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排序方式: 共有4182条查询结果,搜索用时 15 毫秒
41.
Ari Whiteman Alice Wang Kelly McCain Betsy Gunnels Robin Toblin James Tseryuan Lee Carolyn Bridges Laura Reynolds Bhavini Patel Murthy Judy Qualters James A. Singleton Kimberley Fox Shannon Stokley LaTreace Harris Lynn Gibbs-Scharf Neetu Abad Kathryn A. Brookmeyer Susan Farrall Cassandra Pingali Anita Patel Ruth Link-Gelles Sharoda Dasgupta Radhika Gharpure Matthew D. Ritchey Kamil. E. Barbour 《MMWR. Morbidity and mortality weekly report》2021,70(19):725
42.
Mattila A Miettinen A Heinonen PK 《Infectious diseases in obstetrics and gynecology》1994,1(6):265-268
Objective: The aim of the study was to determine the currently most frequent microbial findings in Bartholin's duct abscess.Methods: Computerized records of microbial findings of 249 cases of Bartholin's duct abscess were retrospectively studied.Results: In 129 cases, only 1 microbe and, in 117 cases, >1 microbe were recovered. In 3 cases, the flora was recorded as normal for the lower genital tract. Of all bacteria isolated, 252 were aerobic or facultative and 108 were anaerobic or microaerophilic. Aerobic or facultative bacteria alone caused 142 (57%) of the 249 cases, Escherichia coli being the most frequent isolate in this group. Anaerobic or microaerophilic bacteria alone caused 33 cases (13%), Bacteroides species and Prevotella species being most frequently identified. Both aerobic or facultative and anaerobic or microaerophilic bacteria were isolated in 70 cases (28%). Candida albicans alone caused 1 case of Bartholin's duct abscess. The sexually transmitted pathogens Neisseria gonorrhoeae and Chlamydia trachomatis were both involved in only 2 cases.Conclusions: Bartholin's duct abscess was mainly caused by opportunistic bacteria, and sexually transmitted pathogens were only rarely involved in its pathogenesis. Since potentially pathogenic bacterial species were also frequently isolated, the use of antibiotics to complement the surgical treatment of Bartholin's duct abscess seems advisable, especially in patients with systemic symptoms. 相似文献
43.
Vitamin C and other compounds in vitamin C rich food in relation to risk of tuberculosis in male smokers. 总被引:1,自引:0,他引:1
H Hemil? J Kaprio P Pietinen D Albanes O P Heinonen 《American journal of epidemiology》1999,150(6):632-641
To examine whether vitamin C rich food consumption and related vitamin C intake are associated with the risk of tuberculosis, the authors analyzed 167 incident cases of tuberculosis during a median follow-up time of 6.7 years in a clinical trial cohort of 26,975 Finnish men for whom they had baseline dietary data. A highly statistically significant inverse association between calculated vitamin C intake and the incidence of tuberculosis was found, but adjustment for non-dietary factors weakened the association to nonsignificant. Furthermore, the risk of tuberculosis decreased with increasing intake of fruits, vegetables, and berries independent of vitamin C intake. Subjects who had dietary vitamin C intake >90 mg/day and who consumed more than the average amount of fruits, vegetables, and berries had a significantly lower risk of tuberculosis (adjusted relative risk = 0.40; 95% confidence interval 0.24, 0.69). Associations between dietary vitamin C intake and occurrence of various diseases without proper control of confounding have often been interpreted as causal. These findings show that such associations can be confounded even by some other dietary components. Lower tuberculosis incidence in subjects who consumed more fruits, vegetables, and berries poor in vitamin C suggests that other compounds in such a diet may reduce the risk of tuberculosis. 相似文献
44.
Context Many recent cross-sectional studies have suggested that lack of early exposure to communicable diseases, including measles, in affluent countries may have increased rates of atopic disease. Objective To study the association between natural measles infection and atopy. Design and Setting Cross-sectional nationwide study in Finland using data gathered between November 1, 1982, and June 30, 1986. Subjects A total of 547,910 individuals aged 14 months to 19 years who at the time of measles-mumps-rubella (MMR) vaccination had relevant information collected on the occurrence of measles and allergic rhinitis, eczema, and asthma. Main Outcome Measures Lifetime occurrence of atopic manifestations in subjects who had had measles compared with those who had not, expressed as age-specific and age-adjusted prevalence ratios. Results The age-adjusted prevalence ratio of atopic manifestations among those who had had measles (n = 20,690) compared with those who had not (n = 527,220) was 1.32 (95% confidence interval [CI], 1.27-1.36) for eczema, 1.41 (95% CI, 1.33-1.49) for rhinitis, and 1.67 (95% CI, 1.54-1.79) for asthma. The positive association between measles and atopy was evident at all ages, in both urban and rural dwellers, and among subjects with many or few contacts at home or in day care. Conclusions Based on our data, measles and atopy occur more frequently together than expected, which does not support the hypothesis that experiencing natural measles infection offers protection against atopic disease. 相似文献
45.
Smoking, alcohol use, and physical activity: a 13-year longitudinal study ranging from adolescence into adulthood. 总被引:3,自引:0,他引:3
PURPOSE: To assess the associations among smoking, alcohol use, and physical activity, and to assess how the health behaviors predict changes in other health behaviors from adolescence to adulthood. METHODS: Subjects were the participants of the North Karelia Youth Project study from six schools in Eastern Finland. At the baseline in 1978 they were 13-year-olds (n = 903) and in the last of the six surveys in 1993 they were 28-year-olds. This study uses the data from three surveys in which the participants were 15-, 21-, and 28-year olds. The response rate was 71% in the last survey. Data were analysed by SPSS software. RESULTS: Smoking prevalence was highest at the age of 21 years and alcohol use at the age of 28 years. The prevalence of leisure-time physical activity did not change much over time. Smoking and alcohol use correlated positively for each survey. Smoking correlated negatively with leisure-time physical activity. The best predictors for each health behavior were the same behaviors measured before, but smoking had the strongest level of continuity. In addition, alcohol use at the age of 15 years predicted smoking at the ages of 21 years and 28 years, but smoking in adolescence did not predict alcohol use in adulthood. CONCLUSIONS: Smoking was associated with both alcohol use and physical activity and therefore has a central role among health behaviors. Smoking and alcohol use were particularly clearly related from adolescence to adulthood. Smoking behavior was the most constant behavior. 相似文献
46.
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48.
Genomic profile of pseudomyxoma peritonei analyzed using next‐generation sequencing and immunohistochemistry
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Pirjo Nummela Lilli Saarinen Alexandra Thiel Petrus Järvinen Rainer Lehtonen Anna Lepistö Heikki Järvinen Lauri A Aaltonen Sampsa Hautaniemi Ari Ristimäki 《International journal of cancer. Journal international du cancer》2015,136(5):E282-E289
Pseudomyxoma peritonei (PMP) is a relatively rare clinical syndrome characterized by neoplastic epithelial cells growing in the peritoneal cavity and secreting mucinous ascites. Our aim was to explore the molecular events behind this fatal but under‐investigated disease. We extracted DNA from 19 appendix‐derived PMP tumors and nine corresponding normal tissues, and analyzed the mutational hotspot areas of 48 cancer‐related genes by amplicon‐based next‐generation sequencing (NGS). Further, we analyzed the protein expression of V600E mutated BRAF, MLH1, MSH2, MSH6 and p53 from a larger set of PMP tumors (n = 74) using immunohistochemistry. With NGS, we detected activating somatic KRAS mutations in all of the tumors studied. GNAS was mutated in 63% of the tumors with no marked difference between low‐grade and high‐grade tumors. Only one (5.3%) tumor showed oncogenic PIK3CA mutation, one showed oncogenic AKT1 mutation, three (15.8%) showed SMAD4 mutations and none showed an APC mutation. P53 protein was aberrantly expressed in higher proportion of high‐grade tumors as compared with low‐grade ones (31.3 vs. 7.1%, respectively; p = 0.012) and aberrant expression was an independent factor for reduced overall survival (p = 0.002). BRAF V600E mutation was only found in one (1.4%) high‐grade tumor by immunohistochemistry (n = 74). All the studied tumors expressed mismatch repair proteins MLH1, MSH2 and MSH6. Our results indicate that KRAS mutations are evident in all and GNAS mutations in most of the PMPs, but BRAF V600E, PIK3CA and APC mutations are rare. Aberrantly expressed p53 is associated with high‐grade histology and reduced survival. 相似文献
49.
Home‐Based Exercise Training Improves Left Ventricle Diastolic Function in Survivors of Childhood ALL: A Tissue Doppler and Velocity Vector Imaging Study
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50.
Ru-Jin Huang Thorsten Hoffmann Jurgita Ovadnevaite Ari Laaksonen Harri Kokkola Wen Xu Wei Xu Darius Ceburnis Renyi Zhang John H. Seinfeld Colin ODowd 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(32)
The gas-phase formation of new particles less than 1 nm in size and their subsequent growth significantly alters the availability of cloud condensation nuclei (CCN, >30–50 nm), leading to impacts on cloud reflectance and the global radiative budget. However, this growth cannot be accounted for by condensation of typical species driving the initial nucleation. Here, we present evidence that nucleated iodine oxide clusters provide unique sites for the accelerated growth of organic vapors to overcome the coagulation sink. Heterogeneous reactions form low-volatility organic acids and alkylaminium salts in the particle phase, while further oligomerization of small α-dicarbonyls (e.g., glyoxal) drives the particle growth. This identified heterogeneous mechanism explains the occurrence of particle production events at organic vapor concentrations almost an order of magnitude lower than those required for growth via condensation alone. A notable fraction of iodine associated with these growing particles is recycled back into the gas phase, suggesting an effective transport mechanism for iodine to remote regions, acting as a “catalyst” for nucleation and subsequent new particle production in marine air.Marine aerosol formation contributes significantly to the global radiative budget given the high susceptibility of marine stratiform cloud radiative properties to changes in cloud condensation nuclei (CCN) availability. Atmospheric new-particle-formation is thought to involve nucleation of sulfuric acid with water, ammonia, or amines followed by condensation/growth in the presence of organic vapors (1, 2). Unique in the marine boundary layer (MBL), new particle formation involves sequential addition of HIO3 or clustering of iodine oxides (IxOy) (3, 4). In specific source regions such as coastal zones, seaweed beds, or snowpack/pack-ice, iodine oxide nucleation can be a driving force for nucleation (5–7). Over Arctic waters, nonetheless, one study finds insufficient iodic acid vapors to grow nucleated particles to CCN sizes (8), whereas another study finds that both nucleation and growth are almost exclusively driven by iodic acid (9). Over the open ocean, the supply of iodine oxides has been thought to be limited; however, recent measurements suggest that significant reactive iodine chemistry can occur in these regions (10). Moreover, observational evidence exists for open ocean particle formation and growth, especially when oceanic productivity is high (11, 12). An increase in atmospheric iodine levels in the North Atlantic since the mid-20th century has been shown to be driven by growth of anthropogenic ozone and enhanced subice phytoplankton production (13). While the reported IO concentration (0.4–3.1 ppt) in the remote MBL (10, 14, 15) is likely sufficient for formation of prenucleation clusters (∼1 nm), growth of these initial clusters requires the presence of other condensable vapors (16). Since preexisting aerosol particles act as a strong sink for the nucleated clusters, thus inhibiting atmospheric aerosol and CCN formation (17, 18), this early growth phase is essential for their survival. Whereas sulfuric acid vapor is also involved in nucleation, its level in remote open ocean is generally too low (105 molecules cm−3) to support subsequent particle growth, leaving organic vapors as the most plausible alternative for particle growth.In the marine atmosphere, condensing organics must originate from the oxidation of marine volatile organic compounds (VOCs), which predominantly comprise C1–C5 VOCs (e.g., isoprene) released from phytoplankton. Principal high volatility oxidation products consist of intermediate oxidized organics (IOOs), such as polyhydric alcohols (e.g., tetrols) or polyfunctional carbonyls (e.g., glyoxal) (19–22). Nonetheless, growth of available prenucleation clusters/nanometer particles requires condensing organic molecules of low effective volatilities (i.e., saturation mass concentration, C* < ∼10−3 μg m−3); otherwise, preferential condensation of the organic mass to larger-diameter particles would occur (23, 24). Formation of such extremely low-volatility organic compounds (ELVOCs) from gas-phase reaction is well established for monoterpene oxidation products (25, 26).A potential pathway for formation of low-volatility organics could also result from particle-phase chemical reactions induced by iodine oxides in the early stages of marine particle formation. When the underlying chemistry is sufficiently fast, kinetic condensation occurs, resulting in particles with diameters smaller than about 50 nm growing at the same rate (e.g., nm h−1) (24). If, however, particle-phase chemistry is preferentially favored in the smallest particles (i.e., stemming from the higher relative concentration of iodine oxides in freshly formed marine particles), growth of the nucleated particles could proceed more rapidly, as compared to that in which gas-phase chemistry is the source of the low-volatility compounds (23).In this paper, we present experimental results from field measurements as well as laboratory studies of nanometer particle growth and derive a plausible chemical mechanism from the results that can explain the observations of ultrafine particle growth in the marine atmosphere. The results suggest that both iodine and condensed organics contribute to particle growth from a nascent nucleation mode into an ultrafine particle mode. Moreover, laboratory studies of the growth of seed iodine oxide particles (IOP) via heterogeneous reactions with organic vapors suggest a hitherto unrecognized mechanism that fast-tracks the growth of nucleation mode clusters into survivable aerosol particles. In this process, a notable fraction of the iodine associated with these growing particles is recycled back to the gas phase, suggesting a transport mechanism for iodine to remote regions. 相似文献