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91.
92.

Objective

The aim of the study was to identify factors influencing surgical treatment outcome following upper extremity arterial injuries.

Methods

This 15-year study (January 1992 to December 2006) included 167 patients with 189 civilian, iatrogenic or military upper extremity arterial injuries requiring surgical intervention. Patient data were prospectively entered into a vascular trauma database and retrospectively analysed.

Results

The most frequently damaged vessel was the brachial artery (55% of injuries), followed by the axillary (21.7%), antebrachial (21.2%) and subclavian (2.1%) arteries. Three primary amputations (1.8%) were performed because of extensive soft-tissue destruction and signs of irreversible ischaemia on admission. Seven secondary amputations (4.2%) were due to graft failure, infection, anastomotic disruption or the extent of soft-tissue and nerve damage. Fasciotomy was required in 9.6% of cases. Operative mortality was 2.4% (four deaths). Early graft failure, compartment syndrome, associated skeletal and brachial plexus damage and a military mechanism of injury were found to be significant risk factors for limb loss (p < 0.01).

Conclusion

Although careful physical examination should diagnose the majority of upper extremity arterial injuries, angiography is helpful in detailing their site and extent. Prompt reconstruction is essential for optimal results. Nerve trauma is the primary cause of long-term functional disability.  相似文献   
93.
The aim of this study was to assess the validity of a fast ramp treadmill protocol for determination of the heart rate deflection point (HR (dp)) and speed of deflection (S (dp)) in trained runners. Fifty-one trained male runners performed a standard (T (stand); speed increase 1 km . h (-1) every 60 s) and a fast (T (fast); speed increase 1 km . h (-1) every 30 s) incremental treadmill test until volitional exhaustion. Heart rate was continuously recorded, and the HR (dp) was estimated after data averaging as the point of deflection in the linear speed/HR relationship. The HR (dp) and S (dp) recorded in T (fast) were compared with the corresponding values obtained in T (stand) by examining the Student's T-test, correlation coefficient (r), and limits of agreement (LoA). The HR (dp) recorded during standard and fast treadmill protocol were highly correlated (r = 0.92, p < 0.001) and similar to each other (p = 0.79). In contrast, S (dp) was highly correlated (r = 0.91, p < 0.001), but increased significantly with the faster ramp function (p < 0.001). No evidence of systematic bias was evident in the HR (dp) (95 % LoA of 0.2 +/- 7.3 bpm), while a uniform, systematic bias was evident for S (dp) in the T (fast) (95 % LoA of 1.6 +/- 1.5 km x h (-1)). We conclude that a fast ramp treadmill protocol (speed increase 1 km x h (-1) every 30 s) may be used for determination of the HR (dp) in trained runners, while S (dp) is protocol dependent and caution is warranted regarding its practical applicability.  相似文献   
94.
Markovic G 《British journal of sports medicine》2007,41(6):349-55; discussion 355
The aim of this study was to determine the precise effect of plyometric training (PT) on vertical jump height in healthy individuals. Meta-analyses of randomised and non-randomised controlled trials that evaluated the effect of PT on four typical vertical jump height tests were carried out: squat jump (SJ); countermovement jump (CMJ); countermovement jump with the arm swing (CMJA); and drop jump (DJ). Studies were identified by computerised and manual searches of the literature. Data on changes in jump height for the plyometric and control groups were extracted and statistically pooled in a meta-analysis, separately for each type of jump. A total of 26 studies yielding 13 data points for SJ, 19 data points for CMJ, 14 data points for CMJA and 7 data points for DJ met the initial inclusion criteria. The pooled estimate of the effect of PT on vertical jump height was 4.7% (95% CI 1.8 to 7.6%), 8.7% (95% CI 7.0 to 10.4%), 7.5% (95% CI 4.2 to 10.8%) and 4.7% (95% CI 0.8 to 8.6%) for the SJ, CMJ, CMJA and DJ, respectively. When expressed in standardised units (ie, effect sizes), the effect of PT on vertical jump height was 0.44 (95% CI 0.15 to 0.72), 0.88 (95% CI 0.64 to 1.11), 0.74 (95% CI 0.47 to 1.02) and 0.62 (95% CI 0.18 to 1.05) for the SJ, CMJ, CMJA and DJ, respectively. PT provides a statistically significant and practically relevant improvement in vertical jump height with the mean effect ranging from 4.7% (SJ and DJ), over 7.5% (CMJA) to 8.7% (CMJ). These results justify the application of PT for the purpose of development of vertical jump performance in healthy individuals.  相似文献   
95.
The majority of locoregional recurrences in melanoma occur in the form of intradermal or subcutaneous local or in-transit metastasis. In-transit melanoma represents contamination of the lymphatic space that, if treated, can result in long-term cure in a subset of patients. The management of in-transit metastases is challenging, since the treatments and extent of disease vary greatly based on the number, depth, location, and distribution of lesions, and on their biological behavior. A number of different treatment options exist, but there is no level 1 evidence to guide clinical decision-making. Herein we present our institutional treatment algorithm, which allows for individualization based on the patient's presentation.  相似文献   
96.
随着检测技术进步,含7个跨膜α螺旋结构的受体性质已渐为人们所了解。7次跨膜(7TM)受体不仅具有开关功能,更类似于信息微处理器;特定配体只能参与特定受体介导的部分信号机制,这就为药物发现开拓了一个新领域。为进一步发现7TM受体与配体间的新行为并量化评价药物对这一复杂系统的作用效能,进而指导药物化学研究,药理学检测已成为关注焦点。本文阐述从还原重组体到整体系统测定方法的回归,讨论药物效价与评价其效应的特定检测方法间的联系,强调新的检测方法在药物发现过程中的价值。  相似文献   
97.
98.
Apelin constitutes a novel endogenous peptide system suggested to be involved in a broad range of physiological functions, including cardiovascular function, heart development, control of fluid homeostasis, and obesity. Apelin is also a catalytic substrate for angiotensin-converting enzyme 2, the key severe acute respiratory syndrome receptor. The in vivo physiological role of Apelin is still elusive. Here we report the generation of Apelin gene-targeted mice. Apelin mutant mice are viable and fertile, appear healthy, and exhibit normal body weight, water and food intake, heart rates, and heart morphology. Intriguingly, aged Apelin knockout mice developed progressive impairment of cardiac contractility associated with systolic dysfunction in the absence of histological abnormalities. We also report that pressure overload induces upregulation of Apelin expression in the heart. Importantly, in pressure overload-induced heart failure, loss of Apelin did not significantly affect the hypertrophy response, but Apelin mutant mice developed progressive heart failure. Global gene expression arrays and hierarchical clustering of differentially expressed genes in hearts of banded Apelin(-/y) and Apelin(+/y) mice showed concerted upregulation of genes involved in extracellular matrix remodeling and muscle contraction. These genetic data show that the endogenous peptide Apelin is crucial to maintain cardiac contractility in pressure overload and aging.  相似文献   
99.
DHAP (dexamethasone, cytosine arabinoside and cis-platinum) is a commonly used regimen for relapsed or refractory diffuse large B-cell lymphoma (DLBCL). The optimal treatment for patients who do not respond to DHAP, but are still potential candidates for autologous stem cell transplantation, is unclear. One option is to proceed with an alternative chemotherapy regimen such as ifosfamide, carboplatin, and etoposide (ICE). The overall response rate (ORR) and overall survival (OS) associated with this chemotherapy sequence is unknown. Patients with DLBCL receiving DHAP as the first salvage therapy without response followed by ICE as second salvage were studied to learn the ORR to ICE and OS. The ORR to ICE in these DHAP-failures was 52% (11/21) with 14% (3/21) complete responses and 38% (8/21) partial responses. Nine patients (43%) were able to proceed to transplant and 29% (6/21) are long-term survivors. In patients with stable disease after DHAP the ORR was 67% (8/12) with 42% (5/12) becoming long-term survivors. In contrast, only 33% (3/9) of patients who had progressive disease on DHAP responded to ICE with only one patient achieving a durable response. Patients with stable disease after DHAP can be salvaged with ICE-based chemotherapy regimens whereas patients who progress on DHAP have a poor outcome. Patients with progressive disease on DHAP should be considered for alternative salvage regimens or experimental therapy.  相似文献   
100.
Vascular calcification is a recognized risk factor for cardiovascular mortality in patients with end-stage renal disease. The aim of this study was to identify risk factors for vascular access calcification and to determine if patients with this disorder are at increased risk of death. Vascular access calcification was found in 49 of 212 hemodialysis patients as measured by plain X-ray (arteriovenous fistula or synthetic graft) in two dimensions. Male gender, diabetes mellitus, and length of time on dialysis were independent predictors for access calcification determined by logistic regression multivariate analysis. Serum parameters were not independently related to access calcification. Kaplan-Meier analysis showed an increased mortality risk, and Cox regression analysis confirmed that vascular access calcification was an independent mortality predictor. Our study suggests that detection of vascular access calcification is a cost-effective method to identify patients at increased mortality risk.  相似文献   
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