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Ten patients with juvenile rheumatoid arthritis and age- and sex-matched healthy controls were investigated in pairs. The patients were found to have both normal proportions and normal absolute numbers of T lymphocytes, B lymphocytes, and the Fc-receptor-bearing lymphoid cells in peripheral blood. No abnormality of mitogen-induced lymphocyte transformation was observed. Lymphocyte-mediated cytotoxicity induced by phytohemagglutinin (PHA) or anti-target cell antibodies was also found to be normal. As in an earlier study, impaired delayed hyper-sensitivity by skin testing was observed in the patient group, thus indicating a dissociation between in vivo and in vitro parameters of lympboid cell function.  相似文献   
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The cytotoxicity of human peripheral blood lymphocytes against chicken erythrocytes sensitized by rabbit antibodies was inhibited by human immunoglobulin and immunoglobulin fragments. Myeloma proteins isolated in dimeric state or aggregated by heat treatment inhibited better than the corresponding monomeric proteins. Strong inhibition was observed with IgG1 and IgG3, and with IgG2 after aggregation, while IgG4 inhibited very little. No inhibition was found with IgM, IgA. IgD and IgE. The F(ab')2. and Fab fragments of IgG inhibited poorly or not at all. While- considerable inhibition was observed with the Fc fragment, the pFc' fragment, which roughly corresponds to the C-terminal half of the Fc portion, showed little inhibitory capacity. A fragment isolated from IgG3, containing an extension of the N-terminal part of Fc (the Fch fragment), was an even better inhibitor than tin Fc fragment. The inhibitory capacity of the Fch and Fc fragments was greatly diminished following partial reduction and alkylation On the basis of the inhibitory pattern of IgG fragments, it is suggested that the region on the immunoglobulin molecule involved in binding to the Fc receptor of the effector lymphocytic cell may be located within the CH2 domain.  相似文献   
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Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent.  相似文献   
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IntroductionReoperative parathyroidectomy for persistent and recurrent primary hyperparathyroidism is dependent on radiology. This study aimed to compare outcomes in reoperative parathyroidectomy at a single centre using a combination of traditional and newer imaging studies.Materials and methodsRetrospective case note review of all reoperative parathyroidectomies for persistent and recurrent primary hyperparathyroidism over five years (June 2014 to June 2019; group A). Imaging modalities used and their positive predictive value, complications and cure rates were compared with a published dataset spanning the preceding nine years (group B).ResultsFrom over 2000 parathyroidectomies, 147 were reoperations (101 in group A and 46 in group B). Age and sex ratios were similar (56 vs 62 years; 77% vs 72% female). Ultrasound use remains high and shows better positive predictive value (76% vs 57 %). 99mTc-sestamibi use has declined (79% vs 91%) but the positive predictive value has improved (74% vs 53%). 4DCT use has almost doubled (61% vs 37%) with better positive predictive value (88% vs 75%). 18F-fluorocholine positron emission tomography-computed tomography and ultrasound-guided fine-needle aspiration for parathyroid hormone are novel modalities only available for group A. Both carried a positive predictive value of 100%. Venous sampling with or without angiography use has decreased (35% vs 39%) but maintains a high positive predictive value (86% vs 91%). Cure rates were similar (96% vs 100%). Group A had 5% permanent hypoparathyroidism, 1% permanent vocal cord palsy and 1% haematoma requiring reoperation. No complications for group B.ConclusionOptimal imaging is key to good cure rates in reoperative parathyroidectomy. High-quality, non-interventional imaging techniques have produced a shift in the preoperative algorithm without compromising outcomes.  相似文献   
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We aimed to compare ovarian (O), uterine (U) and spiral (S) artery (A) resistance of patients diagnosed as fertile, unexplained infertility (UI) and tubal factor infertility (TFI) in the peri-implantation period and independent from the impact of the treatment. UI (n?=?70), TFI (n?=?75) and fertile (n?=?72) patients’ ovarian, uterine and spiral artery pulsatility index (PI), resistance index (RI) and the endometrial thickness, serum estradiol and progesterone levels were compared. The specificity and sensitivity values were calculated according to determined cutoff values. Both TFI and control groups’ UA PI values were significantly lower than the UI group’s PI values. The highest UA RI values were found in UI group and the lowest values were in the control group. UI and TFI groups’ OA PI/RI values were significantly higher than the control group. Both the control and TFI groups’ SA PI/RI values were significantly lower than UI group’s PI/RI values. UI patients’ uterine and spiral arteries PI values >1.86 and >0.85, RI values >0.80 and >0.53 can be used as a valuable test showing reduced uterine perfusion. Ovarian artery PI values >0.96 and RI values >0.58 can be used as tests showing decreased ovarian perfusion in patients with TFI. In these patients, embryo cryopreservation can be considered.  相似文献   
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INTRODUCTION: Despite of the tissue engineering efforts to substitute the bladder, almost all the urinary diversion techniques still need gastrointestinal segments that have many well documented complications including the life threatening ones such as renal insufficiency and electrolytes imbalances. In this preliminary incomplete animal model, we aimed to introduce the idea of the possibility of scrotal urinary diversion via inguinal canal and speculate its clinical advantages with its low morbidity and surgical technique of human application. TECHNICAL CONSIDERATIONS: After a laporotomy and its left ureter dissection, a male rabbit underwent urinary diversion from kidney to the scrotum via catheter through the inguinal canal. Abdominal and scrotal incision closed with sutures but a potential gap was left at the scrotum for urinary leakage. Urinary leakage was observed from the ipsilateral scrotum postoperatively. THE HYPOTHESIS: Although this study can be regarded as just a hypothesis, we would like to introduce the idea of scrotal pouch as a urinary reservoir. We speculated that scrotal urinary diversion is better and applicable technique with many advantages and low morbidity, mortality and short operation time over the intestinal ones especially in selected patients. Further human studies may improve this novel technique.  相似文献   
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