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161.
RG Lee K Nakamura AC Tsamandas K Abu-Elmagd H Furukawa WR Hutson J Reyes JS Tabasco-Minguillan S Todo AJ Demetris 《Gastroenterology》1996,110(6):1820-1834
BACKGROUND & AIMS: Intestinal transplantation is a developing therapeutic option for patients with irreversible intestinal failure or short bowel syndrome. The aim of this study was to delineate the histopathology of human intestinal allografts and to define the features of intestinal rejection. METHODS: The histological features of 3015 endoscopic biopsy specimens and 23 allograft specimens from 62 intestinal recipients were analyzed retrospectively and correlated with clinical findings. RESULTS: Acute allograft rejection was characterized by a varying combination of crypt injury, mucosal infiltration primarily by mononuclear cells (including blastic lymphocytes), and increased crypt cell apoptosis (more than 2 per 10 crypts). It represented a patchy, often ileal-centered process that could progress to mucosal ulceration; later episodes (more than 100 days posttransplant) tended to show lesser cellular infiltration and greater apoptosis than earlier episodes. Correlation with clinical rejection was good (false-positive rate of 9%; false-negative rate of 26%). Two resected specimens showed obliterative arteriopathy indicative of chronic rejection. In other specimens, preservation injury, cytomegalovirus infection, post-transplant lymphoproliferative disorder, and nonspecific features of active or past mucosal injury could be recognized. CONCLUSIONS: Mucosal biopsy specimens are a useful means of monitoring intestinal allografts. Based on features validated by clinical correlation, acute rejection can be identified reliably and can be differentiated from the other pathological processes affecting the intestinal allograft. (Gastroenterology 1996 Jun;110(6):1820-34) 相似文献
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Lorien M. Paulson Tyler S. Weaver Carol J. Macarthur 《International journal of pediatric otorhinolaryngology》2014
Objectives
Tympanostomy tubes are commonly used for treatment of chronic otitis media with effusion (COME) or recurrent acute otitis media (RAOM) in patients with Down syndrome, but hearing outcomes in this population have been mixed, and complications appear to be common. We aim to characterize outcomes and complications associated with tympanostomy tube placement in this population.Methods
Retrospective review. All patients with Down syndrome presenting to a tertiary academic pediatric otolaryngology practice over a ten year period from 2002 to 2012 who received tympanostomy tubes for COME, RAOM, or hearing loss were reviewed.Results
Long term follow up data was obtained in 102 patients, with average follow up 4.7 years. COME was the primary indication for tube placement in 100/102 (98%). Less than half of these patients (44%) initially failed their newborn hearing screen. Post operative hearing was found to be normal or near normal for the better hearing ear in 85/99 (85.9%), and normal to near normal in bilateral ears in 71/99 (71%). A majority (63.7%) of patients required two or more sets of tubes during the follow up period. Long term complications were common and were significantly increased if the patient required three or more sets of tubes, including chronic perforation (36.6% vs 8.2%, p < 0.001), atelectasis (29.3% vs 1.6%, p < 0.0001), and cholesteatoma (14.6% vs 0%, p = 0.003).Conclusions
COME is a frequent problem in Down syndrome, and the majority of patients will require two or more sets of tubes during their childhood and achieve normal postoperative hearing. Long term complications of otitis media appear to be more common in this population and appear to correlate with increasing number of tubes placed. More investigation is required to determine optimal treatment strategies for COME in patients with Down syndrome. 相似文献165.
<Emphasis Type="Italic">BRCA1</Emphasis> and <Emphasis Type="Italic">BRCA2</Emphasis> mutations in a population-based study of male breast cancer 下载免费PDF全文
Victoria?M?Basham Julian?M?Lipscombe Joanna?M?Ward Simon?A?Gayther Bruce?AJ?Ponder Douglas?F?Easton Paul?DP?PharoahEmail author 《Breast cancer research : BCR》2001,4(1):R2
Background
The contribution of BRCA1 and BRCA2 to the incidence of male breast cancer (MBC) in the United Kingdom is not known, and the importance of these genes in the increased risk of female breast cancer associated with a family history of breast cancer in a male first-degree relative is unclear.Methods
We have carried out a population-based study of 94 MBC cases collected in the UK. We screened genomic DNA for mutations in BRCA1 and BRCA2 and used family history data from these cases to calculate the risk of breast cancer to female relatives of MBC cases. We also estimated the contribution of BRCA1 and BRCA2 to this risk.Results
Nineteen cases (20%) reported a first-degree relative with breast cancer, of whom seven also had an affected second-degree relative. The breast cancer risk in female first-degree relatives was 2.4 times (95% confidence interval [CI] = 1.4–4.0) the risk in the general population. No BRCA1 mutation carriers were identified and five cases were found to carry a mutation in BRCA2. Allowing for a mutation detection sensitivity frequency of 70%, the carrier frequency for BRCA2 mutations was 8% (95% CI = 3–19). All the mutation carriers had a family history of breast, ovarian, prostate or pancreatic cancer. However, BRCA2 accounted for only 15% of the excess familial risk of breast cancer in female first-degree relatives.Conclusion
These data suggest that other genes that confer an increased risk for both female and male breast cancer have yet to be found.166.
JL Mokrosz B Duszyńska S Charakchieva-Minol AJ Bojarski MJ Mokrosz RL Wydra L Janda L Strekowski 《European journal of medicinal chemistry》1996,31(12):973-980
New N-methylpiperazino-substituted quinazolines 8 and 9, phthalazine 13, and quinoline 19 have been synthesized. The receptor binding profiles (α1, 5-HT1A, 5-HT2A) of these compounds and their analogs (7–22) have been determined. It has been demonstrated that orientation of a local dipole moment of the heteroaromatic ring system affects both the α1 and 5-HT2A affinity of the investigated class of ligands. Distortion of the coplanar unfused heteroaromatic ring system results in a decreased 5-HT2A affinity. 4-(4-Methylpiperazino)-2-(2-thienyl)quinoline 18 is the most active and selective α1 ligand (Ki = 4.9 nM) with a much lower affinity for 5-HT1A (Ki = 3420 nM) and 5-HT2A (Ki = 211 nM) receptors. 相似文献
167.
Production of immuno and biologically active erythropoietin was documented to occur in the human hepatoblastoma cell line HepG-2. The expression of the erythropoietin gene was further verified by Northern blot analysis using a single stranded RNA probe. In vitro studies showed that erythropoietin production by these cells was not stimulated by hypoxia or cobalt chloride, but was related to the proliferative activity of the cells in culture. In addition it was found that the secretion of erythropoietin was almost completely abrogated by tunicamycin, an inhibitor of N-linked glycosylation. This effect of tunicamycin was also observed in a permanently transfected cell line that secretes erythropoietin in large quantities. 相似文献
168.
AJ Wearden L Riste C Dowrick C Chew-Graham RP Bentall RK Morriss S Peters G Dunn G Richardson K Lovell P Powell 《BMC medicine》2006,4(1):1-12
Background
A major change has occurred in the last few years in the therapeutic approach to patients presenting with all forms of acute coronary syndromes. Whether or not these patients present initially to tertiary cardiac care centers, they are now routinely referred for early coronary angiography and increasingly undergo percutaneous revascularization. This practice is driven primarily by the angiographic image and technical feasibility. Concomitantly, there has been a decline in expectant or ischemia-guided medical management based on specific clinical presentation, response to initial treatment, and results of noninvasive stratification. This 'tertiarization' of acute coronary care has been fuelled by the increasing sophistication of the cardiac armamentarium, the peer-reviewed publication of clinical studies purporting to show the superiority of invasive cardiac interventions, and predominantly supporting (non-peer-reviewed) editorials, newsletters, and opinion pieces.Discussion
This review presents another perspective, based on a critical reexamination of the evidence. The topics addressed are: reperfusion treatment of ST-elevation myocardial infarction; the indications for invasive intervention following thrombolysis; the role of invasive management in non-ST-elevation myocardial infarction and unstable angina; and cost-effectiveness and real world considerations. A few cases encountered in recent practice in community and tertiary hospitals are presented for illustrative purposes The numerous and far-reaching scientific, economic, and philosophical implications that are a consequence of this marked change in clinical practice as well as healthcare, decisional and conflict of interest issues are explored.Summary
The weight of evidence does not support the contemporary unfocused broad use of invasive interventional procedures across the spectrum of acute coronary clinical presentations. Excessive and unselective recourse to these procedures has deleterious implications for the organization of cardiac health care and undesirable economic, scientific and intellectual consequences. It is suggested that there is need for a new equilibrium based on more refined clinical risk stratification in the treatment of patients who present with acute coronary syndromes. 相似文献169.
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