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Ohne ZusammenfassungVortrag in der XXVI. Wanderversammlung der ung. Aerzte u. Naturforscher in Kronstadt.  相似文献   
73.
Illitic clays are the commonly used material in building ceramics. Zeolites are microporous, hydrated crystalline aluminosilicates, they are widely used due to their structure and absorption properties. In this study, illitic clay (Füzérradvány, Hungary) was mixed with natural zeolite (Nižný Hrabovec, Slovakia) with up to 50 wt.% of zeolite content. The samples were submitted to thermal analyses, such as differential thermal analysis, differential scanning calorimetry, thermogravimetry, and dilatometry. In addition, the evolution of thermal diffusivity, thermal conductivity, and specific heat capacity in the heating stage of firing were measured and discussed. The amount of the physically bound water in the samples increased along with the amount of zeolite. The temperature of the illite dehydroxylation (peak temperature) was slightly shifted to lower temperatures, from 609 °C to 575 °C (for sample IZ50). On the other hand, the mass loss and the shrinkage of the samples significantly increased with the zeolite content in the samples. Sample IZ50 reached 10.8% shrinkage, while the sample prepared only from the illitic clay contracted by 5.8%. Nevertheless, the temperature of the beginning of the sintering (taken from the dilatometric curves) decreased from 1021 °C (for illitic clay) to 1005 °C (for IZ50). The thermal diffusivity and thermal conductivity values decreased as the amount of zeolite increased in the samples, thus showing promising thermal insulating properties.  相似文献   
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Background: Synchronization between 0.1‐Hz rhythms in cardiovascular system is deteriorated at acute myocardial infarction (AMI) leading to a disruption of natural functional couplings within the system of autonomic regulation. Objective: This study evaluates the prognostic value of autonomic regulation indices for the 5‐year risk of fatal and nonfatal cardiovascular events in patients after AMI. Methods and Results: We studied 125 patients (53 [42%] female) after AMI aged between 30 and 83 years. The period of observation was 5 years with checkpoints at the first week after AMI and after each year after AMI. We compared the prognostic value of established clinical characteristics and degree S of synchronization between 0.1‐Hz rhythms in heart rate and microcirculation for evaluation of the 5‐year risk of mortality and recurrent myocardial infarction (MI) in patients after AMI. Acute heart failure Killip 2–4 at AMI and S < 20% at the first week after AMI were identified as the most important factors for evaluation of the risk of 5‐year mortality in patients after AMI (χ2= 14.2, P = 0.003). Sensitivity and specificity of low S (<20%) at the first week after AMI were 76% and 43%, respectively. For evaluation of the 5‐year risk of recurrent MI index S had no advantage over established clinical characteristics. Conclusion: The value of S below 20% in patients with AMI is a sensitive marker of high risk of mortality during the subsequent five years. It is characterized by better prognostic value than most of established clinical characteristics.  相似文献   
76.
Mobile phone social networking applications such as GRINDR are potential tools for recruitment of men who have sex with men (MSM) for HIV prevention research. Demographics and sexual risk behaviors of men recruited through GRINDR and through traditional media were compared. GRINDR participants were younger (mean age 31 vs. 42, p?<?0.0001), more White identified (44 vs. 30?%, p?<?0.01), and had more sex partners in the previous 14 days (1.88 vs. 1.10, p?<?0.05) than other recruits. Email responses were less successful for enrollment than phone calls (5 vs. 50?%). This approach resulted in successful recruitment of younger and more educated, White identified MSM.  相似文献   
77.
ABSTRACT: BACKGROUND: Heart failure is likely to be particularly prevalent in the nursing home population, but reliable data about the prevalence of heart failure in nursing homes are lacking. Therefore the aims of this study are to investigate (a) the prevalence and management of heart failure in nursing home residents and (b) the relation between heart failure and care dependency as well as heart failure and quality of life in nursing home residents METHODS: Nursing home residents in the southern part of the Netherlands, aged over 65 years and receiving long-term somatic or psychogeriatric care will be included in the study. A panel of two cardiologists and a geriatrician will diagnose heart failure based on data collected from actual clinical examinations (including history, physical examination, ECG, cardiac markers and echocardiography), patient records and questionnaires. Care dependency will be measured using the Care Dependency Scale. To measure the quality of life of the participating residents, the Qualidem will be used for psychogeriatric residents and the SF-12 and VAS for somatic residents. CONCLUSION: The study will provide an insight into the actual prevalence and management of heart failure in nursing home residents as well as their quality of life and care dependency. Trial registration: Dutch trial register NTR2663.  相似文献   
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We assessed the acceptability of three of over-the-counter products representative of potential rectal microbicide (RM) delivery systems. From 2009 to 2010, 117 HIV-uninfected males (79 %) and females (21 %) who engage in receptive anal intercourse participated in a 6-week randomized crossover acceptability trial. Participants received each of three products (enema, lubricant-filled applicator, suppository) every 2 weeks in a randomized sequence. CASI and T-ACASI scales assessed product acceptability via Likert responses. Factor analysis was used to identify underlying factors measured by each scale. Random effects models were fit to examine age and gender effects on product acceptability. Three underlying factors were identified: Satisfaction with Product Use, Sexual Pleasure, and Ease of Product Use. For acceptability, the applicator ranked highest; however, differences between product acceptability scores were greatest among females and younger participants. These findings indicate that RM delivery systems impact their acceptability and should be considered early in RM development to enhance potential use.  相似文献   
80.
Encouraging results from our previous studies of sentinel lymph node (SLN) mapping in colorectal cancer (CRC) prompted investigation of its feasibility and accuracy during laparoscopic colectomy for early CRC. Between 1996 and 2000, 14 patients with clinically localized colorectal neoplasms underwent colonoscopic tattooing of the primary site and SLN mapping. In each case 0.5 to 1 cm3 of isosulfan blue dye was injected submucosally via the colonoscope. The blue-stained lymphatics were visualized through the laparoscope and followed to the SLN, which was marked with a clip, and laparoscopic colectomy was completed in the routine fashion. All lymph nodes were examined by hematoxylin and eosin (H&E) staining; in addition each SLN was subjected to focused examination by multisectioning and immunohistochemical staining using cytokeratin antibody. In all 14 patients the primary neoplasm and an SLN were identified laparoscopically. An average of 13.5 total lymph nodes and 1.7 SLNs per patient were identified. The SLN correctly reflected the tumor status of the nodal basin in 93 per cent of the cases. In four cases with unexpected lymphatic drainage, the extent of mesenteric resection was altered. In two cases (14%), nodal involvement was micrometastatic, confined to an SLN, and identified only by immunohistochemical staining. Lymphatic mapping caused no complications and added only 10 to 15 minutes to the overall operative time. Comparison of results in this group with results for a matched group of 14 patients undergoing SLN mapping during open colon resection showed that the laparoscopic technique had similar rates of accuracy and success. These preliminary findings indicate that colonoscopic/laparoscopic SLN mapping during laparoscopic colon resection is a feasible and technically simple means of identifying the primary colorectal neoplasm and its SLN. Focused pathologic examination of this node can upstage CRC and thereby may improve selection of patients for adjuvant chemotherapy.  相似文献   
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