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71.
Dental plaque is considered to be a major etiological factor in the development of periodontal disease. Accordingly, the elimination of supra- and sub-gingival plaque and calculus is the cornerstone of periodontal therapy. Dental calculus is mineralized plaque; because it is porous, it can absorb various toxic products that can damage the periodontal tissues. Hence, calculus should be accurately detected and thoroughly removed for adequate periodontal therapy. Many techniques have been used to identify and remove calculus deposits present on the root surface. The purpose of this review was to compile the various methods and their advantages for the detection and removal of calculus.  相似文献   
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73.
Angiosarcoma is a rare, highly malignant tumor arising from endothelial cells of small blood vessels. They usually occur in the skin, deep soft tissues, breast and liver. Pleural angiosarcomas are extremely rare and are restricted to case reports in medical literature. It is very difficult to distinguish them from malignant mesotheliomas on clinical, radiological and even histopathological features. Immunohistochemistry is valuable in making the diagnosis, showing negative reactivity for mesothelial markers and positivity for vascular markers. Prognosis is generally dismal except in occasional cases where the disease is localized and amenable for surgical resection. We report a 55-year-old man who presented to us with chest pain, cough and hemoptysis and was diagnosed to have a pleural angiosarcoma.  相似文献   
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Morphometric assessments, such as muscle density and body fat distribution, have emerged as strong predictors of cardiovascular risk and postoperative morbidity and mortality. To date, no study has examined morphometric mortality risk prediction among kidney transplant (KT) candidates. KT candidates, waitlisted 2008‐2009, were identified (n=96) and followed to the earliest of transplant, death, or administrative end of study. Morphometric measures, including abdominal adipose tissue, paraspinous and psoas muscle composition, and aortic calcification, were measured from CTs. Risk of waitlist mortality was examined using Cox proportional hazard regression. On adjusted analyses, radiologic measures remained independently and significantly associated with lower waitlist mortality; the addition of radiologic measures significantly improved model predictive ability over models containing traditional risk factors alone (net reclassification index: 0.56, 95% CI: 0.31‐0.75). Higher psoas muscle attenuation (indicative of leaner muscle) was associated with decreased risk of death (aHR: 0.93, 95% CI: 0.91‐0.96, P<.001), and for each unit increase in lean paraspinous volume, there was an associated 2% decreased risk for death (aHR: 0.98, 95% CI: 0.96‐0.99, P=.03). Radiologic measures of lean muscle mass, such as psoas muscle attenuation and paraspinous lean volume, may improve waitlist mortality risk prediction and candidate selection.  相似文献   
76.
Splanchnic glucose uptake (SGU) plays a major role in the disposal of an oral glucose load (OGL). To investigate the effect of an elevated plasma free fatty acid (FFA) concentration on SGU in patients with type 2 diabetes, we measured SGU in eight diabetic patients (mean age 51 +/- 4 years, BMI 29.3 +/- 1.4 kg/m(2), fasting plasma glucose 9.3 +/- 0.7 mmol/l) during an intravenous Intralipid/heparin infusion and 7-10 days later during a saline infusion. SGU was estimated by the OGL insulin clamp method: subjects received a 7-h euglycemic-hyperinsulinemic clamp (insulin infusion rate = 100 mU x m(-2) x min(-1)), and a 75-g OGL was ingested 3 h after starting the insulin clamp. After glucose ingestion, the steady-state glucose infusion rate during the insulin clamp was decreased appropriately to maintain euglycemia. SGU was calculated by subtracting the integrated decrease in glucose infusion rate during the 4-h period after glucose ingestion from the ingested glucose load (75 g). 3-[(3)H]glucose was infused during the 3-h insulin clamp before glucose ingestion to determine the rates of endogenous glucose production and glucose disappearance (R(d)). Intralipid/heparin or saline infusion was initiated 2 h before the start of the OGL clamp. Plasma FFA concentrations were significantly higher during the OGL clamp with the intralipid/heparin infusion than with the saline infusion (2.5 +/- 0.3 vs. 0.11 +/- 0.02 mmol/l, P < 0.001). During the 3-h insulin clamp period before glucose ingestion, Intralipid/heparin infusion reduced R(d) (4.4 +/- 0.3 vs. 5.3 +/- 0.3 mg x kg(-1) x min(-1), P < 0.01). During the 4-h period after glucose ingestion, SGU was significantly decreased during the intralipid/heparin versus saline infusion (30 +/- 2 vs. 37 +/- 2%, P < 0.01). In conclusion, an elevation in plasma FFA concentration impairs both peripheral and SGU in patients with type 2 diabetes.  相似文献   
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78.
Recent studies suggest that salt split skin is a more sensitive substrate than intact skin for immunofluorescence diagnosis of bullous pemphigoid. We undertook this study to define the role of salt split technique of immunofluorescence findings in 32 clinical and histopathology confirmed cases of bullous pemphigoid. Both direct and indirect immunofluorescences were performed using normal and split skin. Direct immunofluorescence positivity of 100% was noted with both routine and salt split method. Additional immunoreactant deposition was noted with direct method on split skin in 5 cases. Patterns of fluorescence in the latter were roof (40.60%), floor (9.4%) and combined roof and floor (50%). On indirect immunofluorescence, positivity was almost doubled with salt split technique ( 68%) as compared to routine method (36%). Thus, salt split technique was equivalent to routine on direct method in positivity with additional immunoreactant deposits noted in some and had double the sensitivity of the indirect method in detecting immunofluorescence in bullous pemphigoid.  相似文献   
79.
Biliary tract strictures and leaks are the second most common complications following orthotopic liver transplantation. Nonanastomotic bile duct complications are most often caused by hepatic artery thrombosis and can result in fulminant hepatic necrosis, bile duct strictures, and bile duct leaks that increase the risk of cholangitis, sepsis, and abscess. The emergency physician and radiologist should strongly suspect biliary disease in a post-transplant patient presenting with elevated liver function tests, jaundice, fever, and/or abdominal pain in order to achieve diagnosis and treatment rapidly. We present the case of a liver transplant patient who developed bile duct necrosis and hepatic infarction secondary to hepatic artery thrombosis 5 months after surgery. In addition, we discuss a new contrast-enhanced MR cholangiographic technique that has the potential to be performed in the emergency setting as the only diagnostic test prior to appropriate therapy. Electronic Publication  相似文献   
80.
Gallstone ileus is a rare complication of recurrent gallstone cholecystitis and usually occurs in elderly female patients. Recurrent gallstone ileus occurs in 5% of patients with a previous episode of gallstone ileus and is associated with a mortality of 20%. We present a 52-year-old female with recurrent gallstone ileus 1 year after her initial episode. Electronic Publication  相似文献   
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