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Elastic recoil of the vessel wall is a common cause of failure of percutaneous transluminal angioplasty in renal arteries. To oppose such recoil, balloon-expandable metal stents were implanted in artificially stenotic renal arteries in pigs and normal renal arteries in dogs and pigs. The stents were then examined angiographically and histologically at regular intervals. All stents were completely covered with endothelialized neointima in 3 weeks. There was no difference in intimal thickness between the stenotic and nonstenotic renal arteries. A large stent diameter and a large open or nonmetal surface may cause less intimal hyperplasia, but nonturbulent, fast arterial flow is probably the most important factor in ensuring long-term patency of the vessel.  相似文献   
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The preservation of red cell antigens at low ionic strength   总被引:1,自引:0,他引:1  
Low-ionic-strength saline (LISS) techniques permit a safe and substantial reduction in incubation time and have therefore become the method of choice for antibody detection and compatibility testing in many transfusion laboratories. Consequently, the supply of reagent red cells (RBCs) in a low-ionic-strength preservative solution would remove the daily need for laboratories to wash and resuspend cells in LISS before use. However, the storage of fresh RBCs at low ionic strength in the presence of aminoglycoside antibiotics can cause a rapid loss of certain antigens, possibly as a result of the release of proteolytic enzymes from contaminating white cells. This article describes a low-ionic-strength solution that achieves preservation of antigens on liquid nitrogen-frozen-thawed RBCs for 21 days' storage at 4 degrees C.  相似文献   
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Background

Noninvasive tests are increasingly being used for the assessment of liver fibrosis. We aimed to develop a serum index for the identification of advanced fibrosis (F≥3) in HIV/hepatitis C virus (HCV)‐coinfected patients.

Methods

We carried out a cross‐sectional study on a group of 195 patients comprised of an estimation group (EG; n=127) and a validation group (VG; n=68) who all underwent liver biopsy and had not received previous interferon therapy. Liver fibrosis was estimated using the METAVIR score. We developed a new serum index (HGM‐3) dependent on levels of platelets, alkaline phosphatase, hepatic growth factor, tissue inhibitor of metalloproteinase‐1 and hyaluronic acid.

Results

In the EG, the area under the receiver operating characteristic curve (AUC‐ROC) of HGM‐3 for identification of F≥3 was 0.939 [95% confidence interval (CI) 0.899, 0.979] which was significantly higher than the AUC‐ROC of the HGM‐2, FIB‐4, aspartate aminotransferase to platelet ratio (APRI) and Forns' indexes. With HGM‐3 <0.135 for F<3, 57 patients were correctly identified and two patients were misclassified. We found the presence of F<3 with 96.6% certainty. The negative likelihood ratio (LR) was <0.1 and the diagnostic odds ratio (DOR) was >40. With HGM‐3 >0.570 in the EG for F≥3, 31 patients were correctly identified, and five patients were misclassified. We found the presence of F≥3 with 86.1% certainty. The positive LR was >12 and the DOR was >40. For the VG, the diagnostic accuracy values were similar to the values for the EG.

Conclusions

HGM‐3 appears to be an accurate noninvasive method for the diagnosis of bridging fibrosis and cirrhosis in HIV/HCV‐coinfected patients.  相似文献   
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