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71.
72.
A human O6-alkylguanine-DNA-alkyltransferase (ATase) cDNA-containing retrovirus was used to infect murine long-term primary bone marrow cultures. High levels of ATase expression were obtained, and colony- forming cells of the granulocyte-macrophage lineage from the cultures transduced with the human ATase retrovirus were three times more resistant to the alkylating agent, N-methyl-N-nitrosourea (MNU), than control cultures. Furthermore, expression of the human ATase protected long-term hematopoiesis, measured as the output of progenitor cells to the nonadherent fraction of the culture, against the cytotoxic effects of repeated exposures to MNU. These results clearly show that a human ATase cDNA-containing retrovirus can be used to infect long-term primary bone marrow cultures and that this attenuates their sensitivity to nitrosoureas.  相似文献   
73.
74.
Summary The hypothesis was tested that islet autoimmunity is induced by ongoing islet cell destruction in subjects with susceptibility genes HLA-DR 3 and/or DR 4. Sixty-one patients with confirmed chronic pancreatitis were analysed, 30 of whom expressed HLA-DR 3 and/or DR 4. Electron microscopy studies in 10 patients showed that the inflammatory process also affected islets, as recognisable from islet cell lysis, intrainsular fibrosis and immune cell infiltrates. None of the sera tested contained any of three markers of islet autoimmunity, ICA, IAA or GAD antibodies. A correlation was seen between the loss of exocrine function, as determined by the ALTAB-test, and of beta-cell function, as determined by the C-peptide response to i. v. glucagon. However, there was no preferential loss of beta-cell function in patients with HLA-DR 3 and/or DR 4. We conclude that islet cell destruction occurs during chronic pancreatitis, but does not trigger islet autoimmunity, even in the presence of HLA-DR 3 and/or DR 4. [Diabetologia (1994) 37: 471–475] Received: 18 August 1993 and in revised form: 17 November 1993  相似文献   
75.
OBJECTIVES: Although informed consent is an issue in many medical malpractice claims, there is no standardized time or method to obtain informed consent for endoscopic procedures. The objectives of this study were to determine whether sedation for endoscopic procedures interfered with pre-endoscopic informed consent and to determine the appropriate time to obtain informed consent. METHODS: Patients undergoing a sedated esophagogastroduodenoscopy had informed consent obtained either 48-72 h before the procedure (group 1A, n = 50) or 10-60 min before the procedure (group 1B, n = 50). Patients undergoing an unsedated flexible sigmoidoscopy had informed consent obtained either 48-72 h before (group 2A, n = 47) or 10-60 min before the procedure (group 2B, n = 49). Methods of informed consent consisted of an oral and a written explanation about the procedure. Patients were sedated with midazolam and meperidine. A Trieger test evaluated recovery from sedation. Recall was assessed by asking six questions about the procedure before discharge and again 2-3 days later. RESULTS: Standard t tests and Mann-Whitney U nonparametric rank tests were used to compare the 1) 1-h recall scores, 2) 2-3-day recall scores, and 3) recall difference scores for groups 1A and 1B, 1A and 2A, 2A and 2B, and 1B and 2B. There were no differences in recall for the different groups. CONCLUSIONS: This study shows that sedation for endoscopic procedures does not interfere with pre-endoscopic informed consent. Informed consent for endoscopic procedures can be obtained at any time before sedation with similar recall.  相似文献   
76.

Objective

The objective was to describe the implementation, work flow, and differences in outcomes between a pharmacist‐managed clinic for the outpatient treatment of venous thromboembolism (VTE) using a non‐vitamin K oral anticoagulant versus care by a primary care provider (PCP).

Methods

Patients in the studied health system that are diagnosed with low‐risk VTE in the emergency department are often discharged without hospital admission. These patients are treated with a non‐vitamin K oral anticoagulant and follow‐up either in a pharmacist‐managed VTE clinic or with their PCP. Pharmacists in the VTE clinic work independently under a collaborative practice agreement (CPA). An evaluation of 34 patients, 17 in each treatment arm, was conducted to compare the differences in treatment‐related outcomes of rivaroxaban when managed by a pharmacist versus a PCP.

Results

The primary endpoint was a 6‐month composite of anticoagulation treatment‐related complications that included a diagnosis of major bleeding, recurrent thromboembolism, or fatality due to either major bleeding or recurrent thromboembolism. Secondary endpoints included number of hospitalizations, adverse events, and medication adherence. There was no difference in the primary endpoint between groups with one occurrence of the composite endpoint in each treatment arm (p = 1.000), both of which were recurrent thromboembolic events. Medication adherence assessment was formally performed in eight patients in the pharmacist group versus no patients in the control group. No differences were seen among other secondary endpoints.

Conclusions

The pharmacist‐managed clinic is a novel expansion of clinical pharmacy services that treats patients with low‐risk VTEs with rivaroxaban in the outpatient setting. The evaluation of outcomes provides support that pharmacist‐managed care utilizing standardized protocols under a CPA may be as safe as care by a PCP.
  相似文献   
77.
Recent developments in the study of the structure and function of opioid receptors raise significant challenges for the definition of individual receptor types and the development of a nomenclature that precisely describes isoforms that may subserve different functions in vivo. Presentations at the 2013 meeting of the International Narcotics Research Conference in Cairns, Australia, considered some of the new discoveries that are now unravelling the complexities of opioid receptor signalling. Variable processing of opioid receptor messenger RNAs may lead to the presence of several isoforms of the μ receptor. Each opioid receptor type can function either as a monomer or as part of a homo- or heterodimer or higher multimer. Additionally, recent evidence points to the existence of agonist bias in the signal transduction pathways activated through μ receptors, and to the presence of regulatory allosteric sites on the receptors. This brief review summarizes the recent discoveries that raise challenges for receptor definition and the characterization of signal transduction pathways activated by specific receptor forms.

LINKED ARTICLES

This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2  相似文献   
78.
Purpose

While low density lipoprotein cholesterol (LDL-C) remains a key contributor of atherosclerotic cardiovascular disease (ASCVD), additional risk factors identified through epidemiological and genetic studies have ushered in a fertile era of drug discovery in lipid-lowering therapy. Unlike contemporary small molecule medications, many of the novel agents are biologics utilizing monoclonal antibody (mAb) or RNA interference (RNAi) technologies. This report aims to review the evidence to date, focusing on completed and ongoing clinical trials and how these new agents will impact clinical practice.

Methods

We review data from pertinent studies on lipid-lowering biologics in clinical use or have translated to human studies and are undergoing clinical trials.

Results

Several targets affecting lipid metabolism have been identified to be causally associated with ASCVD including proprotein convertase subtilisin/kexin type 9 (PCSK9), angiopoietin-like protein 3 (ANGPTL3), apolipoprotein C3 (APOC3), and lipoprotein (a) (Lp[a]). Biotechnological modalities that have been developed for these targets include mAb, small interfering RNA (siRNA), and anti-sense oligonucleotide (ASO) agents. Agents such as alirocumab and evolocumab have shown efficacy in risk reduction of ASCVD in cardiovascular outcome trials and have been incorporated into evidence-based practice guidelines. Other agents included in this review are in various stages of clinical trials and have shown significant efficacy in the reduction of lipid parameters.

Conclusion

The development of new biologics targeting lipid risk factors will provide clinicians additional tools to reduce the risk for ASCVD. Important factors to consider will be cost-effectiveness and improving methods to personalize treatments to risk factors.

  相似文献   
79.
The risk of type 2 diabetes mellitus (T2DM) varies by ethnicity, but ethnic differences in response to diabetes prevention interventions remain unclear. This systematic review and meta-analysis assessed ethnic differences in the effects of lifestyle interventions on T2DM incidence, glycemic outcomes (fasting glucose, 2-h glucose, HbA1c), anthropometric measures (weight, BMI, waist circumference), and lifestyle behaviors (physical activity, energy intake, energy from fat, fiber intake). MEDLINE, EMBASE, and other databases were searched (to June 15, 2020) for randomized and non-randomized controlled trials on lifestyle interventions (diet and/or physical activity) in adults at risk of T2DM. Ethnicity was categorized into European, South Asian, East and Southeast Asian, Middle Eastern, Latin American, and African groups. Forty-four studies were included in meta-analyses. Overall, lifestyle interventions resulted in significant improvement in T2DM incidence, glycemic outcomes, anthropometric measures, physical activity, and energy intake (all P < 0.01). Significant subgroup differences by ethnicity were found for 2-h glucose, weight, BMI, and waist circumference (all P < 0.05) but not for T2DM incidence, fasting glucose, HbA1c, and physical activity (all P > 0.05). Few studies in non-European groups reported dietary intake. Lifestyle interventions in different ethnic groups may have similar effects in reducing incidence of T2DM although this needs to be confirmed in further studies.  相似文献   
80.
Because no accurate and readily applied method exists for continuous recording of left ventricular cavity dimensions and wall motion in man, we designed a catheter-mounted echocardiographic probe. The purpose of this report is to describe the instrumentation, technique, limitations, complications and preliminary observations employing the probe in humans. The echo transducer built into a cardiac allowed positioning in the right heart under fluoroscopy. The echo signals permitted continuous left ventricular cavity measurements at rest and during maneuvers. Our results suggest that intracardiac echo may be able to provide clear definition of motion patterns of the mitral valve and left ventricular walls. The ultrasonic catheter is an instrument that potentially offers a new technique for continuous monitoring of left ventricular size and motion.  相似文献   
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