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991.
BACKGROUND: Acute myocardial infarction (AMI) is a substantial cause of morbidity and mortality in Canada. Evidence suggests that the incidence and mortality of AMI increase in the winter. Determining the strength and nature of seasonality patterns in relation to age and sex may be helpful in health care planning. OBJECTIVES: To examine the seasonal patterns of AMI hospital admissions by age and sex, to assess the strength of the seasonal patterns and to examine the overall trends in admissions. METHODS: A retrospective population-based study was conducted to assess temporal patterns in 14 years of hospital admissions for AMI (from April 1, 1988, to March 31, 2002) in Ontario. Seasonality was assessed using the autoregression coefficient (R2Autoreg), and Fisher's Kappa and Bartlett's Kolmogorov-Smirnov tests. RESULTS: There were 271,321 people in the cohort, of whom 63% (n = 171,546) were male and 37% (n = 99,775) were female. There was an increase in AMI admissions since 1988 that reached a plateau in 1992, which was attributable mostly to the increased rate in the oldest age groups (70 years and older), where admission rates more than doubled. An association between seasonality and AMI admissions was found in most age and sex groups, with men consistently exhibiting a stronger seasonality pattern. The greatest difference in the cohort, 2.5 per 100,000 per month (134 admissions), occurred between December and September (13.64 per 100,000 in September versus 16.14 per 100,000 in December). CONCLUSIONS: AMI admissions show seasonality patterns, which are more pronounced in men. Although statistically significant, the seasonal differences are small in terms of absolute numbers, and are likely irrelevant in health care planning.  相似文献   
992.
The original and early case reports of vasculitis provide a historical context and foundation for understanding current concepts of these diseases. These early case reports are valuable as reference points for the current efforts in diagnosing, treating, and classifying vasculitis. In addition, they emphasize the importance of careful clinical observation in these efforts and the essential nature of medical science. Polyarteritis nodosa was the first noninfectious vasculitis to be described and studied in detail. Research on this group of vasculitides has been the cornerstone for understanding the pathophysiology of other forms of idiopathic vasculitis. Historically, most forms of vasculitis described subsequently have been characterized and classified on the basis of features similar to or distinct from polyarteritis.  相似文献   
993.
994.
OBJECTIVE: To study lymphocyte markers in rheumatoid arthritis (RA)-associated interstitial pneumonitis (IP) compared with idiopathic IP. METHODS: Paraffin-embedded lung biopsy specimens from patients with RA (n = 15) and from those without RA (n = 16), all of whom had a diagnosis of either nonspecific IP or usual IP, were studied. Tissue sections from each patient were reviewed by a pathologist, who was blinded to the clinical data. Age and pulmonary function test results were similar in RA and non-RA patients. After high-temperature antigen unmasking, sections were incubated with mouse monoclonal antibodies directed against CD3, CD4, CD8, CD16, and CD20. All slides were coded, and digital images (100x magnification) of the entire tissue area were obtained. Staining was quantified using computer-assisted image analysis. RESULTS: Staining for CD4 was more prominent in patients with RA than in the non-RA comparison group (median 9.3 cells/mm(2), interquartile range [IQR] 5.5-27.3 versus 0.6 cells/mm(2), IQR 0.2-1.9; P = 0.002). CD4+ cell counts were increased in RA patients with nonspecific IP as well as in RA patients with usual IP, with no major difference between these groups. Results were similar for quantification of CD3 (P = 0.012). There was a less striking trend toward more CD8+ cells in RA patients (P = 0.27 versus those with non-RA lung disease). CONCLUSION: IP lesions in patients with RA are characterized by an increased number of CD4+ cells, as compared with that in patients with idiopathic IP. This finding suggests that CD4+ T cells are critical for the development of pulmonary manifestations in RA, and may have implications for the treatment of RA-associated lung disease.  相似文献   
995.

Purpose of Review

As the ongoing epidemic of adult and childhood obesity grows, it puts a greater burden on individuals and the healthcare system due to increased prevalence of obesity-associated diseases. An important area that has gained much attention recently is the sex and gender difference related to obesity and associated complications. Basic science and clinical studies have now improved our understanding of obesity and have discovered adipose tissue biology to be key in metabolism.

Recent Findings

There is evidence related to the sex dichotomy in obesity in a variety of areas including adipocyte function, sex hormone effects, genetics, and metabolic inflammation leading to critical differences in adipose tissue biology.

Summary

The sex and gender difference in adipose tissue is a factor that should be considered when studying an individuals’ risk for obesity and metabolic dysfunction. This understanding is important for strategizing treatment and prevention measures.
  相似文献   
996.
997.
998.
BACKGROUND/AIMS: To analyze the barriers to HCV treatment in HIV-HCV co-infected patients and their evolution between 2004 and 2006. METHODS: Three hundred and eighty HIV-HCV co-infected patients were prospectively included in surveys from November 22 to 29, 2004 (2004 survey), and 416 from April 3 to 10, 2006 (2006 survey). RESULTS: Patients in 2006 compared to those in 2004 had negative HCV RNA more often (24% vs. 12%). The rate of liver biopsy was similar (56% vs. 54%) while 24% had had a non-invasive liver damage assessment. The rate of previous treatment for HCV infection was higher (48% vs. 26%). The main reasons for HCV non-treatment have changed: HCV treatment deemed questionable (44% vs. 53%), lack of liver biopsy (18% vs. 33%), physicians' conviction of poor patient compliance (20% vs. 30%). In both surveys, HCV treated patients were more often of European origin, had better control of HIV infection, and had a liver damage assessment more often. CONCLUSIONS: The care of HIV-HCV co-infected patients has changed significantly in "real life". These results underline the importance of continuing efforts to educate physicians and patients in order to increase the access of co-infected patients to HCV treatment.  相似文献   
999.
This paper reports on the identification and full chemical characterization of isotonitazene (N,N‐diethyl‐2‐[5‐nitro‐2‐({4‐[(propan‐2‐yl)oxy]phenyl}methyl)‐1H‐benzimidazol‐1‐yl]ethan‐1‐amine), a potent NPS opioid and the first member of the benzimidazole class of compounds to be available on online markets. Interestingly, this compound was sold under the name etonitazene, a structural analog. Identification of isotonitazene was performed by gas chromatography mass spectrometry (GC–MS) and liquid chromatography time‐of‐flight mass spectrometry (LC‐QTOF‐MS), the latter identifying an exact‐mass m/z value of 411.2398. All chromatographic data indicated the presence of a single, highly pure compound. Confirmation of the specific benzimidazole regio‐isomer was performed using 1H and 13C NMR spectroscopy, after which the chemical characterization was finalized by recording Fourier‐transform (FT‐IR) spectra. A live cell‐based reporter assay to assess the in vitro biological activity at the μ‐opioid receptor (MOR) revealed that isotonitazene has a high potency (EC50 of 11.1 nM) and efficacy (Emax 180% of that of hydromorphone), thus confirming that this substance is a strong opioid. Isotonitazene has not been previously detected, either in powder form, or in biological fluids. The high potency and efficacy of isotonitazene, combined with the fact that this compound was being sold undiluted, represents an imminent danger to anyone aiming to use this powder.  相似文献   
1000.
SARS-CoV-2 (CoV2) antibody therapies, including COVID-19 convalescent plasma (CCP), monoclonal antibodies, and hyperimmune globulin, are among the leading treatments for individuals with early COVID-19 infection. The functionality of convalescent plasma varies greatly, but the association of antibody epitope specificities with plasma functionality remains uncharacterized. We assessed antibody functionality and reactivities to peptides across the CoV2 and the 4 endemic human coronavirus (HCoV) genomes in 126 CCP donations. We found strong correlation between plasma functionality and polyclonal antibody targeting of CoV2 spike protein peptides. Antibody reactivity to many HCoV spike peptides also displayed strong correlation with plasma functionality, including pan-coronavirus cross-reactive epitopes located in a conserved region of the fusion peptide. After accounting for antibody cross-reactivity, we identified an association between greater alphacoronavirus NL63 antibody responses and development of highly neutralizing antibodies against CoV2. We also found that plasma preferentially reactive to the CoV2 spike receptor binding domain (RBD), versus the betacoronavirus HKU1 RBD, had higher neutralizing titer. Finally, we developed a 2-peptide serosignature that identifies plasma donations with high anti-spike titer, but that suffer from low neutralizing activity. These results suggest that analysis of coronavirus antibody fine specificities may be useful for selecting desired therapeutics and understanding the complex immune responses elicited by CoV2 infection.  相似文献   
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