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21.
We evaluated serum and urinary markers of bone turnover in 14 children with asthma during inhaled budesonide and nedocromil treatments. Both the markers of formation (serum carboxy- and amino-terminal propeptides of type I procollagen and serum osteocalcin) and the markers of degradation (serum carboxy-terminal telopeptide of type I collagen and urinary pyridinium cross-links) decreased (p < 0.05) during budesonide treatment for 6 months. During inhaled nedocromil treatment (for the following 6 months), the markers returned to the normal levels. These transient decreases in the markers of both formation and degradation of bone suggest that inhaled budesonide may slightly decrease the bone turnover rate. However, normal "coupling" between formation and degradation seemed to operate, e.g. a change in one resulted in a corresponding change in the other, so that net bone loss did not necessarily occur.  相似文献   
22.
Sense of virtual community (SOVC) reflects the feeling that individual members have of belonging to an online social group. Yet there is a lack of investigation focusing on its individual-level antecedents. We argue that in order to enhance understanding of how SOVC develops we first need to distinguish between the individual expectations, actions, and the resulting community-related feelings. Drawing upon the uses and gratifications approach, we explore the community members’ expected benefits, their linkages with different types of community participation and consequently with the experienced SOVC. We tested the hypotheses on a sample of 395 members of a virtual community hosted by a Finnish business newspaper. The findings suggest that both forms of participation – reading and posting messages – have a positive impact on SOVC, but the expected benefits differ. Participation by reading messages is mainly driven by the expectation of cognitive benefits, while posting messages seems to be largely driven by the anticipation of both social and personal integrative benefits. Our study contributes by providing a refined SOVC conceptualization and operationalization for virtual-community research, and by opening up the individual-level actions that build up a sense of virtual community.  相似文献   
23.
The dinuclear compound, 1, with the molecular formula of [Cu2(H3L)2(ClO4)2][Cu2(H3L)2(MeCN)2](ClO4)6 was prepared by the reaction of [bis-(1H-imidazol-2-yl)-methyl]-pyridin-2-yl-methylamine (H3L) with copper(II) perchlorate. The asymmetric unit of the crystal structure of 1 contains two dinuclear units, [Cu2(H3L)2(ClO4)2]2+ and [Cu2(H3L)2(MeCN)2]4+ (abbreviated as 1ClO4 and 1MeCN), respectively, and they are linked through hydrogen bonding between the oxygen atom from the axial coordinated perchlorate anions and one of the neighboring imidazole rings from 1MeCN. EPR spectroscopic studies of 1 in MeOH by addition of bridging ligands including NaN3 and NaOH were carried out and the reaction process was discussed.  相似文献   
24.
Are programs just scale-ups of projects, or do they represent something unique? Recent articles stress the difference of project and program management, but do neither show consensus nor precise definitions of program management. Our comparative bibliometric study of 517 program articles and 1164 project articles published in the last 21 years in leading scientific business journals identifies similarities and differences in theoretical foundations, indicated by the sources cited, and themes, indicated by the keywords. We show that programs have several theoretical bases, such as organizational theories, strategy, product development, manufacturing and change. Programs take an open system view and seek change in permanent organizations. Projects, in turn, have product development as the dominant theory basis. We elaborate eleven distinctive characteristics of program and project management research. Our study proposes themes upon which future theories and empirical studies of programs can be established.  相似文献   
25.
介绍了一种全新的、已获专利保护的、用单台混合成形单元生产容器用轻量双层箱纸板的成本效益型的概念。新概念将三个独特的部件和技术结合为一体:新型ValFloPro双层流浆箱、VacuBalence真空辅助成形板和ValFormer靴刮刀混合成形器技术。这个具备分层技术的混合成形新概念将纸机运行速度提高到1400m/min,是生产一流质量轻量箱纸板的一种切实可行的替代方案。  相似文献   
26.
The prevalence of Clostridium botulinum types A, B, E and F in river lampreys caught in Finnish rivers was determined for the first time using a quantitative PCR-MPN (most probable number) analysis. One of 67 raw whole lampreys (1.5%) was positive for the botulinum neurotoxin type E gene, with the estimated C. botulinum count being 100spores/kg. Two type E strains were isolated from the positive sample and confirmed as different genotypes by pulsed-field gel electrophoresis. Although the current procedure of bringing the charcoal-broiled lampreys to market has been without any further packaging or extended storage, interest towards increasing the shelf life of the product by vacuum-packaging is increasing. Our results demonstrate that C. botulinum type E may constitute a safety hazard in processed lampreys from the Baltic Sea area if packaging and extended shelf lives are to be used. To control the potential risk, a storage temperature of 3 degrees C or below should be recommended for these products.  相似文献   
27.
The effects of natural mixed diets on lipid peroxidation were investigated in humans. In the first study, 59 subjects were fed a rapeseed oil-based diet rich in monounsaturated fatty acids (MUFA) and a sunflower oil-based diet rich in polyunsaturated fatty acids (PUFA) in a cross-over manner for three and a half weeks. The lipid peroxidation products in plasma were determined by measuring conjugated dienes and malondialdehyde (MDA). In a second study, plasma thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides, and the susceptibility of very low density lipoprotein + low-density lipoprotein (LDL) toin vitro oxidation were measured from subjects fed similar MUFA and PUFA diets for six week diets. No significant differences in plasma MDA or conjugated diene concentrations were found after the rapeseed oil diet or the sunflower oil diet in Study 1. In the second study, a small but significant decrease (P<0.05) in both lipid hydroperoxides and TBARS was observed in the LDL fraction after the sunflower oil diet. Thein vitro oxidation gave opposite results, showing increased oxidation after the sunflower oil diet. Despite a high intake of α-tocopherol during the oil peroids, no increase in plasma α-tocopherol was noticed in either study. The results suggest that moderate changes in the fatty acid composition in the Western-type diet may be adequate to affect lipoprotein susceptibility to oxidationin vitro, but there is considerable disparity with some indices ofin vivo lipid peroxidation.  相似文献   
28.
Consumption of fossil fuel resources throughout the industrial era has resulted in an enormous increase in carbon dioxide concentration in the atmosphere. Developed countries have committed to reducing the atmospheric load of greenhouse gases and ratified the Kyoto Protocol. Chemical utilization of carbon dioxide captured from large scale stationary sources is one possible pathway to decrease the rate of emissions. Catalysis plays a crucial role in these carbon dioxide utilization reactions. In this paper, the production of synthesis gas from carbon dioxide-containing secondary gases and carbon dioxide hydrogenation to methanol over copper-based zirconia-containing catalysts have been investigated. Pathways of carbon dioxide utilization are outlined, research done on carbon dioxide hydrogenation over copper-based zirconia-containing catalysts is reviewed, and the challenges of these reactions are reported. It is argued that direct utilization of secondary carbon dioxide from industrial sources can be a significant step toward developing sustainable industrial practices and a critical part in sustainable energy strategies.  相似文献   
29.
BACKGROUND: Involuntary detrusor contractions often cause irritative symptoms such as urgency and incontinence. A dog model for acutely induced variable bladder outlet resistance was developed to investigate the possible role of prostatic afferent nerve fibers in the development and maintenance of detrusor instability. METHODS: Fifty-eight mongrel dogs (weight range 19.5-36.5 kg) were divided into five groups: group I (n = 11) had surgically induced bladder outlet obstruction. Group II (n = 14) had urinary obstruction and bilateral sectioning of the lowest branches of the pelvic plexus supplying the prostate. Group III (n = 10) had prostate denervation only. Groups IV (n = 10) and V (n = 13) were sham-operated and controls, respectively. In the obstructed groups (I and II), an artificial urinary sphincter (length 4.5-6.0 cm) was placed around the bladder neck and connected to a reservoir placed subcutaneously to allow postoperative adjustments of urinary resistance. All dogs were evaluated at baseline and postoperatively at 1, 3, and 6 months with uroflowmetry, postvoid residual urine volume, cystometry as well as serum creatinine, and urinalysis. RESULTS: Occurrences of detrusor instability were not associated with prostatic denervation input. The mean peak flow rates decreased significantly in the obstructed groups at all follow-ups, but did not change significantly in the nonobstructed groups. Postoperatively, the mean maximum bladder capacity was significantly decreased for groups I and II only. However, a significant correlation between maximum bladder capacity and maximum detrusor pressure could not be detected at any time point in any of the groups. Mean postvoid residual urine volume varied considerably in all groups over time. Creation of a urinary model of infravesical obstruction was associated with considerable problems. CONCLUSIONS: In our dog model of bladder outlet obstruction, prostatic sensory nerve fibers appear not to be involved in detrusor instability. Surgical induction of a constant model of bladder outlet obstruction was difficult even in a large animal. The observations from the present study raise questions about the validity of obstructive urinary animal models.  相似文献   
30.
Increased blood pressure and plasma cholesterol concentration are the major risk factors for cardiovascular diseases. We have previously shown that fermented milk products containing casein-derived bioactive tripeptides, isoleucine-proline-proline (Ile-Pro-Pro) and valine-proline-proline (Val-Pro-Pro) partly inhibit the blood pressure increase in spontaneously hypertensive rats (SHR). In the present study, we investigated the effect of bioactive tripeptide-containing fermented milk products (with or without plant sterols) on blood pressure and vascular function in salt-loaded type 2 diabetic Goto–Kakizaki (GK) rats after 8 weeks’ treatment. The development of blood pressure was attenuated in the groups receiving tripeptide-containing products (?10 to ?12 mmHg vs. the control product group, P < 0.01). Tripeptide-containing products enhanced the impaired endothelium-dependent relaxation of mesenteric arteries. Also the role of endothelium-derived hyperpolarizing factor (EDHF) was demonstrated. Interestingly, pretreatment of arterial rings with verapamil normalized the impaired endothelial function. Endothelium-independent relaxations were similar between the groups. Furthermore, tripeptides had positive effects on renin–angiotensin–aldosterone system.  相似文献   
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