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81.
This article describes the results of a study that used intensive direct observations of eight medical practices to assess the factors affecting the barriers and facilitators to adult immunization for influenza and pneumonia. The study aimed to describe the culture of these practices by identifying key features that facilitate or deter the immunization process. The article presents profiles of six of the eight practices describing their cultural and organizational frameworks. Six features that are critical to an understanding of the cultures of these practices, particularly as they relate to receptivity to influenza immunization for diverse practices and patient populations, are highlighted. These include policies and procedures, funding source, physician philosophy, patient receptivity to provider recommendation, and physical environment and social environment. The article also discusses strategies for applying knowledge about the culture of each practice to introduce appropriate and feasible interventions aimed at increasing immunization rates.  相似文献   
82.
In 72 drug abusers surgically treated for acute infective endocarditis, 14 patients (19%) required surgical procedures on two valves. The predominant infecting organisms were Staphylococcus aureus and Pseudomonas aeruginosa (29%). In contrast to single valve infection, congestive heart failure was the most common operative indication (86%, p less than 0.05) and was uniformly present when both left-sided valves were involved. Surgery was performed 20 +/- 13 days after initiation of antibiotic therapy, yet 7 of the 14 patients had perivalvular abscess formation. In nine patients with solely left-sided infection, aortic and mitral valve replacements were performed. In five patients with bilateral infection, partial or complete tricuspid valvectomy was performed in conjunction with one aortic and four mitral valve replacements. Tricuspid valve competence was reestablished by valve insertion or anuloplasty in two patients, and these patients experienced less perioperative heart failure than did those with tricuspid excision alone. There was no early (less than 30 day) mortality. However, long-term follow-up revealed a reoperative incidence of 21% and a 36% late mortality rate due to prosthetic valve infection with or without dehiscence at 3 to 18 months (mean 7.2 +/- 6) after the initial operation. These late infectious complications were not related to infecting organism or prosthetic material in the tricuspid anulus, but did occur in four (57%) of seven patients with intracardiac abscess. The data indicate that multiple valve infection does not preclude successful early surgical therapy, maintaining tricuspid competence may be hemodynamically preferable, and reinfection in this addict population increases late mortality.  相似文献   
83.
The molecular basis of androgen insensitivity was investigated in a family with the complete form of the syndrome. Polymerase chain reaction amplification and Southern blot analysis of genomic DNA revealed a deletion of the entire androgen receptor (AR) gene in affected individuals. The carrier status of female members of this family was examined using a HindIII restriction fragment length polymorphism associated with the AR gene. Obligate carriers were hemizygous for one of the two alleles at this locus, while heterozygosity for the polymorphic alleles, implying the presence of two copies of the AR gene, indicated noncarrier status. This conclusion was supported by gene dosage studies using comparative densitometric analysis of Southern blots hybridized simultaneously with an AR cDNA probe and a control cDNA probe from an unrelated gene. Finally, the pattern of inheritance of another X-linked DNA polymorphism allowed us to conclude that the original mutation had occurred in the germ line of the maternal great-grandfather of the index patient. Although rare, complete deletion of the AR gene is of particular importance in terms of correlation between molecular defect and phenotype, as it represents the quintessential form of complete androgen insensitivity, the null phenotype.  相似文献   
84.
85.
AIDS and Behavior - Economic vulnerability is often reported to underlie involvement in sex work among female sex workers (FSW), but may also create urgency in women’s work, limiting...  相似文献   
86.
87.
Bisphosphonates are effective treatments for osteoporosis, but some have been associated with upper gastrointestinal intolerance. This randomized, double-blind study assessed the upper gastrointestinal tolerability of risedronate in postmenopausal women who had discontinued alendronate treatment because of upper gastrointestinal adverse events. Sixty-six women who had previously discontinued treatment with alendronate 10 mg/day because of upper gastrointestinal symptoms received placebo (N=31) or risedronate 5 mg (N=35) daily for 3 months. The primary outcome was the rate of discontinuation due to upper gastrointestinal adverse events: 5/31 (16.1%) in the placebo group, and 4/35 (11.4%) in the risedronate group. Discontinuation rates were also similar in the two treatment groups among subgroups of patients with a history of gastrointestinal disorder, prior use of acid suppression drugs, and concomitant use of NSAIDs. The overall incidence of upper gastrointestinal events was comparable between the placebo (19.4%) and risedronate (20.0%) groups. Overall, risedronate 5 mg/day for 3 months was as well tolerated as placebo in patients who could not tolerate alendronate 10 mg. These results are consistent with, and complement those from previous studies showing that risedronate 5 mg has a gastrointestinal tolerability similar to that of placebo.  相似文献   
88.
The question "Has your child ever had wheezing or whistling in the chest at any time in the past?" is a simple and widely used proxy measure for the lifetime prevalence of asthma. Our aim was to test its validity in a longitudinal survey, comparing retrospective recall with prospective assessment of lifetime prevalence. A population-based cohort of 1,422 children, surveyed twice previously, was studied again at age 8-13 yrs by postal questionnaire using standardized questions from the International Study of Asthma and Allergies in Childhood (ISAAC). Of those traced (1,190) questionnaires were returned by 89%. The prevalence of current wheeze was higher than in the previous surveys (20.5% versus 12.4% and 12.5%). Reported "wheeze ever" increased significantly from survey 1 (15.6%) to survey 2 (22.4%) and survey 3 (39.2%) and was very similar to the cumulative lifetime prevalence assessed prospectively over three surveys (42.8%). The retrospective question had a good negative predictive value (97%) and a reasonable positive predictive value (65%) compared to prospective assessment. Children reporting "wheeze ever" (but not current wheeze) in surveys 1 and 2 had at survey 3 an asthma prevalence higher than never-wheezers but lower than current-wheezers. It is concluded that retrospective recall of wheeze at age 8-13 yrs is a valid proxy measure for the lifetime prevalence of wheeze.  相似文献   
89.
Right coronary arterial spasm causing Prinzmetal's variant angina   总被引:2,自引:0,他引:2  
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90.
OBJECTIVE: The aim was to evaluate the applicability of myocardial contrast echocardiography in the measurement of coronary flow reserve. METHODS: Eleven anaesthetised open chest pigs were studied, in which coronary atherosclerosis had been induced by abrasion of the left anterior descending coronary artery at one month, followed by an atherogenic diet for eight months. Coronary flow reserve was determined by electromagnetic flow measurement and contrast echocardiography before and after partial occlusion of the left anterior descending coronary artery, using papaverine as a coronary vasodilator. Coronary blood flow was reduced by tightening a clamp placed around the coronary artery. Systemic haemodynamics and myocardial wall thickness (epicardial ultrasound 5 MHz transducer) were recorded simultaneously. Echocardiograms were recorded on VHS tape and analysed by digitised videodensitometry off line for construction of the time v videointensity curve (time-intensity curves). From these curves washout time (T50), area under the curve, peak contrast intensity, and time to peak intensity were calculated. RESULTS: Following papaverine, coronary blood flow increased significantly from 47 (SD 23) ml.min-1 at baseline to 88(39) ml.min-1 (p less than 0.05). During the stenosis, flow decreased to 19(16) ml.min-1 (p less than 0.01), and increased to 38(29) ml.min-1 (p less than 0.05 v stenosis) after administration of papaverine. Correlations between coronary blood flow and indices calculated from the quantitative videodensitometric analysis were poor, varying between r = 0.03 for area at control flow to r = 0.62 for T50 during stenosis. The same was true for coronary flow reserve: r = 0.09 for peak to r = 0.75 (p less than 0.05) for time to peak without the stenosis. CONCLUSIONS: Current limitations in injection, imaging, and analysis techniques cause variability in data from time-intensity curves, which precludes accurate quantification of coronary flow (reserve) by myocardial contrast echocardiography.  相似文献   
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