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81.
Results of intradermal skin test responses to the same panel of 53 allergens were compared in 118 dogs with atopic disease presented at two geographical centres, Edinburgh (87 cases) and London (31 cases). The allergens most commonly positive at both centres were human dander and Dermatophagoides farinae, but positive tests to all of the allergens used occurred in at least one case. The mean number of allergens to which positive tests resulted in atopic dogs was 5.126 (Edinburgh) and 5.129 (London). The majority of animals were sensitive to allergens from more than one group. A significantly higher number of positive reactors to house dust allergen was observed at London than at Edinburgh (P < 0.05), while a significantly higher number of positive reactions to grass pollens was detected at Edinburgh than in London (P < 0.05). Sensitivity to Dermatophagoides pteronyssinus, in the absence of sensitivity to D. farinae, was uncommon and therefore both of these mite allergens should be incorporated in intradermal skin testing panels in Great Britain.  相似文献   
82.
The efficacy of ultrasound compared with ascending venography for the detection of deep venous thrombosis immediately after total knee arthroplasty was assessed after a 2-year interval. One hundred thirty-seven patients were eligible for the study; however, 31 patients received only one of the screening methods and a color Doppler examination was inconclusive in six patients. Therefore, 100 patients had a Doppler examination and a venogram. Overall, the sensitivity of ultrasound was 85%, the specificity 97%, the positive predictive value 85%, the negative predictive value 97%, and the accuracy 95%. The sensitivity in the calf was 83%, in the popliteal vein 86%, and in the femoral vein 100%. Two years ago, the initial assessment of ultrasound for the detection of deep venous thrombosis after surgery in patients who had total joint arthroplasty revealed a 75% sensitivity, 99% specificity, 91% positive predictive value, 97% negative predictive value, and 97% accuracy. The sensitivity in the calf was 83%; the sensitivity in the popliteal vein was 40%; and the sensitivity in the femoral vein was 50%. After 2 years of using this screening test with one technician and one radiologist, an improvement with this noninvasive technique was shown. However, it was found that Doppler imaging is not as sensitive as venography for detecting calf thrombi. Any imaging technique should be validated by each institution to determine the validity of the instrument and the learning curve of the technician administering the examination.  相似文献   
83.
This article determines whether it is possible to decrease the number of review appointments following wisdom teeth removal without detriment to the patient. A prospective single-centre study was undertaken in a general hospital with 130 consecutive patients undergoing the removal of impacted wisdom teeth.  相似文献   
84.
An 11-month-old girl had massive rectal bleeding. A midabdominal mass was palpated. Ultrasound scan showed a large cystic mass with diffusely echogenic contents; Tc-99M radionuclide scan confirmed a duplication. Exploratory surgery and pathology examination showed a gastric duplication with formation of a fistula into the transverse colon with a colonic ulcer and hemorrhage. This combination of findings is presented as a rare cause of lower gastrointestinal hemorrhage in infancy.  相似文献   
85.
To compare multiple and singleton pregnancies in the treatment of threatened preterm delivery with prolonged intravenous ritodrine, 32 women with multiple pregnancy (26 twins, 6 triplets, 70 fetuses, 30.3 +/- 3.5 weeks) and 51 women with singleton pregnancy (31.3 +/- 2.6 weeks) admitted for threatened preterm delivery without rupture of the membranes were the subjects of a retrospective study of obstetric data, perinatal outcome and maternal adverse effects. Significance was assessed by chi 2 test and Student's t test. Multiple pregnancies were associated with a marked increase in the duration of tocolysis (17.2 +/- 17.3 vs. 7.6 +/- 8.1 days, P < 0.01), incidence of delivery before 37 weeks (87.5 vs. 35.3%, P < 0.01) and incidence of maternal cardiovascular complications (34.4 vs. 4.0%, P < 0.01), including three cases of pulmonary edema. The incidences of delivery before 32 weeks (12.5 vs. 7.8%) and of neonatal death (2.9 vs. 0%) were not significantly different in the two groups. Multiple pregnancies dramatically increased the incidence of maternal adverse effects of prolonged intravenous ritodrine therapy. Neonatal benefit is questionable and was difficult to establish since it was not a randomized study.  相似文献   
86.
Most breast mass lesions are readily characterized by FNA with cytodiagnosis. Occasionally, benign but markedly proliferative lesions are diagnostically difficult to separate from well differentiated malignancies. We present information pertaining to the diagnostic significance of two cytologic findings observed in breast aspiration specimens, namely pairs of stripped bipolar nuclei and signet ring cells (SRC). We have evaluated aspirate smears from 219 cases of histologically proven benign (n = 114) and malignant (n = 105) breast lesions. Both singlets and pairs of bipolar nuclei and SRC were enumerated, and their numbers were correlated to histological diagnosis. Closely associated pairs of stripped bipolar nuclei were found in 68% of benign lesions compared with only 3.8% of carcinomas, establishing their presence as a highly specific indicator of a benign process. Large numbers of such 'benign pairs' also favoured the diagnosis of fibroadenoma. SRC were identified in 66% of histologically proven carcinomas (67% of ductal and 70% of lobular). SRC were also present in 10% of histologically benign cases. In the malignant cases, SRC were most frequently noted in a single cell distribution or within small, loosely cohesive tissue fragments. In the benign instances, SRC were most commonly noted within large fragments, and many of these cells were proved by immunohistochemical reactions to be vacuolated myoepithelial cells. We conclude that the presence of bipolar nuclei in closely associated pairs suggests benignity and aids in the subclassification of benign breast masses. In addition, the presence of SRC does not aid in the classification of tumour subtype (ductal vs lobular), and the occurrence of such cells in the proper context should prompt surgical biopsy.  相似文献   
87.
We report on a 52-year old male patient who underwent implantation of an insulin pump because he had diabetes and in whom superior vena cava syndrome developed as a long-term complication. After unsuccessful lysis therapy superficial femoral vein was implanted to form a bypass from the internal jugular vein to the right atrium. The postoperative course was uneventful from the aspects of both the bypass and the leg after explantation of the superficial femoral vein. The bypass is still patent 7 months after the operation, and the patient has no symptoms. Autogenous superficial femoral vein can be used successfully in the reconstruction of large venous vessels. It should be the graft of choice for young patients with benign diseases. We compare our result and those obtained with different substitutes described in the literature that have been used for reconstruction in superior vena cava syndrome.  相似文献   
88.
89.
This study tested the tensile dislodgment forces of two experimental post designs that are threaded 7 mm into the most coronal aspect of the root. Experimental post systems ParaPost XT-7 (XT-7), and ParaPost XT-10 (XT-10) were compared to the Flexi-Post (FP) and to the Standard ParaPost (SP). The XT-7 prototype post measured 7 mm in length, while all other post systems were 10 mm. The XT-7 and the FP are active post systems that are threaded throughout their entire length. The SP is a passive serrated post system, and the XT-10 is a combination active/passive design that has a 7 mm coronal thread with a passive serrated apical end. All systems tested were titanium alloy except the SP system, which was stainless steel. The purpose of this study was to compare an active and a passive post design to the experimental designs of the XT-7 active post and the combined active/passive design of the XT-10. This study clearly demonstrated highest retention for the active post system, least retention for the passive post, with an intermediate retentiveness for the combined design.  相似文献   
90.
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