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31.
A. Sagayaraj R. P. Deo S. M. Azeem Mohiyuddin G. Oommen Modayil 《Indian journal of otolaryngology and head and neck surgery》2012,64(3):270-274
The aim of this study is to conceive a method of raising an island PMMC flap, so as to circumvent its drawbacks of bulk, flap length and the difficulty of developing this flap in female patients. And to consider island PMMC flap as a viable reconstructive option in head and neck surgeries, especially in peripheral centres. Ours is an experimental case series. The study was done at Sri Devaraj URS Medical college, Tamaka, Kolar. Between 2009 and 2010, head and neck reconstruction was performed using this method in 20 patients who had oral cancer (18), carcinoma supraglottis (1) and mucoepidermoid carcinoma parotid (1). The patients age ranged from 16 to 75 years, and there were 15 women and 5 men. Nineteen of our patients underwent primary surgery and one patient was operated for residual disease. In (16) patient, island pmmc flap was used for intra oral closure. In (4) patients the flap was spiraled for providing skin cover. Four patients developed complications. Three were minor complications of margin necrosis and wound dehiscence, which were managed conservatively. One patient developed orocutaneous fistula, which required secondary suturing. None of our patients had a total necrosis of the flap. Island PMMC flap is still a very useful and viable option for reconstruction in head and neck surgeries, especially in lateral gingivo buccal tumours and other head and neck tumours. In institutions where microvascular expertise is not available, island PMMC flap can be an alternative with results comparable to that of free tissue transfer. 相似文献
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Decreased expression of phospholipase C-beta 2 isozyme in human platelets with impaired function 总被引:4,自引:4,他引:4
Platelets from a patient with a mild inherited bleeding disorder and abnormal platelet aggregation and secretion show reduced generation of inositol 1,4,5-trisphosphate, mobilization of intracellular Ca2+, and phosphorylation of pleckstrin in response to several G protein mediated agonists, suggesting a possible defect at the level of phospholipase C (PLC) activation (see accompanying report). A procedure was developed that allows quantitation of platelet PLC isozymes. After fractionation of platelet extracts by high-performance liquid chromatography, 7 out of 10 known PLC isoforms were detected by immunoblot analysis. The amount of these isoforms in normal platelets decreased in the order PLC- gamma 2 > PLC-beta 2 > PLC-beta 3 > PLC-beta 1 > PLC-gamma 1 > PLC- delta 1 > PLC-beta 4. Compared with normal platelets, platelets from the patient contained approximately one-third the amount of PLC-beta 2, whereas PLC-beta 4 was increased threefold. These results suggest that the impaired platelet function in the patient in response to multiple G protein mediated agonists is attributable to a deficiency of PLC-beta 2. They document for the first time a specific PLC isozyme deficiency in human platelets and provide an unique opportunity to understand the role of different PLC isozymes in normal platelet function. 相似文献
36.
Emma C Richards Thomas E Cowling Elinor J Gunning Matthew J Harris Michael A Soljak Naomi Nowlan Kanika Dharmayat Nur Johari Azeem Majeed 《The British journal of general practice》2015,65(641):e806-e812
Background
The NHS Choices website (www.nhs.uk) provides data on the opening hours of general practices in England. If the data are accurate, they could be used to examine the benefits of extended hours.Aim
To determine whether online data on the opening times of general practices in England are accurate regarding the number of hours in which GPs provide face-to-face consultations.Design and setting
Cross-sectional comparison of data from NHS Choices and telephone survey data reported by general practice staff, for a nationally representative sample of 320 general practices (December 2013 to September 2014).Method
GP face-to-face consultation times were collected by telephone for each sampled practice for each day of the week. NHS Choices data on surgery times were available online. Analysis was based on differences in the number of surgery hours (accounting for breaks) and the times of the first and last consultations of the day only between the two data sources.Results
The NHS Choices data recorded 8.8 more hours per week than the survey data on average (40.1 versus 31.2; 95% confidence interval [CI] = 7.4 to 10.3). This was largely accounted for by differences in the recording of breaks between sessions. The data were more similar when only the first and last consultation times were considered (mean difference = 1.6 hours; 95% CI = 0.9 to 2.3).Conclusion
NHS Choices data do not accurately measure the number of hours in which GPs provide face-to-face consultations. They better record the hours between the first and last consultations of the day. 相似文献37.
38.
Signal transduction on platelet activation involves phosphoinositide- specific phospholipase C (PLC)-mediated hydrolysis of phosphatidylinositides and formation of inositol-1,4,5-triphosphate [I(1,4,5)P3], which mediates Ca2+ mobilization, and diacylglycerol (DG), which activates protein kinase C (PKC) to phosphorylate a 47-kD protein (Pleckstrin). We studied these events in two related patients previously reported (Blood 74:664, 1989) to have abnormal aggregation and 14C-serotonin secretion, and impaired intracellular Ca2+ mobilization in response to several agonists. Thrombin-induced I(1,4,5)P3 and phosphatidic acid formation were diminished. Pleckstrin phosphorylation was impaired on activation with thrombin, platelet- activating factor, and ionophore A23187, but was normal with PKC activator 1,2-dioctonyl-sn-glycerol (DiC8). Ca2+ mobilization induced by guanosine triphosphate (GTP) analog guanosine 5'-0-(3 thiotriphosphate) (GTP gamma S) was diminished. Pretreatment with either A23187 or DiC8 did not correct the impaired adenine diphosphate- induced secretion; however, upon stimulation with A23187 plus DiC8, pleckstrin phosphorylation and secretion were normal, indicating that both PKC activation and Ca2+ mobilization are essential for normal secretion. We conclude that these patients have a unique inherited platelet defect in formation of two key intracellular mediators [I(1,4,5)P3 and DG] and in the responses mediated by them due to a defect in postreceptor mechanisms of PLC activation. 相似文献
39.
Immunoglobulin V regions and the B cell 总被引:7,自引:2,他引:7
40.
Importance of specimen size in accurate needle liver biopsy evaluation of patients with chronic hepatitis C. 总被引:1,自引:0,他引:1
Thomas D Schiano Samia Azeem Carol A Bodian Henry C Bodenheimer Sukma Merati Swan N Thung Prodromos Hytiroglou 《Clinical gastroenterology and hepatology》2005,3(9):930-935
BACKGROUND & AIMS: In patients with chronic hepatitis C (CHC), percutaneous needle liver biopsy examination establishes the severity of necroinflammatory activity and fibrosis, thus guiding treatment decisions. Optimal biopsy specimen size remains controversial. We sought to determine how varying lengths of biopsy specimens influence the grading and staging of CHC. METHODS: We used 100 liver biopsy specimens from patients with CHC. The slides were evaluated blindly using the METAVIR scoring system, after being covered with paper, so that only specific specimen lengths (5 mm, 10 mm, 15 mm, and > or =20 mm) were visible. In each case, the scores obtained with biopsies 5 mm, 10 mm, or 15 mm long were compared with the scores at 20 mm or greater by weighted kappa statistics (kappa of >.75 signified excellent agreement). A subset of specimens 20 mm or greater was selected for a blinded repeat scoring to assess intraobserver agreement. The kappa statistics for the designated features and lengths were compared using analysis of variance. RESULTS: In assessing the stage of fibrosis, the weighted kappa statistics for agreement with the 20-mm or greater score at 5 mm, 10 mm, and 15 mm were .75, .85, and .92, respectively. In assessing the histologic activity score, the corresponding figures were .73, .81, and .77, respectively. Average kappa statistic comparisons showed that intraobserver agreement was significantly better than agreement between the 20-mm or greater scores and those at shorter lengths; the 5-mm kappa scores were significantly lower than the others; and there was no significant difference between the 10-mm and 15-mm kappa scores. CONCLUSIONS: Liver biopsy specimens measuring at least 10 mm usually reflect the grade and stage of CHC reliably. Relatively little improvement in diagnostic accuracy is obtained with longer specimens. 相似文献