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71.
The aim of this article is to report a case of symptomatic fibromuscular dysplasia (FMD) involving the external iliac arteries (EIAs). An 88-year-old woman was admitted to the vascular service, with a painful right posterior ankle ulcer that had progressively worsened during the course of a month. Her medical history included diabetes and hypertension. Bilateral lower-extremity pulses were absent, and femoral and tibial Doppler waveforms were monophasic. Pelvic and bilateral lower-extremity angiograms were obtained, which revealed findings in both EIAs consistent with a diagnosis of extrarenal FMD. Percutaneous transluminal angioplasty with subsequent stenting of the right EIA was performed, using a self-expanding stent. Completion digital subtraction angiography demonstrated a widely patent right EIA with brisk flow of contrast across the stent. Postprocedural arterial duplex scan showed a biphasic waveform pattern in the common femoral artery. FMD can involve the EIA and be associated with critical limb ischemia. FMD of the EIA responds well to endovascular management.  相似文献   
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During the induction of long-term potentiation (LTP) in hippocampal slices adenosine triphosphate (ATP) is secreted into the synaptic cleft, and a 48 kDa/50 kDa protein duplex becomes phosphorylated by extracellular ATP. All the criteria required as evidence that these two proteins serve as principal substrates of ecto-protein kinase activity on the surface of hippocampal pyramidal neurons have been fulfilled. This phosphorylation activity was detected on the surface of pyramidal neurons assayed after synaptogenesis, but not in immature neurons nor in glial cells. Addition to the extracellular medium of a monoclonal antibody termed mAb 1.9, directed to the catalytic domain of protein kinase C (PKC), inhibited selectively this surface protein phosphorylation activity and blocked the stabilization of LTP induced by high frequency stimulation (HFS) in hippocampal slices. This antibody did not interfere with routine synaptic transmission nor prevent the initial enhancement of synaptic responses observed during the 1-5 min period immediately after the application of HFS (the induction phase of LTP). However, the initial increase in the slope of excitatory postsynaptic potentials, as well as the elevated amplitude of the population spike induced by HFS, both declined gradually and returned to prestimulus values within 30-40 min after HFS was applied in the presence of mAb 1.9. A control antibody that binds to PKC but does not inhibit its activity had no effect on LTP. The selective inhibitory effects observed with mAb 1.9 provide the first direct evidence of a causal role for ecto-PK in the maintenance of stable LTP, an event implicated in the process of learning and the formation of memory in the brain.  相似文献   
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The value of unenhanced spiral CT (UESCT) for investigating acute flank pain suggestive of urinary tract calculi is increasingly appreciated in the last few years. Recent studies have identified the advantages of UESCT in recognizing alternative findings within or outside the urinary tract. We sought to determine how narrowing the referral base for the UESCT would affect the discovery of potentially significant alternative findings in patients with acute flank pain suggestive of renal colic. Between January 1999 and December 1999, 425 patients, 271 (63.8%) men and 154 (36.2%) women who were 1-90 years old (mean 45.7 years old) with acute flank pain were studied with UESCT. CT studies were solely ordered by urologists, and only patients with intractable renal colic or patients that returned more than once to the emergency room with the complaint of acute flank pain were studied. A calculus within the ureter was diagnostic of an obstructive stone. Any other abnormality within the abdomen and pelvis was reported. A ureteral calculus was detected on 251 (59%) CT scans. Nineteen (4.5%) CT scans were consistent with recent excretion of a stone. In 112 (26.3%) CT scans, the cause for the patient's acute flank pain could not be explained. Forty-three (10.1%) alternative significant diagnoses that explain the patient's complaints were found. Nineteen (44%) were findings related to the urinary tract, and 24 (56%) were not related to the urinary tract. Ninety-seven (22.3%) additional findings not significant to the patient's current complaint were also reported. Even when narrowing the indications for the UESCT, about 10% of significant alternative findings to urinary stones were encountered. The variety of diagnoses found unexpectedly on the UESCT that alter a patient's management demonstrates the pivotal role of UESCT in triaging these patients rapidly towards optimal therapy. The UESCT can be used as a useful screening tool, sometimes revealing the exact pathology and sometimes directing the radiologist to the modality by which to continue.  相似文献   
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Objective

An upper arm brachiobasilic arteriovenous fistula (BBAVF) is a reliable autogenous hemodialysis access created with a one-stage or two-stage technique. Although both techniques are variably used, the optimal approach is uncertain. In this study, we compared the outcomes of one-stage and two-stage BBAVF procedures.

Methods

We identified 2648 patients who had received BBAVFs within the Vascular Quality Initiative data set (2010-2016) and compared those created using the one-stage and two-stage technique. The primary outcome measures were primary and secondary patency rates at 12 months. Other outcomes assessed were wound infection, steal, and swelling at 3 months. The log-rank test was used to evaluate patency by Kaplan-Meier analysis. Cox proportional hazards models were used to examine the adjusted association between surgical technique and outcomes.

Results

There were 1234 (47%) one-stage and 1414 (53%) two-stage BBAVFs in the study cohort, including 1848 (70%) patients who were on dialysis at the time of surgery and 1795 (68%) patients with a history of previous access. Patients who underwent a one-stage BBAVF were more likely to be male (54% vs 45%; P < .001), to be white (60% vs 41%; P < .001), and to have a history of coronary artery disease (22% vs 17%; P = .001). Patients undergoing one-stage BBAVFs have larger vein diameters (4.1 vs 3.4 mm; P < .001) and have the procedure in an inpatient setting (21% vs 13%; P < .001) compared with patients undergoing a two-stage procedure. The 12-month primary patency rate was higher for the one-stage BBAVF (49.1% vs 40.4%; P = .005), although the secondary patency rate was comparable (80.0% vs 77.9%; P = .54). Postoperative bleeding (4% vs 1.5%; P < .001), wound infection (1.01% vs 0.4%; P = .047), and arm swelling (2.1 % vs 0.8%; P = .006) were higher for one-stage BBAVFs. In multivariable analysis, although loss of primary patency at 12 months (adjusted hazard ratio [aHR], 1.12; 95% confidence interval [CI], 0.97-1.30; P = .12) and 3-month wound infection (aHR, 0.42; 95% CI, 0.14-1.25, P = .12) were similar between the two approaches, the risk of 3-month arm swelling was significantly lower for two-stage BBAVFs (aHR, 0.35; 95% CI, 0.16-0.77; P = .009).

Conclusions

Whereas surgeons were more likely to perform a two-stage BBAVF in patients with a history of previously failed access and smaller basilic vein, our data show no difference in primary or secondary patency of one-stage and two-stage BBAVFs at 12 months.  相似文献   
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Studies of human cytomegalovirus (HCMV) UL97 kinase deletion mutant (DeltaUL97) indicated a multi-step role for this kinase in early and late phases of the viral life cycle, namely, in DNA replication, capsid maturation and nuclear egress. Here, we addressed its possible involvement in cytoplasmic steps of HCMV assembly. Using the DeltaUL97 and the UL97 kinase inhibitor NGIC-I, we demonstrate that the absence of UL97 kinase activity results in a modified subcellular distribution of the viral structural protein assembly sites, from compact structures impacting upon the nucleus to diffuse perinuclear structures punctuated by large vacuoles. Infection by either wild type or DeltaUL97 viruses induced a profound reorganization of wheat germ agglutinin (WGA)-positive Golgi-related structures. Importantly, the viral-induced Golgi remodeling along with the reorganization of the nuclear architecture was substantially altered in the absence of UL97 kinase activity. These findings suggest that UL97 kinase activity might contribute to organization of the viral cytoplasmic assembly sites.  相似文献   
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