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71.
72.
This study investigated the effect of a twice-weekly, six-month progressive walking program on 80 healthy women aged 60 to 70 years. Aerobic fitness, blood pressure, skinfold thickness, spirometric variables, and activity profile were studied. No significant differences existed between the training group (TG) and the control group (CG) at the commencement of the study. However, after 26 weeks of training, the TG registered significantly lower heart rates than the CG, both at rest (p = .019) and during the five to six minutes of an ergometer work test (p = .003). A Mann-Whitney U test on the difference scores (26 weeks-0 week) indicated higher scores for the TG compared with the CG for Maximum Current Activity (p = .001) and Normative Impairment Index (p = .002), which are both components of the Human Activity Profile. These data suggest that adherence to a low-frequency training program can elicit positive physiologic changes in elderly women. Furthermore, increased habitual activity patterns are likely to be indicative of improvements in functional ability, lifestyle, and independence.  相似文献   
73.
A statistical analysis of 193 patients with thyroid carcinoma encountered at Vanderbilt University Hospital from 1925 to 1974 is reported, from which the following conclusions are drawn: (1) Papillary thyroid carcinoma is an extremely favorable lesion that when grossly limited to one thyroid lobe can usually be managed successfully by ipsolateral total lobectomy. (2) Cervical lymph node enlargement in patients with papillary carcinoma requires lymph node dissection. When feasible, the spinal accessory nerve should be preserved. (3) Failure to cure papillary and follicular thyroid carcinoma is influenced by advanced age, inadequate local extirpation, and unresectability of the carcinoma. (4) Prophylactic lymph node dissection is rarely indicated in the treatment of follicular carcinoma. A new isotope scanning procedure, developed at Vanderbilt University Hospital, promises to be helpful in preoperatively differentiating benign from malignant solitary thyroid nodules.  相似文献   
74.
The technique for the isolation of mutants was applied to establish highly clonogenic cells from a fibrosarcoma (FSA) that had an extremely poor growth capacity in vitro (10(-6)--10(-7) of surviving fraction of cells). After consecutive clonings, the surviving fraction of cells increased to 1--5 X 10(-1), whereas that of the ordinarily maintained culture remained at a low level. Selected clones were analyzed in vitro and/or in vivo. The results indicated that the FSA was composed of heterogeneous cells or cells having a potential variability in cloning ability in vitro, metastatic ability in vivo [lung colony-forming efficiency (LCFE)], and DNA content. The relatively high DNA content of one of the clones, FSA 1233, continued after growth in vivo or in vitro, indicating its hereditary nature. FSA 1233 was also demonstrated to have a lower LCFE when the cell suspension was made from a tumor rather than from a culture in vitro. The difference of surviving fractions between the cells in the two conditions was not enough to explain the difference in LCFE's between them. These cells could grow under either in vitro or in vivo conditions and could be made readily into single-cell suspensions. The cells are, therefore, available as a system for analysis of the response of cells in vitro after in vivo treatment with various agents.  相似文献   
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In a retrospective study, local control of the primary tumor in 498 squamous cell carcinomas of the oral cavity and oropharynx was analyzed with respect to initial tumor volume, total dose after normalization for variations in fraction size, and to overall treatment time. Primary tumors were grouped into 4 sites, tongue (175), oral cavity including floor of mouth, faucial pillar, soft and hard palate and gingiva (210), tonsil (72) and buccal mucosa (41). Total doses of 60Co irradiation ranged from 30 Gy to 72 Gy, overall treatment times from 15 to 80 days and dose per fraction from 1.8 to 6 Gy. The large number of patients and diversity of dose fractionation patterns permitted assessment of the independent contributions to treatment outcome of stage, fraction size and overall treatment duration. The following conclusions were drawn: (1) Overall treatment time influenced strongly the probability of local tumor control. Over the interval of about 30-55 days used in treating most of this series of patients, an increase of 60 cGy per day, on average, was required for a constant control rate. (2) The increase in dose was attributed to accelerated tumor clonogen growth rate. Such accelerated growth could be a major determinant of failure in protracted regimens. (3) The accelerated rate of regrowth was similar for all tumor sites and stages. (4) The dose for tumor control was relatively independent of variations in fraction size within a range of about 1.6 Gy to 3 Gy: the alpha/beta value in the linear quadratic isoeffect equation was at least 15 Gy. (5) Local control at the primary site required an average of about 3 Gy more for each increase in T stage. This increase most likely reflected an increased number of tumor clonogens, not a decreased tumor cell radiosensitivity. (6) The probability of control at the primary site was less likely if lymph nodes were positive, but this association was only shown to be statistically significant for primaries classified here as oral cavity and oropharynx, not tonsil, tongue or buccal mucosa. (7) After allowing for differences in treatment parameters, especially for heterogeneity in overall treatment times, tumor control probability increased steeply with increase in total dose. (8) A general principle of radiotherapy, at least for squamous carcinomas of head and neck, should be to deliver the desired fractionated dose regimen without unnecessary interruptions and in the shortest time compatible with no reduction in dose below that tolerated by the late-responding normal tissues.  相似文献   
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Intravascular tumors: transvenous biopsy   总被引:1,自引:0,他引:1  
Withers  CE; Casola  G; Herba  MJ; Viloria  J 《Radiology》1988,167(3):713-715
A technique is described for transfemoral biopsy of intravenous tumors. Positive results were obtained at biopsy in three patients who had an intraluminal mass in the inferior vena cava and in one patient with a mass in the iliac vein. Transvenous biopsy is helpful in obtaining a histologic diagnosis and provides an alternative method to surgery or percutaneous transabdominal needle biopsy.  相似文献   
80.
31P nuclear magnetic resonance study of the brain in Alzheimer's disease   总被引:1,自引:0,他引:1  
The histopathological hallmarks of Alzheimer's disease have long been considered to be neurofibrillary tangles (NFT) and neuritic (senile) plaques (SP). Neither of these structures, however, are unique to Alzheimer's disease, and both probably represent end-stage markers of the disorder. NFT have been demonstrated in many disorders; SP occur in small numbers with normal aging. Evidence is presented for elevation of phosphomonoesters (PME) in Alzheimer's brain compared to non-Alzheimer's diseased controls and normal controls. The PME detected by 31P nuclear magnetic resonance (NMR) spectroscopy of autopsy brain are predominantly anabolic precursors of membrane phospholipids. Elevated PME could be secondary to a metabolic block at the rate-limiting enzyme in membrane phospholipid synthesis, which is cytidine triphosphate (CTP): phosphocholine (or phosphoethanolamine) cytidyltransferase (EC 2.7.7.15). Elevated PME could also be secondary to decreased breakdown of PME by phospholipase D activity. Since CTP: phosphocholine cytidyltransferase is inactivated by phosphorylation and since there is independent evidence for hyperphosphorylation of tau and MAP-2 proteins in AD brain, enhanced protein kinase activity could be a common factor. Preliminary evidence suggests that PME could interact with N-methyl-D-aspartate receptors and potentially act as false neurotransmitters. Further studies will be needed to investigate these possibilities.  相似文献   
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