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671.
The purpose of the study was to investigate the effect of different ventilatory strategies on local and systemic cytokine production in swine with intact lungs in vivo after 4 h of mechanical ventilation. Twenty-five swine were anesthetized and then randomized into five groups (n = 5): (1) low tidal volume zero PEEP (LVZP); (2) medium tidal volume zero PEEP (MVZP); (3) high tidal volume zero PEEP (HVZP); (4) low tidal volume PEEP (LVP); (4) high tidal volume PEEP (HVP). Respiratory rate was adjusted to maintain normocapnia and fraction of inspired oxygen (FiO2) was 1.0. TNF-alpha and IL-10 were measured in BALF and serum at baseline, 2 h, and 4 h of MV. One animal in LVZP (2 h) and two in HVP (3 h) group died before the end of the experiment. TNF-alpha level in BALF was significantly higher in LVZP and LVP at 4 h compared to baseline and the other groups. IL-10 level in BALF was significantly higher in LVP at 4h compared to baseline and the other groups. There was a statistically significant increase in serum TNF-alpha levels at 4 h in LVP group compared to baseline and the other groups at 4 h. There was statistically significant increase in serum IL-10 levels in HVZP and LVP groups at 2 and 4 h which was significantly higher compared to the other groups at 4 h. Our results show that a) low volume MV may induce local and systemic pro- and anti-inflammatory cytokine increase b) in the presence of pro-inflammatory cytokine response there is also an anti-inflammatory response in the same compartment (lungs, circulation). c) There maybe loss of alveolar-to-systemic cytokine compartmentalization.  相似文献   
672.
Cutaneous T cell lymphomas (CTCLs) are a heterogenous group of lymphoproliferative disorders caused by clonally-derived, skin-invasive T cells. A variety of skin-directed and systemic therapies are available to treat mycosis fungoides/Sézary syndrome (MF/SS), the therapeutic choices of which are guided by the stage of disease. A 29-year-old man presented at our clinic with pruritic, erythematous macules located on the sternum and the lower back. Histological findings and immunohistochemistry studies showed patch stage MF. The patient was treated with tacrolimus ointment 0.1% twice daily for one month, achieving complete remission. Three months after the first episode a relapse was successfully treated with the same therapeutic regimen. Tacrolimus is an immunomodulatory macrolide that reduces the stimulatory capacity toward T cells and is therefore worth investigating as a treatment of CTCL. Topical tacrolimus has been related to an unknown effect with the risk for secondary malignancies including CTCL. Also, black box warnings have been proposed by the FDA for the topical calcineurin inhibitors. Nevertheless, our results in the treatment of early stage MF are in agreement with other unpublished data that have observed its efficacy. To our knowledge, there is no other case of patch type mycosis fungoides treated with tacrolimus ointment 0.1% in the medical literature.  相似文献   
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674.
BACKGROUND: Renovascular hypertension is the most common curable form of secondary hypertension. Renin angiotensin system activation depends on the balance between renin production by the kidney and renin degradation by the liver. Thus, we aimed to examine whether deviation of renin-rich blood from the affected kidney into the portal circulation (portalization) can ameliorate renovascular hypertension. METHODS: We selected a porcine model of unilateral renal artery stenosis because the pig's anatomy and physiology are comparable to those of humans and because pigs have already been found capable of developing chronic renovascular hypertension. Angiography and ultrasonography were deliberately used to evaluate renal artery stenosis and the renal-portal shunt. Histology was used to examine the effects of portalization on the kidney and liver after a period of two months. RESULTS: As expected, following the creation of a left renal artery stenosis both renin activity and mean blood pressure measurements increased from 1.23 +/- 0.06 ng/mL/h and 85.6 +/- 0.5 mm Hg at baseline to 4.59 +/- 0.02 ng/mL/h and 126 +/- 1.76 mm Hg, respectively. After portalization renin activity returned to the normal range (1.59 +/- 0.07 ng/mL/h) followed by a concomitant reduction of mean blood pressure to 91 +/- 2 mm Hg. Moreover, a significant correlation was observed between changes in renin activity and blood pressure measurements during the two stages of the experiment. Both the kidney and liver remained macroscopically and microscopically intact at the end of the experiment. CONCLUSION: Portalization of the affected kidney can ameliorate renovascular hypertension and therefore, it might be of benefit in those individuals with fibromascular or atheromatous lesions in the renal artery or its branches not amenable to balloon angioplasty or surgical revascularization.  相似文献   
675.
In this article there is an attempt, to critically review the literature referring to the clinical validity and clinical applications of in vivo imaging of infected areas of our body, with 99mTc-ciprofloxacin (infection). Infection is the product of labeling a broad spectrum antibiotic, ciprofloxacin, with 99mTc. There is increased interest and expectation that this agent will become a useful tool for every day clinical practice, in discriminating, infectious from inflammatory lesions. Although this radiopharmaceutical is not widely available, a number of papers have been published recently regarding clinical and experimental trials with this agent. There is some debate regarding its production procedure and its specificity in discriminating infection from inflammation. Comparison with other infection-imaging agents is described, as well as its clinical validity in specific clinical situations.  相似文献   
676.
677.
Smoking is associated with endothelial dysfunction and abnormalities in thrombosis/fibrinolysis system, possibly through increased oxidative stress. In this study we investigated the effect of combined antioxidant treatment with vitamins C and E on endothelial function and plasma levels of plasminogen activator inhibitor (PAI-1), von Willebrand factor (vWF), tissue plasminogen activator (tPA) and factor VII (fVII), in smokers. Forty-one healthy smokers were randomly divided into 4 groups receiving vitamin C 2g/day (group A), vitamin C 2g/day plus vitamin E 400 IU/day (group B), vitamin C 2g/day plus vitamin E 800 IU/day (group C) or no antioxidants (controls, group D), for 4 weeks. Forearm blood flow was measured using venous occlusion strain-gauge plethysmography. Forearm vasodilatory response to reactive hyperemia (RH%) or to sublingual nitroglycerin administration (NTG%) were considered as indexes of endothelium dependent or independent dilation respectively. After treatment, RH% was increased only in groups B (p <0.05) and C (p <0.001) but not in groups A and D. Plasma levels of PAI-1 and vWF were decreased only in group C (p <0.05 for both), while PAI-1/tPA ratio was significantly decreased in both groups B and C (p <0.05 for both). NTG% and plasma levels of tPA and fVII remained invariable in all groups. In conclusion, combined administration of vitamin C and vitamin E at high dosages, improved endothelial function and decreased plasma levels of PAI-1, vWF and PAI-1/tPA ratio in chronic smokers.  相似文献   
678.
679.
Background: Bariatric surgery in patients >50 years has been controversial. We investigated the safety and efficacy of laparoscopic Roux-en-Y gastric bypass (LRYGBP) in patients >55 years of age. Methods: Prospective data on 71 patients (54 females and 17 males) undergoing LRYGBP were reviewed. The patients were followed for a mean of 17 months (range 2-35 months). Results: The mean age was 59 years (range 55-67 years), and the mean preoperative BMI was 50.2 kg/m2 (range 37-65 kg/m2). There were no conversions to open technique. Mean percent of excess weight loss (%EWL) was 20%, 48%, 64% and 67% at 1, 6, 12 and 24 months respectively. 89% of patients had at least a 50% EWL at 1 year postoperatively. There was a significant decrease in the number of patients requiring medical treatment for co-morbidities associated with morbid obesity: diabetes mellitus 87%, hypertension 70% and sleep apnea 86%. There was no inpatient mortality. 1 patient died suddenly 2 weeks postoperatively of possible myocardial infarction or pulmonary embolism. 16 patients developed 22 complications. The median length of hospital stay was 3 days. Conclusion: LRYGBP is a safe and well-tolerated surgical option for the treatment of morbid obesity in patients >55 years old. These patients demonstrate a satisfactory weight loss and resolution of co-morbidities.  相似文献   
680.
Forty-two patients who underwent decompressive surgery for cervical spondylotic myelopathy were studied. The pre- and postoperative magnetic resonance imaging (MRI) findings and the Japanese Orthopedic Association score were analyzed to evaluate whether the different appearances of intramedullary high-signal intensity on T2-weighted MRI are related to the surgical prognosis. Magnetic resonance imaging signal intensities were classified as type 0 if no intramedullary high-signal intensity on T2-weighted images was noted, type 1 if high-signal intensity involved only one segment, and type 2 if high-signal intensity extended over two segments. Statistical analyses of the recovery ratio showed that type 0 and type 1 intramedullary high-signal intensity indicates better prognosis than type 2.  相似文献   
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