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61.
62.
To determine the duration of immunity to Plasmodium vivax following immunization, six Saimiri sciureus boliviensis monkeys were vaccinated with irradiated sporozoites of P. vivax and challenged multiple times with sporozoites. Over a period of almost four years, complete protection from repeated challenge with infective sporozoites was demonstrated in one monkey; protection in two monkeys was obtained on eight of nine occasions, in one monkey on seven of nine occasions, in one monkey on six or nine occasions, and in one monkey on four of eight occasions. Five of six monkeys were protected against infection during the last six challenges. Inoculation with blood-stage parasites at the end of the trial indicated that all animals were susceptible to infection. These results suggest that protection against sporozoite challenge may be strongly reinforced by subsequent exposure to viable sporozoites.  相似文献   
63.
The discordance between extremely high seroprevalence of Taenia solium antibodies in disease-endemic populations, relatively few symptomatic cases of neurocysticercosis, and high background levels of putatively inactive brain lesions (mainly calcifications) in seronegative controls have confused researchers, clinicians, and epidemiologists in the last decade. We reviewed longitudinal serologic data from general population serosurveys in 3 different disease-endemic areas of Peru and Colombia and found that approximately 40% of seropositive people were seronegative when resampled after 1 year (3 surveys) or after 3 years (1 survey). Transient antibodies may have significant implications for the epidemiology of and immunity to this disease.  相似文献   
64.
OBJECTIVE—To determine whether the β blocker esmolol reduces coronary artery wall stress more than the short acting dihydropyridine calcium antagonist nicardipine.
DESIGN—Randomised double blind placebo controlled trial.
SETTING—Tertiary cardiology centre.
PATIENTS—Patients with coronary artery disease.
INTERVENTIONS—20 patients were randomised double blind to an infusion of nicardipine (n = 10) or esmolol (n = 10) titrated to reduce systolic blood pressure by 20 mm Hg.
MAIN OUTCOME MEASURES—Peak systolic wall circumferential stress.
RESULTS—Esmolol reduced peak coronary stress by a mean of 0.17 × 106 dyn/cm2 (95% confidence interval (CI) 0.14 to 0.21 × 106 dyn/cm2) compared with a reduction of 0.07 × 106 dyn/cm2 (95% CI 0.05 to 0.10 × 106 dyn/cm2) after nicardipine. Peak systolic radius was reduced by 0.04 mm (95% CI 0.03 to 0.06 mm) after esmolol compared with an increase of 0.08 mm (95% CI 0.05 to 0.10 mm) after nicardipine. Heart rate increased by 11.5 beats/min (95% CI 6.9 to 16.2 beats/min) after nicardipine and decreased by 5.3 beats/min (95% CI 1.9 to 8.6 beats/min) after esmolol.
CONCLUSIONS—Intravenous esmolol is more effective than nicardipine at reducing circumferential coronary artery wall stress.


Keywords: β blockers; calcium channel antagonists; mechanics; coronary disease  相似文献   
65.
To investigate the long-term changes in left ventricular structure and function after myocardial infarction, 51 patients with a first myocardial infarction (17 anterior, 23 inferior, and 11 non-Q wave) were studied by two-dimensional echocardiography at the time of entry into the hospital, at 3 months, and 1 year after infarction. The left ventricular endocardial surface was reconstructed from these echocardiograms, and the endocardial surface area (ESA) index (in cm2/m2) and area of abnormal wall motion (AWM in cm2) were quantitated. Despite different trends in the ESA index between entry and 3-month values in those with and without early infarct expansion, a decrease in the ESA index from 3 months to 1 year was noted in anterior and non-Q wave infarctions (anterior with early expansion: 96.3 +/- 8.6 to 81.5 +/- 4.2 cm2/m2, p less than 0.05; anterior without early expansion: 59.7 +/- 2.0 to 54.7 +/- 2.0 cm2/m2, p less than 0.01; non-Q wave: 64.1 +/- 3.5 to 57.9 +/- 4.4 cm2/m2, p less than 0.01). The mean decline in ESA from 3 months to 1 year of 8.9 +/- 2.5 cm2 was independent of initial infarct size. Regional function, as represented by the area of AWM, was also improved but the timing of the improvement was related to the location and size of the infarction.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
66.
Tuberculous valvular endocarditis is exceptionally rare. It is usually manifest in the context of miliary tuberculosis, and in all but one case the diagnoses have been made at necropsy. Because of its rarity there is still uncertainty as to whether true tuberculous endocarditis exists as a clinical entity. This paper describes a case of miliary tuberculosis with aortic valvulitis that resolved on antituberculous therapy.  相似文献   
67.
68.
ObjectiveThe American Association for Geriatric Psychiatry (AAGP) Scholars Program was developed to recruit trainees into geriatric psychiatry fellowships and is considered a pipeline for fellowship recruitment. Nonetheless, the number of trainees entering geriatric psychiatry fellowship is declining, making it important to identify modifiable factors that may influence trainees’ decisions to pursue fellowship. We analyzed survey data from Scholars Program participants to identify demographic characteristics, attitudes toward program components, and behaviors after the program that were independently associated with the decision to pursue fellowship.MethodsWeb-based surveys were distributed to all 289 former Scholars participants (2010–2018), whether or not they had completed geriatric psychiatry fellowships. We conducted a hierarchical binary logistic regression analysis to examine demographics, program components, and behaviors after the program associated with deciding to pursue geriatric psychiatry fellowship.ResultsSixty-one percent of Scholars decided to pursue geriatric psychiatry fellowship. Attending more than one AAGP annual meeting (relative variance explained [RVE] = 34.2%), maintaining membership in the AAGP (RVE = 28.2%), and rating the Scholars Program as important for meeting potential collaborators (RVE = 26.6%) explained the vast majority of variance in the decision to pursue geriatric psychiatry fellowship.ConclusionNearly two-thirds of Scholars Program participants decided to pursue geriatric psychiatry fellowship, suggesting the existing program is an effective fellowship recruitment pipeline. Moreover, greater involvement in the AAGP longitudinally may positively influence Scholars to pursue fellowship. Creative approaches that encourage Scholars to develop collaborations, maintain AAGP membership, and regularly attend AAGP annual meetings may help attract more trainees into geriatric psychiatry.  相似文献   
69.
The U.S. Deaf community—more than half a million Americans who communicate using American Sign Language (ASL)—experiences higher rates of trauma exposure and substance use disorder (SUD) than the general population. Yet there are no evidence-based treatments for any behavioural health condition that have been evaluated for use with Deaf people. The driving aim of our work, therefore, has been to develop and formally evaluate a Deaf-accessible trauma/SUD counselling approach. Here we describe our initial intervention development work and a single-arm pilot that evaluated the feasibility, acceptability, and preliminary clinical efficacy of Signs of Safety—a Deaf-accessible toolkit to be used with an existing, widely adopted protocol for trauma and addiction (Seeking Safety). Preliminary efficacy results indicated clinically significant reductions in PTSD symptoms and frequency of alcohol use for the Seeking Safety/Signs of Safety model. Frequency of drug use did not change significantly—likely attributable to the mid-study legalization of recreational marijuana in our state. Next steps include the redesign and refilming of Signs of Safety based on pilot participant feedback, again using a Deaf-engaged development and production process. This new toolkit will be tested via a pilot randomized controlled trial designed based on present methodological lessons learned.  相似文献   
70.

Background

Laparoscopic hernia repair is used widely for the repair of incisional hernias. Few case studies have focussed on purely ‘incisional’ hernias. This multicentre series represents a collaborative effort and employed statistical analyses to provide insight into the factors predisposing to recurrence of incisional hernia after laparoscopic repair. A specific hypothesis (ie, laterality of hernias as well as proximity to the xyphoid process and pubic symphysis predisposes to recurrence) was also tested.

Methods

This was a retrospective study of all laparoscopic incisional hernias undertaken in six centres from 1 January 2004 to 31 December 2010. It comprised a comprehensive review of case notes and a follow-up using a structured telephone questionnaire. Patient demographics, previous medical/surgical history, surgical procedure, postoperative recovery, and perceived effect on quality of life were recorded. Repairs undertaken for primary ventral hernias were excluded. A logistic regression analysis was then fitted with recurrence as the primary outcome.

Results

A total of 186 cases (91 females) were identified. Median follow-up was 42 months. Telephone interviews were answered by 115/186 (62%) of subjects. Logistic regression analyses suggested that only female sex (odds ratio (OR) 3.53; 95% confidence interval (CI) 1.39–8.97) and diabetes mellitus (3.54; 1–12.56) significantly increased the risk of recurrence. Position of the defect had no statistical effect.

Conclusions

These data suggest an increased risk of recurrence after laparoscopic incisional hernia repair in females and subjects with diabetes mellitus. These data will help inform surgeons and patients when considering laparoscopic management of incisional hernias. We recommend a centrally hosted, prospectively maintained national/international database to carry out additional research.  相似文献   
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