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91.
京杭大运河的贯通,使临清迅速成为各地商贸滋聚之地.在规模、人口和经济繁荣程度上,临清都是全国性的一流大城市.鳌头矶是临清的一个特殊生长点,是临清最具代表性的地点,同时也是临清人文景观的亮点.它集中展示了临清城市的生命历程,也展示了这个城市的精神本质和作为大都会的文化生命意义.运河强烈地改变着临清人的价值观念、生产价值模式、消费观念,以及日常生活及其审美观念.运河提升了临清的精神结构,使临清深受江南既重利又重文的城市精神的浸染,绝不类于一般北方城市.  相似文献   
92.

Objective

It has long been known that hydroxymethylglutaryl-coenzyme A reductase inhibitors (statins) broadly reduce cardiovascular events in patients with peripheral vascular disease. It was the goal of this study to determine whether there is an association between statin therapy and primary patency after stenting of superficial femoral and popliteal arteries.

Methods

The records of all patients undergoing primary nitinol stenting of the femoral and popliteal arteries at a single institution and by a single surgeon during a 10-year period were reviewed. Demographic characteristics of the patients and risk factors were identified. TransAtlantic Inter-Society Consensus (TASC II) classifications were determined for all stented lesions. Analysis was performed to determine whether the use of statins at the time of stent placement was associated with a change in rates of primary patency. Loss of primary patency was said to have occurred when an intrastent occlusion or a ≥70% stenosis was identified by arterial duplex ultrasound or angiography. Kaplan-Meier survival curves were plotted, and differences between groups were tested by log-rank method.

Results

Between 2004 and 2014, primary femoral or popliteal stenting was performed on 308 limbs in 250 patients. At the time of intervention, 52.4% of these patients were being treated with statin therapy; 137 interventions were done for claudication and 113 for critical limb ischemia. Of the lesions treated, 165 were TASC A or B and 85 were TASC C or D. Primary patency rates for all stented lesions were 75%, 54%, and 35% at 12, 24, and 36 months. The patency rates at 12, 24, and 36 months, respectively, were 80%, 55%, and 40% for those taking statins and 68%, 49%, and 28% for those not taking statins (P = .178). Statin therapy demonstrated a trend toward an association with improved primary patency rates in TASC A/B lesions but had no association in TASC C/D lesions (TASC A/B, P = .056; TASC C/D, P = .537). Statin compliance was found to be 87% at a mean follow-up of 24.1 months.

Conclusions

Although the use of statins has been shown to reduce cardiovascular morbidity and mortality in patients with peripheral vascular disease, overall there is not an association of these drugs with improved primary patency after primary stenting of femoral and popliteal artery lesions. However, when limbs are stratified for severity, less severe (TASC A/B) lesions demonstrated a trend toward a significant association between statin use and improved primary patency. This finding was not seen in more severe (TASC C/D) disease.  相似文献   
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96.

Background

The influence of diabetic therapies on myocardial substrate selection during cardiac surgery is unknown but may be important to ensure optimal surgical outcomes. We hypothesized that metformin and insulin alter myocardial substrate selection during cardiac surgery and may affect reperfusion cardiac function.

Methods

Rat hearts (n?=?8 per group) were evaluated under 3 metabolic conditions: normokalemia, cardioplegia, or bypass. Groups were perfused with Krebs-Henseleit buffer in the presence of no additives, metformin, insulin, or both insulin and metformin. Perfusion buffer containing physiologic concentrations of energetic substrates with different carbon-13 (13C) labeling patterns were used to determine substrate oxidation preferences using 13C magnetic resonance spectroscopy and glutamate isotopomer analysis. Rate pressure product and oxygen consumption were measured.

Results

Myocardial function was not different between groups. For normokalemia, ketone oxidation was reduced in the presence of insulin and the combination of metformin and insulin reduced fatty acid oxidation. Metformin reduced fatty acid and ketone oxidation during cardioplegia. Fatty acid oxidation was increased in the bypass group compared with all other conditions.

Conclusion

Metformin and insulin affect substrate utilization and reduce fatty acid oxidation before reperfusion. These alterations in substrate oxidation did not affect myocardial function in otherwise normal hearts.  相似文献   
97.

Introduction

and aim. Poor functional status is associated with increased mortality in cirrhosis patients awaiting liver transplantation (LT); however, the optimal assessment of functional status remains unknown. This study sought to determine the relationship between 6-minute walk distance (6MWD) and Karnofsky Performance Status (KPS) and their association with waitlist mortality in LT candidates.

Material and methods

Two hundred seventy-eight consecutive patients listed for LT were included. KPS and 6MWD were assessed at the time of evaluation. KPS was recorded as a percentage from 0 to 100, with 0 representing death and 100 representing no presence of disease. Patients were followed from time of listing until transplantation, death, removal from the waitlist or end of the study period.

Results

The mean KPS and 6MWD were 77.4 ± 13.5 and 323.6 ± 163.9 m, respectively. A mild correlation between 6MWD and KPS was demonstrated (Spearman ρ = 0.4317, P < .0001). KPS was significantly lower in patients with 6MWD < 250 meters (P < .0001). The 6MWD was significantly lower in patients who suffered waitlist mortality (266.1 vs 331.8 m, P = .05).

Conclusion

In conclusion, 6MWD is a better predictor of waitlist mortality than KPS score in candidates for LT. The addition of 6MWD as a standard assessment may help to identify patients at risk of dying on the waitlist.  相似文献   
98.

Background

Patients with cirrhosis and end-stage liver disease (ESLD) develop severe nutrition deficits that affect morbidity and mortality. Laboratory measures of nutrition fail to fully assess clinical deficits in muscle mass and fat stores. This study employs computed tomography imaging to assess muscle mass and subcutaneous and visceral fat stores in patients with ESLD.

Methods

This 1:1 case-control study design compares ESLD patients with healthy controls. Study patients were selected from a database of ESLD patients using a stratified method to assure a representative sample based on age, body mass index (BMI), sex, and model for end-stage liver disease score (MELD). Control patients were trauma patients with a low injury severity score (<10) who had a computed tomography scan during evaluation. Cases and controls were matched for age ± 5 years, sex, and BMI ± 2.

Results

There were 90 subjects and 90 controls. ESLD patients had lower albumin levels (P < .001), but similar total protein levels (P = .72). ESLD patients had a deficit in muscle mass (?19%, P < .001) and visceral fat (?13%, P < .001), but similar subcutaneous fat (?1%, P = .35). ESLD patients at highest risk for sarcopenia included those over age 60, BMI<25.0, and female sex. We found degree of sarcopenia to be independent of model for end-stage liver disease score.

Conclusions

These results support previous research demonstrating substantial nutrition deficits in ESLD patients that are not adequately measured by laboratory testing. Patients with ESLD have significant deficits of muscle and visceral fat stores, but a similar amount of subcutaneous fat.  相似文献   
99.

Background

A variety of devices exist for endovascular aneurysm repair (EVAR). Device-specific instructions for use (IFU) detail anatomic constraints to application and deployment of devices and are developed from rigorous bench testing. Nonadherence to IFU occurs frequently to avoid open surgery. The purpose of this study was to determine if IFU violations are associated with increased risk of graft-related adverse events (GRAEs) during follow-up.

Methods

This multicenter retrospective observational study included patients undergoing elective endovascular repair for abdominal aneurysmal disease with three different devices. Demographics, anatomic data, and follow-up data were collected on patients from 2005 to 2014. IFU violations were device specific and included neck diameter, length, and angulation and iliac artery diameter and length. GRAEs included a composite outcome of reintervention, migration, endoleak (type II excluded), rupture, limb occlusion, sac growth, and aneurysm-related mortality during the follow-up period. Kaplan-Meier survival and Cox proportional hazards modeling were performed. Any IFU violations as well as neck-specific IFU violations were analyzed.

Results

In 461 patients undergoing EVAR, 43.8% had at least one IFU violation. Patients with IFU violations were more likely to have peripheral vascular disease (12.4% vs 7.3%) and were less likely to be male (78.7% vs 90.3%). The most frequent IFU violations included diameter deviations of the neck (15.2%) and of the iliac artery (21.4%). Overall, the GRAE rate was 12.8%. Median follow-up time was 1.9 and 2.1 years for patients with and without an IFU violation, respectively. Kaplan-Meier survival revealed a significant association between the presence of an IFU violation and GRAEs (log-rank, P = .031). When adjusted for clinical variable through Cox hazard modeling, the association remained significant (hazard ratio 1.8; 95% confidence interval, 1.05-3.1). When neck-specific violations were considered independently, Kaplan-Meier survival (log-rank, P = .003) and Cox modeling (hazard ratio, 2.2; 95% confidence interval, 1.2-4.0) revealed a significant association between neck-specific IFU violation and GRAEs.

Conclusions

A total of 43.8% of patients undergoing EVAR had a device-specific IFU violation, indicating that implanters are pushing the boundaries of device capabilities. Our study identified that any IFU violation was significantly associated with GRAEs over time. Caution should be applied to patients being considered for EVAR when IFU deviations exist.  相似文献   
100.
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