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21.
Performance of same-day upper and lower endoscopy has many potential advantages, as it may reduce costs, shorten hospital stay, and expedite patient care, but its feasibility, efficacy, and potential have not been carefully defined. We report here our experience with a group of 87 patients who underwent same-day upper and lower endoscopy (174 procedures) over a 2-yr period at a tertiary care VA Hospital, compared with an alternate-day upper and lower endoscopy group of 50 patients (100 procedures) over the same time period. Most patients were elderly males. Common indications for endoscopy were occult or overt gastrointestinal bleeding, previous or concomitant history of pertinent pathology (i.e., polyps, ulcers), abdominal pain, diarrhea, or other symptoms, abnormal radiological studies, and iron deficiency anemia. Both groups required similar amounts of intravenous sedation. There were no complications in either group. In both groups, common positive findings were inflammation (i.e., colitis, esophagitis), benign neoplasms, diverticulae, peptic ulcer, and cancer. In both groups, only 2-6% had negative upper and lower endoscopy, whereas either one procedure was negative in 25% and 18% of cases, respectively. We conclude that the practice of same-day inpatient upper and lower endoscopy is feasible, has excellent diagnostic yield, even in the elderly, and carries no increased risks. When indicated, the practice of same-day upper and lower endoscopy should be encouraged.  相似文献   
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The utility of MRI using magnetization transfer (MT) enhanced pulse sequences to diagnose hepatic cirrhosis in a rat model was investigated. Hepatic T1 was measured with and without MT off-resonance RF pulses in 17 treated and six control rats. The livers were evaluated histologically, and the hydroxyproline content quantitatively measured. We did not find a statistically significant linear correlation between the MR relaxation times and the degree of tissue injury. However, the MR measurements performed with MT were superior to those without differentiating the treated and control groups. Specifically, the T1 times were 695 ±76 ms for the treated group, versus 748 ± 61 ms in the controls; P= 0.095. The T1sat times were also lower in the treated group, with statistical significance: 367 ± 51 ms versus 421 ± 38 ms, P = 0.016. Finally, the change in the relaxation rates (the inverse of the relaxation times) with and without saturation were 1.31 ± 0.22 s?1 (treated group) versus 1.05 ± 0.12 s?1 (controls), which differed significantly, P= 0.001.  相似文献   
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Our recent report that fructose supported the metabolism of some, but not all axons, in the adult mouse optic nerve prompted us to investigate in detail fructose metabolism in this tissue, a typical central white matter tract, as these data imply efficient fructose metabolism in the central nervous system (CNS). In artificial cerebrospinal fluid containing 10 mmol/L glucose or 20 mmol/L fructose, the stimulus-evoked compound action potential (CAP) recorded from the optic nerve consisted of three stable peaks. Replacing 10 mmol/L glucose with 10 mmol/L fructose, however, caused delayed loss of the 1st CAP peak (the 2nd and 3rd CAP peaks were unaffected). Glycogen-derived metabolic substrate(s) temporarily sustained the 1st CAP peak in 10 mmol/L fructose, as depletion of tissue glycogen by a prior period of aglycaemia or high-frequency CAP discharge rendered fructose incapable of supporting the 1st CAP peak. Enzyme assays showed the presence of both hexokinase and fructokinase (both of which can phosphorylate fructose) in the optic nerve. In contrast, only hexokinase was expressed in cerebral cortex. Hexokinase in optic nerve had low affinity and low capacity with fructose as substrate, whereas fructokinase displayed high affinity and high capacity for fructose. These findings suggest an explanation for the curious fact that the fast conducting axons comprising the 1st peak of the CAP are not supported in 10 mmol/L fructose medium; these axons probably do not express fructokinase, a requirement for efficient fructose metabolism.  相似文献   
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Glatiramer acetate is an immunomodulating drug used in the treatment of multiple sclerosis. It consists of a copolymer of amino acid residues in the same stoichiometric proportions as in myelin basic protein. Its mechanism of action is not entirely known and is probably multifaceted, with deletion of some immune cell populations and stimulation of others in these patients. Some mechanisms involve neuroprotectant effects. There is ample evidence of its efficacy in relapsing-remitting disease, using both clinical and imaging measures of disease activity, and in this paper we review the clinical and basic studies of this drug. Finally we discuss how some of its neuroprotectant effects may be useful in neurodegeneration such as is seen in more advanced cases of multiple sclerosis and other diseases such as amyotrophic lateral sclerosis and Parkinson’s disease.  相似文献   
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The Distally Based Sural Artery Flap for Ankle and Foot Coverage   总被引:1,自引:0,他引:1  
The sural artery flap is a distally based fasciocutaneous flap that has many advantages to offer for coverage in the foot and ankle area. It has the largest arc of rotation of all the regional flaps and does not require sacrifice of any major artery, and moderate-to-large-sized defects can be covered adequately. The dissection technique is simple, and donor site morbidity is minimal. We report our experience with 17 cases. Age range was from 13 to 56 years. Ten (59%) defects were posttraumatic, 3 (17%) were related to reconstructive surgery of the foot or tendon Achilles', 2 (11%) resulted from tumor resection, and 1 each were from infection and gunshot wound. The smallest flap was 6 x 4 cm and the largest was 15 x 12 cm, with the average size being 11 x 7.5 cm. In 5 cases, the donor site was closed primarily, and in other cases, split-thickness skin graft was needed. The short saphenous vein was included in the pedicle in all cases. There was no incidence of complete flap necrosis. Follow-up ranged from 3 to 30 months. Two cases (12%) developed partial superficial necrosis. In 1 case, there was partial wound dehiscence that needed debridement and repair. Another case had postoperative discharge, which subsided after removal of the calcaneal plate. None of the patients complained of any functional problem related to loss of sensation along the lateral border of the foot. The sural island flap is a reliable, safe, and easy method of providing soft tissue coverage in the area of the foot and ankle.  相似文献   
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