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51.
Effects of different tuberculin skin-testing regimens on gamma interferon and antibody responses in cattle experimentally infected with Mycobacterium bovis 下载免费PDF全文
Palmer MV Waters WR Thacker TC Greenwald R Esfandiari J Lyashchenko KP 《Clinical and Vaccine Immunology : CVI》2006,13(3):387-394
Although tuberculin skin testing has been a hallmark of bovine tuberculosis eradication campaigns, it lacks sensitivity, can be confounded by exposure to nontuberculous mycobacteria, and cannot be repeated for 60 days due to desensitization. To overcome these difficulties, an effective whole-blood cellular immunoassay for bovine gamma interferon (IFN-gamma) has been developed. The IFN-gamma test is commonly used in conjunction with tuberculin skin testing as a confirmatory test following a positive response to the caudal fold test (CFT). The present study was conducted to determine the effect of different tuberculin skin-testing regimens on IFN-gamma and antibody production by using calves that were experimentally infected with Mycobacterium bovis. Holstein calves were CFT tested 60 days after inoculation and the comparative cervical test (CCT) was conducted 7 (7-day CCT) or 55 (55-day CCT) days after the CFT. In both the 7-day CCT and 55-day CCT groups, IFN-gamma responses increased 3 days after the CFT; this was immediately followed by a decrease to pre-skin test levels 7 days after the CFT. In both groups, the application of the CCT at 7 or 55 days after the CFT resulted in no significant increase in IFN-gamma production. The administration of the CFT and the CCT to M. bovis-inoculated cattle boosted antibody responses to M. bovis PPD, rMPB83, ESAT-6, and the fusion protein Acr1-MPB83. The boosting effect was more pronounced in the 55-day CCT group. Increases in either IFN-gamma or antibody production were not seen in noninoculated cattle. Measurement of both IFN-gamma and antibody responses after skin testing may be useful in identifying M. bovis-infected cattle; however, the timing of collection of such samples may influence interpretation. 相似文献
52.
Menopausal hormone therapy (HT) in patients with breast cancer 总被引:2,自引:0,他引:2
OBJECTIVES: To assess the effect of menopausal hormone therapy (HT) on reoccurrence, cancer-related mortality, and overall mortality after a diagnosis of breast cancer. METHODS: We performed a quantitative review of all studies reporting experience with menopausal HT for symptomatic use after a diagnosis of breast cancer. Rates of reoccurrence, cancer-related mortality, and overall mortality were calculated in this entire group. A subgroup analysis was performed in studies using a control population to assess the odds ratio of cancer reoccurrence and mortality in hormone users versus non-users. RESULTS: Fifteen studies encompassing 1416 breast cancer survivors using HT were identified. Seven studies included a control group comprised of 1998 patients. Among the 1416 HT users, reoccurrence was noted in 10.0% (95% CI: 8.4-11.6%). Cancer-related mortality occurred at a rate of 2.6% (95% CI: 1.8-3.7%), while overall mortality was 4.5% (95% CI: 3.4-5.8%). Compared to non-users, patients using HT had a decreased chance of reoccurrence and cancer-related mortality with combined odds ratio of 0.5 (95% CI: 0.2-0.7) and 0.3 (95% CI: 0.0-0.6), respectively. CONCLUSIONS: In our review, menopausal HT use in breast cancer survivors was not associated with increased cancer reoccurrence, cancer-related mortality or total mortality. Despite conflicting opinions on this issue, it is important for primary care physicians to feel comfortable medically managing the increasing number of breast cancer survivors. In the subset of women with severe menopausal symptoms, HT options should be reviewed if non-hormonal methods are ineffective. Future trials should focus on better ways to identify breast cancer survivors who may safely benefit from HT versus those who have a substantial risk of reoccurrence with HT use. 相似文献
53.
Symptomatic peripheral arterial disease: the value of a validated questionnaire and a clinical decision rule 下载免费PDF全文
Bianca LW Bendermacher Joep AW Teijink Edith M Willigendael Marie-Louise Bartelink Harry R Büller Ron JG Peters Jelis Boiten Machteld Langenberg Martin H Prins 《The British journal of general practice》2006,56(533):932-937
BACKGROUND: If a validated questionnaire, when applied to patients reporting with symptoms of intermittent claudication, could adequately discriminate between those with and without peripheral arterial disease, GPs could avoid the diagnostic measurement of the ankle brachial index. AIM: To investigate the Edinburgh Claudication Questionnaire (ECQ) in general practice and to develop a clinical decision rule based on risk factors to enable GPs to easily assess the likelihood of peripheral arterial disease. DESIGN OF STUDY: An observational study. SETTING: General practice in The Netherlands. METHOD: This observational study included patients of > or =55 years visiting their GP for symptoms suggestive of intermittent claudication or with one risk factor. The ECQ and the ankle brachial index were performed. The prevalence of peripheral arterial disease, defined as an ankle brachial index <0.9, was related to risk factors using logistic regression analyses, on which a clinical decision rule was developed and related to the presence of peripheral arterial disease. RESULTS: Of the 4790 included patients visiting their GP with symptoms suggestive of intermittent claudication, 4527 were eligible for analyses. The prevalence of peripheral arterial disease in this group was 48.3%. The sensitivity of the ECQ was only 56.2%. The prevalence of peripheral arterial disease in a clinical decision rule that included age, male sex, smoking, hypertension, hypercholesterolemia, and a positive ECQ, increased from 14% in the lowest to 76% in the highest category. CONCLUSION: This study indicates that the ECQ alone has an inadequate diagnostic value in detecting patients with peripheral arterial disease. The ankle brachial index should be performed to diagnose peripheral arterial disease in patients with complaints suggestive of intermittent claudication, although our clinical decision rule could help to differentiate between extremely high and lower prevalence of peripheral arterial disease. 相似文献
54.
Unique performance characteristics of Novafil 总被引:1,自引:0,他引:1
G T Rodeheaver D C Borzelleca J G Thacker R F Edlich 《Surgery, gynecology & obstetrics》1987,164(3):230-236
Polybutester is a unique copolymer that can be extruded as a flexible monofilament nonabsorbable suture. The mechanical performance of this new suture material was compared with that of polypropylene and nylon. The results indicate that polybutester sutures are as strong, have the same degree of total elongation at break and knot as the other monofilament sutures. In contrast with polypropylene and nylon sutures, the polybutester sutures have a perceptible stretch, are more elastic and flexible, and exhibit less creep. Polybutester sutures appear to be an acceptable alternative to polypropylene and nylon sutures and their unique mechanical properties may even prove to be superior in vivo. 相似文献
55.
56.
The soil receives enormous quantities of pesticides and PCBs as a waste product each year due to their wide application. The degradation and eventual fate of these chemicals in the soil largely determine ultimate environmental impact. A survey of an abandoned landfill site has been conducted in a fast developing industrial city Nagpur (India) to assess the degree of environmental contamination with PCBs. The purpose was to determine if any of the mixture of PCBs, Aroclor 1254 and Aroclor 1260 are retained in the compost amended soil of the site despite atmospheric losses possible due the peak summer (100-117 degrees F) in the city. The accuracy and precision for Aroclor 1254 and Aroclor 1260 determinations in the soil samples have been calculated as 76.5 and +/- 0.92 and 83.3 and +/- 1.13 respectively. The samples analysis showed the presence of Aroclor 1254 and Aroclor 1254 and Aroclor 1260 up to the levels of 0.55 and 0.80 mg/g respectively. The maximum total PCBs on dry weight basis are found as 1.2 mg/g. 相似文献
57.
Szarmach RR Livingston J Rodeheaver GT Thacker JG Edlich RF 《Journal of long-term effects of medical implants》2002,12(4):211-229
This report describes an innovative suture and needle clinical evaluation program jointly designed by hospital representatives of Consorta, Inc., a healthcare resource management and group purchasing organization, and United States Surgical/Davis & Geck Sutures (USS/D&G), manufacturer of surgical biomaterials. Nineteen Consorta shareholder hospitals enrolled 699 surgeons to participate in Phase I of this nonexperimental observational study of the clinical performance of surgical needles and sutures. Performance characteristics of the sutures and needles produced by USS/D&G, which were evaluated in 3407 surgical procedures, included packaging and ease of opening, needle strength and sharpness, tissue drag, knot security, tensile strength, and clinically acceptable and unacceptable determinations. In these 30-day studies, the surgeons concluded that the needles and sutures were clinically acceptable in 98.1% of the evaluations. The general, cardiothoracic, and orthopedic surgeons, who performed 73.8% of the product evaluations, reported that the suture and needle products were clinically acceptable in 97.2% of the evaluations. More than half (50.1%) of the evaluations involved the POLYSORB* braided synthetic sutures,which received a clinically acceptable rating in 98.4% of the evaluation. The next most frequently used sutures were the SOFSILK*, followed by the monofilament nylon suture. SOFSILK* was found to be clinically acceptable in 98.7% of the evaluations, whereas the monofilament nylon was noted to be clinically acceptable in 96.3% of the evaluations. Surgical needles made by USS/D&G had a 97.9% clinical acceptability rating. 相似文献
58.
Imray CH Mead MK Thacker AJ Dimitri WR 《British journal of anaesthesia》2002,88(2):303-4; author reply 303-4
59.
Joseph L Demer Maria Carolina Ortube Elizabeth C Engle Neepa Thacker 《Journal of AAPOS》2006,10(2):135-142
INTRODUCTION: Although the ocular motility examination has been used traditionally in the diagnosis of strabismus that is a result of cranial nerve (CN) abnormalities, magnetic resonance imaging (MRI) now permits the direct imaging of lesions in CN palsies. METHODS: Prospectively, nerves to extraocular muscles (EOMs) were imaged with T1 weighting in orbits of 83 orthotropic volunteers and 96 strabismic patients in quasicoronal planes using surface coils. Intraorbital resolution was 234-312 microns within 1.5- to 2.0-mm thick planes. CNs were imaged at the brainstem using head coils and T2 weighting, yielding 195 micron resolution in planes 1.0-mm thick in 6 normal volunteers and 22 patients who had oculomotor (CN3), trochlear (CN4), or abducens (CN6) palsies and Duane syndrome. RESULTS: Oculomotor (CN3) and abducens (CN6) but not trochlear (CN4) nerves were demonstrable in the orbit and skull base in all normal subjects. Patients with congenital CN3 palsies had hypoplastic CN3s both in orbit and skull base, with hypoplasia of involved EOMs. Patients with chronic CN6 and CN4 palsies exhibited atrophy of involved EOMs. Patients with Duane syndrome exhibited absence or hypoplasia of CN6 in both orbit and brainstem regions, often with mild hypoplasia and apparent misdirection of CN3 to the lateral rectus muscle. Unlike CN6 palsy, patients with Duane syndrome exhibited no EOM hypoplasia. Patients with congenital fibrosis exhibited severe hypoplasia of CN3, moderate hypoplasia of CN6, and EOM hypoplasia, particularly severe for the superior rectus and levator muscles. CONCLUSION: High-resolution MRI can directly demonstrate pathology of CN3 and CN6 and affected EOM atrophy in strabismus caused by CN palsies. Direct imaging of CNs and EOMs by MRI is feasible and useful in differential diagnosis of complex strabismus. 相似文献
60.