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61.
Oculocutaneous albinism   总被引:2,自引:0,他引:2  
Oculocutaneous albinism represents a group of inherited skin disorders characterized by a generalized reduction of cutaneous, ocular and pilar pigmentation from the time of birth. Oculocutaneous albinism types 1 and 2 are the most common, but several other types have been described. A defect in the melanin synthesis pathway, resulting in reduced formation of melanin, is responsible for oculocutaneous albinism. Aetiology, clinical manifestations, diagnosis and management are discussed.  相似文献   
62.
The authors report 2.5 years' experience with the use of cytomegalovirus (CMV)-seronegative blood components for the prevention of primary CMV infection after allogeneic marrow transplantation from seronegative marrow donors to 104 CMV-seronegative patients. Patients and blood donors were screened for CMV-seronegativity by a combination of passive latex agglutination, complement fixation, and indirect hemagglutination CMV antibody screening methods. Changes in blood banking procedures necessary to provide CMV-seronegative components are detailed. Providing CMV-seronegative components was a considerable undertaking; a mean, per patient, of 19 units of red cells and 105 units of platelets was required. Twenty percent of the platelet support was provided by family members and 80 percent by volunteer donors. CMV-infection was eliminated in all but one patient not considered infected at the time of transplantation. The capability to provide CMV-seronegative components depends on an adequate supply of seronegative donors, a sensitive and practical screening method for CMV antibody, a major commitment by the blood bank, and close communication between the blood bank and the patients' physicians.  相似文献   
63.
Elastic recoil of the vessel wall is a common cause of failure of percutaneous transluminal angioplasty in renal arteries. To oppose such recoil, balloon-expandable metal stents were implanted in artificially stenotic renal arteries in pigs and normal renal arteries in dogs and pigs. The stents were then examined angiographically and histologically at regular intervals. All stents were completely covered with endothelialized neointima in 3 weeks. There was no difference in intimal thickness between the stenotic and nonstenotic renal arteries. A large stent diameter and a large open or nonmetal surface may cause less intimal hyperplasia, but nonturbulent, fast arterial flow is probably the most important factor in ensuring long-term patency of the vessel.  相似文献   
64.
65.
Badami  JP; Baker  RA; Scholz  FJ; McLaughlin  M 《Radiology》1986,158(1):175-177
A group of 228 consecutive patients undergoing metrizamide myelography was prospectively evaluated for postprocedure symptoms. The observed prevalence of these symptoms concurs with previously reported inpatient studies, with the most common sequelae being exacerbation or onset of spine or extremity pain, headache, nausea, and paresthesia. Limitation of administered dose of metrizamide in lumbar myelography may slightly reduce the occurrence of common symptoms, but withdrawal of contrast medium at the completion of examination had no impact on their occurrence. There was a higher occurrence of paresthesia in cervical myelography, but otherwise there was no significant difference in symptoms between cervical and lumbar studies. Outpatient metrizamide myelography can be performed with relative safety with the potential for significant cost savings.  相似文献   
66.
Nyberg  DA; Filly  RA; Filho  DL; Laing  FC; Mahony  BS 《Radiology》1986,158(2):393-396
Simultaneous sonography and quantitative serum human chorionic gonadotropin (HCG) levels from 126 women with threatened abortion were compared. Of 56 women with normal outcome, 39 (70%) had a gestation sac greater than or equal to 5 mm in mean sac diameter, and in each case the HCG level was 1,800 milli-international units (mIU/ml) or greater. The serum HCG levels strongly correlated with the gestation sac sizes to a mean sac diameter of 25 mm. Of 70 abnormal pregnancies, 31 demonstrated a gestation sac. Of these, 20 women (65%) had disproportionately low HCG levels relative to sac size, including 12 in whom the HCG level was less than 1,800 mIU/ml. One woman with an early molar pregnancy had a disproportionately elevated HCG level. Correlation of sonograms with a simultaneous measurement of serum HCG level is a useful method for evaluating threatened spontaneous abortion. A disproportionately low HCG level relative to gestation sac size is evidence for an abnormal pregnancy.  相似文献   
67.
Role of point A in the era of computerized dosimetry   总被引:1,自引:0,他引:1  
Potish  RA; Gerbi  BJ 《Radiology》1986,158(3):827-831
  相似文献   
68.
Beckmann  CF; Roth  RA; Luedke  MD 《Radiology》1986,159(3):643-645
In 44 patients with one or more calculi in the upper two-thirds of the ureter, single-stage percutaneous nephrolithotomy was performed through a middle or upper calyceal nephrostomy after cystoscopic placement of an occlusion balloon catheter distal to the calculus; in 42, the procedure was successful. The occlusion balloon catheter permitted retrograde opacification of all systems for enhanced renal puncture. In the last 30 patients an attempt was made either to push the calculus upward mechanically or to flush it upward into the renal pelvis with carbon dioxide or dilute contrast material. This was successful in 24 of these patients. Prior overnight occlusion of the ureter by means of ureteral dilatation further facilitates dislodgment of the calculus, which was successful in 12 of 13 patients.  相似文献   
69.
Suicidal ideation and behaviour are common among inmates. Anger is found at exaggerated levels and has been associated with suicidal ideation and behaviour in inmate samples suggesting its possible salience in the prediction of suicide. The study investigated relationships between anger, psychological distress, and self-harm/suicidal ideation among inmates. The principles of Ecological Momentary Assessment were considered and a structured self-assessment diary was utilised to examine relationships between the variables of interest. Participants completed a structured self-assessment diary for six consecutive days which included momentary ratings of items describing psychological states of concurrent affects, thoughts, and appraisals related to anger, psychological distress, and self-harm/suicidal ideation. Psychometric assessment measures were also conducted. Temporal associations between predictors and outcomes were investigated. Multilevel modelling analyses were performed. Increased anger was significantly associated with concurrent high levels of self-harm ideation in inmates, when controlling for depression and hopelessness. Temporal analyses also revealed that anger at one time point did not predict suicidal ideation at the next time point. Elucidating the temporal nature of the relationship between anger, psychological distress, and self-harm/suicidal ideation has advanced understanding of the mechanisms of suicidal behaviour, by demonstrating an increased risk of suicide when a male inmate is angry.  相似文献   
70.
The authors describe their experience with methyl tertiary butyl ether (MTBE) in a larger series of patients than previously reported in order to acquaint physicians with both its effectiveness for dissolution of common bile duct calculi and the limitations of its use. Ten patients with 13 biliary calculi underwent percutaneous stone dissolution treatment with the experimental cholesterol solvent, MTBE. Three stones completely dissolved within 30 minutes, seven were reduced in size, and three were visibly unaffected. All stones not completely dissolved were easily extracted by means of a stone basket except for one in a patient taken to surgery. Although MTBE perfusion is an effective technique for management of biliary calculi, practitioners should be aware that its use is quite time consuming and its odor difficult to control.  相似文献   
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