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91.
92.
This trial tests the hypothesis that confirming a clinical diagnosis of familial hypercholesterolemia (FH) by finding a genetic mutation reduces patients' perceptions of control over the disease and adherence to risk-reducing behaviors. Three hundred forty-one families, comprising 341 hypercholesterolemia probands and 128 adult relatives, were randomized to one of two groups: (a) routine clinical diagnosis; (b) routine clinical diagnosis plus genetic testing (mutation searching in probands and direct gene testing in relatives). The main outcome measures were perceptions of control over hypercholesterolemia, adherence to cholesterol-lowering medication, diet, physical activity, and smoking. There was no support for the main hypothesis: finding a mutation had no impact on perceived control or adherence to risk-reducing behavior (all P-values > 0.10). While all groups believed that lowering cholesterol was an effective way of reducing the risk of a heart attack, participants in whom a mutation was found believed less strongly in the efficacy of diet in reducing their cholesterol level (P = 0.02 at 6 months) and showed a trend in believing more strongly in the efficacy of cholesterol-lowering medication (P = 0.06 at 6 months). In conclusion, finding a mutation to confirm a clinical diagnosis of FH in a previously aware population does not reduce perceptions of control or adherence to risk-reducing behaviors. The pattern of findings leads to the new hypothesis that genetic testing does not affect the extent to which people feel they have control over a condition, but does affect their perceptions of how control is most effectively achieved. Further work is needed to determine whether similar results will be obtained in populations with little previous awareness of their risks.  相似文献   
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94.
W C Lam  K S Lam  D J Lee  M J O''Neill 《Radiology》1983,149(1):322-323
A simple method of fabricating photon beam tissue compensators is described. A plaster cast of the patient's surface contours is partially immersed in a mixture of India ink and water to obtain a topographic map relative to a reference plane which is perpendicular to the photon beam. The contours are photographed, and successive contours corresponding to different missing tissue thicknesses are used to fabricate a compensator from lead sheets cut to the same shape with the proper magnification.  相似文献   
95.
Effect of radiation and contrast media on chromosomes. Preliminary report   总被引:1,自引:0,他引:1  
Adams  FH; Norman  A; Mello  RS; Bass  D 《Radiology》1977,124(3):823
  相似文献   
96.
97.
J A O''Neill  Jr  M T Stahlman    H C Meng 《Annals of surgery》1975,182(3):274-279
Fifty-two premature, low birth weight infants presented mainly in the first week of life with sudden manifestations of intestinal ileus and an x-ray picture of pneumatosis intestinalis. Twenty-two of 32 patients treated with gastric decompression, antibiotics, intensive supportive therapy and intravenous hyperalimentation survived. Twenty other patients had progression of their disease and required operation. Twelve of these patients survived. Review of this material indicated that some medically treated patients might have survived if they had been operated upon. Indications for operation included free perforation and clinical signs of deterioration. Abdominal physical findings and x-rays were not reliable except as signs of far advanced pathology. Confirmation of ascites by paracentesis and gram stain of fluid was helpful when present. If patients were adequately treated and then developed sudden hyponatremia or progressive acidosis, they invariably had gangrenous bowel and required operation. The most striking finding was that a sudden, profound drop in the platelet count to levels below 100,000 reliably predicted the presence of gangrenous bowel and the need for operation. Other clotting studies indicated that disseminated intravascular coagulation is an important accompaniment of NNE with the complication of bowel gangrene prior to perforation. Gastrostomy and resection of involved bowel with staged anastomosis proved to be the most successful form of surgical management. Overall suvival was 66 per cent.  相似文献   
98.
Post-transfusion purpura: a heterogeneous syndrome   总被引:3,自引:0,他引:3  
Zeigler  Z; Murphy  S; Gardner  FH 《Blood》1975,45(4):529-536
Three new patients with post-transfusion purpura (PTP) are described. As the manifestations in two differ significantly from those of previously reported cases, they serve to expand the definition of this syndrome. Although all 14 previously reported cases have occurred in Pl- A1-negative females, one of our patients was a Pl-A-negative male. Moreover, a female whose postrecovery platelets possessed the Pl-A1 antigen is described. Antiplatelet antibody activity was detected in all three patients by the 51Cr release test; in contrast, only one reacted in the complement (C) fixation assay. Serum obtained during the acute episode from the PlA1-positive patient reacted against platelets from four of 11 normals by C fixation and against platelets from 48 of 53 normals by 51Cr release, including five of nine Pl-A1-negative platelet samples. This case represents the first instance of PTP in which the platelet isoantibody was not specifically directed against the Pl-A1 antigen. These observations suggest that PTP may be a more heterogeneous disorder than previously realized.  相似文献   
99.
Two patients with oculomotor neuropathy demonstrated passive ocular proptosis. In both instances, there was no evidence of a pathological process exerting a vector of force through the orbital opening. The proptosis is caused by a combination of the loss of the normal backward force exerted by the ocular recti muscles and the presence of a small anteriorly directed force exerted by the ocular obliques. Computerized tomography of the orbital and retro-orbital regions was of value in establishing the diagnosis and excluding orbital disease in one patient. The role of computerized tomography in the evaluation of the patient with ocular proptosis is discussed.  相似文献   
100.
BACKGROUND: The FDA has approved the storage of frozen RBCs at -80 degrees C for 10 years. After deglycerolization, the RBCs can be stored at 4 degrees C for no more than 24 hours, because open systems are currently being used. Five laboratories have been evaluating an automated, functionally closed system (ACP 215, Haemonetics) for both the glycerolization and deglycerolization processes. STUDY DESIGN AND METHODS: Studies were performed at three military sites and two civilian sites. Each site performed in vitro testing of 20 units of RBCs. In addition, one military site and two civilian sites conducted autologous transfusion studies on ten units of previously frozen, deglycerolized RBCs that had been stored at 4 degrees C in AS-3 for 15 days. At one of the civilian sites, 10 volunteers received autologous transfusions on two occasions in a randomized manner, once with previously frozen RBCs that had been stored at 4 degrees C in AS-3 for 15 days after deglycerolization and once with liquid-preserved RBCs that had been stored at 4 degrees C in AS-1 for 42 days. RESULTS: The mean +/- SD in vitro freeze-thaw-wash recovery value was 87 +/- 5 percent; the mean +/- SD supernatant osmolality on the day of deglycerolization was 297 +/- 5 mOsm per kg of H(2)O, and the mean +/- SD percentage of hemolysis after storage at 4 degrees C in AS-3 for 15 days was 0.60 +/- 0.2 percent. The paired data from the study of 10 persons at the civilian site showed a mean +/- SD 24-hour posttransfusion survival of 76 +/- 6 percent for RBCs that had been stored at 4 degrees C for 15 days after deglycerolization and 72 +/- 5 percent for RBCs stored at 4 degrees C in AS-1 for 42 days. At the three sites at which 24-hour posttransfusion survival values were measured by three double-label procedures, a mean +/- SD 24-hour posttransfusion survival of 77 +/- 9 percent was observed for 36 autologous transfusions to 12 females and 24 males of previously frozen RBCs that had been stored at 4 degrees C in AS-3 for 15 days after deglycerolization. CONCLUSION: The multicenter study showed the acceptable quality of RBCs that were glycerolized and deglycerolized in the automated ACP 215 instrument and stored in AS-3 at 4 degrees C for 15 days.  相似文献   
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