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61.
Summary Since 1992, efforts have been made to combat onchocerciasis in Guatemala through mass distribution of ivermectin. The impact of the campaign is assessed by taking skin-snips from sentinel groups within selected communities. This method gives an estimate of the prevalence and intensity of infection, and thus the efficacy of the treatment. In some communities people are becoming reluctant to volunteer for skin-snipping, and so there is a need for an alternative technique that will give quantitative results. In most hyperendemic communities in Guatemala, biting blackflies are so ubiquitous that few people object to allowing 10 to 20 flies to engorge upon them. We examined data on the quantitative uptake of microfilariae by Simulium ochraceum before and after ivermectin distribution to see whether results similar to skin-snip data could be obtained. Counts of microfilariae ingested by S. ochraceum are compared to the numbers found in skin-snips from the same volunteers. In a group of 31 untreated infected persons, a skin-snip survey detected 64.5% positive, while feeding flies (vector microfilarial uptake, VmfU) detected 96.8%. Post-treatment, in a sample of 58 of whom 52 (89.7%) had a history of infection, both skin-snips and VmfU detected 54.2%. Vector blood meals contained more microfilariae than a mg of skin before treatment, but both recorded about equal numbers after treatment. When the data set was subdivided to compare samples taken at 2–3, 6–8 and 14–17 months post-treatment, the effect of ivermectin was still apparent at 6–8 months, but had virtually disappeared by 14 months post-treatment. A surprising observation was that the flies ingested fewer microfilariae from treated persons than was expected from the skin densities as estimated by skin-snip. This effect lasted for over 8 months, and could indicate that ivermectin has a greater effect on transmission than previously suspected. We conclude that VmfU could be used as an alternative to skin-snipping, and discuss the ethical implications.  相似文献   
62.
We assessed the prevalence of Parkinson's disease in Cantalejo, Spain. In 1994, we screened 1,579 persons (age > or = 40 years) using a high-sensitivity method. Cases fulfilling established clinical criteria were followed for a minimum of 3 years. Prevalences were compared with those from other door-to-door surveys. We detected 27 individuals with parkinsonism, 20 of whom had Parkinson's disease. The prevalence of Parkinson's disease increased with age and, when age-adjusted to European standards, was 9.01 per 1,000 (age 40 years and over; 10.78 in men and 5.23 in women). Of the 11 men, three were in Hoehn & Yahr grades III-IV, but six of the nine women were more severely affected. Overall, we found 18 newly diagnosed cases of parkinsonism, 13 of which were Parkinson's disease, and the majority of which were in men aged 80 years or older with a mean duration of illness of 5 years. Our prevalence figures are the highest reported, apparently because of the inclusion of several very elderly men. Parkinson's disease in Cantalejo is less severe in men than in women, particularly in those newly diagnosed. Despite the low numbers, the high prevalence and sex-related pattern are unexplained but they probably relate to the high sensitivity of the screening method.  相似文献   
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OBJECTIVE: To examine glucose tolerance in sputum-positive non-treated pulmonary tuberculosis (TB) patients as part of a general metabolic profile. Subjects. Sixty-three sputum-positive non-treated patients (male and female) attending the pulmonary clinic at Mthatha General Hospital in the Eastern Cape and 89 apparently healthy sex and age-matched volunteers. METHODS: Sixty-three untreated TB patients who came to the Mthatha General Hospital's pulmonary clinic with classic symptoms of TB, confirmed by sputum analysis, were recruited for the study. Eighty-nine apparently healthy sex and age-matched volunteers served as the control group. Anthropometric measurements were taken using an electronic scale. Standard oral glucose tolerance tests (OGTTs) were performed in both groups in the morning after an overnight fast. Anticoagulant-treated blood was analysed for glucose and insulin using Peridochrome Glucose (Boehringer Mannheim, Mannheim, Germany) and radioimmunoassay (RIA) (Diagnostic Products Corporation, Los Angeles, USA) respectively. RESULTS: There was sluggish response to glucose and insulin in the TB patient group compared with the control group. Glucose and insulin levels were significantly higher in patients at 0, 30, 60, 120, and 180 minutes. Analysis of variance gave the following p-values, viz. p = 0.0000, 0.0004, 0.0000, 0.0000 and 0.0000 for glucose, and p = 0.0317, 0.0071, 0.0000, 0.0005 and 0.0000 for insulin respectively. CONCLUSIONS: The results of this study suggest an altered glucose/insulin metabolism in TB patients. This might play an important role in the clinical course of the disease.  相似文献   
66.
OBJECTIVE: Respiratory scleroma (RS) is a progressive, chronic, granulomatous disease caused by Klebsiella rhinoscleromatis. There is only one report of RS association with HLA-DQ3. In this study, molecular association of HLA class II and RS was determined. STUDY DESIGN AND SETTING: Nine RS patients and 163 healthy controls were compared. DQA1, DQB1, and DRB1 loci were typed. RESULTS: Statistical analysis demonstrated association between DQB1*0301 and susceptibility to RS (P(c) = 0.004). Haplotype analysis showed an association of DQA1*03011-DQB1*0301 (P = 1.21E-19) and DRB1*0407-DQA1*03011-DQB1*0301 (P = 0.0002). CONCLUSIONS: Results established that DQA1*03011-DQB1*0301 haplotype is a strong risk factor for development of RS.  相似文献   
67.
Background. A major concern in evaluating dynamic cardiomyoplasty has been whether the synchronous stimulation of latissimus dorsi muscle is essential for benefit or not. We studied 10 patients to determine the efficacy of the systolic augmentation generated by the synchronous electrical stimulation of the latissimus dorsi muscle.

Methods. Left ventricular ejection fraction, end-systolic and end-diastolic volume indexes, and stroke volume index obtained during resting, peak exercise, and recovery periods (“on” values) were compared with those obtained 1 week after cessation of electrical stimulus (“off” values). Double product and estimated total body oxygen consumption at peak exercise were also calculated and compared.

Results. Higher ejection fractions (0.36 ± 0.07 versus 0.33 ± 0.06 at rest, 0.40 ± 0.07 versus 0.33 ± 0.07 peak exercise, and 0.37 ± 0.06 versus 0.31 ± 0.06 at recovery) and lower end-systolic volume indexes with relatively constant end-diastolic volume indexes were observed with the cardiomyostimulator on. Further, exercise response was better with the cardiomyostimulator on. Double product indirectly reflected better myocardial oxygen supply/demand ratio when on at peak exercise (17 ± 2.2 mm Hg × beats/min × 10−3 for on versus 19 ± 2.6 mm Hg × beats/min × 10−3 for off). Estimated total body oxygen consumption was improved at peak exercise when the cardiomyostimulator was functional (12 ± 2.7 mL · kg−1 · min−1 versus 11 ± 2.6 mL · kg−1 · min−1).

Conclusions. Current data suggest a true systolic assist during synchronous contractions of the latissimus dorsi muscle. It is thought, therefore, that synchronous electrical stimulation is essential for maximum benefit and all the beneficial effect of cardiomyoplasty certainly cannot be attributed to simple wrapping itself.  相似文献   

68.
The attainment of adequate renal protection requires strict blood pressure control and a diminution of proteinuria or microalbuminuria to values as near from normalcy as possible. It has been considered that by getting the first, the second could be attained at the same price. Recent data have confirmed that renal protection in hypertensive patients, diabetics or not, requires combination therapy that has to include an angiotensin converting enzyme inhibitor or an angiotensin receptor blocker. A calcium channel blocker can be added to this without renal compromise. A diuretic will also be needed in most cases. Proteinuria will diminish with this combination in particular if up-titration of the drug blocking the effects of angiotensin II is performed. The control of other associated risk factors is also required, in particular smoking and lipids.  相似文献   
69.
Axillary F-loop latencies (AFLL) were measured on median and ulnar nerves of 54 normal volunteers. The median and ulnar nerves were stimulated at the wrist and at the axilla 25cm distal to the sternal notch. The compound muscle action potentials were recorded from thenar and hypothenar muscles. Averaged tracings from 32 consecutive stimuli at the wrist were obtained. The averaged F-wave latencies were measured to the peak (Fwp) of the averaged F-wave. The M-wave latencies from wrist and axilla stimulation were measured to the onset of the wave (Mw and Ma, respectively). The averaged AFLL (a-AFLL) was calculated as (Fwp + Mw)-2 Ma. The average values of a-AFLL were 14.12 +/- 0.88msec for median nerve, and 13.97 +/- 0.90msec for ulnar nerve. There was no significant difference between male and female subjects, nor between the right and left sides. Seven subjects with EMG evidence of C8 or C8 to T1 radiculopathy, although manifesting normal AFLL gauged by the regular method (ie, measured to the onset of the shortest F-wave latency among eight tracings), had significantly longer "averaged AFLL" in both median and ulnar nerves of the affected side than the a-AFLL obtained from the normal side. It is concluded that the a-AFLL is a more sensitive measure than the "regular AFLL" in the assessment of proximal nerve lesion (especially C8 or C8 to T1 radiculopathy).  相似文献   
70.
Histoclinical basis for a new classification of hemorrhoidal disease   总被引:3,自引:1,他引:2  
The present classification of first, second, and third grade hemorrhoids only reflects variation in size of a normal human tissue and does not relate to "hemorrhoidal disease." Cross-sections and coronal sections of the anal canal in 32 fetuses, with ages ranging from 28 to 38 weeks of development, were studied and the following fundamental facts were found: in the lumen of the anal canals of fetuses, there are prominences of mucosa formed by conjunctive and muscular tissue, arterial and venous vessels and glands, arranged without following any particular pattern, which resemble similar formations found in the adult that protrude equally in the inside of the canal, known as hemorrhoids. The muscular tissue, smooth or striated, is grouped in bundles, and bunches of collagen fibers of homogeneous, nonfragmented, and regular aspect are found between them. Blood vessels have an ample lumen with a defined structure of collagen tissue as well as muscular tissue in its walls. Prominences of mucosa are connected to the remainder of the intestinal wall by defined conjunctive thick, nonfragmented fibers, that permit firm adherence. In healthy adults, the findings were similar but there was an evident degenerative process in the collagen fibers. In 100 surgical specimens of hemorrhoidectomies, the histologic investigation demonstrated a severe inflammatory reaction that especially affected the blood vessel wall and conjunctive tissue, which probably produced an ischemic lesion of the mucosa that could condition the onset of a vascular thrombosis, allowing displacement of the mucosa and its protrusion through the anus. The files of 815 patients suffering from hemorrhoidal disease were also studied. The main physical findings were bleeding, thrombosis of the internal hemorrhoidal plexus, prolapse of the anal cushions, or a combination of these. The authors propose to classify hemorrhoidal disease as bleeding, prolapsing, thrombotic, and mixed hemorrhoidal disease, aiming toward a rational treatment.  相似文献   
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