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991.
L C Harlan B F Polk S Cooper T P Blaszkowski J Ignatius-Smith M Stromer H Mull 《American journal of preventive medicine》1986,2(5):256-261
The effects of labeling a person as hypertensive have important implications for hypertension screening. The Hypertension Detection and Follow-up Program (HDFP) provides an opportunity to examine the effects of labeling, treatment, and study assignment on a large group of hypertensives (n = 10,070). Their answers to questions regarding perceived health and general well-being asked at baseline and again one year later were analyzed. There was no significant change in the perceived health status of persons who were unaware of their hypertension at baseline and remained untreated at one year (labeling alone). The effect of labeling plus treatment was associated with a significant decrease in perceived health. The effect of antihypertensive drug therapy on perceived health status was examined in persons who were aware of their hypertension but not on treatment at baseline, and on treatment at one year. The stepped care group (SC) had a significant improvement in their perceived health and a significant decrease in the amount of time spent worrying about their health. The referred care group (RC) had no change. Program assignment effects were studied in individuals aware of their hypertension and on treatment both at baseline and one year later. Both the SC and RC groups had a significant improvement in their perceptions of their health status. The SC group had a significant decrease in time spent worrying about their health, while the RC group showed no change. These reassuring results fail to support the suggestion that labeling persons as hypertensive is necessarily followed by negative psychological consequences.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
992.
Rabbits were exposed to submicrometer sulfuric acid mist at 1 mg/m3 for 1 hr to assess effects on alveolar region clearance of a polystyrene latex tracer aerosol. Bronchopulmonary lavage was performed at selected times after exposure for functional characterization of alveolar macrophages. In vivo, clearance was accelerated in acid exposed animals relative to sham controls. Acid exposure produced no change in the viability or numbers of macrophages recovered. Although an increase in the number of polymorphonuclear leukocytes, primary neutrophils, was observed by 1 hr in both acid and sham groups, compared to nonexposed controls, levels were normal by 12 hr in shams but continued elevated in the acid group through 24 hr. Reduced in vitro macrophage adherence was observed after acid exposure. In vivo uptake of the tracer particles by macrophages was enhanced during the first 3 hr after acid exposure and in vitro phagocytosis by polymorphonuclear leukocytes was increased through 48 hr post-exposure. The results indicate some functional alterations in free cells after in vivo exposure to H2SO4 and the production of a mild inflammatory response. This latter was associated with an acceleration of inert particle clearance from the alveolar region. 相似文献
993.
A prospective study was performed on seven male and eight female patients with normal hepatobiliary findings to investigate the effect of 20 mg nifedipine on cholecystokinin-induced gallbladder contraction. Each patient received 1 IDU (Ivy dog unit) cholecystokinin per kg body weight intravenously on two consecutive days, with additional administration of 20 mg nifedipine sublingually on the second day. Gallbladder volumes were assessed by ultrasonography over a period of 25 minutes. Cholecystokinin induced a maximal reduction in the mean initial volume of 56.8 +/- 3.6%. After nifedipine, this volume change was significantly reduced to 30.9 +/- 5.1% (p less than 0.001). Thus our data suggest for the first time that the calcium-channel-blocking agent nifedipine can have an effect on human gallbladder kinetics. 相似文献
994.
This paper critically examines the pharmacological provocation and treatment of panic disorder. An analysis of research findings on how panic attacks are induced indicates that there are psychological and non specific factors that may mediate biochemical etiological models, and these individual differences need to be investigated further. This has important implications for the psychopharmacological management of panic. A review of studies on treating panic disorder with imipramine and alprazolam emphasizes the importance of several non specific factors that include the role of self-directed in vivo exposure and changes in dysphoria and self-efficacy (subjective beliefs regarding personal competency) in predicting outcome. It is recommended that any treatment of panic-related disorders include self-directed, in vivo exposure. 相似文献
995.
996.
Mechanical properties of post and core systems 总被引:1,自引:0,他引:1
997.
998.
A A Gianelly J B Smith J R Bednar V S Dietz 《American journal of orthodontics and dentofacial orthopedics》1986,90(4):335-341
In a vertically slotted 0.022 X 0.028 inch edgewise system, the use of a two-dimensional ribbon arch--0.022 X 0.016 inch from lateral incisor to lateral incisor and 0.016 X 0.022 inch from the canine to the molars--plus an uprighting spring on the canine maintained incisor position while unilaterally protracting a molar-premolar unit by means of sliding mechanics. Five degrees of labial crown torque was placed in the incisor portion of the wire and the uprighting spring exerted a force of 200 to 250 g. The intra-arch force applied to protract the molar--premolar unit was 300 to 350 g. 相似文献
999.
W D Lovan R A Weaver R J Lentz J K Goodrum B F Withers 《Aviation, space, and environmental medicine》1986,57(4):370-375
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
1000.
Superficial bladder cancer: intravesical chemotherapy and tumour progression to muscle invasion or metastases 总被引:2,自引:0,他引:2
G Smith R A Elton G D Chisholm J E Newsam T B Hargreave 《British journal of urology》1986,58(6):659-663
Of 299 patients who presented with superficial bladder cancer (Ta, T1), 60 were treated by intravesical chemotherapy (Epodyl, methotrexate or mitomycin C). The rate of tumour progression to muscle invasion or metastases was identical for each intravesical regime. There was no evidence that mitomycin C promoted tumour progression. Carcinoma in situ in non-tumour-bearing urothelium was the most significant predictive factor for progression to muscle invasion or metastases. 相似文献