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131.
摘要 目的:观察重症急性胰腺炎(SAP)合并腹腔感染(IAI)患者病原菌分布,分析药物敏感性,同时探讨其院内死亡的危险因素。方法:本研究纳入2017年1月~2022年1月期间来解放军联勤保障部队第九二二医院接受治疗并确诊的SAP合并IAI患者100例,采集患者腹水标本,观察其病原菌分布,分析药物敏感性。入院后收集患者人口学特征、实验室检查等资料,探讨患者院内死亡的危险因素。结果:100例SAP合并IAI患者腹水标本中,分离出186株病原菌,其中革兰阴性菌有108株,占比58.06%。革兰阳性菌51株,占比27.42%。真菌27株,占比14.52%。鲍曼不动杆菌对不同抗菌药物的敏感性均较低,大肠埃希菌对厄他培南、亚胺培南、哌拉西林/他唑巴坦、庆大霉素、美罗培南的敏感性较高,肺炎克雷伯菌对亚胺培南、美罗培南的敏感性较高,葡萄球菌属对替加环素、万古霉素、利奈唑胺的敏感性较高,屎肠球菌对替加环素、利奈唑胺的敏感性较高,粪肠球菌对氨苄西林、万古霉素、环丙沙星、替加环素的敏感性较高。单因素分析显示,SAP合并IAI患者院内死亡与器官障碍数目、膀胱压、入院时急性生理学与慢性健康状况评分(APACHE II)评分、白细胞计数(WBC)、血钙、红细胞压积(HCT)、总胆固醇(TC)、甘油三醋(TG)、降钙素原(PCT)、C反应蛋白(CRP)、动脉二氧化碳分压(PaCO2)、动脉氧分压(PaO2)有关(P<0.05)。多因素Logistic回归分析结果显示:器官障碍数目偏多、血钙偏低、CRP偏高、APACHE II评分偏高、膀胱压偏高、PaO2偏低、WBC偏高是导致SAP合并IAI患者院内死亡的危险因素(P<0.05)。结论:SAP合并IAI患者病原菌分布以革兰阴性菌为主,主要的革兰阴性菌、革兰阳性菌耐药率高。此外,器官障碍数目偏多、血钙偏低、CRP偏高、APACHE II评分偏高、膀胱压偏高、PaO2偏低、WBC偏高是影响SAP合并IAI患者院内死亡的危险因素。 相似文献
132.
摘要 目的:探讨高危结直肠腺瘤的影响因素,构建风险预测模型并验证。方法:回顾性分析2021年1月至2021年12月期间在江苏大学附属人民医院进行诊疗的1408例结直肠腺瘤患者的资料,根据病理特征分为高危结直肠腺瘤组(759例)和非高危结直肠腺瘤组(649例)。采用Logistic回归分析筛选高危结直肠腺瘤的独立危险因素并建立风险预测模型,并验证预测模型的应用效能。结果:Logistic回归分析结果显示,病灶部位为直肠、高血压、高脂血症、年龄≥53岁、吸烟是高危结直肠腺瘤的独立危险因素(P<0.05)。基于以上因素建立预测高危结直肠腺瘤风险的列线图模型,经Hosmer-Lemeshow检验和受试者工作特征曲线(ROC)分析显示,该风险预测模型具有较好的拟合度和预测效能,可以用于高危腺瘤的风险预测。结论:病灶部位为直肠、高血压、高脂血症、年龄≥53岁、吸烟是高危结直肠腺瘤的独立危险因素,临床医生可尽早对高危患者进行预防性干预以减缓高危腺瘤的发生。 相似文献
133.
Substance use disorders (SUDs) are highly prevalent and exact a large toll on individuals’ health, well-being, and social functioning. Long-lasting changes in brain networks involved in reward, executive function, stress reactivity, mood, and self-awareness underlie the intense drive to consume substances and the inability to control this urge in a person who suffers from addiction (moderate or severe SUD). Biological (including genetics and developmental life stages) and social (including adverse childhood experiences) determinants of health are recognized factors that contribute to vulnerability for or resilience against developing a SUD. Consequently, prevention strategies that target social risk factors can improve outcomes and, when deployed in childhood and adolescence, can decrease the risk for these disorders. SUDs are treatable, and evidence of clinically significant benefit exists for medications (in opioid, nicotine and alcohol use disorders), behavioral therapies (in all SUDs), and neuromodulation (in nicotine use disorder). Treatment of SUDs should be considered within the context of a Chronic Care Model, with the intensity of intervention adjusted to the severity of the disorder and with the concomitant treatment of comorbid psychiatric and physical conditions. Involvement of health care providers in detection and management of SUDs, including referral of severe cases to specialized care, offers sustainable models of care that can be further expanded with the use of telehealth. Despite advances in our understanding and management of SUDs, individuals with these conditions continue to be stigmatized and, in some countries, incarcerated, highlighting the need to dismantle policies that perpetuate their criminalization and instead develop policies to ensure support and access to prevention and treatment. 相似文献
134.
Nitrous oxide emissions from silage maize fields under different mineral nitrogen fertilizer and slurry applications 总被引:6,自引:1,他引:6
J.W. van Groenigen G.J. Kasper G.L. Velthof A. van den Pol-van Dasselaar P.J. Kuikman 《Plant and Soil》2004,263(1):101-111
Intensive dairy farming systems are a large source of emission of the greenhouse gas nitrous oxide (N2O), because of high nitrogen (N) application rates to grasslands and silage maize fields. The objective of this study was to compare measured N2O emissions from two different soils to default N2O emission factors, and to look at alternative emission factors based on (i) the N uptake in the crop and (ii) the N surplus of the system, i.e., N applied minus N uptake by the crop. Twelve N fertilization regimes were implemented on a sandy soil (typic endoaquoll) and a clay soil (typic endoaquept) in the Netherlands, and N2O emissions were measured throughout the growing season. Highest cumulative fluxes of 1.92 and 6.81 kg N2O-N ha–1 for the sandy soil and clay soil were measured at the highest slurry application rate of 250 kg N ha–1. Background emissions from unfertilized soils were 0.14 and 1.52 kg N2O-N ha–1 for the sandy soil and the clay soil, respectively. Emission factors for the sandy soil averaged 0.08, 0.51 and 0.26% of the N applied via fertilizer, slurry, and combinations of both. For the clay soil, these numbers were 1.18, 1.21 and 1.69%, respectively. Surplus N was linearly related to N2O emission for both the sandy soil (R2=0.60) and the clay soil (R2=0.40), indicating a possible alternative emission factor. We concluded that, in our study, N2O emission was not linearly related to N application rates, and varied with type and application rate of fertilizer. Finally, the relatively high emission from the clay soil indicates that background emissions might have to be taken into account in N2O budgets. 相似文献
135.
The relationship between birth weight and relative subcutaneous fat distribution at school age was considered in 131 boys and 106 girls 7 to 12 years of age. Relative fat distribution at school age was estimated with the ratio of the subscapular to triceps skinfolds (S/T) for the total sample, and with the ratio of the sum of two trunk (subscapular, midaxillary) to the sum of two extremity (triceps, medial calf) skinfolds (T/E) for subsamples of 102 boys and 63 girls. There were no sex differences in the S/T ratio (mm/mm), boys 0.62 ± 0.15, girls 0.63 ± 0.18; T/E ratio (mm/mm), boys 0.58 ± 0.13, girls 0.59 ± 0.16; and BMI (kg/m2), boys 17.1 ± 2.4, girls 16.9 ± 2.2. Second order partial correlations, controlling for age and the BMI or age and sum of skinfolds, between birth weight and the skinfold ratios are, respectively, ?0.22 and ?0.20 (p<0.01) for S/T and ?0.29 and ?032 (p<0.01) for T/E in girls, and ?0.18 and ?0.17 (p<0.05) for S/T and ?0.06 and ?0.6 for T/E in boys. Though low, the correlations suggest that as birth weight decreases proportionally more subcutaneous fat is accumulated on the trunk than on the extremities, more so in females than in males. Results of stepwise multiple regression analyses indicate that birth weight accounts for from 2% to 8% of the variance in relative subcutaneous fat distribution at school age. 相似文献
136.
Joseph E. Donnelly Dennis J. Jacobsen Janet E. Whatley James O. Hill Larry L. Swift Alan Cherrington Brent Polk Zung V. Tran George Reed 《Obesity (Silver Spring, Md.)》1996,4(3):229-243
Obesity and low levels of physical and metabolic fitness are risk factors for cardiovascular disease and diabetes. The purpose of this investigation was to attenuate obesity and improve physical and metabolic fitness in elementary school children. Schools have the opportunity, mechanisms, and personnel in place to deliver nutrition education, fitness activities, and a school food service that is nutritious and healthy. Cohorts from grades 3 to 5 in two school districts in rural Nebraska (Intervention/Control) participated in a 2-year study of physical activity and modified school lunch program. Data collection for aerobic capacity, body composition, blood chemistry, nutrition knowledge, energy intake, and physical activity was at the beginning and end of each year. Int received enhanced physical activity, grade specific nutrition education, and a lower fat and sodium school lunch program. Con continued with a regular school lunch and team sports activity program. At year 2, Int lunches had significantly less energy (9%), fat (25%), sodium (21%), and more fiber (17%). However, measures of 24-hour energy intake for Int and Con showed significant differences for sodium only. Physical activity in the classroom was 6% greater for Int compared to Con (p < 0.05) but physical activity outside of school was ?16 % less for Int compared to Con (p < 0.05). Body weight and body fat were not different between schools for normal weight or obese children. No differences were found for cholesterol, insulin, and glucose; however, HDL cholesterol was significantly greater and cholesterol/HDL was significantly less for Int compared to Con (p < 0.05). It appears that compensation in both energy intake and physical activity outside of school may be responsible for the lack of differences between Int and Con. 相似文献
137.
Fine root productivity was estimated in a lowland tropical rain forest at Los Tuxtlas (SE Mexico) and examined in relation to climatic factors. Two root diameter classes were defined (class I,<1 mm; class II, 1–3 mm). Total root productivity was estimated to 1.95 t ha–1 year–1, a value which is lower than those reported from other rain forest sites. Significant differences in root dry weight were found among months and between diameter classes throughout the year. Class I monthly means formed two groups: one corresponding to the months of highest precipitation, and the other to the relatively dry season. Class II monthly means also formed two groups, although these were unrelated to the regional precipitation pattern. A multiplicative regression model of productivity on precipitation was significant for both root classes when rainfall data of the previous month were used, while a linear regression model was significant only for class I roots when temperature data of two months before were used; these results suggest a delay in the effect of climatic conditions on root productivity. While the seasonal pattern of root productivity is clearly related to the annual rainfall distribution, the low total annual productivity may be related to the very high soil fertility at Los Tuxtlas. 相似文献
138.
139.
Koichi Matsuzaki Mikio Kan Wallace L. McKeehan 《In vitro cellular & developmental biology. Animal》1996,32(6):345-360
Summary Two transmembrane serine-threonine kinases (type I and II receptors), a membrane-anchored proteoglycan (type III), and a homodimeric
ligand participate in the transforming growth factor beta type on (TGFβ1) signal transduction complex. The expression of recombinant
receptors in insect cells co-infected with up to three recombinant baculoviruses was employed to study interactions among
the ectodomains of the three types of receptors and the TGFβ1 ligand in absence of uncontrollable extrinsic factors in mammalian
cells. Multi-subunit complexes were assembled in intact cells and purified on glutathione-conjugated beads for analysis by
tagging one of the subunits with glutathione S-transferase (GST). Intrinsic ligand-independent interactions were observed
among receptor subunits as follows: type III–III type I–I, type III-I, and type II-I. The homeotypic complex of type II–II
receptors and the heterotypic type III-II interaction was ligand dependent. The type I, but not the type III, subunit displaced
about 50% of the type II component in either ligand-dependent homomeric type II-type II complexes or heteromeric type III-type
II complexes to form type II-I or type III-II-I oligomers, respectively. The type II subunit displaced type I subunits in
oligomers of the type I subunit. Specificity of type I receptors may result from differential affinity for the type II receptor
rather than specificity for ligand. A monomeric subunit of the TGFβ1 ligand bound concurrently to type III and type II or
type III and type I receptors, but failed to concurrently bind to the type II and type I subunits. The binding of TGFβ1 to
the type I kinase subunit appears to require an intact disulfide-linked ligand dimer in the absence of a type III subunit.
The combined results suggest a pentameric TGFβ signal transduction complex in which one unit each of the type III, type II,
and type I components is assembled around the two subunits of the dimeric TGFβ1 ligand. An immobilized GST-tagged subunit
of the receptor complex was utilized to assemble multi-subunit complexesin vitro and to study the phosphorylation events among subunits in the absence of extrinsic cell-derived kinases. The results revealed
that (a) a low level of ligand-independent autophosphorylation occurs in the type I kinase; (b) a high level of autophosphorylation
occurs in the type II kinase; (c) both the type III and type I subunits aretrans-phosphorylated by the type II subunit; and (d) the presence of both type I and II kinases complexed with the type III subunit
and dimeric TGFβ1 ligand in a pentameric complex causes maximum phosphorylation of all three receptor subunits. 相似文献
140.
James B. Hoying Carl A. Boswell Stuart K. Williams 《In vitro cellular & developmental biology. Animal》1996,32(7):409-419
Summary During angiogenesis, the microvasculature displays both vessel remodeling and expansion under the control of both cellular
and extracellular influences. We have evaluated the role of angiogenic and angiostatic molecules on angiogenesis in anin vitro model that more appropriately duplicates the cellular and extracellular components of this process. Freshly isolated microvessel
fragments from rat adipose tissue (RFMF) were cultured within three-dimensional collagen I gels. These fragments were characterized
at the time of isolation and were composed of vessel segments observed in the microvasculature of fatin situ (i.e., arterioles, venules, and capillaries). Fragments also exhibited characteristic ablumenally associated cells including
smooth muscle cells and pericytes. Finally, fragments were encased in an extracellular matrix composed of collagen type IV
and collagen type I/III. The elongation of microvascular elements was subsequently evaluated using morphologic and immunocytochemical
techniques. The proliferation, migration, and elongation of cellular elements in microvessel fragments from rat adipose tissue
was dependent on initial fragment density, matrix density, and required serum. Inclusion of endothelial cell growth factors
to microvessel fragments from rat adipose tissue 3-D cultures resulted in the accelerated elongation of tube structures and
the expression of von Willebrand factor in cells constituting these tubes. Molecules with reported angiostatic capacity (e.g.,
transforming growth factor and hydrocortisone) inhibited vessel tube elongation.
In vitro methods have been developed to evaluate numerous mechanisms associated with angiogenesis, including endothelial cell proliferation,
migration, and phenotypic modulation. Microvascular endothelial cell fragments described in this study represent anin vitro population of cells that accurately duplicate thein vivo microcirculatory elements of fat. The proliferation of cells and elongation of microvascular elements subsequently observed
in three-dimensional cultures provides anin vitro model of angiogenesis. Microvascular formation in this system results from pre-existing microvessel fragments unlike tube
formation observed when cultured endothelial cells are placed in three-dimensional gels. This form of tube formation from
cultured endothelium is more characteristic of vasculogenesis. Thus, the formation of microvascular elements from microvessel
fragments provides the opportunity to examine the mechanisms regulating angiogenesis in anin vitro system amenable to precise experimental manipulation. 相似文献