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71.
Summary Considerable disagreement exists regarding the levels of immunoreactive glucose dependent insulinotropic polypeptide in patients with Type 2 (non-insulin-dependent) diabetes mellitus. Glucose dependent insulinotropic polypeptide levels were therefore studied during oral glucose and mixed meal tolerance tests in normal subjects (n=31) and newly presenting previously untreated patients with Type 2 diabetes mellitus (n=68). The tests were performed in random order after overnight fasts and blood samples were taken at 30 min intervals for 4 h. During the oral glucose tolerance test plasma glucose dependent insulinotropic polypeptide levels increased in the normal subjects from a fasting value of 20±3 pmol/l to a peak of 68±5 pmol/l at 30 min and in the Type 2 diabetic patients from a similar fasting level of 27±3 pmol/l to a higher peak value of 104±6 pmol/l at 30 min (p<0.001). Glucose dependent insulinotropic polypeptide levels were significantly higher in the diabetic patients compared with the normal subjects from 30–90 min (p<0.01–0.001) following oral glucose. During the meal tolerance test glucose dependent insulinotropic polypeptide levels increased in the normal subjects from a pre-prandial value of 22±4 pmol/l to a peak of 93±6 pmol/l at 90 min and in the Type 2 diabetic patients from a similar basal level of 25±2 pmol/l to a higher peak of 133±7 pmol/l at 60 min. Glucose dependent insulinotropic polypeptide concentrations were significantly higher in Type 2 diabetic patients compared with the normal subjects at 30 min (p<0.001), 60 min (p<0.01) and from 210–240 min (p<0.05) during the meal tolerance test. The groups were subdivided on the basis of degree of obesity and glucose dependent insulinotropic polypeptide concentrations were still higher in the diabetic subgroups compared with the normal subjects matched for weight. Type 2 diabetes mellitus is associated with an exaggerated glucose dependent insulinotropic polypeptide response to oral glucose and mixed meals which is independent of any effect of obesity.  相似文献   
72.
73.
Factor XIII (FXIII) is necessary for cross linking of fibrin strands and generation of stable fibrin clot. FXIII Val34Leu is a common genetic single nucleotide polymorphism that has been associated with accelerated fibrin stabilization and reduced rate of fibrinolysis. The contribution of Val34Leu to long term risk of recurrent myocardial infarction (MI) in patients with coronary stenting has not been conclusively established. The objective of the study was to examine the effects of Val34Leu on fibrin generation, platelet aggregation, and long term clinical outcomes in patients with coronary artery disease treated with dual antiplatelet therapy. Patients with angiographically documented coronary artery disease who were treated with aspirin and clopidogrel were enrolled (n = 211). Light transmittance aggregometry and plasma fibrin clot formation using thrombelastography (TEG) were determined. Genotyping of Val34Leu was performed using Taqman assay. Clinical events during follow up were recorded. Homozygous carriers of 34Leu variant had significantly shorter fibrin clot formation time as compared to wild type individuals (TEG K: 1.27 ± 0.3 vs. 1.68 ± 1.1 min, p = 0.011). The Val34Leu variant was associated with gene dose dependent increased risk of MI (log rank, p = 0.002) or occurrence of composite of MI and CV death (log rank, p = 0.005) with highest event rates observed in homozygous carriers of 34Leu. In summary, FXIII Val34Leu polymorphism was associated with increased rate of fibrin stabilization in homozygous carriers of the variant and may increase risk of recurrent MI and death in patients with angiographically established coronary artery disease treated with dual antiplatelet therapy.  相似文献   
74.
Microglia most likely appeared early in evolution as they are not only present in vertebrates, but are also found in nervous systems of various nonvertebrate organisms. Mammalian microglia are derived from a specific embryonic, self‐renewable myeloid cell population that is throughout lifetime not replaced by peripheral myeloid cells. These phylogenic and ontogenic features suggest that microglia serve vital functions. Yet, microglia often are described as neurotoxic cells, that actively kill (healthy) neurons. Since it is from an evolutionary point of view difficult to understand why an important and vulnerable organ like the brain should host numerous potential killers, we here review the concept of microglia neurotoxicity. On one hand it is discussed that most of our understanding about how microglia kill neurons is based on in vitro experiments or correlative staining studies that suffer from the difficulty to discriminate microglia and peripheral myeloid cells in the diseased brain. On the other hand it is described that a more functional approach by mutating, inactivating or deleting microglia is seldom associated with a beneficial outcome in an acute injury situation, suggesting that microglia are normally important protective elements in the brain. This might change in chronic disease or the aged brain, where; however, it remains to be established whether microglia simply lose their protective capacities or whether microglia become truly neurotoxic cells. GLIA 2014;62:841–854  相似文献   
75.

Introduction and hypothesis

Stress urinary incontinence (SUI) is a common and growing problem among adult women and affects individuals and society through decreased quality of life (QoL), decreased work productivity, and increased health care costs. A new, nonsurgical treatment option has become available for women who have failed conservative therapy, but its cost effectiveness has not been evaluated. This study examined the cost effectiveness of transurethral radiofrequency microremodeling of the female bladder neck and proximal urethra compared with synthetic transobturator tape (TOT), retropubic transvaginal tape (TVT) sling, and Burch colposuspension surgeries for treating SUI.

Methods

A Markov model was used to compare the cost effectiveness of five strategies for treating SUI for patients who had previously failed conservative therapy. The strategies were designed to compare the value of starting with a less invasive treatment. The cost-effectiveness analysis was conducted from the health care system perspective. Efficacy and adverse event rates were obtained from the literature; reimbursement costs were based on Medicare fee schedule. The model cycle was 3 months, with a 3-year time horizon. Single-variable sensitivity analyses were conducted to assess stability of base-case results.

Results

Two of the five strategies employed the use of transurethral radiofrequency microremodeling and achieved 17–30 % lower mean costs relative to their comparative sling or Burch strategies.

Conclusions

Superior safety and cost effectiveness are recognized when patients are offered a sequential approach to SUI management that employs transurethral radiofrequency microremodeling before invasive surgical procedures. This sequential approach is consistent with treatment strategies for other conditions and offers a solution for women with SUI who want to avoid the inherent risks and costs of invasive continence surgery.  相似文献   
76.

Objective

A suboptimal level of seasonal influenza vaccination among pregnant minority women is an intractable public health problem, requiring effective message resonance with this population. We evaluated the effects of randomized exposure to messages which emphasize positive outcomes of vaccination (“gain-frame”), or messages which emphasize negative outcomes of forgoing vaccination (“loss-frame”). We also assessed multilevel social and community factors that influence maternal immunization among racially and ethnically diverse populations.

Study design

Minority pregnant women in metropolitan Atlanta were enrolled in the longitudinal study and randomized to receive intervention or control messages. A postpartum questionnaire administered 30 days postpartum evaluated immunization outcomes following baseline message exposure among the study population. We evaluated key outcomes using bivariate and multivariate analyses.

Results

Neither gain- [OR = 0.5176, (95% CI: 0.203,1.322)] nor loss-framed [OR = 0.5000, 95% CI: (0.192,1.304)] messages were significantly associated with increased likelihood of immunization during pregnancy. Significant correlates of seasonal influenza immunization during pregnancy included healthcare provider recommendation [OR = 3.934, 95% CI: (1.331,11.627)], use of hospital-based practices as primary source of prenatal care [OR = 2.584, 95% CI: (1.091,6.122)], and perceived interpersonal support for influenza immunization [OR = 3.405, 95% CI: (1.412,8.212)].

Conclusion

Dissemination of vaccine education messages via healthcare providers, and cultivating support from social networks, will improve seasonal influenza immunization among pregnant minority women.  相似文献   
77.
78.
Formulation difficulties prevented the otherwise promising clinical development of the anti-tumour agent trimelamol (TM; tris-[hydroxymethyl]trimethylmelamine). A synthetic analogue programme resulted in the identification of CB 7646 (bis N-[hydroxymethyl]trimethylmelamine) as a compound with improved stability and favourable formulation characteristics. The in vitro and in vivo activity of CB 7646 was shown to be very similar to that of TM. In addition, curative activities were shown in the PXN/65 human ovarian cancer xenograft and the MX-1 and T-61 human breast cancer xenograft models. The effectiveness of the N-(hydroxymethyl)melamines against platinum-refractory disease was noted in the phase I clinical trial of TM. In line with this finding, the present study confirmed the effective activity of both TM and CB 7646 against various forms of platinum resistance in in vitro models. Curative activity for TM and CB 7646 was seen in the HX110P human ovarian cancer xenograft with acquired carboplatin resistance. Animal studies indicated less neurotoxicity for CB 7646 than for TM. The pharmacokinetic profile of CB 7646 indicated a decreased plasma elimination, indicative of slower in vivo degradation than for TM. CB 7646, therefore, represents a promising candidate for clinical development, designed to supersede TM. © 1996 Wiley-Liss, Inc.  相似文献   
79.
ObjectivesDespite advances in understanding associations among attention‐deficit hyperactivity disorder (ADHD), emotion dysregulation (ED), and related outcomes, there is incongruity between ADHD‐relevant conceptualizations of ED and available measures of ED. To assess the psychometric properties of a parent‐report questionnaire of ED conceptualized as deficits in the ability to modulate the (a) speed/degree of emotion escalation; (b) expression intensity; and (c) speed/degree of de‐escalation.MethodsParticipants were 209 adolescents with ADHD (78% male; 13.5–17.8 years old [M = 15.2 SD = 0.91]). Questionnaire items were selected from parent‐report scales of ED and oppositional defiant disorder and subjected to exploratory factor analysis (EFA) and validity analyses.ResultsThe EFA revealed two factors, with speed/degree of escalation combined with intensity as factor one, and speed/degree of de‐escalation as factor two. Factor one scores were related to ADHD impulsivity symptoms but not to anxiety and depression symptoms and they remained predictors of impulsivity even in the presence of self‐report ED, evincing convergent, discriminant, and incremental validity. Factor two scores were related to anxiety and depression but not impulsivity, evincing convergent and discriminant validity.ConclusionThese results inform our understanding of ADHD‐relevant ED in adolescence and offer avenues for future research in measurement development, as well as for understanding ED and ADHD‐related impairment.  相似文献   
80.
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