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991.
992.
Peripheral blood blast cell progenitors in human preleukemia 总被引:1,自引:0,他引:1
Progenitors of blast cell colonies have been identified in acute leukemia. The peripheral blood of 18 of 25 patients with preleukemic states yielded low numbers of blast cell colonies, and the colony- forming cells were in an active proliferative state when assessed using short-term exposure to tritiated thymidine. The clinical significance of blast cell colonies is uncertain, but we suggest that further analysis of this cultural abnormality may lead to a better understanding of mechanisms and management in preleukemia. 相似文献
993.
Thoracic disk herniation: MR imaging 总被引:3,自引:0,他引:3
The authors undertook a retrospective study to assess the role of magnetic resonance (MR) imaging in thoracic disk herniation. The initial MR images were interpreted independently of other findings. These interpretations were compared with the findings of plain and computed tomography (CT) myelography and surgery, when available. Sixteen thoracic disk herniations were confirmed with plain and CT myelography and/or surgery. Plain myelography was performed on 14 patients and showed focal ventral filling defects in nine. Results of CT myelography were equivalent to those of MR imaging with three pulse sequences (sagittal T1 and T2 weighted, axial T1 weighted) in the identification of all the abnormal levels. In two patients, the signal from the herniated disk was so low on all sequences that thoracic disk herniation had to be inferred from the mass effect on the spinal cord. Precise location of the abnormal level with body coil MR images was achieved in six of 13 patients. 相似文献
994.
A study of complications associated with paraaortic irradiation was undertaken in patients with uterine cervical cancer who had not undergone prior lymphadenectomy. Between 1975 and 1984, 29 highly selected patients received paraaortic irradiation as part of their definitive treatment for cervical carcinoma. Paraaortic fields were irradiated to a total dose of 4,200-5,000 rad (42-50 Gy), in fractions of 150-180 rad (1.5-1.8 Gy). An anteroposterior-posteroanterior technique was generally used. All fields were treated every day. There were no instances of small-bowel obstruction or other major complications, surgical procedures, or deaths caused by paraaortic irradiation. Eleven patients (38%) have no evidence of recurrent disease 23-120 months after completion of therapy. Paraaortic irradiation was well tolerated in this patient group without prior staging lymphadenectomy. Thus, in selected patients and with appropriate techniques, paraaortic irradiation for cervical carcinoma may be used with relative safety. 相似文献
995.
Williamson JR; Gardner RA; Boylan CW; Carroll GL; Chang K; Marvel JS; Gonen B; Kilo C; Tran-Son-Tay R; Sutera SP 《Blood》1985,65(2):283-288
This study was undertaken to determine whether diabetes alters the viscoelastic properties of erythrocytes. The oldest and youngest 10% fractions of circulating red cells were separated by centrifugation of freshly drawn blood obtained from ten diabetics with disease of one to 20 years' duration and from an equal number of age- and sex-matched control subjects. Cells from each fraction were suspended in phosphate- buffered saline, and their rheologic behavior was examined in a rheoscope. The elongation of cells, the percentage of cells that tank- treaded in response to shear stress, tank-treading frequency, and the rate of recovery of cell shape upon cessation of shear stress were determined in the oldest and youngest 10% of cells for diabetics as well as for controls. All four parameters were virtually identical for diabetics and controls. Additional aliquots of cells were taken for assessment of nonenzymatic glucosylation of hemoglobin and cell membrane protein. The absence of any measurable difference in rheologic behavior of cells from diabetic and control subjects, despite substantial differences in nonenzymatic glucosylation of hemoglobin and cell membrane proteins, suggests that the magnitude of glucosylation observed in these cellular constituents does not alter the viscoelastic properties of the cells. The implication of these observations is that microvascular complications of diabetes are not attributable to altered deformability of red cells. 相似文献
996.
Frith has proposed that symptoms of alien control in schizophrenia result from a defect in a metarepresentational process leading to a failure to properly monitor self-willed intentions and actions. To examine this hypothesis, a group of 40 schizophrenic patients, all meeting DSM-III-R criteria, and rated for current symptoms on the basis of a detailed clinical interview, were compared with 36 non-patient controls, using a battery of tests which included measures of self-monitoring, general cognitive function and attention. In comparison with controls, patients were impaired on two tests of self-monitoring. These differences were preserved when measures of current IQ, attention, and recognition memory were entered as covariates. Amongst patients, self-monitoring performance was related to the severity and extent of positive symptoms. These findings provide further experimental support for the proposal that positive symptoms of schizophrenia arise as a result of deficiencies in self-monitoring. 相似文献
997.
998.
Hellewell JS 《CNS drugs》2002,16(7):457-471
The subjective experience of patients with schizophrenia who are receiving antipsychotic medication has been a neglected research area, as has the satisfaction of patients with their drug treatments. This is unfortunate, as satisfaction with treatment appears to be related strongly to the readiness of patients to take their medication as prescribed, and thereby to outcome. Patients' perceptions of their treatment do not appear to be related strongly to severity of illness or symptom ratings, although there are associations between perceptions of treatment and adverse effects. Surveys of patient experience with typical antipsychotics have tended to indicate high levels of dissatisfaction and perceived adverse effects. There have been a number of surveys of patients' perceptions of treatment with the atypical antipsychotics. These tend to accord with the expectation that a relative freedom from adverse effects with the atypical antipsychotics will be reflected in enhanced levels of satisfaction and perceived well-being. In general, these studies share a number of weaknesses, including small sample sizes, bias in selection of respondents, open treatment and lack of suitable comparator groups. In addition, many have adopted a cross-sectional, rather than longitudinal, approach and have relied on nonvalidated and perhaps idiosyncratic rating measures. Recently, there have been studies of better methodological quality. These, too, have indicated that patients regard the newer treatments more positively than the older regimens. In addition, there is now evidence that the various new-generation antipsychotics may be evaluated differently by patients. 相似文献
999.
1000.