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排序方式: 共有1006条查询结果,搜索用时 15 毫秒
81.
Regulatory functions of alloreactive Th2 clones in human renal transplant recipients 总被引:3,自引:0,他引:3
Kist-van Holthe JE Gasser M Womer K Najafian N Dong V Samsonov DV Geehan CS Chandraker A Sayegh MH Waaga AM 《Kidney international》2002,62(2):627-631
BACKGROUND: Chronic allograft rejection is the major clinical problem in organ transplantation. There is evidence that indirect T cell recognition of donor-specific HLA peptides may play an important role in the immunopathogenesis of chronic allograft rejection. We have recently shown that HLA allopeptide-specific T cell clones generated from renal transplant recipients with chronic allograft nephropathy are of the Th1 phenotype, while those from stable patients are Th2. There is evidence in experimental animal models of autoimmunity and transplantation that Th2 cells may function to regulate immune responses, but the biological relevance of these observations in humans has not been reported. METHODS: The purpose of this study was to investigate the putative regulatory functions of alloreactive human Th2 clones. HLA-DR allopeptide-specific Th1 and Th2 cell clones were generated from peripheral blood lymphocytes of human renal allograft recipients with chronic allograft nephropathy (CAN) or with stable renal function (SRF), respectively. RESULTS: An in vitro co-culture system showed that the proliferative responses of Th1 clones from patients with CAN were significantly inhibited by the Th2 clones in response to the donor-derived HLA allopeptides. In addition, co-culture of the Th2 clones inhibited cytokine production (IFN-gamma) by the Th1 clones in response to the donor-specific peptides. The regulatory functions of Th2 clones were antigen-specific since they only occurred when both the Th1 and Th2 clones were reactive to the same HLA-DR allopeptide, and were mediated by IL-4 and IL-10. CONCLUSIONS: This is the first demonstration, to our knowledge, indicating that Th2 cells may function to regulate indirect Th1 alloimmune responses that are critical for the progression of CAN in humans. 相似文献
82.
Moderate and severe malnutrition are endemic in much of the developing world and in association with pockets of deprivation in the developed world. The cost in terms of individual and social development is high. The principles of effective management are clearly documented. A low cost, community based treatment programme for moderately and severely malnourished children under 3 years of age was established at a health centre in rural Jamaica. Children were followed up monthly and defaulters were rigorously recalled. Management consisted of carefully delivered dietary advice, antibiotics, anthelminthics, and vitamin supplements. All children improved and the response of 36 children, who were treated in the first year, showed an accelerated weight gain, with catch-up growth and the maintenance of length gain. There was a significant increase in the weight for age, at 1.9% per month over six months, which exceeds the rate reported with food supplementation programmes and nutrition rehabilitation centres. 相似文献
83.
B. KAPPEL J. NIELSEN K. BROGAARD HANSEN M. MIKKELSEN AA. J. THERKELSEN 《BJOG : an international journal of obstetrics and gynaecology》1987,94(1):50-54
Summary. The clinical significance of placental perforation and bloodstained amniotic fluid was studied in a group of 7238 Danish women undergoing mid-trimester amniocentesis for prenatal diagnosis under ultrasound guidance. The risk of spontaneous abortion was significantly increased both in pregnancies where the placenta was perforated and in those with blood-stained amniotic fluid. The risk estimate nearly doubled after placental perforation and more than doubled with a bloody tap. It is concluded that for women at relatively low risk of a fetal genetic abnormality, the indication of the amniocentesis should be reconsidered if a placental perforation is unavoidable. 相似文献
84.
Parshikov VV Medvedev AP Samsonov AA Romanov RV Samsonov AV Gradusov VP Petrov VV Khodak VA Baburin AB 《Vestnik khirurgii imeni I. I. Grekova》2010,169(5):74-79
The article presents an experience with application of tension-free plasty of the anterior abdominal wall using reticular endoprostheses. New endoprostheses of Reperen are developed and applied, a method of sutureless fixation of polypropylene net in the abdominal wall tissues is proposed when performing plasty for great ventral hernias. Advantages of new methods are shown compared with analogs both in selective and in emergency surgery, in different age groups of patients. The direct and long-term postoperative results and parameters of quality of life are investigated. 相似文献
85.
WBG Macdonald AP Patrikeos RI Thompson BD Adler AA Van Der Schaaf 《Journal of Medical Imaging and Radiation Oncology》2005,49(1):32-38
The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses. 相似文献
86.
Maev IV Samsonov AA Vorob'ev LP Salova LM Zandanov AO Dronova OB 《Klinicheskaia meditsina》2000,78(6):39-42
Gastric secretion, motor function and tonicity of the stomach and duodenum, duodenogastric reflux were studied in inpatients with two clinicopathogenetic types of duodenal ulcer: observed at young age (type 1) and in later life (type 2). The examination included pH-metry with simultaneous balloon cimography, chromogastroduodenoscopy with Kongo-red, tests for Helicobacter pylori conducted on the biopsy samples. All the patients were found to have continuous acid production. High acid production was more frequently registered in males with the disease type 1, the lowest production was in females with the disease type 2. Duration of the acid inflow into the duodenum in patients with the disease type 2 was greater than that in young subjects. Mild ulcer was associated with moderate acidity in the duodenum, in severe ulcer the acidity was very high. Males with the disease 1 and 2 and females with type 2 had hyperkinetic, hypertonic gastric motor function. In duodenal ulcer prevalent is hypertonic, hyperkinetic type of duodenal motor function being most frequent among males with the disease type 2. Duodenogastric reflux occurs more often in patients with intensive acid production associated with hypotonic, hypokinetic motor type and duodenal tone. 相似文献
87.
Pathophysiologic considerations as well as non-comparative clinical results suggest that very high purity concentrates may slow immunologic deterioration in human immunodeficiency virus (HIV)-infected hemophiliacs. In an attempt to evaluate this hypothesis, we prospectively compared CD4 cell counts, skin testing responses, and changes of the clinical status in 20 asymptomatic HIV-positive hemophiliacs, randomly assigned to continue the treatment with an intermediate purity concentrate or to receive a very high purity product, purified by immunoaffinity chromatography with monoclonal antibodies. In the group switched to the very high purity concentrate there was no significant change of the CD4 cell counts over the 96-week follow-up period, whereas in the group continued on the intermediate purity concentrate, a highly significant decline was detected (P less than .013). Furthermore, in the very high purity group, four of six anergic patients at entry acquired reactivity to skin testing. The results of this study clearly support the use of very high purity concentrates for the replacement therapy of HIV-infected hemophiliacs. 相似文献
88.
89.
Direct demonstration of transsynaptic degeneration in the human visual system: a comparison of retrograde and anterograde changes 总被引:1,自引:0,他引:1 下载免费PDF全文
RM Beatty AA Sadun LEH Smith JP Vonsattel EP Richardson Jr 《Journal of neurology, neurosurgery, and psychiatry》1982,45(2):143-146
Transneuronal degeneration of retinal ganglion cells was directly demonstrated in a patient who had unilateral removal of the striate cortex forty years prior to necropsy. For comparison, another case is presented showing anterograde transneuronal atrophy forty years after enucleation of one eye. 相似文献