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41.
Interobserver variability in neonatal cranial ultrasonography   总被引:1,自引:0,他引:1  
The reliability of cranial ultrasound diagnosis in the premature neonate was examined using data from an ongoing multicentre study of the epidemiology and long-term consequences of neonatal brain haemorrhage. First week ultrasound films (obtained at 4 hours, 24 hours and 7 days) from 60 study subjects were randomly selected for independent review by two groups of experienced interpreters, and results were recorded separately for observations (i.e. presence or absence of an abnormal echodense area on a film) and interpretations (i.e. presence or absence of haemorrhage or ventricular dilatation) in each hemisphere. Because of deaths in the first week of life, the total number of films examined was 138. Concordance on the presence or absence of an abnormal echodensity was examined for each individual film for three areas of interest: the germinal matrix, the ventricles and the parenchyma. Concordance on the presence or absence of haemorrhage or ventricular dilatation was examined only for the seventh-day film, or the final film prior to death. Finally, concordance was analysed with the diagnostic interpretations grouped into categories thought to differ prognostically for long-term outcome. In general, concordance was poorest for germinal matrix lesions and best for parenchymal lesions. Concordance was lower for observations made on each individual film than it was for interpretation of the final film in each case. Fifty-five of 60 cases (92%) were assigned to the same major prognostic category by both readers. Ultrasound review conferences were held periodically and there was evidence that concordance in ultrasound reading and interpretation improved during the course of the study.  相似文献   
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A 91-year-old man developed a mass in the right medial canthal and lacrimal sac region, which was found histopathologically to be a poorly differentiated neoplasm. The results of a complete systemic evaluation, including urologic consultation, rectal examination, bone scan, and determination of serum acid phosphatase level, were normal. In spite of the negative evaluation for prostatic carcinoma, immunohistochemical studies using immunoperoxidase stains for prostatic-specific antigen demonstrated that the lacrimal sac tumor was metastatic carcinoma from an occult primary neoplasm in the prostate gland. The presence of tumor in the prostate gland was then confirmed by a needle biopsy. Modern immunohistochemical techniques are particularly valuable in the diagnosis of selected ophthalmic tumors in which the diagnosis cannot be determined by routine diagnostic techniques.  相似文献   
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OBJECTIVE: The objective of this retrospective cohort study was to determine whether coronary artery bypass graft (CABG) surgery is effective and cost-effective relative to medical management of coronary artery disease (CAD) in the elderly. SUMMARY BACKGROUND DATA: The aging of the U.S population and the improvements in surgical techniques have resulted in increasing numbers of elderly patients who undergo this surgery. The three randomized, controlled trials (RCTs) that established the efficacy of CABG surgery completed patient enrollment from 19 to 24 years ago excluded patients older than 65 years. Although information regarding outcomes of CABG in this population is mainly available in case series, a major lacuna exists with respect to information on quality of life and cost effectiveness of surgery as compared with medical management. METHODS: The authors retrospectively formed surgical and medically managed cohorts of octogenarians with significant multivessel CAD. More than 600 medical records of patients older than 80 years who underwent angiography at our institution were reviewed to identify 48 patients who were considered reasonable surgical candidates but had not undergone surgery. This cohort was compared with 176 patients who underwent surgery. RESULTS: The cost per quality-adjusted life year saved was $10,424. At 3 years, survival in the surgical group was 80% as compared with 64% in the entire medical cohort and 50% in a smaller subset of the medical cohort. Quality of life in patients who underwent surgery was measurably better than that of the medical cohort with utility index scores, as measured by the EuroQoL, (a seven-item quality of life questionnaire) of 0.84, 0.61, and 0.74, respectively. CONCLUSIONS: Performing CABG surgery in octogenarians is highly cost-effective. The quality of life of the elderly who elect to undergo CABG surgery is greater than that of their cohorts and equal to that of an average 55-year-old person in the general population.  相似文献   
46.
Blood platelet uptake of serotonin in episodic aggression   总被引:2,自引:0,他引:2  
Blood platelet uptake of 3H-serotonin (5HT uptake), a potential marker of serotonergic function, was determined in male outpatients with episodic aggression (n = 15) and in age- and sex-matched nonaggressive controls (n = 15). Correlations with rating scales of "impulsivity" (Barratt Impulsivity Scale, 10th revision) and "anger" (Spielberger Anger Expression Scale) were performed. Mean 5HT uptake was 18% lower in patients with episodic aggression. A significant negative correlation between % difference in platelet 5HT uptake and impulsivity score was observed, but the correlation between 5HT uptake and anger was not significant. These results support the hypothesis of disturbed serotonergic function in aggression and suggest that the primary relationship is in the "control" of aggression. The blood platelet may be useful in identifying impulsive subtypes.  相似文献   
47.
M. Elaine Rose 《Immunology》1961,4(4):346-353
Antibodies to Eimeria stiedae were measured in rabbit serum by complement fixation. The titre rose to a maximum at about the 22nd day after infection, remained at this level for about 20 days and then declined. Antibodies were still detectable up to 160 days after infection.

Evidence of past or present slight E. stiedae infection was found in clinically normal rabbits whose sera fixed complement with E. stiedae antigens.

Challenge of rabbits which had recovered from a near-fatal infection had no effect upon the complement fixation titres of their sera.

The serum of a rabbit which had been injected with alum-precipitated antigen fixed complement with E. stiedae antigens. However, the animal was still susceptible to a superimposed oral infection which had the effect of further increasing the serum titre.

  相似文献   
48.
Solid-organ transplant recipients are at risk for development of lymphoproliferative diseases. The purpose of this study was to examine the distribution of Epstein-Barr virus (EBV) load in the peripheral blood of pediatric transplant recipients who had become chronic viral load carriers (>8 copies/10(5) lymphocytes for >2 months). A total of 19 patients with viral loads ranging from 20 to 5,000 viral genome copies/10(5) lymphocytes were studied. Ten patients had no previous diagnosis of posttransplant lymphoproliferative disease (PT-LPD), while nine had recovered from a diagnosed case of PT-LPD. No portion of the peripheral blood viral load was detected in the cell-free plasma fraction. Viral DNA was found in a population of cells characterized as CD19(hi) and immunoglobulin D negative, a phenotype that is consistent with the virus being carried exclusively in the memory B-cell compartment of the peripheral blood. There was no difference in the compartmentalization based upon either the level of the viral load or the past diagnosis of an episode of PT-LPD. These results have implications for the design of tests to detect EBV infection and for the interpretation and use of positive EBV PCR assays in the management of transplant recipients.  相似文献   
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50.
T-Cell Regulation in Autoimmune Thyroiditis   总被引:12,自引:0,他引:12  
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