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41.
M J Otto S Garber D L Winslow C D Reid P Aldrich P K Jadhav C E Patterson C N Hodge Y S Cheng 《Proceedings of the National Academy of Sciences of the United States of America》1993,90(16):7543-7547
Protease inhibitors are another class of compounds for treatment of human immunodeficiency virus (HIV)-caused disease. The emergence of resistance to the current anti-HIV drugs makes the determination of potential resistance to protease inhibitors imperative. Here we describe the isolation of an HIV type 1 (HIV-1) resistant to an HIV-protease inhibitor. Serial passage of HIV-1 (strain RF) in the presence of the inhibitor, [2-pyridylacetylisoleucylphenylalanyl-psi (CHOH)]2 (P9941), failed to yield a stock of virus with a resistance phenotype. However, variants of the virus with 6- to 8-fold reduced sensitivity to P9941 were selected by using a combination of plaque assay and endpoint titration. Genetic analysis and computer modeling of the variant proteases revealed a single change in the codon for amino acid 82 (Val-->Ala), which resulted in a protease with lower affinity and reduced sensitivity to this inhibitor and certain, but not all, related inhibitors. 相似文献
42.
The transmissible spongiform encephalopathy (TSE) diseases are rare, neurodegenerative diseases that include scrapie in sheep, bovine spongiform encephalopathy, and Creutzfeldt-Jakob disease in humans. There are no effective treatments available for clinical use in humans. We now demonstrate that, in 2 different rodent models of scrapie, multiple pretreatments with the cyclic tetrapyrrole phthalocyanine tetrasulfonate (PcTS) were as effective at delaying disease as multiple treatments starting at the time of infection. At low doses of scrapie infectivity, PcTS also protected some mice from peripheral scrapie infection, even if treatment was initiated several weeks after infection. Furthermore, PcTS completely inactivated low levels of scrapie infectivity when incubated with the infectious inoculum. Thus, PcTS has a broad range of antiscrapie activities. These findings suggest that cyclic tetrapyrroles may be useful both prophylactically and therapeutically against TSE diseases in vivo, as well as for inactivation of TSE infectivity suspended in solution. 相似文献
43.
Sudden cardiac death (SCD) is the leading cause of cardiac death in the US. In the past few years, intensive efforts have been made to expand public awareness of SCD and to increase our understanding of its pathophysiology, medical treatment options and device therapy. Significant advances have been made in our ability to prevent SCD in both primary and secondary health care. Two critical issues remain, however: the identification of patients who would benefit from such therapies, and how to achieve even greater prevention, especially primary prevention. The goal of this article is to provide a review of the topic of SCD in the setting of abnormal myocardial substrate, to outline the techniques that are useful in identifying patients at risk, and available treatment options. 相似文献
44.
Janneke AL van Kempen Henk J Schers Anne Jacobs Sytse U Zuidema Franca Ruikes Sarah HM Robben René JF Melis Marcel GM Olde Rikkert 《The British journal of general practice》2013,63(608):e225-e231
Background
Primary care is increasingly interested in the identification of frailty, as it selects the target population for integrated care. However, instruments for the identification of frailty specifically validated for use in primary care are scarce. This study developed the Easycare Two-step Older persons Screening (Easycare-TOS), which provides a valid, efficient, and pragmatic screening procedure to identify frail older people.Aim
This paper aims to describe the development of the Easycare-TOS and the data from the pilot studies.Design and setting
Observational pilot study in seven academic GP practices in and around Nijmegen, The Netherlands.Method
The Easycare-TOS was developed in a cyclic process with the input of stakeholders. In every cycle, the requirements were first defined, then translated into a prototype that was tested in a pilot study. The Easycare-TOS makes optimal use of prior knowledge of the GP, and the professionals’ appraisal is decisive in the frailty decision, instead of a cut-off score. Further, it considers aspects of frailty, as well as aspects of the care context of the patient.Results
The pilot data have shown that after step 1, two-thirds of the patients do not need further assessment, because they are judged as not frail, based on prior knowledge of the GP. The overall prevalence of frailty in this pilot study is 24%. Most professionals who participated in the pilot studies considered the time investment acceptable and the method to be of added value.Conclusion
The Easycare-TOS instrument meets the predefined efficiency, flexibility, and acceptability requirements for use as an identification instrument for frailty in primary care. 相似文献45.
46.
Fosbol EL Wang TY Li S Piccini JP Lopes RD Shah B Mills RM Klaskala W Alexander KP Thomas L Roe MT Peterson ED 《American heart journal》2012,163(4):720-728
47.
Kaitlyn J. Kelly Emily Winslow David Kooby Neha L. Lad Alexander A. Parikh Charles R. Scoggins Syed Ahmad Robert C. Martin Shishir K. Maithel H. J. Kim Nipun B. Merchant Clifford S. Cho Sharon M. Weber 《Journal of gastrointestinal surgery》2013,17(7):1209-1217
Introduction
Current National Comprehensive Cancer Network guidelines recommend neoadjuvant therapy for borderline resectable pancreatic adenocarcinoma to increase the likelihood of achieving R0 resection. A consensus has not been reached on the degree of venous involvement that constitutes borderline resectability. This study compares the outcome of patients who underwent pancreaticoduodenectomy with or without vein resection without neoadjuvant therapy.Methods
A multi-institutional database of patients who underwent pancreaticoduodenectomy was reviewed. Patients who required vein resection due to gross vein involvement by tumor were compared to those without evidence of vein involvement.Results
Of 492 patients undergoing pancreaticoduodenectomy, 70 (14 %) had vein resection and 422 (86 %) did not. There was no difference in R0 resection (66 vs. 75 %, p?=?NS). On multivariate analysis, vein involvement was not predictive of disease-free or overall survival.Conclusion
This is the largest modern series examining patients with or without isolated vein involvement by pancreas cancer, none of whom received neoadjuvant therapy. Oncological outcome was not different between the two groups. These data suggest that up-front surgical resection is an appropriate option and call into question the inclusion of isolated vein involvement in the definition of “borderline resectable disease.” 相似文献48.
Smoking cessation is associated with improved survival in oropharynx cancer treated by chemoradiation
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Alexis J. Platek BSc Vijayvel Jayaprakash MBBS PhD Mihai Merzianu MD Mary E. Platek PhD David M. Cohan MD Wesley L. Hicks MD Jr. Sathiya P. Marimuthu MBBS Timothy B. Winslow MS Vishal Gupta MD Hassan Arshad MD Moni A. Kuriakose MD Shiva Dibaj MS James R. Marshall PhD Mary E. Reid PhD Graham W. Warren MD PhD Anurag K. Singh MD 《The Laryngoscope》2016,126(12):2733-2738
49.
Alexandra?W.?Acher Malcolm?H.?Squires Ryan?C.?Fields George?A.?Poultsides Carl?Schmidt Konstantinos?I.?Votanopoulos Timothy?M.?Pawlik Linda?X.?Jin Aslam?Ejaz David?A.?Kooby Mark?Bloomston David?Worhunsky Edward?A.?Levine Neil?Saunders Emily?Winslow Clifford?S.?Cho Glen?Leverson Shishir?K.?Maithel Sharon?M.?WeberEmail author 《Journal of gastrointestinal surgery》2016,20(7):1284-1294
Background
This study utilized a multi-institutional database to evaluate risk factors for readmission in patients undergoing curative gastrectomy for gastric adenocarcinoma with the intent of describing both perioperative risk factors and the relationship of readmission to survival.Methods
Patients who underwent curative resection of gastric adenocarcinoma from 2000 to 2012 from seven academic institutions of the US Gastric Cancer Collaborative were analyzed. In-hospital deaths and palliative surgeries were excluded, and readmission was defined as within 30 days of discharge. Univariate and multivariable logistic regression analyses were employed and survival analysis conducted.Results
Of the 855 patients, 121 patients (14.2 %) were readmitted. Univariate analysis identified advanced age (p?<?0.0128), American Society of Anesthesiology status ≥3 (p?=?0.0045), preexisting cardiac disease (p?<?0.0001), hypertension (p?=?0.0142), history of smoking (p?=?0.0254), increased preoperative blood urea nitrogen (BUN; p?=?0.0426), concomitant pancreatectomy (p?=?0.0056), increased operation time (p?=?0.0384), estimated blood loss (p?=?0.0196), 25th percentile length of stay (<7 days, p?=?0.0166), 75th percentile length of stay (>12 days, p?=?0.0256), postoperative complication (p?<?0.0001), and total gastrectomy (p?=?0.0167) as risk factors for readmission. Multivariable analysis identified cardiac disease (odds ratio (OR) 2.4, 95 % confidence interval (CI) 1.6–3.3, p?<?0.0001), postoperative complication (OR 2.3, 95 % CI 1.6–5.4, p?<?0.0001), and pancreatectomy (OR 2.2, 95 % CI 1.1–4.1, p?=?0.0202) as independent risk factors for readmission. There was an association of decreased overall median survival in readmitted patients (39 months for readmitted vs. 103 months for non-readmitted). This was due to decreased survival in readmitted stage 1 (p?=?0.0039), while there was no difference in survival for other stages. Stage I readmitted patients had a higher incidence of cardiac disease than stage I non-readmitted patients (58 vs. 24 %, respectively, p?=?0.0002).Conclusions
Within this multi-institutional study investigating readmission in patients undergoing curative resection for gastric cancer, cardiac disease, postoperative complication, and concomitant pancreatectomy were identified as significant risk factors for readmission. Readmission was associated with decreased overall median survival, but on further analysis, this was driven by differences in survival for stage I disease only.50.
Methamphetamine is a stimulant commonly abused in many parts of the United States. Most methamphetamine users are white men 18 to 25 years of age, but the highest usage rates have been found in native Hawaiians, persons of more than one race, Native Americans, and men who have sex with men. Methamphetamine use produces a rapid, pleasurable rush followed by euphoria, heightened attention, and increased energy. Possible adverse effects include myocardial infarction, stroke, seizures, rhabdomyolysis, cardiomyopathy, psychosis, and death. Chronic methamphetamine use is associated with neurologic and psychiatric symptoms and changes in physical appearance. High-risk sexual activity and transmission of human immunodeficiency virus are also associated with methamphetamine use. Use of methamphetamine in women who are pregnant can cause placental abruption, intrauterine growth retardation, and preterm birth, and there can be adverse consequences in children exposed to the drug. Treatment of methamphetamine intoxication is primarily supportive. Treatment of methamphetamine abuse is behavioral; cognitive behavior therapy, contingency management, and the Matrix Model may be effective. Pharmacologic treatments are under investigation. 相似文献