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61.
Background: During laparoscopic cholecystectomy (LC), venous stasis of the legs may occur which cannot be prevented by a graded compression bandage used for a standard laparotomy. In this study, we investigated whether femoral vein stasis during LC could be prevented using an intermittent sequential pneumatic compression device (IPC). Methods: The effects of an IPC on blood flow in the legs prior to pneumoperitoneum (baseline), at pneumoperitoneum, at postural change and at deflation were examined by color Doppler ultrasonography on each of two groups, namely the patients without an IPC on the lower extremities (group 1, n = 20) and the patients with an IPC (group 2, n = 20). Results: The peak femoral vein velocity in group 1 at a pneumoperitoneum pressure of 10 mmHg in the reverse Trendelenburg's position was significantly decreased to 29.3 ± 3.4% of the baseline value (P < 0.05). However, in group 2, the velocity was maintained and there was no significant decrease. The blood flow velocity when the IPC was used significantly differed from that when the IPC was not used (P < 0.01). The area of the femoral vein in group 1 at a pneumoperitoneum pressure of 10 mmHg in the reverse Trendelenburg's position significantly increased to 379.5 ± 16.3% of the baseline value (P < 0.05). In group 2, it significantly increased to 387.0 ± 19.1% (P < 0.05). However, the area of the femoral vein when the IPC was used did not significantly differ from that when the IPC was not used. Conclusion: The use of an IPC maintained the peak femoral vein velocity even under pneumoperitoneum and in the reverse Trendelenburg's position.  相似文献   
62.
Three adults, 2 with tricuspid aortic valve and 1 with bicuspid valve, underwent valvuloplasty for aortic valve regurgitation resulting from cusp prolapse. Surgical procedures consisted of combined cusp plication by triangular cusp resection and subcommissural annuloplasty. Doppler echocardiography revealed trivial aortic valve regurgitation intraoperatively and less than I/IV at discharge in all cases. After mean follow-up of 15 months, 2 tricuspid aortic valve patients remain I/IV regurgitation and II/IV in the bicuspid patient. Although long-term results remain unclear, our results show that this procedure is feasible and beneficial in patients with aortic valve regurgitation due to cusp prolapse.  相似文献   
63.
64.
Portal gas is relatively rare, and the majority of reported cases have shown it to have a close relation to bowel diseases. At present, portal exploration usually begins with color Doppler sonography, and clinicians now possess a good understanding of color Doppler findings of a wide spectrum of portal abnormalities. However, the color Doppler sign we present in this article has not been reported before. We report two cases of ischemic bowel disease in which B-mode ultrasound showed multiple hyperechoic spots moving in the portal vein; the color Doppler appearance was as if the portal vein was on fire (flaming portal vein sign). Knowledge of this simple color Doppler sign helps to improve the diagnostic strategies in patients with portal gas.  相似文献   
65.
OBJECTIVE: Recent transcranial magnetic stimulation (TMS) studies showed that the sensory input can decrease the motor cortex excitability (afferent inhibition). To clarify the effect of attention on sensorimotor integration, we investigated the effect of spatial attention on afferent inhibition. METHODS: Right median nerve electrical stimulation followed, at variable delays (10-300 ms), by TMS over the left motor cortex was applied to 9 subjects, during 3 conditions; spatial attention to the right and left hand, and control (no attention) tasks. RESULTS: Inhibition of the motor evoked potential occurred at inter-stimulus interval of 20 and 100 ms, which was more was marked during spatial attention to the right than to the left hand. CONCLUSIONS: Enhancement of the afferent inhibition induced by spatial attention to the stimulated side is likely to reflect the interaction between attention and sensorimotor integration. SIGNIFICANCE: The spatial attention may modulate the sensorimotor integration studied by afferent inhibition of the MEP.  相似文献   
66.
Eleven patients with spinal cord compression due to metastatic epidural tumors were analyzed. Primary tumors were Hodgkin's disease, non-Hodgkin's lymphoma, multiple myeloma (two patients each), cervical cancer, malignant melanoma, gastric cancer, lung cancer, and neuroblastoma (one patient each). It was felt that myelography is the most important diagnostic test, although CT scan and bone scan may give further diagnostic information in some patients. Six patients were treated with decompressive laminectomy and postoperative radiotherapy, and five with radiotherapy alone. Regardless of the pretreatment neurological status and the type of treatment given, the functional prognosis in our small series of patients appeared to be favorable for radiosensitive tumors such as malignant lymphoma and multiple myeloma.  相似文献   
67.
5'-DFUR was administered orally at 800 mg/day, for total dosage of 57.6 g to the gastric cancer patient, classified Borrmann Type 2, with Virchow's node metastasis. Gastric tumor had diminished in size on the fluoroscopy and the endoscopy. We then made distal gastrectomy. The resected stomach showed moderately differentiated tubular adenocarcinoma on the pathological examination. Side effect was diarrhea.  相似文献   
68.
A human parotid gland adenocarcinoma cell line, with an intercalated duct cell phenotype of the salivary gland and expression of vasoactive intestinal polypeptide and amylase, was cultivated in the presence of dibutyryl cyclic adenosine 3',5'-monophosphate (dB-cAMP). Morphological changes occurred; cells formed long cytoplasmic processes densely packed with ample microfibrils, as well as microtubules, and grew in a netlike appearance. In addition, it has been found by the immunofluorescence staining technique, immunoblotting, or immunoelectron microscopy that the cells treated with dB-cAMP express neurofilaments, neuron-specific enolase, synaptophysin, and HNK-1 antigen, as well as the alpha- and beta-chains of tubulin, whereas these antigens are not detected in untreated cells. The expression of vasoactive intestinal polypeptide detected diffusely in the cytoplasm of untreated cells was restricted to the cell membranes during the cultivation of cells in the presence of dB-cAMP, while expression of amylase persisted in the treated cells in a fashion similar to that in untreated cells. Moreover, both anchorage-independent and anchorage-dependent growth of the cells was markedly suppressed in the presence of dB-cAMP. After removal of dB-cAMP from the culture, the treated cells returned rapidly to the phenotype and growth rate of the untreated cells. These findings indicate that reversible conversion into cells with phenotypic features of neuronal cells of a human parotid adenocarcinoma cell line occurs in growth medium containing dB-cAMP.  相似文献   
69.
OBJECTIVE: To determine whether the combination of the phosphodiesterase 5 inhibitor zaprinast and inhaled nitric oxide (NO) decreases hypoxic pulmonary hypertension in the rat. DESIGN: Prospective, experimental study. SETTING: Animal laboratory of a university medical center. SUBJECTS: Male Sprague-Dawley rats. INTERVENTIONS: Anesthetized rats were mechanically ventilated and instrumented for measurement of mean systemic arterial pressure, pulmonary arterial pressure, and cardiac output. In group 1, four acute hypoxic challenges (FIO2 = 0.17 for 5 mins) were performed: initial, during 40 ppm inhaled NO, immediately after discontinuation of 5 mins of inhaled NO, and final. In group 2 rats, an initial hypoxic challenge was performed and rats then received zaprinast (3 mg/kg bolus followed by 0.3 mg/kg/min infusion). Four hypoxic challenges analogous to group 1 were then performed during zaprinast administration. MEASUREMENTS AND MAIN RESULTS: Initial hypoxic challenge produced similar increases in pulmonary arterial pressure in both groups. In group 1, inhaled NO either only before or only during hypoxia decreased the pulmonary hypertensive response to hypoxia. In group 2, zaprinast administration did not alter hemodynamics. Zaprinast alone decreased the pulmonary hypertensive response to hypoxia. The combination of zaprinast and inhaled NO (either before or during hypoxia) abolished the pulmonary hypertensive response to hypoxia. CONCLUSIONS: Treatment with inhaled NO for 5 mins before but not during hypoxia is as effective as inhaled NO during hypoxia. Inhaled NO and zaprinast both decrease the pulmonary hypertensive response to hypoxia, and the combination abolishes the response. The combination of a phosphodiesterase 5 inhibitor and inhaled NO may have clinical applicability in the treatment of pulmonary hypertension.  相似文献   
70.
Trends in colonoscopy for colorectal cancer screening   总被引:5,自引:0,他引:5  
BACKGROUND: A major health priority is to increase colorectal cancer screening, and colonoscopy has become an increasingly important method of screening. The Medicare program began coverage for colonoscopy for average risk individuals in 2001. OBJECTIVES: We sought to examine whether overall colorectal cancer screening increased over time and whether these increases were a result of increased utilization of all methods or a result of greater use of colonoscopy but reduced use of other methods, whether the enactment of Medicare coverage was associated with an increase in colonoscopy among Medicare enrollees, and whether these trends equally affected subpopulations. METHODS: We used nationally representative data from the 2000 and 2003 National Health Interview Surveys and analyzed data using used chi, difference-in-differences tests, and logistic regression analyses to examine whether screening rates differed between 2000 and 2003. RESULTS: The percentage of individuals being screened for colorectal cancer using any method increased modestly from 2000 to 2003 (3%), with increases a result of increased use of colonoscopy and a reduction in the use of other methods. Increases in colonoscopy use were significant among all populations except the insured, non-Medicare population with low incomes. Among Medicare enrollees with high/middle incomes, colonoscopy use increased 14% from 2000 to 2003 compared with an increase of only 7% among low-income groups, which was a significant difference (P < 0.01). Similarly, among insured, non-Medicare enrollees with high/middle incomes, colonoscopy use increased 11% from 2000 to 2003 compared with an increase of only 4% among low-income groups, which also was a significant difference (P < 0.01). CONCLUSIONS: Colorectal cancer screening utilization increased modestly from 2000 to 2003, with the increases that primarily were the result of increased colonoscopy use. Increases in colonoscopy use, however, were primarily among high/middle income groups. Although Medicare coverage may have indirectly facilitated the increase in colonoscopy, we could not determine that coverage directly increased screening rates. Screening rates remain modest and lower income individuals continue to be screened less. Topics for future research include approaches to facilitating screening among low-income individuals and evaluating the impact of policy coverage decisions.  相似文献   
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