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41.
P. P. Singh Neelima Gupta Arun Goyal Sanjeev Tomar 《Indian journal of otolaryngology and head and neck surgery》2012,64(3):252-256
With this article we present our initial experience with interventional sialendoscopy of the parotid duct for the parotid calculi. We carried out a prospective study of patients of parotid calculi in a tertiary referral centre. Diagnostic and interventional sialendoscopy was performed in five cases of parotid calculi. The outcome was classified on the basis of clearance of the lumen of the duct and resolution of symptoms. Diagnostic sialendoscopy was able to diagnose the calculus in all cases. Interventional sialendoscopy was done under general anesthesia in all cases and calculus was successfully removed. The average size of sialolith was 8.2 mm. No complications occurred in any of the cases. Check sialendoscopy was done in all cases after a minimum follow up of 6 months, which showed the duct lumen to be free of stone with no stricture of the duct. Sialendoscopy is an optimal technique for removal of intraductal parotid calculi and avoids removal of the gland. In our series there was no associated morbidity and complication. 相似文献
42.
Mahesha Weerakoon Shomik Sengupta Kapil Sethi Joseph Ischia David R. Webb 《Journal of robotic surgery》2012,6(4):311-316
Robot-assisted laparoscopic radical prostatectomy (RALRP), increasingly used to treat localized prostate cancer, has advantages over open radical prostatectomy (ORP) in terms of reduced bleeding and quicker convalescence. However, debate continues over whether RALRP provides superior or at least equivalent surgical outcomes. This study compares positive surgical margins (+SM), as a surrogate for long-term cancer control, at RALRP and ORP performed by a single experienced surgeon during the process of taking up RALRP. 400 consecutive patients undergoing surgery for prostate cancer under a single surgeon (DW) between November 1999 and July 2009 were studied. Prior to July 2005, all patients underwent ORP; after this date, most patients were treated by RALRP. Data were collected by retrospective chart review and analysed independently of the treating surgeon. +SM were defined as the presence of cancer at an inked surface. Overall, 23 (11.5%) of 200 patients undergoing RALRP had +SM, compared to 40 (20.0%) of 200 patients undergoing ORP (P?<?0.05). On univariate logistic regression analysis, in addition to surgical approach (odds ratio [OR]?=?1.92), patient age (OR?=?1.05), pathologic stage (OR?=?3.93) and specimen Gleason (GS) score (OR?=?1.86) were significant predictors of +SM. On multivariate analysis, surgical approach, p-stage and specimen GS remained significant predictors of +SM. RALRP is associated with lower rates of +SM compared to ORP, even after adjusting for other known risk factors. Of note, the RALRP in this study were part of the surgeon??s learning curve. 相似文献
43.
Bangkim Chandra Khangembam MD Niraj Naswa MD Punit Sharma MD Chandrasekhar Bal MD Arun Malhotra MD PhD Rakesh Kumar MD PhD 《Journal of nuclear cardiology》2012,19(5):1078-1079
We present an interesting image that demonstrates utility of 68Ga-DOTANOC PET/CT for demonstrating rare metastatic sites of neuroendocrime tumor. 相似文献
44.
45.
A micro-level investigation of 983 pregnant women (aged 15–49 years) regarding sex determination and associated factors was carried out in a periurban region of Northern India. Among the women surveyed, 183 chose to use sex determination. The highest percentage of sex determination was among 30–39-year-old women, and general caste and family size were two risk factors associated with sex determination. Correcting imbalances in sex ratios at birth is a complex issue without easy answers, especially in patriarchal societies. Apart from raising awareness among decisionmakers, property rights in favor of women and strict vigilance and record of registration of ultrasound machines are necessary. 相似文献
46.
Dahai Gao Shishir P. S. Chundawat Anurag Sethi Venkatesh Balan S. Gnanakaran Bruce E. Dale 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(27):10922-10927
Substrate binding is typically one of the rate-limiting steps preceding enzyme catalytic action during homogeneous reactions. However, interfacial-based enzyme catalysis on insoluble crystalline substrates, like cellulose, has additional bottlenecks of individual biopolymer chain decrystallization from the substrate interface followed by its processive depolymerization to soluble sugars. This additional decrystallization step has ramifications on the role of enzyme–substrate binding and its relationship to overall catalytic efficiency. We found that altering the crystalline structure of cellulose from its native allomorph Iβ to IIII results in 40–50% lower binding partition coefficient for fungal cellulases, but surprisingly, it enhanced hydrolytic activity on the latter allomorph. We developed a comprehensive kinetic model for processive cellulases acting on insoluble substrates to explain this anomalous finding. Our model predicts that a reduction in the effective binding affinity to the substrate coupled with an increase in the decrystallization procession rate of individual cellulose chains from the substrate surface into the enzyme active site can reproduce our anomalous experimental findings. 相似文献
47.
Breast cancers that are found and confirmed because they are causing symptoms tend to be larger and are more likely to have already spread to the lymph nodes and beyond. Thus, early detection and confirmation are of paramount importance. The normalized axial–shear strain area (NASSA) feature from the axial-shear strain elastogram (ASSE) has been shown to be a feature that can identify the boundary-bonding conditions that are indicative of the presence of cancer. Recently, we investigated and reported on the potential of the NASSA feature for breast lesion classification into fibroadenomas and cancers. In this article, we investigate the size distribution of the lesions that were part of the previous study and analyze classification performance specifically on small lesions (<10 mm diameter). A total of 33 biopsy-proven malignant tumors and 30 fibroadenomas were part of the study that involved three observers blinded to the Breast Imaging Reporting and Data System (BIRADS) ultrasound scores. The observers outlined the lesions on the sonograms and the lesion size (maximum circle-equivalent diameter in millimeters) was computed from this outline. The ASSE was automatically segmented and color-overlaid on the sonogram, and the NASSA feature from ASSE was computed semi-automatically. Receiver operating characteristic curves were then generated for the subset of cases involving small lesions. Box plots were produced for the two different lesion size groups, small and large, from a logistic regression classifier that was built previously. The results of our study show that approximately 38% and 22% of the fibroadenomas and cancers, respectively, were small. Furthermore, it was found that the NASSA feature resulted in a perfect classification of the small lesions, both in the training data and in the cross-validation. For lesions <10 mm the difference in fibroadenoma and cancer mean scores was 0.73 ± 0.13 (p < 0.001), whereas lesions >10 mm had a difference of 0.52 ± 0.24 (p < 0.001). The results also showed that the small lesions actually had better classification than the larger lesions (>10 mm). These results suggest that the ASSE feature can work equally well, even on small lesions, to improve the standard ultrasound BIRADS–based breast lesion classification of fibroadenoma and malignant tumors. 相似文献
48.
Clinical and histologic spectrum of nonalcoholic fatty liver disease associated with normal ALT values 总被引:34,自引:0,他引:34
Mofrad P Contos MJ Haque M Sargeant C Fisher RA Luketic VA Sterling RK Shiffman ML Stravitz RT Sanyal AJ 《Hepatology (Baltimore, Md.)》2003,37(6):1286-1292
A retrospective study was performed to (1) characterize the clinical and histologic features of those with nonalcoholic fatty liver disease (NAFLD) and normal alanine aminotransferase (ALT) values, (2) compare the spectrum of NAFLD associated with normal versus elevated ALT levels, and (3) determine whether there were differences in the clinical or histologic spectrum of NAFLD between those with a low normal versus high normal ALT value. A total of 51 subjects with NAFLD and normal ALT were identified and compared with 50 consecutive subjects with NAFLD and elevated ALT. The major indications for liver biopsy in those with normal ALT were unexplained hepatomegaly (n = 21) and evaluation as a potential donor for living donor liver transplantation (n = 16). The 2 groups were comparable with respect to age, gender distribution, and ethnicity. Approximately 80% of cases in both groups had at least 1 feature of the metabolic syndrome, the major risk factor for NAFLD. The 2 groups were also comparable with respect to the grade of the individual histologic parameters of NAFLD. A total of 12 subjects with normal ALT levels had bridging fibrosis, whereas 6 had cirrhosis. Diabetes was the only factor independently associated with an increased risk of advanced fibrosis (bridging fibrosis or cirrhosis) by multivariate analysis (relative risk: 2.3, P <.01). The mean steatosis (1.6 vs. 2.16, P <.04) and perisinusoidal fibrosis scores (0.35 vs. 0.9, P <.049) were lower in those with low normal (<30 IU/L) ALT versus high normal ALT. However, the prevalence of advanced fibrosis was similar (5 of 15 vs. 13 of 36, respectively). In conclusion, (1) the entire histologic spectrum of NAFLD can be seen in individuals with normal ALT values, (2) the histologic spectrum in these individuals is not significantly different from those with elevated ALT levels, and (3) a low normal ALT value does not guarantee freedom from underlying steatohepatitis with advanced fibrosis. 相似文献
49.
Upendra Kaul Ripen K Gupta Kottaram K Haridas Saligrama S Ramesh Kamal K Sethi Balbir Singh Rajiv Agarwal Ram D Yadave Tapan Ghose Rakesh R Sapra Rajiv Bajaj Madhukar Shahi Ajit Bhagwat Pramod Kumar Omen P Mathews Pratik K Soni 《Catheterization and cardiovascular interventions》2002,57(4):497-503
The results of primary coronary stenting for acute myocardial infarction (AMI) have been reported to improve significantly with the concomitant administration of platelet glycoprotein IIb/IIIa inhibitor abciximab. There are, however, no data available with the use of eptifibatide, a more cost-effective, small-molecule GP IIb/IIIa blocker with a shorter half-life. In a prospective multicenter feasibility and efficacy study, we assigned 55 consecutive patients with AMI being taken up for primary stenting to receive eptifibatide just before the procedure (two boluses of 180 microg/kg 10 min apart and a 24-hr infusion of 2 microg/kg/min). Clinical outcomes were evaluated at 30 days after the procedure. The angiographic patency of the vessel with TIMI flow rates, TIMI myocardial perfusion (TMP) grade, and corrected TIMI frame counts were assessed at the end of procedure and before hospital discharge. At 30 days, the primary endpoint, a composite of death, myocardial infarction, and urgent target vessel revascularization (TVR) was seen in 12.7% of patients. The TIMI 3 and TMP grade 3 flow, which was seen in 93% and 86% of patient, respectively, at the end of the procedure, declined to 86% and 78%, respectively (P < 0.05) before hospital discharge. Corrected TIMI frame counts also decreased from 25.7 +/- 7.2 to 22.9 +/- 6.8 (P < 0.05). There were five (9.1%) instances of subacute thrombosis (SAT) presenting as AMI, needing urgent TVR in all, within 3-5 days of the primary procedure. No excessive bleeding complication, directly attributable to the use of eptifibatide, was observed. The study was terminated prematurely because of an unacceptable SAT rate. Administration of eptifibatide along with primary stenting for AMI is associated with a high TIMI 3 and TMP grade 3 flow acutely. However, these flows decline significantly before hospital discharge and lead to a high rate of SAT. The dosage and duration of infusion of eptifibatide in this setting needs further evaluation. 相似文献
50.
Prime K Sethi G Navaratne L Dean G Fox E Sabin C Taylor C de Ruiter A Taylor G Edwards S 《AIDS (London, England)》2003,17(2):260-262
Our findings show a high rate of loss to follow-up in HIV-positive teenagers compared with adults. Of concern is the fact that this group also have high rates of sexually transmitted infections, unprotected sex and pregnancy. There is an urgent need to examine the reasons for this and adopt strategies to minimize risk-taking behaviour and to improve access to appropriate healthcare. 相似文献