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61.
62.
BackgroundTobacco smoking is the leading cause of preventable deaths worldwide, but many smokers are simply unable to quit. Psychosocial and pharmaceutical treatments have shown modest results on smoking cessation rates, but there is an urgent need to develop treatments with greater efficacy. Brain stimulation methods are gaining increasing interest as possible addiction therapeutics.ObjectivesThe purpose of this paper is to review the studies that have evaluated brain stimulation techniques on tobacco addiction, and discuss future directions for research in this novel area of addiction interventions.MethodsElectronic and manual literature searches identified fifteen studies that administered repetitive transcranial magnetic stimulation (rTMS), cranial electrostimulation (CES), transcranial direct current stimulation (tDCS) or deep brain stimulation (DBS).ResultsrTMS was found to be the most well studied method with respect to tobacco addiction. Results indicate that rTMS and tDCS targeted to the dorsolateral prefrontal cortex (DLPFC) were the most efficacious in reducing tobacco cravings, an effect that may be mediated through the brain reward system involved in tobacco addiction. While rTMS was shown to reduce consumption of cigarettes, as yet no brain stimulation technique has been shown to significantly increase abstinence rates. It is possible that the therapeutic effects of rTMS and tDCS may be improved by optimization of stimulation parameters and increasing the duration of treatment.ConclusionAlthough further studies are needed to confirm the ability of brain stimulation methods to treat tobacco addiction, this review indicates that rTMS and tDCS both represent potentially novel treatment modalities.  相似文献   
63.
The authors describe two siblings, each with a different, rare genetic condition that affects liver function. The index case, the 18-year-old asymptomatic brother of a young man recently diagnosed with Wilson disease, presented for Wilson disease screening and was also found to have abnormal liver function suggestive of cholestasis. However, ceruloplasmin level, 24 h urine copper concentration and liver synthetic function were normal. Further hepatic investigations and genetic mutation analysis were performed, ultimately leading to a diagnosis of Alagille syndrome. He was treated with ursodiol, which resulted in normalization of his liver function tests. Subsequently, he was found to be a carrier for a mutation in the Wilson disease gene, ATP7B. In the present report, the potential implications of being a heterozygote for Wilson disease in the context of Alagille syndrome are discussed. Also stressed is that care must be exercised by the clinician when diagnosing family members who may present with two different disorders closely mimicking one another.  相似文献   
64.
Patients suffering major traumatic or surgical bleeding are often exposed to hemodilution resulting in dilutional coagulopathy. The aim of this study was to evaluate in vitro the effects of fibrinogen, factor XIII and thrombin-activatable fibrinolysis inhibitor (TAFI) on clot formation and resistance to fibrinolysis in hemodilution conditions. Citrated whole blood from 36 healthy volunteers was diluted to 30 and 60% with lactated Ringer's solution. Blood samples were subsequently supplemented with fibrinogen, FXIII, TAFI or their combinations. Rotation thromboelastometry (ROTEM) in whole blood and thrombin generation in plasma were performed in the presence of CaCl? and tissue factor/EXTEM reagent, and fibrinolysis was induced by tissue plasminogen activator (tPA). Hemodilution was expressed by decrease of peak height in thrombin generation and α-angle and maximum clot firmness (MCF) in ROTEM. Fibrinogen, FXIII or TAFI did not correct the decrease in thrombin generation peak height. In ROTEM, spiking of diluted blood with fibrinogen stimulated clot propagation. In tPA-treated blood fibrinogen, FXIII and TAFI increased clot firmness and inhibited fibrinolysis. Stronger protection against fibrinolysis was achieved combining FXIII with TAFI. Hemodilution was associated with inhibition of thrombin generation; however, this effect was not sensitive to blood spiking with fibrinogen, FXIII and TAFI. In ROTEM, these hemostasis agents improved clot strength and decreased clot susceptibility to tPA in nondiluted and to more extent in diluted blood. The maximal protection against fibrinolysis was caused by TAFI. Combining FXIII with TAFI exerted synergistic inhibitory effect on fibrinolysis.  相似文献   
65.
Although inflammation is a physiologic response designed to protect us from infection, when unchecked and ongoing it may cause substantial harm. Both chronic heart failure (CHF) and chronic kidney disease (CKD) are known to cause elaboration of several pro-inflammatory mediators that can be detected at high concentrations in the tissues and blood stream. The biologic sources driving this chronic inflammatory state in CHF and CKD are not fully established. Traditional sources of inflammation include the heart and the kidneys which produce a wide range of pro-inflammatory cytokines in response to neurohormones and sympathetic activation. However, growing evidence suggests that non-traditional biomechanical mechanisms such as venous and tissue congestion due to volume overload are also important as they stimulate endotoxin absorption from the bowel and peripheral synthesis and release of pro-inflammatory mediators. Both during the chronic phase and, more rapidly, during acute exacerbations of CHF and CKD, inflammation and congestion appear to amplify each other resulting in a downward spiral of worsening cardiac, vascular, and renal functions that may negatively impact patients’ outcome. Anti-inflammatory treatment strategies aimed at attenuating end organ damage and improving clinical prognosis in the cardiorenal syndrome have been disappointing to date. A new therapeutic paradigm may be needed, which involves different anti-inflammatory strategies for individual etiologies and stages of CHF and CKD. It may also include specific (short-term) anti-inflammatory treatments that counteract inflammation during the unsettled phases of clinical decompensation. Finally, it will require greater focus on volume overload as an increasingly significant source of systemic inflammation in the cardiorenal syndrome.  相似文献   
66.

Background

Graft pseudoaneurysm (PSA) following pancreatic transplantation (PT) is a rarely reported complication that has significant morbidity and mortality. Few case reports and small series of this complication exist.

Methods

Retrospective review of files of 106 patients who underwent PT at the Tel-Aviv Sourasky Medical center between 1995 and 2010. Accessible asymptomatic patients (n = 35) were referred for graft PSA screening using ultrasound-Doppler.

Results

Eight patients developed graft PSA (8 %). All had early posttransplant sepsis. PSA incidence among patients who had perioperative sepsis is 13 %. Three patients developed early postoperative PSA, presenting as massive abdominal bleeding requiring urgent laparotomy and graft resection. Five patients were diagnosed with late-onset graft PSA between 3 months and 11 years posttransplant: clinical presentations were massive gastrointestinal bleeding (n = 2), acute renal failure (n = 1), and asymptomatic finding on screening ultrasound-Doppler (n = 2, 6 % of screened patients).

Conclusions

PSA following PT occurs in 8 % of patients. Perioperative infection is a risk factor. Early PSAs present as massive intra-abdominal bleeding. PSA may develop years posttransplant, may be asymptomatic, but late rupture is possible and presents as gastrointestinal bleeding. We recommend screening of patients at risk with ultrasound Doppler for early detection and treatment of asymptomatic PSAs.  相似文献   
67.

Background

A grading system for postoperative complications is important for quality control and comparison among investigations. The objective of the current study was to evaluate complications associated with laparoscopic colorectal surgery according to a standardized grading system, and to examine risk factors associated with different complication grades.

Methods

Data of all patients who underwent elective laparoscopic colorectal surgery at two medical centers between September 2003 and January 2011 were collected prospectively. Complications were graded retrospectively into five categories based on a previously proposed grading system for colorectal operations. Age, gender, BMI, Charlson comorbidity score, indication for surgery, pathology site, conversion rate, learning curve, operative times, previous abdominal surgery, concurrent surgical procedures performed, and length of hospital stay were evaluated as risk factors and outcome measures for complications.

Results

A total of 501 patients were included in the study. Of them, 30.5 % suffered at least one complication and 6.5 % more than one. Complications that were mainly medical or surgical site infections requiring minor intervention (grades 1 and 2) occurred in 22.9 % of patients. Surgical complications requiring invasive interference (grades 3 and 4) occurred in 7.4 % of patients and mortality (grade 5) occurred in 0.2 % (1 patient). Length of hospital stay was directly related to complication grade. Average hospital stay was 6.8 ± 3.5, 10.5 ± 5.1, and 20.2 ± 12.3 days for patients with no complications, grade 1–2 complications, and grade 3–4 complications, respectively (p < 0.01). Minor complications (grades 1–2) were associated with conversion (p < 0.01), high Charlson score (p = 0.004), and additional surgical procedures (p = 0.04). Major complications (grades 3–4) were associated solely with conversion (p < 0.01) and rectal pathology (p < 0.01).

Conclusion

This study demonstrates the use of a uniform grading system for complications in laparoscopic colorectal surgery. Conversion was found to be associated with all grades of complications.  相似文献   
68.

Purpose

Bevacizumab has been shown to increase progression free and overall survival in patients with metastatic colorectal cancer. Neoadjuvant bevacizumab is commonly used in patients undergoing liver resection. Our purpose was to evaluate whether bevacizumab is associated with increased rate of perioperative complications in patients undergoing hepatic resection for colorectal liver metastases (CRLM).

Methods

Retrospective analysis of patients undergoing hepatic resection for CRLM who received chemotherapy and bevacizumab (group 1, n?=?134), or chemotherapy alone (group 2, n?=?57). We compared demographics, surgical characteristics, and perioperative course.

Results

Perioperative complications developed in 35 % of patients in group 1, and 47 % in group 2 (p?=?0.11). Of those complications, 15 (11.2 %) in group 1, and 5 (8.8 %) in group 2 were considered major (p?=?0.617). Four patients, all of whom received preoperative bevacizumab, developed enteric leaks following combined liver and bowel resection. The rate of anastomotic leak in group 1 was 10 %, compared with 0 in group 2, p?=?0.56.

Conclusion

Neoadjuvant chemotherapy along with bevacizumab was not associated with an increased risk of postoperative complications after hepatic resection. Possible association of increased morbidity with simultaneous bowel and liver resections following bevacizumab administration was found and we recommend avoiding such treatment combination.  相似文献   
69.
Patients with Parkinson's disease (PD) who carry the G2019S mutation (a glycine to serine substitution at amino acid 2019) in the leucine‐rich repeat kinase 2 (LRRK2) gene are generally believed to be clinically indistinguishable from patients with sporadic PD. There are, however, conflicting reports on the relationship between the mutation and the motor phenotype. We quantitatively compared gait and mobility in patients with PD carriers of the G2019S mutation to non‐carrier patients with PD to better understand the genotype‐phenotype relationship. Fifty patients with PD carriers of the G2019S LRRK2 mutation and 50 age, disease duration, and disease severity matched PD non‐carriers were studied. An accelerometer quantified gait under three walking conditions: usual‐walking, dual‐tasking, and fast‐walking. The Unified Parkinson's Disease Rating Scale classified patients into PD sub‐types and the Timed Up and Go quantified mobility and fall risk. In all three walking conditions, gait variability was larger and the walking pattern was less consistent among the PD mutation carriers (P < 0.016). The PD carriers also took longer to complete the Timed Up and Go (P = 0.011) and were more likely to report having fallen in the previous year (P = 0.018). 64% of the PD carriers were classified as belonging to the postural‐instability‐gait‐difficulty (PIGD) sub‐type compared to only 17% of the PD non‐carriers (P < 0.0001). Among patients with PD, the G2019S mutation in the LRRK2 gene is apparently associated with increased gait variability, an increased fall risk, and the PIGD sub‐type. Therapeutic approach specifically designed to delay gait disturbances and falls may be justified in patients who carry the G2019S mutation. © 2013 International Parkinson and Movement Disorder Society  相似文献   
70.
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