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131.
132.
OBJECTIVES: Hepatic ultrasound (US) is readily available and physicians usually trust the results of an US report suggesting fatty liver, but there are conflicting reports on its accuracy, especially in patients with chronic liver disease (CLD). Therefore, we retrospectively examined liver biopsies in patients with CLD and compared the histologic results to the hepatic US findings. METHODS: Liver biopsies were graded for fat (grades 0 to 3), inflammation (grades 0 to 4), and fibrosis (stages 0 to 4) in 131 patients with CLD (89% had chronic hepatitis C). Hepatic US interpretations were grouped into 3 categories-"normal," "fatty liver," and "nonspecific." A secondary analysis was performed using 3 sonographic categories based on the echogenicity: normal, "increased echogenicity," and "heterogenous." The US results were then compared with the liver biopsy results. RESULTS: A normal US report was associated with many false negatives, as 25% of these patients had fat (grades 1 to 3) on biopsy; furthermore, 46% had "significant fibrosis" (stages 2 to 4) or "significant inflammation" (grades 2 to 4). A "fatty liver" interpretation correctly identified fat on biopsy in 36.4% and "significant fat" (grades 2 to 3) in 11.4%, but 66% had significant fibrosis or significant inflammation. An US with increased echogenicity correctly identified fat in 43.5% and significant fat in 19.4%, but 69.4% had significant fibrosis or significant inflammation. The sensitivity of an US ranged from 11.4% to 88.2% and the specificity ranged from 40.4% to 86.2%, depending on the degree of steatosis on biopsy and the sonographic interpretation being considered. CONCLUSIONS: US is inaccurate for diagnosing hepatic steatosis in patients with CLD. Echogenic abnormalities are more likely to be the result of fibrosis or inflammation in this setting.  相似文献   
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Chronic granulomatous disease (CGD) is a rare congenital disorder characterized by repeated bacterial and fungal infections. Aside from a high incidence of liver abscess, little is known about hepatic involvement in CGD. The aim of this study was to describe the spectrum of liver abnormalities seen in CGD. The charts of 194 patients with CGD followed at the NIH were reviewed, with a focus on liver abnormalities. Liver enzyme elevations occurred on at least one occasion in 73% of patients during a mean of 8.9 years of follow-up. ALT elevations were generally transient. Although transient alkaline phosphatase (ALP) elevations were also common, persistent ALP elevations lasting up to 17.6 years were seen in 25% of patients. Liver abscess occurred in 35% of patients. Drug-induced hepatotoxicity was documented in 15% of patients but likely occurred more frequently. Hepatomegaly was found in 34% and splenomegaly in 56% of patients. Liver histology showed granulomata in 75% and lobular hepatitis in 90% of specimens. Venopathy of the portal vein was common (80%) and associated with splenomegaly. Venopathy of the central vein was also common (63%) and was associated with the number of abscess episodes. Nodular regenerative hyperplasia (NRH) was seen in 9 patients, including 6 of 12 autopsy specimens. CONCLUSION: Liver enzyme abnormalities occur frequently in patients with CGD. In addition to liver abscesses and granulomata, drug hepatotoxicity is likely underappreciated. Vascular lesions such as venopathy and--to a lesser extent--NRH are common. The cause and clinical consequences of venopathy await prospective evaluation.  相似文献   
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OBJECTIVE: To determine the diagnostic performance of multidetector computed tomography (MDCT) for the detection of left atrial appendage (LAA) thrombus as compared with transesophageal echocardiography. METHODS: Multidetector computed tomography was evaluated in 43 patients qualitatively for the presence or absence of a filling defect in the LAA and compared with transesophageal echocardiography. Additionally, a ratio of the mean computed tomographic attenuation in the LAA apex to the mean computed tomographic attenuation in the aortic root was used for quantitative evaluation. RESULTS: A filling defect visualized in the LAA by MDCT corresponded to a sensitivity of 70% (7/10), a specificity of 82% (27/33), and a negative predictive value of 90% (27/30) for detection of LAA thrombus. When using quantitative parameters, MDCT demonstrated a sensitivity of 80% (8/10), a specificity of 73% (24/33), and a negative predictive value of 92% (24/26). Multidetector computed tomography was not able to differentiate LAA thrombus from spontaneous echo contrast by either visual evaluation or by quantitative parameters. CONCLUSIONS: Multidetector computed tomography remains limited for the detection of LAA thrombus. However, a subgroup of patients at very high risk for LAA thrombus may benefit from the high negative predictive value of cardiac MDCT.  相似文献   
138.
BACKGROUND: Mucinous, medullary, and tubular carcinomas are uncommon types of breast cancer whose rarity does not permit large single-institution studies or randomized trials to define optimal treatments. In this study, we evaluated the long-term outcomes of breast-conserving therapy (BCT) for these subtypes of breast cancer and compared them with those for invasive ductal carcinoma. METHODS: In our institutional database of patients who received BCT from 1965 to 1999, 1,643 patients with stage I to II mucinous (61), medullary (37), tubular (60), and invasive ductal (1,485) histologies were identified. The clinical and pathologic features of the 4 groups were evaluated and compared with respect to local-regional recurrence rates, disease-free survival, and overall survival (OS). RESULTS: No statistically significant differences were found in the local-regional failure rate among the 4 groups (10.6-year median follow-up). Only patients with tubular carcinoma had better 5- and 10-year OS rates (P = .013). In multivariable analysis, factors associated with improved OS included age at or below 50 years, negative nodal status, use of chemotherapy or hormonal therapy, and tubular histology. CONCLUSIONS: BCT for mucinous, medullary, or tubular carcinoma resulted in similar local-regional failure rates to that for invasive ductal carcinoma. Tubular carcinoma patients had the most favorable OS. BCT is an appropriate treatment strategy for early-stage mucinous, medullary, and tubular carcinomas.  相似文献   
139.

Ethnopharmacological relevance

Zingiber zerumbet (L.) Smith, a wild edible ginger species or locally known as “lempoyang”, commonly used in the Malays traditional medicine as an appetizer or to treat stomachache, toothache, muscle sprain and as a cure for swelling sores and cuts.

Aim

The present study was conducted to investigate the possible mechanism of actions underlying the systemic antinociception activity of the essential oil of Zingiber zerumbet (EOZZ) in chemical-induced nociception tests in mice.

Materials and methods

Acetic acid-induced abdominal constriction, capsaicin-, glutamate- and phorbol 12-myristate 13-acetate-induced paw licking tests in mice were employed in the study. In all experiments, EOZZ was administered systemically at the doses of 50, 100, 200 and 300 mg/kg.

Results

It was shown that EOZZ given to mice via intraperitoneal and oral routes at 50, 100, 200 and 300 mg/kg produced significant dose dependent antinociception when assessed using acetic acid-induced abdominal writing test with calculated mean ID50 values of 88.84 mg/kg (80.88-97.57 mg/kg) and 118.8 mg/kg (102.5-137.8 mg/kg), respectively. Likewise, intraperitoneal administration of EOZZ at similar doses produced significant dose dependent inhibition of neurogenic pain induced by intraplantar injection of capsaicin (1.6 μg/paw), glutamate (10 μmol/paw) and phorbol 12-myristate 13-acetate (1.6 μg/paw) with calculated mean ID50 of 128.8 mg/kg (118.6-139.9 mg/kg), 124.8 mg/kg (111.4-139.7 mg/kg) and 40.29 (35.39-45.86) mg/kg, respectively. It was also demonstrated that pretreatment with l-arginine (100 mg/kg, i.p.), a nitric oxide precursor significantly reversed antinociception produced by EOZZ suggesting the involvement of l-arginine/nitric oxide pathway. In addition, methylene blue (20 mg/kg, i.p.) significantly enhanced antinociception produced by EOZZ. Administration of glibenclamide (10 mg/kg, i.p.), an ATP-sensitive K+ channel antagonist significantly reversed antinociceptive activity induced by EOZZ.

Conclusion

Together, the present results suggested that EOZZ-induced antinociceptive activity was possibly related to its ability to inhibit glutamatergic system, TRPV1 receptors as well as through activation of l-arginine/nitric oxide/cGMP/protein kinase C/ATP-sensitive K+ channel pathway.  相似文献   
140.
The aim of this study was to report on the clinical and monetary productivity of fourth-year dental students at community-based clinical sites and school-based clinics at the Harvard School of Dental Medicine (HSDM). This study included forty-seven students from the graduating classes of 2006, 2007, and 2008. These fourth-year students were required to spend twelve weeks at one of several participating community health centers throughout Massachusetts and New Hampshire. Students also treated their patient pool in the teaching practice at HSDM in the fourth year. The most common sixty American Dental Association procedure codes were compared, and variables were created by grouping them by specialty or type of service. HSDM dental students completed 8,365 procedures at an externship site during their community experience. An average of 178 procedures was completed per student, and mean revenue of $17,486 was produced. In comparison, the same students completed 3,640 procedures during an equal amount of time spent (normalized for this study) at the school teaching practice clinic, where each student completed an average of seventy-seven procedures and generated $16,802 in revenue. The results of this study show that fourth-year dental students at the community health centers, working under the supervision of adjunct faculty, completed more than double the number of procedures they did in the HSDM teaching practice clinic. However, the revenue generated was very similar at the two sites. In addition, the types of procedures performed by students at externship sites were simpler than the complex and specialized procedures performed at the HSDM clinic, which include fixed and removable prosthetics, periodontal surgery, and implantology.  相似文献   
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