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71.
BACKGROUND: Since the advent of direct-to-consumer (DTC) advertising in the 1980s, there have been numerous studies and surveys on the topic, addressing issues as varied as its impact on patient understanding of health conditions to its repercussions for drug spending. However, until 2001, there was a dearth of research on DTC advertising's impact on minority populations, specifically the African-American community. The National Medical Association (NMA) remedied that in 2001 by undertaking a landmark study that gauged African-American physicians' perceptions of DTC advertising, its impact on the doctor-patient relationship and, perhaps most importantly, its role in educating underserved populations about critical health issues and potential treatments. In 2006, the NMA decided to once again poll its members on this critical issue to gauge not only current perceptions but how the community's understanding of DTC advertising has changed since 2001. RESULTS: The 2006 survey revealed several clear trends: NMA physicians are more positive toward DTC advertising now than they were in 2001; African-American physicians see DTC advertising as providing substantial educational benefits; physicians believe that DTC advertising helps rather than hurts the doctor-patient relationship; and African-American physicians see the benefits of DTC advertising outweighing its drawbacks. It must be noted that NMA physicians also had clear concerns about DTC advertising that point to potential areas of improvement for pharmaceutical companies.  相似文献   
72.
Objective: Few data are available on the Italian elderly population with regard to adherence to the Mediterranean diet (MD) and cognitive impairment. Our aim was to investigate adherence to the MD and its association with cognitive function in an Italian urban sample.

Methods: A cross-sectional study of 279 participants aged ≥ 65 years (80 men, 199 women) was carried out at a nutritional center. Adherence to the MD was evaluated using a 14-item questionnaire. Cognitive function was assessed with the Mini-Mental State Examination (MMSE).

Results: The clinical and nutritional assessments performed revealed 30.1% to have a dietary pattern in accordance with the MD; 13.6% had suspected or mild cognitive impairment (MMSE score ≤ 23). The MD pattern was associated with a lower risk of cognitive impairment (odds ratio [OR] = 0.39; 95% confidence interval [CI], 0.15–0.99; p = 0.045), as was the consumption of wine (OR = 0.37; 95% CI, 0.16–0.84; p = 0.018) and nuts (OR = 0.30; 95% CI, 0.13–0.69, p = 0.005). No association was found with other food groups.

Conclusion: A closer adherence to the MD was associated with a better cognitive status. Further cohort studies and randomized controlled trials are warranted.  相似文献   

73.
Porcine reproductive and respiratory syndrome virus (PRRSV) is prevalent in Danish swine herds. In July 2019, PRRSV‐1 was detected in a PRRSV‐negative boar station and subsequently spread to more than 38 herds that had received semen from the boar station. Full genome sequencing revealed a sequence of 15.098 nucleotides. Phylogenetic analyses showed that the strain was a recombination between the Amervac strain (Unistrain PRRS vaccine; Hipra) and the 96V198 strain (Suvaxyn PRRS; Zoetis AH). The major parent was the 96V198 strain that spanned ORFs 1–2 and part of ORF 3 and the minor parent was the Amervac strain, which constituted the remaining part of the genome. The virus seems to be highly transmissible and has caused severe disease in infected herds despite a high level of genetic identity to the attenuated parent strains. The source of infection was presumable a neighbouring farm situated 5.8 km from the boar station.  相似文献   
74.
75.
Activation of G protein-coupled receptors involves major conformational changes of the receptor protein ranging from the extracellular transmitter binding site to the intracellular G protein binding surface. GPCRs such as the muscarinic acetylcholine receptors are commonly probed with radioantagonists rather than radioagonists due to better physicochemical stability, higher affinity, and indifference towards receptor coupling states of the former. Here we introduce tritiated iperoxo, a superagonist at muscarinic M2 receptors with very high affinity. In membrane suspensions of transfected CHO-cells, [3H]iperoxo – unlike the common radioagonists [3H]acetylcholine and [3H]oxotremorine M – allowed labelling of each of the five muscarinic receptor subtypes in radioagonist displacement and saturation binding studies. [3H]iperoxo revealed considerable differences in affinity between the even- and the odd-numbered muscarinic receptor subtypes with affinities for the M2 and M4 receptor in the picomolar range. Probing ternary complex formation on the M2 receptor, [3H]iperoxo dissociation was not influenced by an archetypal allosteric inverse agonist, reflecting activation-related rearrangement of the extracellular loop region. At the inner side of M2, the preferred Gi protein acted as a positive allosteric modulator of [3H]iperoxo binding, whereas Gs and Gq were neutral in spite of their robust coupling to the activated receptor. In intact CHO-hM2 cells, endogenous guanylnucleotides promoted receptor/G protein-dissociation resulting in low-affinity agonist binding which, nevertheless, was still reported by [3H]iperoxo. Taken together, the muscarinic superagonist [3H]iperoxo is the best tool currently available for direct probing activation-related conformational transitions of muscarinic receptors.  相似文献   
76.
This work evaluates the dry sliding behavior of anodic aluminum oxides (AAO) formed during one traditional hard anodizing treatment (HA) and two golden hard anodizing treatments (named G and GP, respectively) on a EN AW-6060 aluminum alloy. Three different thicknesses of AAO layers were selected: 25, 50, and 100 μm. Prior to wear tests, microstructure and mechanical properties were determined by scanning electron microscopy (VPSEM/EDS), X-ray diffractometry, diffuse reflectance infrared Fourier transform (DRIFT-FTIR) spectroscopy, roughness, microhardness, and scratch tests. Wear tests were carried out by a pin-on-disc tribometer using a steel disc as the counterpart material. The friction coefficient was provided by the equipment. Anodized pins were weighed before and after tests to assess the wear rate. Worn surfaces were analyzed by VPSEM/EDS and DRITF-FTIR. Based on the results, the GP-treated surfaces with a thickness of 50 μm exhibit the lowest friction coefficients and wear rates. In any case, a tribofilm is observed on the wear tracks. During sliding, its detachment leads to delamination of the underlying anodic aluminum oxides and to abrasion of the aluminum substrate. Finally, the best tribological performance of G- and GP-treated surfaces may be related to the existence of a thin Ag-rich film at the coating/aluminum substrate interfaces.  相似文献   
77.
Since late 2020, outbreaks of H5 highly pathogenic avian influenza (HPAI) viruses belonging to clade 2.3.4.4b have emerged in Europe. To investigate the evolutionary history of these viruses, we performed genetic characterization on the first HPAI viruses found in Denmark during the autumn of 2020. H5N8 viruses from 14 wild birds and poultry, as well as one H5N5 virus from a wild bird, were characterized by whole genome sequencing and phylogenetic analysis. The Danish H5N8 viruses were found to be genetically similar to each other and to contemporary European clade 2.3.4.4b H5N8 viruses, while the Danish H5N5 virus was shown to be a unique genotype from the H5N5 viruses that circulated at the same time in Russia, Germany, and Belgium. Genetic analyses of one of the H5N8 viruses revealed the presence of a substitution (PB2-M64T) that is highly conserved in human seasonal influenza A viruses. Our analyses showed that the late 2020 clade 2.3.4.4b HPAI H5N8 viruses were most likely new incursions introduced by migrating birds to overwintering sites in Europe, rather than the result of continued circulation of H5N8 viruses from previous introductions to Europe in 2016/2017 and early 2020.  相似文献   
78.
79.
The authors investigated AIDS-related knowledge, high-risk behaviors, and relationships between AIDS-related knowledge, high-risk behaviors, and sociodemographic characteristics of 41 pregnant women entering treatment who were dependent on cocaine or opiates. At entry, patients completed self-report questionnaires on AIDS-related knowledge and sexual and drug use practices. There was a high rate of understanding of risk associated with drug use and perinatal transmission of HIV. Knowledge of high-risk sexual behavior varied, and knowledge of the medical consequences of HIV was modest. Engagement in several high-risk behaviors was identified: lack of condom use, intravenous drug use, sharing of needles, sex with an injecting drug user, and exchanging sex for money or drugs. AIDS-related knowledge and engagement in high-risk behaviors were not significantly correlated. Authors discussed implications of these findings for developing effective HIV prevention strategies in this population. (American Journal on Addictions 1996; 5:292–300)  相似文献   
80.
PURPOSE: 6-Mercaptopurine (6-MP) has proven efficacy in the therapy of inflammatory bowel disease. Its teratogenicity is demonstrated in animal studies when used at very high doses, whereas human data suggest that 6-MP at maintenance doses is safe. We report the outcome of 72 pregnancies in patients with inflammatory bowel disease who were previously treated with 6-MP with three different doses of 50, 75, and 100 mg/d, for a median duration of 18 months, along with long-term follow-up of the children. METHODS: We have compared the outcome of pregnancies and development of the offspring in the following two groups: group 1, patients with inflammatory bowel disease who conceived 6 months to 22 years after stopping 6-MP (median 72 months); and group 2, patients with inflammatory bowel disease who never received 6-MP prior to conception. All pregnancies were evaluated in terms of outcome: live full-term birth, premature delivery, stillbirth, spontaneous abortion, ectopic pregnancy, and therapeutic dilatation and curettage. Data on children were obtained regarding birth weight, congenital anomalies, and development. RESULTS: Group 1 included 72 pregnancies carried by 29 women. There were 51 live births (4 premature), 16 spontaneous abortions, 1 stillbirth, 2 therapeutic abortions due to abnormal amniocentesis, and 2 ectopic pregnancies. The total incidence of fetal loss was 29.2%. In group 2, 75 women had 140 pregnancies resulting in 120 live births (8 premature), 18 spontaneous abortions, and 2 stillbirths. There were no cases of ectopic pregnancies or abnormal amniocentesis. The total incidence of fetal loss was 14.3%. There was no increase in the incidence of developmental defects when the mothers had been treated with 6-MP prior to pregnancy. CONCLUSIONS: The incidence of fetal loss is higher in women with inflammatory bowel disease who had been previously treated with 6-MP compared with those who had not. Whether this was related to the older age at conception in 6-MP group, longer duration of disease, initially more severe disease, or use of 6-MP we cannot tell.  相似文献   
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