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1.
F. F. Isik T. O. McDonald M. Ferguson E. Yamanaka D. Gordon 《The American journal of pathology》1992,141(5):1139-1149
Transplant arteriosclerosis (TA) has emerged as an obstacle to the long-term survival of transplanted organs, especially cardiac transplants. The animal models that have been used to study TA have not been fully characterized with regard to features such as the time course of cell proliferation and the sequence of cell types arriving in the developing intimal lesion. We present a model of TA based on a transplanted segment of abdominal aorta that helps address these questions. Two strains of rats (PVG x DA) underwent orthotopic aortic transplantation without immunosuppression and were killed at 14, 20, 40, and 60 days after transplantation. The within-strain control group displayed minimal evidence of cellular rejection with minimal to absent intimal lesions. In contrast, the allograft group showed a linearly increasing intimal lesion, up through 60 days after transplantation. The mechanism of intimal thickening was by an increase in cell number at the earlier time points with the later deposition of extracellular matrix. The early intimal lesion consisted mostly of mononuclear inflammatory cells (45%) with gradually increasing presence of smooth muscle cells (SMC) in the intima between 20 and 60 days. Conversely, the media showed gradual infiltration by macrophage-type cells with virtual loss of all SMC from the media by 40 days. The proliferative index showed a peak of 6% and 8% at 20 days in both the intima and media, respectively, and was preceded by the presence of macrophages. In fact, most of the proliferating cells at the earlier time points were either monocytes/macrophages, or were immediately adjacent to monocyte-/macrophage-rich regions. This straight artery segment model of transplant arteriosclerosis provides an easily quantifiable system in which the effects of different interventions (e.g., immunosuppressive regimens) can be tested. 相似文献
2.
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
3.
Tasdemir Murat; Tasdemir Isik; Kodama Hideya; Tanaka Toshinobu 《Human reproduction (Oxford, England)》1993,8(12):2102-2107
To evaluate the possible effect of pentoxifylline on the acrosomereaction (AR) and its correlation with in-vitro fertilization(IVF), sperm samples obtained from 51 patients who underwentIVF treatment were studied. Acrosome reactions were evaluatedas spontaneous, pentoxifylline-treated and calcium ionophore(A23187) induced, before and after treatment. The correlationof AR with fertilization in vitro in spermatozoa pre-treatedwith pentoxifylline was sought. In cases with failure or verylow fertilization rate (10%) in their previous trials, spermatozoaafter swim-up were treated before insemination. Spontaneousacrosome loss remained low even after treatment (mean ±SD: 8.18 ± 1.74%). Response to A23187 was enhanced significantly(P < 0.001) by pre-treatment with pentoxifylline in 33 controlcases (group A) in which fertilization in vitro was previouslysuccessful without this treatment. Patients with at least twoepisodes of failed fertilization were divided into two groups.In 11 cases (group B), the IVF rate was improved significantly(P < 0.001) by the treatment. This was not observed in sevencases (group C) in which the treatment induced no increase inIVF rate. We achieved nine (27.3%) pregnancies in group A andfive (45.4%) pregnancies in group B. This study demonstratedthat pentoxifylline enhanced A23187 induced the acrosome reactionand this effect was correlated with improvement in IVF rate. 相似文献
4.
Inhibition of Antibody-Dependent Human Lymphocyte-Mediated Cytotoxicity by Immunoglobulin Classes, IgG Subclasses, and IgG Fragments 总被引:11,自引:0,他引:11
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
5.
Striated intramural gallbladder lucencies on US studies: predictors of acute cholecystitis 总被引:1,自引:0,他引:1
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
6.
C Camenzuli AN DiMarco KE Isaacs Y Grant J Jackson A Alsafi C Harvey TD Barwick N Tolley FF Palazzo 《Annals of the Royal College of Surgeons of England》2021,103(1):29
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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9.
Güler Kanra Pinar Isik Ates Kara Ali Bülent Cengiz Gülten Seçmeer Mehmet Ceyhan 《Pediatrics international》2004,46(6):663-668
BACKGROUND: Mumps vaccine has not yet been included in the routine vaccination programme, for this reason mumps is still one of the most common infections for children in Turkey. One of the major complication of mumps is meningoencephalitis, which although usually heals spontaneously, it may cause neurologic complications. METHODS: This study was undertaken to investigate epidemiologic and demographic characteristics in children with mumps and mumps meningoencephalitis and clinical/laboratory findings in children with mumps meningoencephalitis diagnosed over a 11 year period. A total of 2422 mumps and 135 mumps meningoencephalitis cases were covered in this study which constitutes one of the largest series of mumps meningoencephalitis in the literature. The mean age of mumps and mumps meningoencephalitis cases were 6.6 +/- 2.7 and 7.6 +/- 2.6 years, respectively. RESULTS: There was a male predominance both among the cases of mumps and mumps meningoencephalitis. The age and seasonal distributions were similar in the mumps and mumps meningoencephalitis groups. The most common symptoms of mumps meningoencephalitis were fever (97%), vomiting (94%) and headache (88.8%). The mean cerebrospinal fluid (CSF) total cell count and lymphocyte count were 540 +/- 460/mm(3) and 300 +/- 330/mm(3), respectively. The mean CSF protein and glucose levels were found to be 56.97 +/- 27.94 mg/dL and 53.67 +/- 15.46 mg/dL, respectively. The mean of CSF/blood glucose ratio was 0.53 +/- 0.16. The mean duration of hospitalization in mumps meningoencephalitis cases was found to be 5.1 +/- 2.4 days and this was longer in boys (P < 0.05). CONCLUSION: In patients with mumps meningoencephalitis, higher CSF protein levels and lower CSF glucose/blood glucose ratio were associated with longer hospitalization periods. There was no death. 相似文献
10.
Ayse Rodopman Arman Pinar Ay Nese Perdahli Fis Refika Ersu Ahmet Topuzoglu Ugur Isik Meral Berkem 《Acta paediatrica (Oslo, Norway : 1992)》2011,100(3):420-424
Aim: In this population‐based study, we aimed to determine the total sleep duration (TSD), its association with socio‐economic status (SES) and behavioural symptoms among schoolchildren. Methods: A cross‐sectional study was performed among schoolchildren in Istanbul. A structured questionnaire evaluating the sleep schedule variables was filled out by their parents. SES was determined according to the Turkish SES scale. Results: The mean age of 2669 children was 8.2 ± 2.4 years, and 51% of the students were girls. The mean TSD was 10.20 ± 1.04, and the mean bedtime was 21.57 ± 0.56 (both in hours, minutes ± SD). Boys tended to go bed later (p = 0.004) and slept less than girls (p = 0.02). The duration of sleep disruptions increased (p < 0.001), whereas TSD decreased with age (p < 0.001). Multiple linear regression revealed that waking time and TSD decreased significantly (p < 0.05) with higher SES among both girls and boys. Sleep fragmentation was associated with habitual snoring, parasomnias, daytime sleepiness and conduct symptoms. Conclusion: Decreased total sleep duration is more prominent in boys, older children and children among higher socio‐economic status. Insufficient sleep attributed to shortened total sleep duration by age and higher socio‐economic status might have a negative effect on both sleep hygiene and psychological well‐being in schoolchildren. 相似文献