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111.
This study develops an explanatory framework for fear of neighborhood crime based on respondents' social context and local rates of assault injuries. Rates of assault injuries within zip codes are based on hospital discharge records. We find that only four variables have a significant unique contribution to fear of crime: respondent's sex, perceptions of neighborhood social capital, and the rates of struck by/against assault injuries for the 10–24 and 50+ age groups. We also find that the perception of neighborhood social capital moderates the impact of assault injury rates on fear of crime; those who perceive a high level of neighborhood social capital exhibit less sensitivity to assault injury rates. We include a map of assault injury rates and fear of crime by ZIP Code and describe the community context related to our results. © 2007 Wiley Periodicals, Inc. J Comm Psychol 35: 483–498, 2007.  相似文献   
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目的:探讨内皮细胞清除补体攻膜复合物(MAC)的途径及其清除动力学,方法:原代培养的人脐静脉内皮细胞以RH414荧光标记质膜双层,0℃组装亚溶剂量的MAC,37℃复苏后,LSCM实时监MAC沉积诱导的质膜囊泡化形成和胞吞,胞吐情况,流式细胞仪定量检测内皮细胞表面MAC抗原的清除情况,结果:MAC沉积后,内皮细胞有的质膜囊泡化形成,囊泡以胞吞和胞吐2种方式离开细胞,并以前者占优,37度条件下,内皮细胞清除表面MAC的半衰期约为5min。结论:内皮细胞可通过胞吞和胞吐2种机制清除细胞表面沉积的MAC,并以胞吞方式为主。  相似文献   
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We report a case of ruptured mycotic aneurysm involving innominate artery requiring an urgent surgical treatment. A 62-yr-old woman presented with fever and dyspnea. Previously, she was diagnosed with colon cancer and received right hemicolectomy and one cycle of adjuvant chemotherapy. On echocardiogram, pericardial effusion was noted and emergency pericardiocentesis was performed. CT scan revealed aortic aneurysm involving ascending aorta and innominate artery, and thrombi surrounding those structures. Patch repair of the defect in the ascending aorta and ringed Goretex graft to bypass the innominate and ascending aorta were performed. We believe that this is the first case of ruptured mycotic aneurysm involving innominate artery.  相似文献   
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Chickens have two major regions encoding major histocompatibility complex (MHC) class Iα genes and MHC class IIß genes, the serological and functional B‐system and the Rfp‐Y‐system. Recently, they have been shown to assort in a genetically independent way although still located on the same microchromosome. Moreover, the monomorphic MHC class IIα gene maps at a third locus located 5 c m from the nearest class IIß genes, located in the B‐system ( Kaufman et al., 1995 ). A pedigree family was studied in three generations in order to assign MHC class IIß restriction fragments observed in Southern blot analyses to either the B‐system, the Rfp‐Y‐system or the B‐Lα locus. In this study, we demonstrate by classical genetic testing of chickens within this fully pedigreed family the existence of an MHC class II‐like polymorphic restriction fragment that segregates independently of the B‐system, the Rfp‐Y‐system and of the B‐Lα locus.  相似文献   
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Summary: In the present contribution, the electrostatic spinning or electrospinning technique was used to produce ultra‐fine polyamide‐6 (PA‐6) fibers. The effects of solution conditions on the morphological appearance and the average diameter of as‐spun fibers were investigated by optical scanning (OS) and scanning electron microscopy (SEM) techniques. It was shown that the solution properties (i.e. viscosity, surface tension and conductivity) were important factors characterizing the morphology of the fibers obtained. Among these three properties, solution viscosity was found to have the greatest effect. Solutions with high enough viscosities (viz. solutions at high concentrations) were necessary to produce fibers without beads. At a given concentration, fibers obtained from PA‐6 of higher molecular weights appeared to be larger in diameter, but it was observed that the average diameters of the fibers from PA‐6 of different molecular weights had a common relationship with the solution viscosities which could be approximated by an exponential growth equation. Raising the temperature of the solution during spinning resulted in the reduction of the fiber diameters with higher deposition rate, while mixing m‐cresol with formic acid to serve as a mixed solvent for PA‐6 caused the solutions to have higher viscosities which resulted in larger fiber diameters. Lastly, the addition of some inorganic salts resulted in an increase in the solution conductivity, which caused the fiber diameters to increase due to the large increase in the mass flow.

Average diameter of as‐spun fibers plotted as a function of the viscosity of the solutions.  相似文献   

118.
Tumor growths, migraine headaches, and other health‐related complications reported in patients with neurofibromatosis type 1 (NF1) are often associated with pain. Thus, this study sought to describe and quantify the pain experience in children and young adults with NF1. Surveys were administered to 49 participants (28 children and 21 adults), ages 8 through 40 years. The survey included the Numeric Rating Scale 11 (NRS11) to assess pain intensity and the Patient Reported Outcomes Measurement Information System (PROMIS) to assess pain interference. A supplemental survey was created to measure pain frequency, chronicity, quality, and location. Results suggest pain is not only present in 55% of the cohort, but that it can begin at early ages. Pain was chronic in 35% of participants, with 41% reporting the use of medication to manage pain symptoms. Common sources of pain included migraine headaches and NF‐related tumors. Pain was described as having neuropathic features (i.e., burning, tingling, numbness, or itching), and was localized to the head, back, and extremities. Further, subsets of participants reported moderate‐to‐severe pain intensity, high frequency of pain, and interference of pain in daily activities. Continued investigation of the pain experience in a multisystem disorder, such as NF1, remains essential to providing guidance in the setting of complex pain management.  相似文献   
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