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31.
Factor VIII exchange test experiments with hemophilia A plasmas were performed to find out how the results were affected by submitting plasmas and plasma mixtures to different incubation periods at 37 degrees C, heat precipitation, and ether extraction. The experiments led to the following results: 1. In plasma mixtures, frequently higher factor VIII activities are found than can be expected from the single activities of the used plasmas. Activity increases are factor-specific. 2. The component to be activated is in the hemophilic plasma; the activity-increasing agent is in the normal plasma. These results lead to the hypothesis that hemophilia A patients have sufficient quantities of inactive factor VIII, but it stays inactive for lack of the necessary activator. In normal plasma the activator is in balance or surplus to the inactive factor. By adding normal plasma, thus supplying free activator, the inactive factor VIII of hemophilia A plasma can, under suitable conditions, be developed into active factor VIII.  相似文献   
32.
In this review of 7,464 consecutive infants born at North Carolina Memorial Hospital, hemolytic disease from ABO incompatibility was found to be two to three times as common in black infants as in white infants. The statistical significance of the difference remained high as more restrictive criteria for ABO hemolytic disease were applied. ABO disease, serious enough to cause an indirect serum bilirubin of 15 mg/100ml or higher, had an incidence in black newborns as great as the incidence of Rh hemolytic disease in whites. In contrast, the general prevalence and severity of hyperbilirubinemia was not found to be higher in black newborns than in white infants. The difference cannot be attributed to differences in the prevalence of ABO blood groups between the two races. Policies of early discharge of newborns could be affected by the finding that ABO erythroblastosis is two to three times as common in black infants as in white infants.  相似文献   
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34.
The most prevalent microorganisms isolated from urine specimens of dogs (385) and cats (132) with clinical signs of urinary tract infections were Escherichia coli, Proteus spp., and Staphylococcus aureus. The results of quantitative urine-culturing methods showed 48.6% of the canine and 12.1% of the feline specimens had more than 10(5) organisms per ml of urine. The bacteria isolated appear to have a greater resistance to antibacterial agents than previously reported.  相似文献   
35.
"Zero-loop" of the molecular potential transformer of submitochondrial particles (SMP) is separated from the remaining electron transfer chain by rotenone, and its e.m.f. ET=0,003+RT/2F in [NADP X H] [NAD+]/[NADP+] [NAD X H] volts is used in the compensative method of measurement of the potential difference across the SMP membrane (delta USMP). The phospholipid membrane, measuring the concentration of the penetrating anions in the solution contained SMP, is used as "zero-indicators". This concentration drops monotonically with increase in delta USMP. Delta USMP is equal to ET when the addition of substrates of transhydrogenase reaction with definite ET does not change the potential across phospholipid membrane.  相似文献   
36.
An unusual form of left ventricular aneurysm affecting young Negroes has recently been described at the aortic or mitral valve ring; constitutional factors have been postulated. A 4-year-old Negro boy was observed with a left ventricular submitral aneurysm, probably one of the largest and one of the most calcified to be reported. Tuberculous lymphadenitis involving some of the mediastinal lymph nodes was found on postmortem examination; tuberculosis was believed to be a secondary contributing factor. A review of the literature disclosed only 5 other children with calcified left ventricular aneurysms, of which 2 were of the subvalvular type.  相似文献   
37.
We report here an experience with five patients, aged 58 to 70, suffering gangrene of the left colon after spontaneous inferior mesenteric artery occlusion. All cases were the result of arteriosclerosis; in two, small aortic aneurysms were present and might have been responsible for emboli to the inferior mesenteric artery. The dead bowel was resected in all patients; three patients survived. No primary anastomoses were done and they are not recommended. Because ligation of the patent inferior mesenteric artery has been done so often without ill effects during aortic surgery, the collateral circulation to the left colon can be considered excellent. Gangrene is therefore rare and requires major interference with collateral circulation by emboli or arteriosclerotic occlusion. The clinical symptoms and signs may be confusing.  相似文献   
38.
A commercially available recording of Northwestern University Auditory Test No. 6 (N.U. No. 6) produced by Auditec of St. Louis was evaluated in a series of four studies. Interlist equivalence of this version was initially investigated, and then normative intelligibility functions were developed using listerners with normal hearing. Intelligibility functions for the original version of N.U. No. 6. prepared by Northwestern University, were then derived, concurrently with functions of the Auditec version, using (1) a group of listeners with normal hearing; and (2) a group with sensorineural hearing loss. The results demonstrated good interlist equivalence for the Auditec version of N.U. No. 6. The comparative intelligibility functions for the Auditec and Northwestern versions of N.U. No 6 furthermore indicated a difference between the two recordings, but it was concluded that for clinical purposes the two versions may be considered equivalent.  相似文献   
39.
The distressing nature of laryngeal papillomatosis and lack of clinical progress in its treatment are reviewed. Presently accepted and investigative methods of therapy are reviewed with special attention being given to immune therapy. Support for the concept of a viral etiology is discussed and other etiologic agents considered. Known and possibly significant roles of wart virus antibodies are discussed and the importance of complex interplay between maternal and fetal immune systems explored as a possible explanation for some puzzling aspects of laryngeal papillomatosis. Finally, a proposed experimental design is outlined, the purpose of which is to provide a useful animal model to investigate immune changes in laryngeal papillomatosis, as well as effects of surgical or medical therapy.  相似文献   
40.
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