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251.
A successful closure of an aneurysmal aorto-right ventricular tunnel (ARVT) in a 16-year-old male patient is reported here. An attempt at device closure had failed in this patient. Diagnosis was confirmed by Doppler echocardiography, 3-dimensional computed tomography, and cardiac catheterization. Surgical closure with a Dacron patch (W.L. Gore & Associates, Flagstaff, AZ) at the aortic end and direct closure at the ventricular end was done successfully with the patient under mild hypothermia. The postoperative echocardiogram showed a competent aortic valve with a closed ARVT.  相似文献   
252.
Significant hemodynamic alterations often occur during off-pump coronary artery bypass operations. Historically, left main coronary artery stenosis has been excluded from off-pump coronary artery bypass operations because of this concern. Many articles in recent times support off-pump operations in left main coronary artery (LMCA) stenosis. We describe here a safe and effective method to reduce the incidence of hemodynamic changes during beating heart surgery in patients with LMCA stenosis.  相似文献   
253.
OBJECTIVE: To evaluate the long-term outcome of correction of nasal valve collapse with a porous polyethylene implant. STUDY DESIGN AND SETTING: Retrospective review from November 1999 to December 2005. Nasal valve collapse was corrected with a porous polyethylene implant in 12 adults. Main outcome measures included relief of nasal obstruction and complications. Independent variables included other causes of nasal obstruction and need for revision surgery. Simple statistical analysis was performed. RESULTS: Median follow-up was 5.6 years (58 months). 75% had complete resolution of nasal obstruction. 100% had complete resolution of nasal obstruction at 6 months and had coexisting causes of nasal obstruction. The implant extrusion rate was 21%. 42% went on to have revision surgery. CONCLUSION: Correction of nasal valve collapse with a porous polyethylene implant provided good long-term symptomatic relief of nasal obstruction, but with significant incidence of infection, implant extrusion, and need for revision surgery. The use of this implant should be reserved for cases in which autogenous graft material is not available.  相似文献   
254.
Nickel exposure greatly depletes intracellular ascorbate and alters ascorbate-cholesterol metabolism. We studied the effect of the simultaneous oral treatment with L-ascorbic acid (50 mg/100 g body weight (BW) and nickel sulfate (2.0 mg/100 g BW, i.p) on nickelinduced changes in serum lipid profiles and liver histopathology. Nickel-treated rats showed a significant increase in serum low-density lipoprotein-cholesterol, total cholesterol, triglycerides, and a significant decrease in serum high-density lipoprotein-cholesterol. In the liver, nickel sulfate caused a loss of normal architecture, fatty changes, extensive vacuolization in hepatocytes, eccentric nuclei, and Kupffer cell hypertrophy. Simultaneous administration of L-ascorbic acid with nickel sulfate improved both the lipid profile and liver impairments when compared with rats receiving nickel sulfate only. The results indicate that L-ascorbic acid is beneficial in preventing nickel-induced lipid alterations and hepatocellular damage.  相似文献   
255.
256.
To determine whether Mycobacterium bovis BCG vaccination would alter gamma interferon (IFN-gamma) mRNA expression in guinea pig cells exposed to Mycobacterium tuberculosis, we cloned a cDNA encoding guinea pig IFN-gamma from a spleen cell cDNA library. The cDNA is composed of 1,110 bp, with an open reading frame encoding a 166-amino-acid protein which shows 56 and 41% amino acid sequence homology to human and mouse IFN-gamma, respectively. Spleen or lymph node cells from na?ve and BCG-vaccinated guinea pigs were stimulated with purified protein derivative (PPD) or M. tuberculosis H37Ra or H37Rv, and the total RNA was subjected to Northern blot analysis with a (32)P-labeled probe derived from the cDNA clone. Compared to the IFN-gamma mRNA expression in cells of na?ve animals, that in spleen and lymph node cells exposed to various stimuli was enhanced after BCG vaccination. However, there was a significant reduction in IFN-gamma mRNA levels when cells were stimulated with a multiplicity of infection of greater than 1 virulent M. tuberculosis bacterium per 10 cells. The enhanced IFN-gamma mRNA response in BCG-vaccinated animals was associated with an increase in the proportions of CD4(+) T cells in the spleens, as determined by fluorescence-activated cell sorter analysis. Furthermore, the nonadherent population in the spleens enriched either by panning with anti-guinea pig immunoglobulin G-coated plates or by purification on nylon wool columns produced more IFN-gamma mRNA than whole spleen cells following stimulation with concanavalin A or PPD. This indicates that T cells are principally responsible for the upregulation of IFN-gamma mRNA expression following BCG vaccination. The mechanism by which virulent mycobacteria suppress IFN-gamma mRNA accumulation is currently under investigation.  相似文献   
257.
A 29-year-old pregnant woman presented with fever, right hypochondrial pain and fatigability at 29 weeks of gestation. Dengue hemorrhagic fever was diagnosed based on clinical, hematological and serological features. However, ultrasound scanning was suggestive of acute acalculous cholecystitis. The patient was managed symptomatically and made a good recovery 8 days following onset of fever. This is the first case of acute acalculous cholecystitis coinciding with dengue hemorrhagic fever reported during pregnancy from an endemic country in Asia. The possible viral and host factors for the development of such a severe form of disease and preventive measures are discussed.  相似文献   
258.
BACKGROUND: Chlorhexidine skin cleansing might substantially reduce neonatal infection and mortality in developing countries. Few data exist on the impact of chlorhexidine cleansing on skin colonization of infants during the first day of life or on the absorption potential of chlorhexidine during newborn skin cleansing. METHODS: Hospital-born newborns in Kathmandu, Nepal were randomly allocated to full-body skin cleansing with 0.25%, 0.50%, or 1.00% chlorhexidine solution. Skin swabs were collected from the axilla, inguinal, and peri-umbilical areas before cleansing (baseline), and at 2 and 24 hours after treatment. Skin flora was quantified and organisms identified. In a subsample, heel prick blood was collected 24 hours after the cleansing and percutaneous absorption of chlorhexidine was assessed. RESULTS: Among 286 enrolled newborns, no adverse effects on skin were reported and body temperature was minimally reduced (mean reduction, 0.33 degrees C). In all groups, positive skin culture rates were significantly reduced at 2 hours but generally not at 24 hours; greater reductions were observed with higher concentrations of chlorhexidine. Effect at 24 hours was highest in the 1.00% group (37% lower positive skin culture rate). For 15 of 75 infants with heel pricks, chlorhexidine was detected at trace concentrations (<8 ng/mL, n = 14; 25.8 ng/mL, n = 1). CONCLUSIONS: Chlorhexidine skin cleansing seemed safe and reduced skin flora in newborns in a dose-dependent manner 2 hours after treatment. Greater residual effect at the highest concentration (1%) might provide broader benefit and may simplify combined maternal and neonatal regimens by matching the concentration used for vaginal cleansing during labor.  相似文献   
259.
BALB/c mice were infected with Mycobacterium lepraemurium in the footpad or with Mycobacterium bovis BCG intravenously with 5 x 10(7) bacilli. Recombinant interleukin-2 (IL-2) was injected intraperitoneally as a single dose (20,000 U), as a single course of five injections (400 U each), or as a 6-month course starting 3 days after the M. lepraemurium infection. BCG-infected mice received a single dose (1,000 U) or five daily injections of 100 or 1,000 U each. IL-2 significantly reduced the total bacterial counts in the footpad, lymph nodes, and liver of M. lepraemurium-infected mice (50 to 85%) by 6 months and viable counts in the spleen (30 to 50%) by 60 days after BCG infection. The courses of IL-2 started at 60 days were more effective than those started at 3 days after M. lepraemurium infection (P less than 0.05 to 0.001), and for BCG, 100 U of IL-2 was better than 1,000 U (P less than 0.05 to 0.01). These results indicate that IL-2 limits mycobacterial infections in mice and raise the question of its possible use in humans.  相似文献   
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