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51.
Cytogenetic studies were done on 18 patients with myelofibrosis or the closely related syndrome, undifferentiated myeloproliferative disorder (MPD). Clones of cells with chromosome abnormalities were demonstrated in the blood of eight individuals, including two with a history of radiation therapy and two with "acute myelofibrosis". Trisomy 8 was present in the latter two patients, but otherwise, there was no consistent cytogenetic pattern or correlation with specific hematologic findings. Sixteen of these patients have been followed for more than 1 year or until death; none has progressed to leukemia. The results indicate that chromosome abnormalities are relatively common in this disorder, but as with polycythemia vera, and unlike some other "preleukemic" states, the aberrant clones in myelofibrosis do not appear to indicate that clinical leukemia is imminent.  相似文献   
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Thirteen autistic children were compared to 13 normal children matched to them in mental age, on performance of a visual discrimination task. Form, color, and size were relevant and redundant cues. The groups did not differ significantly in mean trials to reach criterion or in breadth of learning, and both groups increased their breadth of learning after 50 trials of overtraining. Form was preferred to color and size by both autistic and normal children. Within each group, rank on mental age was highly correlated with rank in breadth of learning. Verbal and nonverbal autistic children did not differ in breadth of learning or in dimensional preference. Even nonverbal autistics equaled the performance of their normal controls. Our results suggest that overselective attention is better understood as part of a general developmental lag in cognition in autistic children than as a specific deficit underlying psychotic behavior.  相似文献   
54.
Over a 12-year period, 43 operations were performed on 40 patients for correction of the subclavian steal syndrome. Eleven of these patients also underwent endarterectomy for coexisting carotid artery disease. There were 16 transthoracic procedures and 27 transcervical procedures. Graft failure in two patients was corrected by a second operation. There was one early death and one late death. The remaining 38 patients have been carefully studied for up to 12 years, with an average follow-up period of 60 months. These 38 patients have remained asymptomatic and their revascularization procedures have remained functional, as determined by blood pressure determinations in the involved extremity and, in some cases, by arteriography.  相似文献   
55.
The cost of managing 114 adult haemophiliacs in the west of Scotland was assessed for the period 1 March 1971 to 28 February 1974. Altogether 23 of them (20%) accounted for 80% of the resources used. The cost of hospital treatment of these patients during the period was compared with the predicted cost of home treatment, given the availability of freeze-dried factor VIII concentrate in sufficient amounts. We calculate that adequate on-demand home treatment would cost only 16% more than the present treatment, which is substantially less efficient.  相似文献   
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The importance of the adrenal hormones in the lipogenic responses to meal-feeding or starvation-refeeding was studied. In experiment 1, intact or adrenalectomized (ADX) rats were either ad libitum-fed or meal-fed a 65% glucose diet for 21 days or until moribund (ADX rats only). Serum glucose and electrolytes (Ca++, Mg++, Na+, K+), hepatic glycogen and glucose-6-phosphate dehydrogenase (G6PD) and malic enzyme (ME) were determined. ADX rats died within 10 days after the initiation of meal-feeding and were hypoglycemic with low liver glycogen levels and low enzyme activities. No differences in serum electrolytes were observed. In the second experiment, ADX and intact rats of varying initial weights were weight paired and meal-fed. When the ADX rat died, his intact control was killed and both carcasses assayed for fat content. Heavier rats with presumably more carcass fat survived meal-feeding longer than the lighter rats. Rats died when they had lost all but 2 to 3 g carcass lipid. In experiments 3 and 4, ADX and intact rats were subjected to starvation-refeeding. In experiment 4, additional ADX groups were given supplemental doses of cortisol (0.75 mg/kg, subcutaneous, 2 times daily) during either the starvation period, the refeeding period or during both periods. The activities of hepatic G6PD and ME were determined as well as the levels of liver lipid in experiment 4. Intact starved-refed rats had the usual enzyme overshoot, whereas ADX starved-refed rats did not. Cortisol-treated ADX starved-refed rats had as great an enzyme overshoot as the intact rats and as great an increase in liver lipid. These results suggest that ADX rats die when meal-fed the glucose diet, because they are unable to store sufficient metabolic fuel for use during the starvation phase of the meal-feeding cycle. Further, the results show that glucocorticoids are required for the induction of de novo enzyme synthesis.  相似文献   
59.
During blue-green algal blooms, other algae can be completely suppressed. This ability of blue-green algae to suppress other algae may be determined by the abailability of iron. Iron deprivation induces the production of hydroxamate chelators, which appear to be the agent suppressing other algae.  相似文献   
60.
Individually interviewed 50 male undergraduates for 20 min about procedures used in confronting decision-making situations. The interviewer disclosed experiences, attitudes, and feelings similar to those revealed by the students 0, 2, 4, 8, or 12 times during the interviews. An intermediate number of interviewer self-disclosures resulted in significantly more students returning for a 2nd interview than did few or many self-disclosures. Results suggest that the use of a moderate number of interviewer self-disclosures may be an effective means of increasing counselor attractiveness and client approach responses to the counselor. (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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