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91.
Kelly E. Michaelsen Venkataramanan Krishnaswamy Linxi Shi Srinivasan Vedantham Steven P. Poplack Andrew Karellas Brian W. Pogue Keith D. Paulsen 《Biomedical optics express》2015,6(12):4981-4991
Calibration of a three-dimensional multimodal digital breast tomosynthesis (DBT) x-ray and non-fiber based near infrared spectral tomography (NIRST) system is challenging but essential for clinical studies. Phantom imaging results yielded linear contrast recovery of total hemoglobin (HbT) concentration for cylindrical inclusions of 15 mm, 10 mm and 7 mm with a 3.5% decrease in the HbT estimate for each 1 cm increase in inclusion depth. A clinical exam of a patient’s breast containing both benign and malignant lesions was successfully imaged, with greater HbT was found in the malignancy relative to the benign abnormality and fibroglandular regions (11 μM vs. 9.5 μM). Tools developed improved imaging system characterization and optimization of signal quality, which will ultimately improve patient selection and subsequent clinical trial results.OCIS codes: (120.3890) Medical optics instrumentation, (170.0110) Imaging systems, (170.3830) Mammography 相似文献
92.
93.
Jeremy S. Somerson Daniel J. Fletcher Ramesh C. Srinivasan David P. Green 《Hand (New York, N.Y.)》2015,10(3):450-453
Purpose
Bone graft is often recommended as an adjuvant for treatment of scaphoid nonunions. However, recent literature has suggested that fibrous nonunion may be suited to treatment with rigid fixation without bone grafting. This work reported on outcomes of compression screw fixation for established scaphoid fibrous nonunions without bone graft.Methods
Fourteen patients underwent surgical compression screw fixation without bone grafting of scaphoid fibrous nonunion between January 1, 2000, and December 31, 2012, with minimum follow-up until the time of clinical and radiographic healing. Fibrous nonunion of the scaphoid was defined as a scaphoid fracture with all of the following features: (1) persistent tenderness, (2) incomplete trabecular bridging on three X-ray views, (3) injury that had occurred at a minimum of 6 months prior to surgery, and (4) identification of fibrous union at the time of surgery. Outcomes were assessed with range of motion assessment, Disability of the Arm, Shoulder and Hand (DASH) scores, and plain radiographs.Results
Twelve of the 14 patients healed successfully, while two patients required secondary vascularized bone grafting. Both unhealed patients sustained proximal pole fractures and had a duration of ≥1 year from injury to surgery. Average time to healing was 4.4 ± 2.0 months. Average flexion was 73 ± 22° and average extension was 66 ± 22° postoperatively. Average grip strength was 90 ± 25 lbs on the operative side. Mean postoperative pain score was 1.4 (range, 0 to 7). Mean postoperative DASH score was 10.2 (range, 0 to 52). Increasing age and an interval from injury to surgery of >1 year correlated with worse DASH and pain scores.Conclusions
Patients with fibrous scaphoid nonunion demonstrated good results with rigid fixation without bone grafting. Increasing age and >1-year interval between injury and surgery resulted in lower self-assessed outcomes.Level of Evidence
Therapeutic Level IV, retrospective case series 相似文献94.
Risk factors in early life as predictors of adult heart disease: the Bogalusa Heart Study 总被引:6,自引:0,他引:6
G S Berenson S R Srinivasan S M Hunter T A Nicklas D S Freedman C L Shear L S Webber 《The American journal of the medical sciences》1989,298(3):141-151
The adult heart diseases, coronary artery disease and essential hypertension, are now clearly recognized to begin in childhood. The evidence comes from autopsy studies of cardiovascular-renal changes in the first two decades of life. Cardiovascular risk factors can be identified in children just as in adults and these have a high correlation with the anatomic disease. This relationship underscores the importance of risk factor screening of children. Of interest is that clinical risk factors tend to persist within a rank (track) so that studies in childhood can be predictive of future levels. Behavior and lifestyle of eating, cigarette smoking, alcohol intake, and use of oral contraceptive pills influence risk factors in children. Familial aggregation of risk factors are also noted. Studies of apolipoproteins, B and A-I, have identified subsets of children that have a greater frequency of paternal myocardial infarction. The findings from the Bogalusa Heart Study and other epidemiological studies of children show the need to begin prevention of adult heart disease in early life. Approaches to prevention should include high risk families and children and a public health or population approach. Cardiovascular health education for elementary school children should be directed to children in the general population in an effort to encourage them to adopt healthy life styles. 相似文献
95.
In recent decades, there has been a dramatic increase in the incidence of obesity in all age groups of the population in the USA. In addition to genetics and life style changes, the important role of metabolic programming effects in the etiology of the obesity epidemic is being increasingly recognized. Although the role of a compromised intrauterine environment in fetal metabolic programming is well documented to contribute to the development of adult-onset diseases, vulnerability in the immediate postnatal period to similar conditions has also been shown. Metabolic programming effects induced by altered nutritional experiences in the immediate postnatal period can give rise to long-term consequences in the context of the current obesity epidemic. 相似文献
96.
Pulimood AB Ramakrishna BS Rita AB Srinivasan P Mohan V Gupta S Perakath B Kang G Chandy G Balasubramanian KA 《Journal of gastroenterology and hepatology》2008,23(5):752-758
Background and Aim: Macrophages and dendritic cells are closely related mononuclear phagocytic cells. Little is known about their in vivo role in acute intestinal bacterial infections in humans. We undertook to evaluate these cells in rectal mucosal biopsies of patients with acute colitis. Methods: All mucosal mononuclear phagocytic cells in rectal biopsies of patients with acute Campylobacter colitis (n = 5), shigellosis (n = 5), and cholera (n = 10) were evaluated ultrastructurally and compared with those in controls (n = 5). Results: Mononuclear phagocytic cells in the superficial rectal mucosa showed a higher prevalence of ultrastructural features of activation in Campylobacter colitis and cholera than in controls. A lower prevalence of features of activation with increased monocytes was seen in shigellosis. Cells with the ultrastructural morphology of activated dendritic cells constituted 41% and 45% of all mononuclear phagocytic cells in two of five patients with Campylobacter colitis and 4–22% of cells in four of 10 patients with cholera. Their presence in patients with Campylobacter colitis was associated with significant surface epithelial damage and prominent acute inflammatory changes in the mucosa. Conclusions: This is the first ultrastructural study to show activated macrophages and dendritic cells in vivo in acute Campylobacter colitis and cholera. Dendritic cell activation occurred early in the clinical course of these infections. Surface epithelial damage may play a role in the activation of dendritic cells. 相似文献
97.
Abhijit Chougule Shreya Srivastava Sidharth Totadri Radhika Srinivasan Amita Trehan 《Diagnostic cytopathology》2015,43(12):1000-1002
Multinucleated giant cells of osteoclastic type are known to occur in nodal and extranodal lesions of Langerhans cell histiocytosis (LCH). These giant cells are thought to be derived from phagocytic histiocytes, which correlate with the degree of necrosis in LCH lesions. Emperipolesis commonly seen in Rosai–Dorfman disease is a distinct phenomenon characterized by intact phagocytosed cells in an intracytoplasmic vacuole protected from proteolytic digestion. We present a case of emperipolesis of inflammatory cells especially of eosinophils by multinucleated giant cells of Langhans type in a lymph node involved by LCH—a finding that has not been described previously in the literature. Diagn. Cytopathol. 2015;43:1000–1002. © 2015 Wiley Periodicals, Inc. 相似文献
98.
99.
Srinivasan Jayaraman 《Journal of Indian Prosthodontic Society》2015,15(2):179-182
The failure of dental implant can occurs at the preoperative planning stage, at the surgical stage, and at the postoperative stage. The success of this treatment can be increased if the clinical implant practice guidelines are prepared based on the recommendations from the highest level of research evidence (i.e.,) from systematic review of randomized controlled trials (RCTs) with meta-analysis. The Cochrane reviews of interventions are basically systematic reviews of RCTs with meta-analysis but follow a systematic methodological approach following the guidelines from Cochrane handbook for Systematic Reviews of Intervention. They give the current best evidence as they are updated every 2 years which is being the minimum period for an update. This evidence summary recommends the use of antibiotics, single dose of 2 g of amoxicillin 1 h prior to implant surgery to prevent implant failure, based on the body of evidence from the Cochrane review that was first published in 2003, 2008, and then updated twice in 2010 and 2013. The included studies are not from our population for the research question asked in this updated Cochrane review; hence, the need to do primary research in our population to support the available evidence is mandatory.Key Words: Antibiotics, evidence summary, implant placement 相似文献
100.
Srinivasan Sakthivel Andrea Zatkova Martina Nemethova Milan Surovy Ludevit Kadasi Madurai P. Saravanan 《Annals of human genetics》2014,78(3):155-164
Alkaptonuria (AKU) is an autosomal recessive disorder; caused by the mutations in the homogentisate 1, 2‐dioxygenase (HGD) gene located on Chromosome 3q13.33. AKU is a rare disorder with an incidence of 1: 250,000 to 1: 1,000,000, but Slovakia and the Dominican Republic have a relatively higher incidence of 1: 19,000. Our study focused on studying the frequency of AKU and identification of HGD gene mutations in nomads. HGD gene sequencing was used to identify the mutations in alkaptonurics. For the past four years, from subjects suspected to be clinically affected, we found 16 positive cases among a randomly selected cohort of 41 Indian nomads (Narikuravar) settled in the specific area of Tamil Nadu, India. HGD gene mutation analysis showed that 11 of these patients carry the same homozygous splicing mutation c.87 + 1G > A; in five cases, this mutation was found to be heterozygous, while the second AKU‐causing mutation was not identified in these patients. This result indicates that the founder effect and high degree of consanguineous marriages have contributed to AKU among nomads. Eleven positive samples were homozygous for a novel mutation c.87 + 1G > A, that abolishes an intron 2 donor splice site and most likely causes skipping of exon 2. The prevalence of AKU observed earlier seems to be highly increased in people of nomadic origin. 相似文献