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971.
Summary Ependymomas, glial neoplasms usually arising in the posterior fossa or spinal cord, rarely metastasize outside the central nervous system. We have reviewed all 81 ependymomas evaluated at MSKCC between 1956–1989. Five (6.2%) had extraneural metastases (ENM). The primary tumor was in spinal cord in 3 patients and the cerebral hemisphere in 2. Two tumors were histologically anaplastic; 3 were histologically benign. The 5 patients were 3, 3, 3.5, 16 and 37 years old. Time from initial diagnosis to development of ENM was 0, 15, 35, 40, and 288 months. At the time of ENM the primary tumor was progressing in 4/5 patients. Prior therapy had included resection plus radiation therapy (RT) (1), RT plus chemotherapy (1), resection plus RT plus chemotherapy (2). One patient had not received prior therapy because ENM were present at diagnosis. The sites of ENM included lung and thoracic lymph nodes (2), pleura and peritoneum (2), and liver (1). Both patients with peritoneal ENM had had ventriculoperitoneal shunts. ENM did not correlate with histologic grade, age, or degree of surgical resection. When patients with ependymoma develop signs or symptoms of systemic disease such as abdominal pain, cough, or adenopathy, ENM should be considered. 相似文献
972.
Christopher G. Petr Ph.D. John Pierpont MSW 《The journal of behavioral health services & research》1992,19(2):195-206
The objectives of this study were to identify the strengths and weaknesses of Minnesota’s Comprehensive Children’s Mental Health Act of 1989 and its early implementation in Hennepin County, Minn. Data were collected from official documents and key informants relative to three implementation criteria: (1) community-based and family-centered values; (2) the range, coordination, and affordability of services; and (3) process, outcome, and consumer accountability. Findings suggest that the state law is a laudable, yet seriously limited, attempt to reform the system of care for children with emotional disorders. While the law is strong in its intent regarding community-based value, range, and coordination of services as well as process accountability, implementation has been hampered by weaker intent with respect to other criteria and by a lack of a comprehensive financing plan. Despite these limitations in the state law, Hennepin County has moved to use the law as leverage to improve the local system of care. Implications for reformers in other states center on the issues of state/county relationships, scope of initial efforts, choice of organizational structure, and the interplay of financing and accountability issues. 相似文献
973.
Joseph K. Chiu Shiao Y. Woo Joann Ater John Connelly Janet M. Bruner Moshe H. Maor Jan van Eys Mary Jane Oswald Rick Shallenberger 《Journal of neuro-oncology》1992,13(3):283-290
Summary Between 1955 and 1986, 25 children (aged 2 weeks to 15 years) were treated for intracranial ependymoma at M.D. Anderson Cancer Center. Nine patients had supratentorial primaries (5 high-grade, 4 low-grade), and 16 had infratentorial primaries (9 high-grade, 7 low-grade). Five patients had gross complete resection and 20 had incomplete resection. Seven patients received craniospinal irradiation (25–36 Gy to the neuroaxis, 45–55 Gy to tumor bed), 12 received local field irradiation (29–60 Gy, median 50 Gy). Five infants had adjuvant chemotherapy without radiotherapy, and 6 children had postradiotherapy adjuvant chemotherapy, and 12 patients had salvage chemotherapy with various agents and number of courses. Eight patients are alive, disease-free and without relapse from 1 year to 12 1/2 years from diagnosis (median 42 months). The primary failure pattern was local recurrence. The data suggest that 1) the long-term cure rate of children with ependymoma is suboptimal; 2) histologic grade may be of prognostic importance for supratentorial tumors; 3) prognosis appears worse for girls and infants under 3 years of age; 4) in well-staged patients routine spinal irradiation could be omitted; 5) the role of adjuvant chemotherapy is unclear.
Address for offprints: Shiao Y. Woo, Department of Radiation Oncology, 6565 Fannin, M.S. DB1-37, Houston, Texas 77030, USA 相似文献
974.
975.
MD MS Gregory L Larkin PhD John Moskop MD FACEP Arthur Sanders MD JD FACEP Arthur Derse 《Annals of emergency medicine》1994,24(6)
Confidentiality is a promise rooted in tradition, law andmedical ethics. Emergency physicians treat a variety of patients to whom confidentiality is of vital importance: employees, celebrities, victims of violence or disaster, minors, students, criminals, drug abusers, and patients with STDs. EDs should develop methods of ensuring confidentiality for all patients.34Although confidentiality is an important principle thatshould be respected and guarded, it is not absolute. Various laws mandate disclosure of certain patient information; in addition, an overriding moral duty may occasionally require, a breach of confidentiality. As Beauchamp and Childress noted, “the therapeutic role may sometimes have to yield to ones role as citizen and as protector of the interests of others”.19 In general, however, circumstances requiring a breach of confidentiality are rare. 相似文献
976.
Cabergoline: an advance in dopaminergic therapy 总被引:2,自引:0,他引:2
977.
R A Blouin B A Hamelin D A Smith T S Foster W J John H A Welker 《Antimicrobial agents and chemotherapy》1992,36(3):632-638
In this open-label study, the disposition of fleroxacin in liver disease in 12 healthy male volunteers, 6 male cirrhotics without ascites (group A), and 6 male cirrhotics with ascites (group B) was evaluated. Fleroxacin (400 mg) was administered orally and intravenously to each subject in a random crossover fashion. Fleroxacin was completely absorbed and achieved similar peak concentrations in plasma in all three study groups (P greater than 0.05). The volume of distribution exceeded 1 liter/kg in healthy controls and was not affected by liver impairment (P greater than 0.05). Only group B demonstrated differences in the pharmacokinetic parameters evaluated: the systemic and renal clearances of fleroxacin and the renal clearances and clearances of the two major metabolites of fleroxacin formed, N-demethyl fleroxacin and fleroxacin N-oxide, were significantly lower and the half-lives of the parent drug and its metabolites were significantly longer in group B than in healthy controls and group A (P less than 0.05). The elimination of the two metabolites appeared to be formation rate limited in all three study groups. It was concluded from this study that a 50% reduction in the fleroxacin maintenance dose in patients with liver disease appears justified only in patients with ascites. However, no change in the fleroxacin loading dose is needed in patients with compromised liver function. 相似文献
978.
The introduction of laparoscopic inguinal hernia repair (LIHR) has been controversial. A questionnaire was sent to all general surgeons in New Zealand to document the early experience with LIHR and attitudes towards it. Of the 118 replies (response rate 55%). 74 were from laparoscopic surgeons. 26 of whom had performed 564 (201 public. 363 private) LIHR (23 bilateral) until January 1994. Only nine (35%) of these surgeons had assisted an experienced surgeon before performing an LIHR. and only four (15%) were supervised by an experienced surgeon during their first case. The transabdominal preperitoneal technique of LIHR was used by 14 (54%) surgeons. the extraperitoneal technique by eight (31%), and the tronsabdominal onlny technique by four (15%). There were 29 (5%) recurrences, 17 (3%) neuropathies. seven (1.2%) conversions, four (0.7%) miijor perforations. and one (0.17%) death. Of the 26 surgeons who performed LIHR, 20 (77%) were concerned about the absence of long-term results. 14 (54%) considered that the optimal technique had not been established. 13 (50%) were concerned about the unique complications associated with LIHR. 11 (42%) were less enthusiastic about performing LIHR than previously. 10 (38%) were doubtful about its advantages, and six (23%,) were uncertain about its future and considered that it should only be performed within the context of a controlled trial. This study highlights a number of issues that need to be addressed before the role of LIHR can be determined. 相似文献
979.
Frederick H. Epstein John P. Mugler James R. Brookeman 《Magnetic resonance in medicine》1994,31(2):164-177
A number of pulse sequence techniques, including magnetization-prepared gradient echo (MP-GRE), segmented GRE, and hybrid RARE, employ a relatively large number of variable pulse sequence parameters and acquire the image data during a transient signal evolution. These sequences have recently been proposed and/or used for clinical applications in the brain, spine, liver, and coronary arteries. Thus, the need for a method of deriving optimal pulse sequence parameter values for this class of sequences now exists. Due to the complexity of these sequences, conventional optimization approaches, such as applying differential calculus to signal difference equations, are inadequate. We have developed a general framework for adapting the simulated annealing algorithm to pulse sequence parameter value optimization, and applied this framework to the specific case of optimizing the white matter-gray matter signal difference for a T1-weighted variable flip angle 3D MP-RAGE sequence. Using our algorithm, the values of 35 sequence parameters, including the magnetization-preparation RF pulse flip angle and delay time, 32 flip angles in the variable flip angle gradient-echo acquisition sequence, and the magnetization recovery time, were derived. Optimized 3D MP-RAGE achieved up to a 130% increase in white matter-gray matter signal difference compared with optimized 3D RF-spoiled FLASH with the same total acquisition time. The simulated annealing approach was effective at deriving optimal parameter values for a specific 3D MP-RAGE imaging objective, and may be useful for other imaging objectives and sequences in this general class. 相似文献
980.
Ossification of the posterior longitudinal ligament: a report of nine cases in non-Oriental patients
John G. Heller M.D. Richard B. Johnston III M.D. Allan Goodrich M.D. 《Skeletal radiology》1994,23(8):601-606
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