 gene predominated and was significantly over-represented compared to normal cells, autoreactive cells or other B cell lymphomas. The impact of somatic hypermutation varied significantly; nevertheless, mutation distribution patterns indicated pressure for preservation of the B cell receptor. In conclusion, the present series demonstrates biased usage of IGKV genes in FL and alludes to the important role of immunoglobulin kappa light chains in antigen selection of the clonogenic B cells in FL.  相似文献   
30.
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