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排序方式: 共有986条查询结果,搜索用时 31 毫秒
1.
Suyen Karki Eila Laukkanen Helena Länsimies Tomi-Pekka Tuomainen Anna-Maija Pietilä 《Journal of substance use》2019,24(3):300-308
Background: Research has demonstrated that problem behavior has been associated with substance use, but knowledge is lacking on such associations in a low-income country like Nepal. Aims: This study aimed to find associations between emotional and behavioral problems and substance use among Nepalese adolescents. Method: A cross-sectional study was conducted at the end of 2011, with participants from three schools in the Province 4 of Nepal. We selected 408 adolescents aged 12 to 18 (mean 15.2 years, 54% boys) at one urban and two rural schools. The data were collected using the Youth Self-Report and Adolescents’ Substance Use Measurement. Results: Higher scores on withdrawn/depressed symptoms, thought problems, attention problems, delinquent or aggressive behavior or internalizing or externalizing problems were associated with the use of tobacco, alcohol or other substances. In the broadband scales, only internalizing problems predicted the use of intoxicants. Higher scores for attention problems predicted the use of tobacco, any intoxicants, and high-risk user. Conclusion: Our findings indicated that problem behavior among Nepalese adolescents was associated with substance use. Future studies should explore the association between problem behavior and substance use, including causal factors, so that risky behavior among Nepalese adolescents can be prevented. 相似文献
2.
We studied the parathyroid function in patients with advanced renal failure by determining their plasma concentrations of ionized calcium (iCa), intact parathyroid hormone (PTH) and its inactive metabolites (PTH-MM). The suppressibility of the parathyroidism was studied with a calcium infusion test. The intact PTH values of the nondialysis and dialysis patients did not statistically differ from each other. The concentrations of PTH-MM were, however, higher in the dialysis patients than in the nondialysis patients (p less than 0.05). The ratio of PTH-MM to intact PTH was lowest in healthy reference subjects and highest in dialysis patients (p less than 0.01), and did not correlate with the degree of intact PTH elevation in the patient groups. The calcium infusion test was carried out on 15 patients. All showed suppression in the elevated plasma intact PTH concentration and in 6 the intact PTH value normalized. The PTH-MM value did not normalize in any of the patients. During oral calcium treatment the degree of intact PTH suppression at an achieved concentration of plasma iCa was predictable from the infusion test. Three patients were parathyroidectomized after the calcium infusion test. In 2 of these elevated intact PTH normalized within 24 h while in 1 no change took place. In this latter case on clinical improvement was noted. We conclude that the determination of plasma intact PTH concentration especially of combined with plasma iCa value is a reliable means of studying the hyperparathyroidism associated with chronic renal failure. 相似文献
3.
Markku Walamies Vesa Virtanen Matti Koskinen Arto Uusitalo 《European journal of nuclear medicine and molecular imaging》1994,21(9):968-972
The decrease in mortality among patients receiving thrombolytic therapy for myocardial infarction is greater than would be expected from the improvement in left ventricular contractile function alone; thus some additional advantage of recanalization of the infarctrelated coronary artery probably exists. Changes in the post-infarction myocardial metabolic state with respect to artery patency have not been studied with a gamma camera previously. A single-photon emission tomography scan using the fatty acid analogue para-123I-iodophenylpentadecanoic acid was performed at rest before hospital discharge on nine patients with first anterior myocardial infarction. All patients had received intravenous thrombolytic therapy at the beginning of the insult. The semiquantitative analysis of the left ventricle included a total of 44 segments in each patient. The test was repeated 3 months later, with the patients divided into two groups: six patients had an angiographically patent left anterior descending coronary artery (group A), and three an occluded artery (group B). In group A the number of myocardial segments with abnormal (<70% of maximum) fatty acid uptake was initially 20.2±4.7 (mean±SD) and was reduced to 11.3±6.1 during the follow-up (95% confidence interval of the decrease 16.0–1.7 segments). In group B the number of these aberrant segments was fairly constant (21.7±13.1, initial test, and 21.3±13.3, retest). Our preliminary results suggest that even when thrombolytic therapy fails to prevent myocardial infarction, myocardial fatty acid metabolism has a better change of recovering if the relevant coronary artery has regained its patency. This finding emphasizes the need for further study to establish whether a direct link exists between myocardial metabolic state and patient survival after infarction. 相似文献
4.
Incidence, nature, and causes of ice hockey injuries. A three-year prospective study of a Swedish elite ice hockey team 总被引:2,自引:0,他引:2
In this prospective study, we have investigated incidence of injuries of different severity, types of injury, and mechanisms of injury during ice hockey practice and games. One Swedish elite hockey team was closely observed during three seasons (1982 to 1985). There was a total number of 95 injuries and 29 facial lacerations. The majority of injuries were minor (73%) and only 8% were classified as major. Seventy-six percent of the injuries occurred during games and 24% during practice. The incidence of injury during practice was 1.4 per 1,000 player-practice hours and 78.4 per 1,000 player-game hours. In comparison with other sports, the incidence of injury during hockey practice is very low, while that during games is high. Eighty percent of the injuries were caused by trauma and 20% by overuse. The most common types of injury were contusions, strains, and sprains. Complete tear of the medial collateral ligament of the knee was the most common severe injury. Most injuries resulted from body contact, predominantly tackling (checking), and from puck or stick contact. A reduction of the number of minor and moderate injuries should be possible by stricter enforcement of the hockey rules, especially against stick violations, and more widespread use of visors. 相似文献
5.
6.
Markku Leino MD Kalevi Pyörälä Seppo Lehto Arto Rantala 《Documenta ophthalmologica. Advances in ophthalmology》1992,80(4):309-315
Lens opacity studies were performed using an electronic Lens Opacity Meter (Interzeag Opacity Lensmeter 701) in a population (n = 321) with ischaemic heart disease. These patients are participating in a trial targetting at the reduction of mortality and incidence of myocardial infarction using a cholesterol-lowering drug, simvastatin. A separate study to evaluate the reliability of the method showed good reproducibility. Repeated measurements after a short time-interval (2–10 days) gave statistically lower opacity values either due to a change in lens transparency or perhaps a change in pigment and cell dispersion in the acqueous caused by repeated mydriasis. Lens opacity values showed a highly significant positive correlation to age. Serum cholesterol, systolic blood pressure and smoking habits showed no significant correlations to the levels of lens opacity when adjustments for age were made.Abbreviations HMG-CoA
hydroxy-methylglutarylcoenzyme A
- 4S
Scandinavian Simvastatin Survival Study
- LOM
lens opacity meter 相似文献
7.
Arto J. Turunen José A. Fernández Leena Lindgren Kaija T. Salmela Lauri E. Kyllönen Heikki Mäkisalo John H. Griffin Sanna M. Siitonen Jari Petäjä Eero J. Pesonen 《American journal of transplantation》2005,5(9):2204-2212
We studied the role of endogenous activated protein C (APC), the major physiological anti-coagulant with concomitant anti-inflammatory properties, on ischemia/reperfusion (I/R) in 45 patients participating in a larger trial comparing three immunosuppressive protocols in cadaveric renal transplantation: perioperative anti-thymocyte globulin (ATG, Fresenius AG, Bad Homburg, Germany), perioperative basiliximab and conventional triple therapy. Blood samples for assessing plasma APC, protein C, and lactoferrin concentrations, neutrophil CD11b and L-selectin expressions and blood leukocyte differential counts were obtained preoperatively and before reperfusion from central venous cannula, complemented with simultaneous samples from iliac artery and graft vein for calculation of transrenal differences (Delta) of study parameters at 1 and 5 min after reperfusion. Unlike basiliximab or conventional therapy groups, ATG infusion induced a substantial increase in plasma APC concentration (119 [88-144]% before infusion vs. 232 [85-1246]% after infusion, p<0.001), resulting in renal graft sequestration of APC at 1 min after reperfusion (Delta=-72 [-567 to 12]%, p<0.001). Graft APC consumption was associated with transrenal reduction of neutrophil activation markers (L-selectin r=0.7, p=0.01; lactoferrin r=-0.6, p=0.02; CD11b r=-0.8, p=0.001), and with both warm (r=0.6, p=0.01) and cold ischemia time (r=0.6, p=0.02) and donor age (r=0.6, p=0.01). These findings suggest that APC has an anti-inflammatory role in I/R injury in clinical renal transplantation. 相似文献
8.
J P Pietil? 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》1990,24(2):135-140
The skin circulation was examined in nine patients during filling of their breast expander prostheses. Despite the high expansion pressure, which was increased above the systolic blood pressure, the overlying skin showed good circulation both clinically and when measured with a laser Doppler flowmeter and a transcutaneous oximeter. We conclude that the expansion was therefore directed to the tissues between the expander and the skin--that is, the fibrous capsule surrounding the prosthesis. Nine subcutaneous tissue expanders located in different anatomical regions were overfilled to a pressure at which all skin circulation ceased. Sufficient saline was then removed to allow skin circulation to return. Oxygenation of the skin ceased at a relatively low pressure when measured by transcutaneous oximetry, whereas when the skin circulation was measured with a laser Doppler flowmeter it did not disappear until the expander pressure had been raised appreciably above that level. 相似文献
9.
We have earlier introduced a principle for learning metrics, which shows how metric-based methods can be made to focus on discriminative properties of data. The main applications are in supervising unsupervised learning to model interesting variation in data, instead of modeling all variation as plain unsupervised learning does. The metrics are derived by approximations to an information-geometric formulation. In this paper, we review the theory, introduce better approximations to the distances, and show how to apply them in two different kinds of unsupervised methods: prototype-based and pairwise distance-based. The two examples are self-organizing maps and multidimensional scaling (Sammon's mapping). 相似文献
10.
This study examined the phenomenon of acute tolerance to ethanol (ETOH) using drug discrimination learning (DDL), and open-field (OF) procedures. In DDL, rats were trained to discriminate between ETOH (1.2 g/kg) and saline. Doses of ETOH lower (0.6 and 0.9 g/kg), or higher (1.8 and 2.4 g/kg) than the training dose were tested to examine possible influence of ETOH pretreatment doses on the expression of acute tolerance. To assess concentrations of ETOH in the organism, a rebreathed air procedure was used. Equal concentrations after different ETOH doses were achieved by postponing the tests until sufficient time had elapsed. Only doses of ETOH higher than the training dose produced acute tolerance in the DDL procedure. For the response-time data no acute tolerance was observed. In the OF experiment, the occurrence of acute tolerance was examined for different spontaneous behaviours in drug-naive animals. At equal ETOH concentrations, the group examined during the descending phase of intoxication (1.8 g/kg, 60 min post-injection), reared significantly more than the group tested during the ascending phase (1.5 g/kg, 10 min post-injection). Other OF behaviours did not differ significantly between the two time intervals. Thus, it is suggested that acute tolerance is seen both in ETOH naive and in ETOH pre-exposed rats. However, in DDL acute tolerance was observed only when doses higher than the training dose of ETOH were evaluated. 相似文献