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21.

Background

Several postoperative gastrointestinal complications are attributed to ischemia. We herein evaluate the gastric wall perfusion using computed tomography (CT) scan perfusion index on trial to address the etiology of ischemic complication after sleeve gastrectomy.

Methods

A retrospective study of 205 patients undergoing CT scan of the abdomen to evaluate the pattern of gastric vascular perfusion was performed. The perfusion index of the gastric mucosa was measured at 5 gastric points using CT perfusion scanning.

Results

Gastric perfusion at the angle of His (AOH) (53.51 ± 14.38) was statistically significantly lower (P < .001) than that at the other gastric points studied: fundus, greater curvature, lesser curvature, incisura angularis, and mid gastric points (76.16 ± 15.21, 73.27 ± 16.55, 76.12 ± 16.12, and 75.24 ± 14.9, respectively). Gastric perfusion was significantly lower at all the gastric points (and especially so at the AOH) among obese patients (33 cases) compared with nonobese patients (18 cases). Gastric perfusion at all the points studied showed a decrease as the body mass index increases. Hypertensive patients had a better gastric perfusion compared with nonhypertensive patients.

Conclusions

Gastric wall perfusion is statistically significantly decreased at the AOH and gastric fundus compared with perfusion at other gastric points. Gastric perfusion at all the gastric points studied decreased with the increase in body mass index. Gastric leakage in obese patients following sleeve gastrectomy could be attributed to a decrease in the blood supply at AOH.  相似文献   
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We present a patient with acute abdomen and digestive bleeding caused by jejunal diverticulosis. Jejunal diverticulosis, mainly asymptomatic, when is symptomatic have a wide clinical spectrum, ranging from chronic anemic syndrome to acute abdomen. In this communication, we reviewed the clinical presentation, the pathogenesis and the treatment this infrequent pathology.  相似文献   
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Unfortunately, the only approved medical treatment for type 1 diabetes mellitus (DM) is insulin, despite the fact that tight control cannot be reached without some serious side effects such as hypoglycemia and weight gain. More and more importance is now shifted towards developing new drugs that can reach a better glycemic control with lesser side effects. Some of these promising drugs are the glucagon-like peptides 1 (GLP-1) and their agonists, which have been FDA approved for the treatment of type 2 DM. The purpose of this article is to review all of the relevant literature on the potential role of GLP-1 in the treatment of type 1 DM. The major source of data acquisition included Medline search strategies, using the words "type 1 diabetes mellitus" and "GLP-1." Articles published in the last 20?years were screened. GLP-1 increases insulin secretion in humans with existing beta cells; it also decreases glucagon secretion, and blunts appetite. Of note, new animal studies demonstrate a role in beta cell-proliferation and decreased apoptosis. Because of all the effects mentioned above, GLP-1 seems to be a promising drug for type 1 DM treatment, but more studies are still needed before solid conclusions can be drawn.  相似文献   
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International Urology and Nephrology - Vesicoureteral reflux (VUR) is the most common congenital urinary tract abnormality in children. The objective of this study was to evaluate the diagnostic...  相似文献   
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It is not known how the site of arterial administration of heparin and the timing of the activated clotting time (ACT) measurement affect the ACT during coronary interventions. We measured serial femoral venous ACTs after heparin was administered either via the angioplasty guiding catheter into the central aorta or peripherally via a sheath into the femoral artery. When heparin was administered into the central aorta, the ACT rose gradually and by 60 sec plateaued without further increase. When heparin was given into the femoral artery, the ACT displayed a marked “overshoot” early (20–270 sec after heparin) and did not plateau until sometime between 270 and 800 sec after heparin administration. We conclude that the site of administration and timing of venous sampling markedly affect the measured ACT during coronary interventions. Operators should be aware of these effects when assessing the accuracy of the ACT during coronary interventions. © 1996 Wiley-Liss, Inc.  相似文献   
30.

Introduction

Hepatic ischemia/reperfusion (I/R) injury leads to free radical generation and acute inflammatory responses that cause liver damage, an important problem for liver transplantation. Pioglitazone is known to protect I/R injury in various tissues; however, the mechanism of cytoprotection is not well understood. This study investigated the effects of pioglitazone administration in a warm hepatic I/R model on tumor necrosis factor (TNF)-α level, tissue injury, and antioxidant enzyme activity.

Materials and Methods

Eighty wistar strain rats were divided into 4 groups (n = 20): Group 1 sham hosts; Group 2 hepatic I/R; Group 3 hepatic I/R + pioglitazone (10 mg/kg); and Group 4 hepatic I/R + vehicle. Rat livers were subjected to 30 minutes of ischemia followed by 6 hours of reperfusion. After reperfusion rats were humanely killed to obtain liver tissue to study glutathione peroxidase (GPx), superoxide dysmutase (SOD), malondialdehyde (MDA) levels and for histopathologic assessment. TNF-α, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) were measured in serum.

Results

Pioglitazone pretreatment significantly reduced liver enzyme content (ALT, 176.80 ± 13.75 vs 235.28 ± 31.92 and AST, 748.20 ± 79.29 vs 944.85 ± 101.87) and TNF-α level (9:8.60 ± 8.67 vs 138.28 ± 9.99) after I/R compared with the control group. MDA level (3.02 ± 0.37 vs 4.36 ± 0.38) and hepatocytic degeneration were reduced in the pioglitazone-treated group. GPx (2.40 ± 0.25 vs 1.36 ± 0.31) and SOD activity (2.22 ± 0.30 vs 1.40 ± 0.35) were significantly higher in the pioglitazone-treated group compared with the control group.

Conclusion

The present study showed that pioglitazone administration improved hepatic I/R injury that was associated with enhanced antioxidant enzyme activities and suppression of TNF-α, ALT, and AST levels. Because peroxisome proliferator-activated receptor-γ agonists are widely used to treat diabetic patients, it may be relatively easy to expand their clinical indication. However, further investigations will be required to delineate protective mechanisms by which pioglitazone attenuates hepatic tissue injury after I/R.  相似文献   
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