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991.
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Journal of Gastroenterology - Predictive factors for intrahepatic cholangiocarcinoma in long-term follow-up of hepatolithiasis are unknown. We thus conducted a cohort study to investigate the...  相似文献   
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As an intrathoracic goiter expands, it causes airway stenosis and phrenic nerve paralysis, and slight respiratory stimuli can trigger sudden life-threatening hypoventilation. A 78-year-old obese woman with a large intrathoracic goiter was found unconscious with agonal breathing in her room early in the morning. Cardiopulmonary resuscitation restored spontaneous circulation. She underwent surgical removal of the goiter; however, she required long-term mechanical ventilation because of atelectasis due to phrenic nerve paralysis. In patients with large intrathoracic goiters, difficulty breathing on exertion and diaphragm elevation on chest X-ray may be significant findings predicting future respiratory failure.  相似文献   
995.
This review aimed to highlight the etiology, diagnosis, treatment, and prevention of obstructive and secretory complications associated with diverting ileostomy (DI). Obstructive complications at the stoma site are termed stoma outlet obstruction (SOO) or stoma-related obstruction (SRO). The incidence of SOO/SRO is 5.4%-27.3%, and the risk factors are multifactorial; however, the configuration of the stoma limb and the thickness of the rectus abdominis muscle (RAM) may be of particular concern. Trans-stomal tube decompression is initially attempted with a success rate of 33%-86%. A thick RAM may carry the risk of recurrence. Surgical refinement, including a wider incision of the anterior sheath and adequate stoma limb length, avoids tension and immobility and may decrease SOO/SRO. Secretory complications of DI are termed high output stoma (HOS). Persistent HOS lead to water and sodium depletion, and secondary hyperaldosteronism, resulting in electrolyte imbalances, such as hypomagnesemia. The incidence of HOS is 14%-24%, with an output of 1000-2000 mL/d lasting up to three days. Treatment of HOS is commenced after excluding postoperative complications or enteritis and includes fluid intake restriction, antimotility and antisecretory drug therapies, and magnesium supplementation. Intensive monitoring and surveillance programs have been successful in decreasing readmissions for dehydration.  相似文献   
996.
In a rotary motor F(o)F(1)-ATP synthase that couples H(+) transport with ATP synthesis/hydrolysis, it is thought that an F(o)c subunit oligomer ring (c-ring) in the membrane rotates as protons pass through F(o) and a 120 degrees rotation produces one ATP at F(1). Despite several structural studies, the copy number of F(o)c subunits in the c-ring has not been determined for any functional F(o)F(1). Here, we have generated and isolated thermophilic Bacillus F(o)F(1), each containing genetically fused 2-mer-14-mer c (c(2)-c(14)). Among them, F(o)F(1) containing c(2), c(5), or c(10) showed ATP-synthesis and other activities. When F(1) was removed, F(o) containing c(10) worked as an H(+) channel but F(o)s containing c(9), c(11) or c(12) did not. Thus, the c-ring of functional F(o)F(1) of this organism is a decamer. The inevitable consequence of this finding is noninteger ratios of rotation step sizes of F(1)/F(o) (120 degrees /36 degrees ) and of H(+)/ATP (10:3). This step-mismatch necessitates elastic twisting of the rotor shaft (and/or the side stalk) during rotation and permissive coupling between unit rotations by H(+) transport at F(o) and elementary events in catalysis at F(1).  相似文献   
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BACKGROUND: To investigate the activation patterns and conduction velocity (CV) in the posterolateral right atrial (RA) wall during typical counterclockwise atrial flutter (AFL) using an electroanatomic mapping system. METHODS AND RESULTS: During typical AFL in 25 patients, the transverse conduction pattern and CV were classified and calculated. The line blocking transverse conduction was defined by the conduction pattern and double potentials recorded during mapping. There were 3 types (including 2 subtypes) of transverse conduction pattern based on the conduction blocks across the posterolateral RA in a line between the superior and inferior venae cava. Trans-cristal conduction activation in a horizontal direction was seen in all but 4 patients. The CV in the gap area was 0.59+/-0.21 m/s. CONCLUSIONS: Three types of transverse conduction pattern were observed during trans-ctristal conduction and the trans-ctristal CV was relatively slower than that in other parts of the RA, except for the isthmus.  相似文献   
1000.
The effects of L-carnitine (900 mg, p.o. daily) on exercise performance were studied in 12 patients with stable effort angina using a multistage treadmill exercise test. Exercise tests were performed at the end of the placebo period and after 4 and 12 weeks of carnitine therapy. While 12 patients experienced angina during treadmill tests in the placebo period, 2 patients were free of angina after treatment with carnitine. The mean exercise time was 11.4 +/- 0.7 min (mean +/- SE) in the placebo period. This increased significantly to 12.2 +/- 0.5 min (p less than 0.05) after 4 weeks and 12.8 +/- 0.5 min (p less than 0.01) after 12 weeks of treatment with carnitine. The time required for 1 mm ST depression to occur was 6.4 +/- 0.9 min in the placebo period. This increased significantly to 7.6 +/- 0.9 min (p less than 0.01) after 4 weeks and 8.8 +/- 1.0 min after 12 weeks of treatment with carnitine. There was significantly less ST segment depression during the same exercise load after 12 weeks of treatment as compared with that in the placebo period (p less than 0.05). The heart rate and the pressure rate product at the same work load showed no significant difference among the 3 testing periods. The results of this study suggest that L-carnitine may improve exercise tolerance in patients with effort angina.  相似文献   
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