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91.
Kishore Maganty David Levi Jang Moon Pablo A. Bejarano Leopoldo Arosemena Andreas Tzakis Paul Martin 《Digestive diseases and sciences》2010,55(12):3597-3601
Background
Combined hepatocellular carcinoma and intrahepatic cholangiocarcinoma is a rare hepatobiliary malignancy incorporating components derived from both hepatocyte and intrahepatic bile duct epithelium. The natural history, treatment, and prognosis of this distinct cancer differ from hepatocellular carcinoma (HCC) or cholangiocarcinoma (CC) and are not completely understood. There is considerable controversy about the classification, treatment, and survival, which in turn is related to the rarity of the condition. Treatment options include surgical resection and the prognosis is believed to be better than CC but worse than HCC alone. 相似文献92.
Manpreet S. Salooja Manender Singla Anupam Srivastava Kishore C. Mukherjee 《Journal of the Saudi Heart Association》2013,25(2):95-97
Blunt traumatic cardiac rupture is associated with a high mortality rate. Motor vehicle accidents account for most cardiac ruptures, but crush injury is relatively rare. We describe a case of a 72-year-old man who had the left atrial appendage ruptured through blunt trauma due to a fall from scooter. Simple suture repair of the atrial appendage was achieved after clamping the base of the left atrium to control the bleeding. He recovered without complication. Traumatic injury to left atrial appendage is rarely seen and reported. 相似文献
93.
Unexpected nondenitrifier nitrous oxide reductase gene diversity and abundance in soils 总被引:5,自引:0,他引:5
Robert A. Sanford Darlene D. Wagner Qingzhong Wu Joanne C. Chee-Sanford Sara H. Thomas Claribel Cruz-García Gina Rodríguez Arturo Massol-Deyá Kishore K. Krishnani Kirsti M. Ritalahti Silke Nissen Konstantinos T. Konstantinidis Frank E. L?ffler 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(48):19709-19714
Agricultural and industrial practices more than doubled the intrinsic rate of terrestrial N fixation over the past century with drastic consequences, including increased atmospheric nitrous oxide (N2O) concentrations. N2O is a potent greenhouse gas and contributor to ozone layer destruction, and its release from fixed N is almost entirely controlled by microbial activities. Mitigation of N2O emissions to the atmosphere has been attributed exclusively to denitrifiers possessing NosZ, the enzyme system catalyzing N2O to N2 reduction. We demonstrate that diverse microbial taxa possess divergent nos clusters with genes that are related yet evolutionarily distinct from the typical nos genes of denitirifers. nos clusters with atypical nosZ occur in Bacteria and Archaea that denitrify (44% of genomes), do not possess other denitrification genes (56%), or perform dissimilatory nitrate reduction to ammonium (DNRA; (31%). Experiments with the DNRA soil bacterium Anaeromyxobacter dehalogenans demonstrated that the atypical NosZ is an effective N2O reductase, and PCR-based surveys suggested that atypical nosZ are abundant in terrestrial environments. Bioinformatic analyses revealed that atypical nos clusters possess distinctive regulatory and functional components (e.g., Sec vs. Tat secretion pathway in typical nos), and that previous nosZ-targeted PCR primers do not capture the atypical nosZ diversity. Collectively, our results suggest that nondenitrifying populations with a broad range of metabolisms and habitats are potentially significant contributors to N2O consumption. Apparently, a large, previously unrecognized group of environmental nosZ has not been accounted for, and characterizing their contributions to N2O consumption will advance understanding of the ecological controls on N2O emissions and lead to refined greenhouse gas flux models. 相似文献
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96.
KB Thomas AH Sutor N Altinkaya A Grohmann A Zehenter JU Leititis 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(6):697-700
ABSTRACT. von Willebrand factor (vWF) antigen (vWF:Ag) and vWF-collagen binding activity (vWF:CBA) were measured in plasma by parallel quantitative ELISAs in normal newborns and infants ( n =71). The medians for vWF:Ag (IUjml) and vWF:CBA (Ujml), respectively, were 1.46 and 1.91 for 2-7 day-old (n = 43), 1.22 and 1.40 for 2-4 week-old (n = 14), 1.22 and 1.15 for 2-6-month-old (n = 14) infants and 0.98 and 1.08 (n = 36) in normal adults. Elevated levels of vWF:Ag, but particularly vWF:CBA were seen for up to 4 weeks of life reaching adult levels between 2 and 6 months of life. The elevated levels of the vWF parameters indicate that caution should be exercised when interpreting laboratory data and diagnosing von Willebrand disease in newborns and young infants and warrant the use of age-specific reference ranges. The efficient haemostasis observed during early neonatal life may in part be due to the increased ability of vWF to interact with collagen. 相似文献
97.
Sudarsan De Rajendra Kumar Tanwar Ram Murti Kamble Vinod Raina Subirendra Kumar Goura Kishore Rath 《Indian journal of otolaryngology and head and neck surgery》1996,48(1):41-44
Primary lymphoma is the most common nonepithelial malignant tumour arising from the paranasal sinus region. It occurs mostly in middle aged and elderly patients with a nonspecific clinical profile resembling that of commoner epithelial sinonasal malignancies. Modified Rappaport’s and the Working Formulation are the frequently used histopathological classification systems. Radiation therapy is the mainstay of treatment with excellent local control of the disease. Most of the failures occur at distant sites outside the treatment area or in the form of disseminateed disease. Chemotherapy, though used in limited number of patients in some series, seems to have a better role to play in the management of these tumours in future as most of the sinonasal lymphomas are of poorly differentiated variety or of unfavourable histology. 相似文献
98.
Harjai KJ Samal A Shah M Edupuganti R Nunez E Pandian NG 《Echocardiography (Mount Kisco, N.Y.)》2002,19(8):641-644
Left ventricular geometry is suspected to affect heterogeneity of myocardial repolarization; therefore, it is plausible but unproven that increased sphericity of the left ventricle is associated with greater QT interval dispersion. In 60 patients with dilated cardiomyopathy with left ventricular ejection fraction < or = 30%, we found that spherical distortion of the left ventricle was associated with increased QT dispersion, implying increased heterogeneity of myocardial repolarization. 相似文献
99.
Jain AK Kaplan RA Gadde KM Wadden TA Allison DB Brewer ER Leadbetter RA Richard N Haight B Jamerson BD Buaron KS Metz A 《Obesity research》2002,10(10):1049-1056
OBJECTIVE: This randomized, double-blind, placebo-controlled study evaluated the efficacy and tolerability of bupropion sustained-release (bupropion SR) in reducing weight and depressive symptoms in obese adults. RESEARCH METHODS AND PROCEDURES: Obese adults (body mass index, 30 to 44 kg/m(2)) not currently meeting criteria for major depression but with depressive symptoms (Beck Depression Inventory score 10-30) received bupropion SR 300 mg/d or placebo for 26 weeks with a 500 kcal/d-deficit diet. Patients who lost <5% of baseline weight at week 12 had bupropion SR dosage or placebo increased to 400 mg/d in a blinded fashion. RESULTS: The bupropion SR group (n = 193) lost an average of 4.4 kg (4.6% of baseline weight) vs. 1.7 kg (1.8% of baseline weight) on placebo (n = 191, p < 0.001, last-observation-carried-forward analysis). More patients in the bupropion SR group than in the placebo group (40% vs. 16% of intent-to-treat sample, 50% vs. 28% of completers, respectively) lost at least 5% of baseline weight (p < 0.05 at week 4, p < 0.001 at weeks 6 to 26). The percentage of patients reporting > or =50% decrease in depressive symptoms did not differ between groups, but depressive symptoms improved more with bupropion SR than with placebo among patients with a history of major depression (p < 0.05, weeks 4 to 26). In the sample as a whole, improvement in depressive symptoms was related to weight loss of > or =5% regardless of treatment (p < 0.0001). Bupropion SR was well-tolerated. DISCUSSION: Bupropion SR in combination with a 500 kcal/d-deficit diet facilitated weight loss. Weight loss of > or =5% may improve mood in obese patients with depressive symptoms. 相似文献
100.
MR findings in intralabyrinthine schwannomas 总被引:2,自引:0,他引:2
AIM: Intralabyrinthine schwannomas (ILS) are rare benign tumours. They are not always recognized on routine magnetic resonance imaging (MRI). We aimed to study the clinical presentation and MRI findings in our patients with ILS. MATERIALS AND METHODS: Retrospective analysis of patients with vestibular schwannomas treated at this center. RESULTS: Of 144 vestibular schwannomas studied at this centre, three patients had an ILS. The most common presenting symptoms were unilateral hearing loss, tinnitus and vertigo. Two patients demonstrated a progressive sensorineural hearing loss (SNHL). The third patient had a severe SNHL at presentation. MRI enhanced with contrast medium was positive in the two patients with progressive SNHL and negative in the patient with the severe SNHL. CONCLUSION: This series demonstrates the ability of MRI to identify schwannomas filling the labyrinth, and also its inability to identify extremely small ILS. It underlines the importance of sending the cristae of patients undergoing labyrinthectomy for presumed Ménière's disease for histological examination. 相似文献