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991.
The Naval Special Board of Flight Surgeons was established in 1956 for the evaluation of Navy, Marine Corps, and Coast Guard problem aeromedical cases. This paper examines a sample 248 of these cases for the period of 1974-83 with respect to the characteristics of those referred, their referral diagnostic category, and the recommendation of the Special Board regarding return to a flying status. Those cases with a referral diagnostic category of ENT and Ophthalmology were less likely to be returned to flight status. Older, more senior pilots, and pilots with more total flight time were less likely to be returned to unrestricted flying than were their younger, more junior, and less experienced counterparts. Otherwise, no significant difference in outcome based on age, rank, marital status, branch of service, specialty, or flight hours was detected. Overall, 61% of those evaluated by the SBFS were returned to flight status.  相似文献   
992.
The authors describe an original application of real time transducers--initially intended for intracavitary sonography--in thoraco-abdominal scanning. The stic-form probe can be easily slipped under the patient. It is then possible to realize a scan with an upward beam. In the postero-anterior scan, the patient is placed in a supine position. He is motionless. We achieve a better visualization of the liquid collections, since their accumulation is declivious. The method allows a wider sonographic window for thoraco-abdominal and diaphragmatic investigation in sonography.  相似文献   
993.
The livers of 26 adult males with acquired immune deficiency syndrome (AIDS) were reviewed. The occurrence of portal tracts with diminished lymphocytes, probably reflecting generalized exhaustion of the lymphoid system, was a characteristic morphologic change, and was found in all cases. Kupffer cell hyperplasia was also a frequent finding and probably reflected generalized infection(s). Punched-out clusters of foamy histiocytes filled with acid-fast bacilli, typical for infection with Mycobacterium avium intracellulare (MAC), were found in three patients. In addition, MAC was cultured from two livers without the foamy histiocytic changes. Chronic viral hepatitis (three cases) and deposition of polarizable materials (one case) in the liver might be related to unusual habits of patients with AIDS. In conclusion, livers from patients with AIDS disclosed several kinds of lesions reflecting underlying or associated conditions in AIDS, but these did not contribute to the cause of death in our patients.  相似文献   
994.
Pure motor hemiplegia (PMH) is, in most cases, caused by a lacunar infarction. However, pure motor monoparesis (PMM), i.e., isolated motor involvement with spasticity in one limb, has drawn little attention. We studied prospectively 5 patients with PMM and found that it was always due to a mass lesion in the contralateral superficial cerebral hemisphere. Our observation suggests that PMM should not be regarded as simply a variant of PMH.  相似文献   
995.
The purpose of the study was to compare an interview measure of quality of object relations to questionnaire and interview measures of recent interpersonal functioning with respect to the prediction of therapeutic alliance and psychotherapy outcome. The sample consisted of 64 patients who had received approximately 20 sessions of short-term individual psychotherapy within a controlled, clinical-trial investigation. Ratings of therapeutic alliance were provided independently by the patient and the therapist after each session. Outcome measures, which were provided by three sources (patient, therapist, and independent assessor), covered the areas of interpersonal functioning, psychiatric symptomatology, self-esteem, and life satisfaction. Quality of object relations, which characterizes the patient's lifelong pattern of relationships, was the best predictor. It was significantly related to patient-rated and therapist-rated therapeutic alliance and to patient improvement of both general symptomatology and specific target problems. The study also replicated previous studies that have reported significant relationships between therapeutic alliance and therapy outcome. The advantages of pretherapy predictors of therapy outcome, such as quality of object relations, are discussed.  相似文献   
996.
Hypertension has emerged as a frequent side effect in transplant recipients on effective doses of cyclosporine (CsA). To control hypertension in renal transplant patients, calcium channel blockers have been used; some of these, however, have been shown to cause significant increases in CsA levels. These findings point out that possible interactions of each calcium antagonist with CsA deserve investigation. We performed an open, placebo-controlled study in 12 stable renal transplant recipients to determine whether short-term isradipine influences CsA pharmacokinetics. All patients had mild to moderate hypertension and received triple immunosuppressive therapy with CsA, azathioprine, and prednisolone. Throughout a 4-week period of isradipine treatment, blood CsA levels (specific and nonspecific monoclonal antibodies) remained stable. The mean trough specific level was 121 +/- 14 micrograms/L following placebo, compared to 120 +/- 14 micrograms/L during isradipine. Corresponding non-specific values were 465 +/- 68 and 474 +/- 63 micrograms/L. Also, values for Cmax, AUC, and t1/2 were not significantly changed following 4 weeks of isradipine. Mean arterial pressure was significantly reduced at the end of the study. This study implies that isradipine does not influence CsA metabolism. Further studies should be carried out to determine its long-term effects on CsA pharmacokinetics and renal function in transplanted patients.  相似文献   
997.
Regulatory control of indoor Rn   总被引:2,自引:0,他引:2  
Regulation of indoor Rn is explored in the context of cost-effectiveness of regulatory action. Evaluation of cost (i.e., mitigation expenses) and benefits (i.e., savings associated with medical expenses and lost productivity related to lung cancer) at various action levels indicate that regulatory programs would be economically inefficient and unreasonable if standards were established at or below the current EPA action guide (150 Bq m-3 or less). For the approximately 95% of U.S. homes with Rn levels near or below 150 Bq m-3, government programs should continue to focus on public information and consumer protection. For the small number of homes with high Rn levels, government programs should focus on identifying high risk homes and encouraging homeowners to reduce Rn levels. Because of the potential for substantial risk reduction, such efforts would be cost-effective in these homes.  相似文献   
998.
Phosphogypsum is the by-product resulting from phosphoric acid or phosphate fertilizer production. The phosphate are used in these chemical processes contains the naturally occurring radioactive material U and all its subsequent decay products. During processing, the U generally remains in the phosphoric acid product, while the daughter, 226Ra, tends to be concentrated in the phosphogypsum. Phosphogypsum has physical properties that make it useful as a sub-base for roadways, parking lots, and similar construction. A radiological evaluation, to determine exposures to workers mixing this material with a stabilizing agent (portland cement), was performed at a South Louisiana phosphoric acid chemical plant. Measurements of the 226Ra content of the phosphogypsum showed an average of 1.1 +/- 0.3 Bq g-1 (0.7-1.7 Bq g-1). The average measured gross gamma exposure rate on the phosphogypsum pile corresponded to a dose equivalent rate of 0.368 +/- 0.006 mu Sv h-1 (0.32-0.42 mu Sv h-1). Radon daughter concentrations measured on top of the phosphogypsum pile ranged from 0.0006 to 0.001 working levels. An analysis of the airborne 226Ra concentrations showed only background levels.  相似文献   
999.
We applied a specific cytochemical reaction to characterize the glycoconjugates produced by goblet and non-goblet epithelial cells of normal human conjunctiva. For this purpose we utilized the lectins, proteins of vegetal origin, which are extremely sensitive in binding glycosidic residues. In particular, we used WGA, PNA, SBA and ConA conjugated with colloidal gold as ultrastructural marker for Transmission Electron Microscopy. This technique allowed us also to perform a quantitative analysis, by counting colloidal gold particles present on mucus granules. In this way we analyzed the content both of goblet and non-goblet epithelial cells. In the former, WGA, PNA, SBA and ConA receptors, here reported in decreasing density, were present. In the latter WGA was always positive, SBA and PNA sometimes were negative, ConA was always negative. We speculate the different contribution to mucus production by these two sources may be important in evaluating tear film stability alterations occurring in those diseases in which non-goblet epithelial cell vesicles increase.  相似文献   
1000.
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