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11.
12.
The Harmonic Scalpel (HS) is frequently used for hepatic resection. Yet, no current study addresses its utility compared to conventional methods. We reviewed our experience with this device to determine if it decreased perioperative complications when compared to the traditional clamp crushing technique. One hundred forty-nine anatomic hepatic resections were performed at our institution from September 1992 to February 2002. Patients were divided into two groups based on the technique of resection: HS [53% (n = 79)] versus clamp crushing [47% (n = 70)]. Use of the HS was associated with a shorter mean operative time (357 +/- 15.0 vs. 404 +/- 19.1 min; p = 0.05) and a trend toward decreased blood loss (1211 +/- 125.5 vs. 1411 +/- 180.7 mL; P = NS) and transfusion requirements (2.6 +/- 0.5 vs. 1.7 +/- 0.3 units; P = 0.10). However, use of the HS was associated with a significant increase in biliary fistulas [24% (n = 19) vs. 7% (n = 5); P = 0.01]. Use of the Harmonic Scalpel was associated with decreased operative time and a trend toward decreased blood loss and transfusion requirements. Its use was also associated with a significant increase in the incidence of postoperative bile leaks, and, therefore, surgeons must be vigilant during liver parenchymal transection when using this device.  相似文献   
13.
Buell JF  Husted T  Hanaway MJ  Peddi VR  Trofe J  Gross TG  Beebe TM  First MR  Woodle ES 《Surgery》2002,132(4):754-8; discussion 758-60
BACKGROUND: Gastric cancer in the United States is often diagnosed at advanced stages, resulting in dismal outcomes. In the immunosuppressed transplant recipient population, little is known about the clinical staging and outcome of these compromised patients. METHODS: All US cases reported to the Israel Penn International Transplant Tumor Registry were retrospectively examined for patient demographics, immunosuppressive therapy, tumor characteristics, therapeutic modalities, and mortality. Statistical analysis was performed with Students t test, chi-square analysis, and log-rank analysis by the method of Kaplan-Meier. RESULTS: Gastric cancer was identified in 34 recipients: 28 (82%) were male; 24 (71%) were white. Mean age at diagnosis was 58 +/- 11 years. Twenty-four (71%) patients received kidney transplants, 7 (21%) received heart transplants, and 3 (9%) received liver transplants. Fifty percent received induction therapy, whereas 94% were maintained on calcineurin inhibitors and corticosteroids. Thirty-five percent of patients were diagnosed during evaluation for gastrointestinal symptoms, with the remaining cases discovered incidentally during endoscopy (53%) or during computed tomography (12%) performed for other reasons. Stage varied at presentation as follows: stage I (n = 6), stage II (n = 11), stage III (n = 13), and stage IV (n = 4). Incidental diagnoses resulted in a lower stage malignancy (P <.001) and greater 1-year and 5-year survivals (P <.05) compared with those patients whose were diagnosed after being evaluated of gastrointestinal symptoms. CONCLUSION: In the United States, because gastric cancer in the transplant recipient is frequently identified at an earlier stage (50% were stages I and II) than in the general population, survivals are equivalent despite continued administration of immunosuppression. This early identification may be attributed to more frequent presymptom diagnosis and staging, resulting from incidental detection of these malignancies during posttransplant upper endoscopy or computed tomography. Early detection has resulted in a 29% 5-year survival for the entire transplant recipient group compared with a 5% to 15% 5-year survival in the general population.  相似文献   
14.
BackgroundFractional flow reserve (FFR) is a valid surrogate for hemodynamic significance in stenotic native coronary arteries. The aim of this study was to examine the value of FFR compared to stress perfusion myocardial scintigraphy (SPMS) in patients with coronary stent restenosis.MethodsWe studied 42 patients, aged 62 ± 10 years, with stent restenosis 5.3 ± 1.6 months after coronary stent implantation. All patients had a single coronary lesion of intermediate severity (diameter stenosis 40–70%). FFR measurement, SPMS, and quantitative angiography of the stent stenosis were performed in all patients.ResultsThe mean percentage in stent diameter stenosis was 53 ± 9%. FFR was 0.77 ± 0.15. In 20 patients FFR was below 0.75. Nineteen patients had reversible perfusion defects in SPMS. FFR showed good diagnostic accuracy for the detection of reversible perfusion defects in SPMS (AUROC 0.86, 95% CI 0.74–0.98). The percentage of agreement of SPMS and FFR was 88%, with the best cutoff value of 0.75 for FFR.ConclusionsA FFR value of 0.75 is not only valid for diagnosing significant native coronary stenosis, but also for stent restenosis. Thus, FFR measurement should be taken into account when making decisions regarding patients with stent restenosis.  相似文献   
15.

Objectives

To help athletic trainers promote a “food-first” philosophy to support health and performance, understand federal and sport governing body rules and regulations regarding dietary supplements and banned substances, and become familiar with reliable resources for evaluating the safety, purity, and efficacy of dietary supplements.

Background

The dietary supplement industry is poorly regulated and takes in billions of dollars per year. Uneducated athletes need to gain a better understanding of the safety, eligibility, and efficacy concerns associated with choosing to take dietary supplements. The athletic trainer is a valuable athletic team member who can help in the educational process. In many cases, athletic trainers are asked to help evaluate the legality, safety, and efficacy of dietary supplements. For this position statement, our mission is to provide the athletic trainer with the necessary resources for these tasks.

Recommendations

Proper nutrition and changes in the athlete''s habitual diet should be considered first when improved performance is the goal. Athletes need to understand the level of regulation (or lack thereof) governing the dietary supplement industry at the international, federal, state, and individual sport-participation levels. Athletes should not assume a product is safe simply because it is marketed over the counter. All products athletes are considering using should be evaluated for purity (ie, truth in labeling), safety, and efficacy.Key Words: ergogenics, Dietary Supplement and Health Education Act, World Anti-Doping AgencyFoods and dietary supplements have been used to enhance health and athletic performance (ergogenics) since the early Olympic Games. Today, athletes at all levels of competition continually work to improve performance, and many consider the use of dietary supplements or engineered foods to gain an additional performance edge or health benefit. This may concern health care professionals because athletes may receive advice and feel pressure from many well-meaning supporters and advocates. However, athletes can be vulnerable to misinformation and risk in terms of the safety, legality, and efficacy of dietary supplements.Although determining overall rates of supplement use among athletes is difficult, estimates of use by collegiate, high school, and middle school athletes have been reported in the literature.16 In a 2004 study by Burns et al,1 88% of the collegiate athletes surveyed used 1 or more nutritional supplements, yet the perceived efficacy of those supplements was only moderate. Athletic trainers (ATs) were their primary sources of nutrition information and were perceived to have significant nutrition knowledge. The 2012 “Substance Use” report compiled by the National Collegiate Athletic Association (NCAA) presented survey data from 20 474 US athletes and compared those data with 2005 outcomes.7 Although survey data are limited by the perceived anonymity of the results, they can be useful to better understand trends and potential risk factors.The overwhelming industry presence and advertising appeal likely has strong influence on athlete choices. According to the 2011 “Sports Nutrition and Weight Loss Report,”8 9% annual sales growth and $22.7 billion in total sales were noted for sports nutrition and weight-loss products in 2010. Energy drinks and shots (small containers of concentrated product) were the primary product category ($12 million) and were purchased through mass channels. A December 2010 press release from the US Food and Drug Administration (FDA) regarding methylhexaneamine, which has been identified as the “new ephedra” (stimulant), anticipated continued reports of adverse events, failed drug tests, and product recalls. The release also cited consumer-trust issues in the supplement industry and the joining of forces by the FDA and major trade organizations to “clean up” the industry. Obviously, health care practitioners need to be aware of the trends in supplement use and the risks the supplements may carry for athletes'' health and sport eligibility.As health care professionals, ATs must be knowledgeable regarding basic nutrition and supplement use and must be able to educate their athletes regarding the efficacy, safety, and legal issues associated with the use of supplements. If they are not knowledgeable in these areas, ATs must be aware of resources for education and proper referral, so they can provide guidance for those within the athletic community. This position statement provides suggested resources to help ATs stay current in the ever-changing landscape of dietary supplements.To formalize the position statement objectives into recommendations, we used (where appropriate) evidence-based review and the Strength of Recommendation Taxonomy (SORT) criterion scale (9 and adopted by the National Athletic Trainers'' Association. Some of the educational materials regarding dietary supplements are found in federal law; these are noted in the recommendations.

Table. Strength of Recommendation Taxonomy (SORT)a

Strength of Recommendation
Definition
ARecommendation based on consistent and good-quality, patient-oriented evidencea
BRecommendation based on inconsistent or limited-quality, experimental evidencea
CRecommendation based on consensus, usual practice, opinion, disease-oriented evidence,b or case series for studies of diagnosis, treatment, prevention, or screening
Open in a separate windowa Reprinted with permission from “Strength of Recommendation Taxonomy (SORT): A Patient-Centered Approach to Grading Evidence in the Medical Literature,” February 1 2004, American Family Physician. Copyright © 2004 American Academy of Family Physicians. All rights reserved.b Patient-oriented evidence measures outcomes that matter to patients: morbidity, mortality, symptom improvement, cost reduction, quality of life. Disease-oriented evidence measures intermediate, physiologic, or surrogate end points that may or may not reflect improvements in patient outcomes (ie, blood pressure, blood chemistry, physiological function, and pathological findings).

Recommendations

Evaluation of the literature associated with performance nutrition and dietary supplements resulted in the following evidence-based recommendations:
  • 1.Performance can be enhanced using an intentional performance diet. When attempting to improve an athlete''s performance, we should consider proper nutrition, and changes in the athlete''s habitual diet should be considered first. The AT should be knowledgeable in the area of performance nutrition and aware of resources for nutritional information. If he or she is not knowledgeable, the AT should establish a support team that includes a registered dietitian or other health care professional with expertise in nutrition.1018 Evidence Category: A.
  • 2.Athletes need to understand the level of regulation (or lack thereof) governing the supplement industry at the international, federal, state, and individual sport-participation levels. Athletes should not assume a product is safe simply because it is marketed over the counter.
    • a.Athletes and ATs should be aware that dietary supplement labels do not require third-party verification; purity (truth in labeling), and noncontamination cannot be assumed.1922 Evidence Category: A.
    • b.All ATs should be prepared to educate athletes that dietary supplements are not well regulated and may contain banned substances. Sport governing bodies provide athletes and other personnel with the rules regarding banned substances and their philosophies regarding supplementation.23,24 Evidence Category: C.
  • 3.Products athletes are considering ingesting should be evaluated for purity (ie, truth in labeling), safety, and efficacy. Current federal law does not require manufacturers or distributors to provide evidence of purity, safety, or efficacy before products are distributed or sold.
    • a.Labeling requirements for dietary supplements are similar to those for food products.22,25 Because ATs cannot be expected to perform a direct analysis of supplement purity, they should be aware of resources to help identify companies or products known to have a history of problems with labeling, adulteration, or contamination. Evidence Category: C.
    • b.Federal regulations do not require supplement manufacturers to provide evidence of safety.22,25 Therefore, ATs should be aware of resources to identify products associated with adverse effects. Athletes should also be educated about the lack of regulation, because they are ultimately responsible for the health and eligibility risks resulting from use.26 Evidence Category: C.
    • c.Dietary supplement manufacturers are not required to provide evidence of efficacy.22,25 As a result, ATs should be aware of resources to identify supplements (or individual components), the quantity of active ingredients, and the mixture of active and inactive ingredients supported by peer-reviewed scientific evidence relating to product efficacy. Evidence Category: C.
  相似文献   
16.
Sawada  Y; Fass  DN; Katzmann  JA; Bahn  RC; Bowie  EJ 《Blood》1986,67(5):1229-1239
Hemostatic plug (HP) formation was investigated in the ear bleeding time incision in normal and von Willebrand pigs. HP volume was calculated by integrating the areas of serial sections. In normal pigs (n = 11), platelets immediately formed a layer on the surface of the cut channel. Platelet aggregates formed at the ends of transected vessels and gradually enlarged. Finally, all transected vessels were occluded by HP and bleeding stopped. In contrast, large HPs were formed in the incision in von Willebrand's disease (vWD) pigs (n = 4); these HPs did not cover the ends of the transected vessels, which continued to bleed, allowing the formation of large hemostatically ineffective platelet aggregates in the incision. Canals traversed these HPs, and bleeding from the open vessels may have continued through them. After infusion of cryoprecipitate into a vWD pig, the bleeding time shortened, and the morphological findings of the HPs were similar to those of normal pigs. In normal pigs (n = 3) infused with an anti- Willebrand factor monoclonal antibody, which prolonged the bleeding time, a large HP formed in the incision, similar to that observed in the vWD pig. The volume of the normal and vWD HPs increased with time. These in vivo findings suggest that Willebrand factor is involved in the localization of the HP to the damaged vessel and may also play a role in platelet-platelet interaction. A computerized morphometric technique was used for measuring the volume of the hemostatic plugs and the distance of sequential points on the perimeter of the HP from the center of selected bleeding vessels.  相似文献   
17.
There is controversy whether simultaneous thyrostatic medication influences the outcome of radioiodine (131I) therapy in Graves' disease by reducing the absorbed energy dose of 131I when delivering a standard dose. We therefore sought to ascertain whether the outcome of ablative 131I therapy is in any way affected by simultaneous thyrostasis (carbimazole) by aiming for a constant absorbed dose of 200-250 Gy. We prospectively studied 207 patients with Graves' disease (106 with and 101 without simultaneous carbimazole at the time of 131I therapy). All patients were reexamined 3, 6, and 12 months after 131I therapy. The 101 nonthyrostatic patients showed a highly significantly greater success rate (93%) than the 106 thyrostatic patients (49%). Stepwise logistic regression demonstrated that failure was related to the administration of carbimazole during 131I therapy (P < 0.00005) and the absorbed dose (P < 0.025), but was not related to free T3, free T4, TSH receptor antibodies, or thyroid volume. The success rate was 100% in 93 nonthyrostatic patients with absorbed doses of 200 Gy or more, but was only 12.5% (1 of 8) for absorbed doses less than 200 Gy. Correlation between success and absorbed dose was significantly higher for nonthyrostatic than for thyrostatic patients (r = 0.93 vs. r = 0.24). Sixteen patients who discontinued thyrostasis 1-3 days before 131I therapy showed 94% successes. Simultaneous thyrostasis is the decisive factor against a successful 131I therapy even if the significantly reduced 131I uptake/half-life values under thyrostasis are compensated with a higher delivered dose to ensure a comparable absorbed dose, possibly due to the additionally effective radioprotective properties of carbimazole. Therefore, if clinically feasible, we recommend discontinuing thyrostasis at least 1 day before beginning 131I therapy, because even in hyperthyroid nonthyrostatic patients the success rate was 100%.  相似文献   
18.
Introduction: Patients presenting with cirrhosis and hepatic tumours represent a fragile group that have typically been avoided in early series of laparoscopic liver resection. This study was undertaken to evaluate the results of a laparoscopic hepatectomy in the setting of cirrhosis.Methods: Subgroup analysis of patients with cirrhosis within a series of 327 patients undergoing a laparoscopic resection was performed. Comparisons were made with patients without cirrhosis where appropriate to highlight differences in patient selection and outcomes. Specific variables assessed included operative details and short-term outcomes including length of stay (LOS), morbidity and mortality. Outcomes specific to hepatocellular carcinoma (HCC) were also assessed.Results: There were 52 patients with cirrhosis undergoing a laparoscopic hepatic resection. Ninety per cent of patients were Childs class A, with a median model for end-stage liver disease (MELD) score of 8. Hepatitis C was the most common cause of cirrhosis (88.5%), whereas the most common indication for an operation was HCC (71.2%). Resections were generally limited, with the median number of segments resected being 2 (range: 1–4). Complications occurred in 13 (25%) patients, with a 90-day mortality of 5.8%. The median LOS was 3 days.Conclusions: A laparoscopic hepatectomy is safe in the setting of cirrhosis, provided the application of appropriate selection criteria and sufficient experience with the procedure.  相似文献   
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