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71.
72.
The past 30 years have witnessed a major paradigm shift in brain tumor research with the development of a wide variety of molecular  相似文献   
73.
Ambulatory blood pressure monitoring (ABPM) in adults is proving to be useful. The aim of this study was to determine if ABPM is accurate in the lower blood pressure range encountered in children and, equally important, whether it is acceptable to children. Thirty one children, between the ages of 6 and 18 years, were assessed using an ambulatory blood pressure monitor that uses an auscultatory method. Blood pressure was measured in the contralateral arm with a mercury sphygmomanometer and an oscillometric device at the beginning and end of the study for comparison. Over a blood pressure range of 90-130 mm Hg systolic and 40-80 mm Hg diastolic, a close agreement was found with the sphygmomanometer; the limits of agreement (+/- 2 SD) were 11.6 mm Hg for systolic blood pressure and 13.6 mm Hg for diastolic blood pressure. The bias was less than 1.0 mm Hg. The ambulatory device was worn by all patients for at least 16 hours with an average of 52 recordings per patient. The majority found the device comfortable to wear and were not woken from sleep.  相似文献   
74.
A boy, diagnosed as having Addison''s disease due to idiopathic atrophy of the adrenal glands at the age of 7 years, developed the first evidence of what was originally thought to be `Schilder''s disease'' at 8 years and 10 months. He died at 9 years and 11 months. There was a very striking family history of autoimmune disorders on the mother''s side. The clinical and pathological aspects of his case are outlined. Detailed studies of adrenal function during life showed a diminution in excretion of adrenal androgens and corticosteroids before therapy which was not evident from the 17-oxosteroid and 17-hydroxycorticosteroid assays in the resting state, though the initial diagnosis was based on the failure of ACTH to produce a rise in the 17-hydroxycorticosteroid excretion. No unusual or abnormal steroids were detected nor was there any disproportion between the androgen and corticosteroid excretion to suggest an adrenal enzyme deficiency. The biochemistry of the brain at necropsy revealed the changes expected in a demyelinating disorder, but the detection of abnormalities in the grey matter distinguished the condition from `Schilder''s disease'' in which the biochemistry of the grey matter is normal. There are 12 fully documented reports of boys with adrenocortical atrophy and diffuse cerebral sclerosis, and it is thought that this rare entity is inherited as an X-linked recessive characteristic. The two likely theories of causation involve either an error of metabolism common to the adrenal cortex and the brain, or the possibility that both the adrenal and brain pathology are due to an autoimmune disorder.  相似文献   
75.
76.
Purpose:We conducted a phase II multicentre study of gemcitabinein patients with anaplastic astrocytoma and glioblastoma multiforme at firstrelapse. Patients and methods:Patients with anaplastic astrocytoma orglioblastoma multiforme receiving a stable dose of steroids and ECOGperformance status 3 were eligible for this study at the time of firstrelapse. One adjuvant chemotherapy regimen was permissible. Patients receivedgemcitabine 1000 mg/m2 i.v. weekly × 3, repeated on afour-weekly cycle. Results:Of 20 patients enrolled, 15 were evaluable for response,19 for non-hematological toxicity and 18 for hematological toxicity. Sevenpatients had anaplastic astrocytoma (AA) and twelve glioblastoma multiforme(GBM). Age ranged from 28–71 years (median 50). Fifteen patientsdiscontinued therapy due to disease progression. The median number of cyclesadministered was 1 (range 1–11); only two patients received more thanthree cycles. Hematologic toxicity was acceptable and no grade 4 toxicity wasseen. One patient developed Pneumocystispneumonia and eventualpulmonary embolism; one died of gastric hemorrhage related to steroid therapy.No objective responses were seen. Nine patients had stable disease (medianduration 2.7 months, range 0.9–11.2). Conclusions:Gemcitabine given in this dose and schedule seemswell tolerated but is not active in patients with recurrent high-gradegliomas.  相似文献   
77.
The objective of this study was to ascertain the duration of tumor control and the toxicities of dose-intense myeloablative chemotherapy for patients with recurrent oligodendrogliomas. Patients with previously irradiated oligodendrogliomas, either pure or mixed, that were contrast enhancing, measurable, and behaving aggressively at recurrence were eligible for this study. Only complete responders or major partial responders (75 % reduction in tumor size) to induction chemotherapy--either intensive-dose procarbazine, lomustine, and vincristine or cisplatin plus etoposide-could receive high-dose thiotepa (300 mg/m2/day for 3 days) followed by hematopoietic reconstitution using either bone marrow or peripheral blood stem cells. Thirty-eight patients began induction chemotherapy and 20 (10 men, 10 women; median age 46 years; median Karnofsky score 80) received high-dose thiotepa. For the high-dose group, the median event-free, progression-free, and overall survival times from recurrence were 17, 20, and 49 months, respectively. Tumor control in excess of 2 years was observed in 6 patients (30%). Four patients (20%) are alive and tumor free 27 to 77 months (median, 42 months) from the start of induction therapy; however, fatal treatment-related toxicities also occurred in 4 patients (20%). Three patients died as a result of a progressive encephalopathy which, in 2 instances, was accompanied by a wasting syndrome; 1 patient died as a consequence of an intracerebral (intratumoral) hemorrhage. Fatal toxicities occurred in patients with pretreatment Karnofsky scores of 60 or 70. High-dose thiotepa to consolidate response was a disappointing treatment strategy for patients with recurrent aggressive oligodendroglial neoplasms, although several patients had durable responses. Moreover, as prescribed, high-dose thiotepa had significant toxic effects in previously irradiated patients, especially those with poorer performance status.  相似文献   
78.
Magnetic resonance imaging of benign mediastinal masses   总被引:1,自引:0,他引:1  
  相似文献   
79.
Tidwell  T; Guzman  G; Vogler  WR 《Blood》1981,57(4):794-797
The action of an alkyl-lysophospholipid (ALP), ET180CH3, on clonogenicity, 3H-TdR uptake, and cell numbers was tested in two human leukemic cell lines, HL60 and K562, and short-term human leukemic bone marrow cultures. ALP eliminated clonogenicity in HL60 but not in K562 cultures; 3H-TdR uptake and cell numbers were depressed at low concentrations of ET180CH3 in HL60, but not K562 cultures. The action of the lysophospholipid analog on human leukemic bone marrow short-term cultures at low concentrations was similar to its action on HL60 cultures; clonogenicity and 3H-TdR uptake were depressed, but cell numbers were not significantly affected. The demonstration of differential action of ALP on two cell lines should significantly simplify the investigation of the mechanism of the reported differential action of ET180CH3 on normal and leukemic cell membranes.  相似文献   
80.
The effect of heat stable and heat labile Escherichia coli enterotoxins or cholera toxin in combination with theophylline on net water, sodium and chloride and unidirectional sodium and chloride fluxes was examined in acute isolated loops of jejunum of weanling swine. The effect of heat stable enterotoxin in combination with theophylline was determined in loops located in the proximal jejunum, while combinations of theophylline and either heat labile enterotoxin or cholera toxin were studied in the distal jejunum. In each situation the addition of theophylline resulted in an additive rather than a synergistic increment of intestinal secretory activity. This study implies that the intestinal adenyl cyclase system and enterotoxin induced intestinal secretion may not be directly related in the swine small intestine.  相似文献   
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