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71.
A family is described in which the mother and 2 of the 5 children had Felty's syndrome, a pattern of inheritance suggesting a dominant defect and one which has not previously been reported. The family is also of interest in that the other sib had rheumatoid arthritis.  相似文献   
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Fixation of prosthetic joint components into bone is influenced by the degree of mechanical interdigitation of the acrylic into cancellous interstices. The rheology of polymerizing polymethylmethacrylate was studied by pressurizing acrylic bone cement with a piston apparatus to produce flow into cylindrical cavities one to 3 mm in diameter. The acrylic penetration per unit of applied pressure increased with increasing cavity diameter. This suggests that greater penetration should occur in cancellous bone containing larger interstitial cavities. More than one-half (64 %) of the filling observed in our experiments took place within the first second of pressure application. Short duration, high level pressure pulses are the most effective means to achieve maximum penetration. Clinically, this is accomplished by vigorous finger packing. The cement should be pressurized as early as possible within the rasped cavity (immediately after dough stage if possible). The depth of penetration for 4-minute pressurization averaged three times that for 6 1/2-minute pressurization for the range of hole sizes and pressure levels tested.  相似文献   
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Twelve patients with predominantly obstructive type sleep apnea underwent cardiac catheterization, hemodynamic monitoring, and arterial blood gas analysis during wakefulness and sleep. Abnormalities during wakefulness included systemic hypertension in four of 12, exercise-induced mild pulmonary hypertension in five of 12, and alveolar hypoventilation in one. During sleep nine patients had cyclic elevations of arterial pressure with each apneic episode, exceeding 200 mm Hg systolic in three of 12. Pulmonary artery pressures increased in 10 of 12, exceeding 60 mm Hg systolic in five. Marked degrees of hypoxemia (arterial P02, less than 50 mm Hg in eight of 12) and moderate hypercapnia with respiratory acidosis were associated with these hemodynamic changes. Cyclic upper airway obstruction during sleep may result in hypercapnia, acidosis, and pronounced hypoxemia, which can lead to hemodynamic abnormalities during sleep. Sustained pulmonary hypertension and possibly systemic hypertension may follow. Tracheostomy is an effective therapy and is recommended to symptomatic patients who have predominantly obstructive apnea but no relievable anatomic cause of upper airway obstruction.  相似文献   
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Attempted to show that false recognition errors would be more frequently elicited by children's personal associates to a set of target words than by associates based on peer norms; Ss were 80 White middle-class 2nd and 5th graders (mean ages, 7.6 and 10.6 yrs, respectively). In Session 1 Ss gave oral associations to 34 words. In the 1st phase of Session 2, target words were each read aloud once and Ss were required to memorize them; in the 2nd phase Ss worked for 5 min on a maze task to prevent rehearsal; and in the final phase, a 40-item recognition list was read. Ss determined whether a word was one they had been asked to remember. As predicted, responses occurred with decreasing frequency to target, personal, peer, and control words. Consistent with the expectation that personal associates would more frequently elicit false recognition errors than would peer associates, the difference between personal and control responses was larger than the difference between peer and control. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
78.
Children's behavior toward adults who differed from them along 2 dimensions was examined from a developmental perspective. A total of 80 White kindergartners and 4th graders were tested individually by either a Black or a White female adult who either was or was not seated in a wheelchair. Three kinds of behavior toward the adult were measured: physical distancing, imitation, and helping. On the basis of previous findings, it was predicted that children at both age levels would show more physical avoidance, less imitation, and less helping in the presence of other-race and handicap cues, as compared with own-race and nonhandicap cues. On all 3 types of behavior, the White E was favored over the Black E in both the wheelchair and nonwheelchair conditions. In addition, there were interaction effects involving race, handicap, age, and sex that suggest the operation of complex developmental processes in the formation of attitudes toward different types of stigmatized individuals. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
79.
Investigation of the serum of three patients with positive antibody detection tests demonstrated the cause in each to be an antibody against chloramphenicol, a bacteriostatic agent used in commercial red blood cell reagents. Washing of these red cells prior to use prevented agglutination. All three examples of anti-chloramphenicol antibody were IgM and were in low titer when tested at room temperature and 37 C in saline. Two of the antibodies bound complement. The possibility of an antibody to an ingredient of the commercial preservative solution should be considered if problems are encountered in tests with unwashed commercial red blood cell reagents.  相似文献   
80.
Six cases of posterior cervical fusion with rib grafts in children are reported. Four of the children had sustained cervical spine injuries in accidents, and two had congenital absence of the odontoid. Three-level fusions (C1-3) were done in four children, and four-level fusions (C1-4) in two. One child died of unrelated causes 3 months after the operation. The other five children have been followed for 5 to 13 years. All are doing well and each has a remarkably supple, stable neck and no neurological deficit.  相似文献   
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