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排序方式: 共有2041条查询结果,搜索用时 31 毫秒
31.
Marie D Sauro Randall S Jorgensen Craig K Ewart Jennifer L Schum Paul Gelling 《International journal of psychophysiology》2005,56(1):55-64
Although cardiovascular disease (CVD) remains the leading cause of mortality in women, few studies have examined the role of psychosocial factors in its development. This study examined the moderating effects of sociotropic cognition (SC), a need for social acceptance and approval, on psychosocial stress-induced cardiovascular responsiveness (CVR) and affect reactivity in women. Sixty-eight normotensive, college-aged females were randomly assigned to a low or high social threat condition. Measures of systolic, diastolic and mean arterial blood pressures (SBP, DBP and MAP, respectively), heart rate (HR), cardiac output (CO), total peripheral resistance (TPR) and negative affect were collected during rest, and under conditions of high vs. low interpersonal threat. A two-step hierarchical regression analysis was performed to predict all response variables (BPs, HR, CO, TPR and affect). Increases in SBP, DBP, MAP, TPR and negative affect were greater in the high threat than low threat condition. Changes in SBP, MAP and TPR positively covaried with SC under conditions of high interpersonal threat, but showed no significant covariation in the low threat condition. The data suggest that an excessive need for social acceptance may contribute to rises in BP through an increase in TPR, but not CO under conditions of high social threat. 相似文献
32.
DIFFERING EFFECTS OF CARBOHYDRATE, FAT AND PROTEIN ON THE RATE OF ETHANOL METABOLISM 总被引:2,自引:2,他引:0
ROGERS JO; SMITH JILL; STARMER G.A.; WHITFIELD J.B. 《Alcohol and alcoholism (Oxford, Oxfordshire)》1987,22(4):345-353
The rate of metabolism of ethanol in humans has been assessedby intravenous infusion of ethanol/saline under feedback controlto maintain a constant blood alcohol concentration. After equilibration,meals consisting predominantly of carbohydrate, fat or proteinwere eaten and changes in ethanol metabolic rate were found.Carbohydrate caused a significant increase in this rate andfat or protein caused small but non-significant decreases. Infusionof ethanol/saline resulted in a temporary fall in plasma freefatty acid levels and a steady rise in plasma triglycerides.The changes in alcohol metabolism following carbohydrate cannotbe accounted for by changes in insulin, free fatty acid or lactate/pyruvatelevels. 相似文献
33.
34.
Without a doubt, a supervisor's most valuable resources are the employees placed in trust with that supervisor. It is the challenge of every supervisor to focus the vast energies of this resource on accomplishing the mission of the organization. Within the context of new employees, what happens during those first days of employment may determine how well they will contribute, if at all, to accomplishing this organizational mission. While new employee assimilation has many factors that affect its success or failure, the nature of communication that occurs with the supervisor is critical. As was shown in this study, new employees do, in fact, have a specific set of communication needs of which the supervisor should be cognizant. 相似文献
35.
Changes in hemostasis after laparoscopic cholecystectomy 总被引:6,自引:3,他引:3
Martinez-Ramos C Lopez-Pastor A Nùñez-Peña JR Gopegui M Sanz-López R Jorgensen T Pastor L Fernandez-Chacon JL Tamames-Escobar S 《Surgical endoscopy》1999,13(5):476-479
Background: The aim of this work was to study hemostasis in laparoscopic cholecystectomy in order to determine if there are any changes
that indicate a greater risk of thrombosis.
Methods: The study was carried out in 20 patients who underwent laparoscopic surgery for noncomplicated cholelithiasis. The average
age was 59.4 years (range, 34–77). A total of 75% were female. Mean operation time was 70 min (ranges 35–120). Pneumoperitoneum
at 14 mmHg was performed on all patients, who were positioned in the 30° reverse Trendelenburg position. Postoperative mobilization
was acheived in 24 hs and patients were discharged 48 hs after the operation. The control group was composed of 12 patients,
who were evenly distributed by age, sex, and length of surgery. These patients underwent Bassini herniorraphy for inguinal
hernia without any complications or relapse. The following hemostatic parameters were studied: prothrombin activity (PA),
activated partial thromboplastin time (APTT), fibinogen (Fg), anti-thrombin III (ATIII), plasma fibrinolytic activity (PFA),
euglobulin fibrinolytic activity (EFA), and D-dimer (D-D). Samples were obtained at the following times: (a) under basal conditions
the day before surgery, (b) preoperatively, (c) at the end of the operation, (d) 24 hs after the operation, and (e) On the
7th day following the operation.
Results: No patient showed any clinical manifestations of thromboembolic disease immediately after surgery or during a medium follow-up
period of 16 months (range, 15–18 months). All hemostatic parameters values were within normal range in the basal samples
of both groups. In both groups, the mean value of PA showed a significant decrease (p < 0.05) in the second, third, and fourth basal samples, returning to normal levels by the fifth determination. The mean value
of fibrinogen decreased slightly in the second and third samples, increasing significantly with respect to the fourth and
fifth determinations in both groups (p < 0.05). The mean value of APTT in both groups was slightly enhanced in the second and third determinations in relation to
the first and fifth. The global activity of fibrinolysis (PFA and EFA) increased significantly in the third sample with respect
to the other determinations in the group who had laparoscopic surgery (p < 0.005). Only EFA increased in the control group (p < 0.05). D-D decreased in the preoperative second determination followed by a significant enhancement immediate postoperatively
(third), and 24 hs (fourth) (p < 0.05); it returned to normal basal values on the seventh day. No significant differences were found between the two groups.
Conclusions: These results indicate that laparoscopic cholecystectomy leads to no greater activation of plasma coagulation than low-risk
surgery. On the contrary, the increase of fibrinolytic activity in plasma would extend a certain degree of hypocoagulability
during surgery, maintaining it for 24 hs and thus possibly reducing thromboembolic risk in patients undergoing this type of
surgery.
Received: 25 February 1998/Accepted: 18 August 1998 相似文献
36.
OBJECTIVE: To assess the influence of smoking on serum parathyroid hormone (PTH), serum vitamin D metabolites, serum ionized calcium, serum phosphate, and biochemical markers of bone turnover in a cohort of 510 healthy Danish perimenopausal women. DESIGN: A cross-sectional study. SETTING: Copenhagen, Denmark. SUBJECTS: Five-hundred-and-ten healthy women aged 45-58 y, included 3-24 months after last menstrual bleeding. None were using hormone replacement therapy. METHODS: The women were grouped according to their current smoking status. The two groups were compared with regard to serum levels of 25-hydroxyvitamin D (25OHD) and 1, 25-dihydroxyvitamin D (1,25-(OH)2D), intact PTH, ionized calcium and phosphate, osteocalcin, as well as urine pyridinolines. Bone mineral density (BMD) was measured with DEXA-scans. Multiple regression analyses were performed to detect the effect of potentially confounding lifestyle factors, such as calcium and vitamin D intakes, alcohol and coffee consumption, sunbathing, and physical exercise. RESULTS: Fifty percent were current smokers. Smokers had significantly reduced levels of serum 25OHD (P=0.02), 1,25(OH)2D (P=0.001), and PTH (P<0.001). There was no difference in serum ionized calcium between smokers and non-smokers. We found a negative effect of smoking on serum osteocalcin (P=0.01), while urinary pyridinolines were similar in the two groups. The small differences in lifestyle between the two groups could not explain these findings. Smokers had small but significant reductions in bone mineral density. CONCLUSIONS: Smoking has a significant effect on calcium and vitamin D metabolism, which is not likely to be explained by other confounding lifestyle factors. The depression of the vitamin D-PTH system seen among smokers may represent another potential mechanism for the deleterious effects of smoking on the skeleton, and may contribute to the reported risk of osteoporosis among smokers. Sponsorship: Grants from the Karen Elise Jensens Foundation. 相似文献
37.
PURPOSE: To examine the individual and organizational health effects of HIV/AIDS interventions conducted at the worksite. SEARCH METHODS: This review is part of a series of reviews that used search methods described in an introductory article. To supplement these methods, HIV/AIDS-specific periodicals were searched to include journals that might not be incorporated in the computerized databases. Twelve of the 20 articles identified through the Centers for Disease Control and Prevention and our own subsequent searches met the criteria and were included in this review. FINDINGS: Ten of the 12 studies reviewed reported positive effects of employee education programs on knowledge or attitudes. Nine of the studies involved health care workers or employees with potential occupational exposure to HIV, and nine lacked a comparison or control group. None of the studies however, examined the effects of policies, manager training, or family education on the organization or person. CONCLUSIONS: Methodologic weaknesses in many of the studies reviewed, coupled with the small number of studies, led us to conclude that the research literature on worksite HIV/AIDS interventions is weak. Impact is, however, plausible. Future research should be directed toward developing valid measures of key variables, controlling for confounding factors, and ultimately examining the impact of organizational factors. 相似文献
38.
S A Oliveria M Saraiya A C Geller M K Heneghan C Jorgensen 《Archives of disease in childhood》2006,91(2):131-138
BACKGROUND: As skin cancer education programmes directed to children and adolescents continue to expand, an epidemiological basis for these programmes is necessary to target efforts and plan for further evaluation. AIMS: To summarise the epidemiological evidence on sun exposure during childhood and adolescence and melanoma risk. METHODS: A literature review was conducted using Medline (1966 to December 2004) to identify articles relating to sun exposure and melanoma. The review was restricted to studies that included sun exposure information on subjects 18 years of age or younger. RESULTS: Migrant studies generally indicate an increased melanoma risk in individuals who spent childhood in sunny geographical locations, and decreasing melanoma risk with older age at arrival. Individuals who resided in geographical locations close to the equator or close to the coast during childhood and/or adolescence have an increased melanoma risk compared to those who lived at higher latitudes or never lived near the coast. The intermittent exposure hypothesis remains controversial; some studies indicate that children and adolescents who received intermittent sun exposure during vacation, recreation, or occupation are at increased melanoma risk as adults, but more recent studies suggest intermittent exposure to have a protective effect. The majority of sunburn studies suggest a positive association between early age sunburn and subsequent risk of melanoma. CONCLUSION: Future research efforts should focus on: (1) clarifying the relation between sun exposure and melanoma; (2) conducting prospective studies; (3) assessing sun exposure during different time periods of life using a reliable and quantitative method; (4) obtaining information on protective measures; and (5) examining the interrelations between ability to tan, propensity to burn, skin type, history of sunburns, timing and pattern of sun exposure, number of nevi, and other host factors in the child and adolescent populations. 相似文献
39.
Charles E. Hendrick Jeff R. Jorgensen Charu Chaudhry Iulia I. Strambeanu Jean-Francois Brazeau Jamie Schiffer Zhicai Shi Jennifer D. Venable Scott E. Wolkenberg 《ACS medicinal chemistry letters》2022,13(7):1182
A platform to accelerate optimization of proteolysis targeting chimeras (PROTACs) has been developed using a direct-to-biology (D2B) approach with a focus on linker effects. A large number of linker analogs—with varying length, polarity, and rigidity—were rapidly prepared and characterized in four cell-based assays by streamlining time-consuming steps in synthesis and purification. The expansive dataset informs on linker structure–activity relationships (SAR) for in-cell E3 ligase target engagement, degradation, permeability, and cell toxicity. Unexpected aspects of linker SAR was discovered, consistent with literature reports on “linkerology”, and the method dramatically speeds up empirical optimization. Physicochemical property trends emerged, and the platform has the potential to rapidly expand training sets for more complex prediction models. In-depth validation studies were carried out and confirm the D2B platform is a valuable tool to accelerate PROTAC design–make–test cycles. 相似文献
40.
Patient‐ and family‐centred care in the intensive care unit: a challenge in the daily practice of healthcare professionals
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