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排序方式: 共有531条查询结果,搜索用时 15 毫秒
31.
Koposov RA Ruchkin VV Eisemann M Sidorov PI 《Alcohol and alcoholism (Oxford, Oxfordshire)》2002,37(3):297-303
Drinking alcohol is an essential and commonplace part of life in Russia. Alcohol-related problems in the general population and among adolescents in particular has become a major public health concern. The problem cannot be solely explained by the frequency and quantity of alcohol consumption. The social determinants of drinking alcohol also need to be considered. These are the focus of the present investigation. The social determinants of drinking behaviour were assessed by self-reports (Social Context of Drinking Scale, Adolescent Alcohol Involvement Scale and Rutgers Alcohol Problem Index) in 387 secondary school students in Arkhangelsk, Russia. The factor structure for the Social Context of Drinking Scale was similar to that noted in respect of the original study [Thombs and Beck (1994) Health Education and Research 9, 13-22]. Significant gender differences in problem drinking and the social contexts of drinking were found. High intensity girl drinkers were likely to drink in most social contexts, whereas high intensity drinking boys were more likely to drink in the context of Stress Control. Furthermore, boy problem drinkers were more likely to drink in the context of School Defiance and Peer Acceptance, whereas girl problem drinkers tended to drink in the contexts of School Defiance and Stress Control. In general, the Social Context of Drinking Scale demonstrated a good ability to discriminate high from low intensity drinkers, and high from low problem drinkers. These results may provide useful information for targeted prevention programmes for adolescents. 相似文献
32.
Mikić D Bojić I Djokić M Stanić V Stepić V Mićević D Rudnjanin S Radosavljević A Mićić J Tomanović B Begović V Popović S 《Vojnosanitetski pregled. Military-medical and pharmaceutical review》2002,59(2):203-207
The first case of the confirmed necrotizing fasciitis caused by Group A Streptococcus in Yugoslavia was presented. Male patient, aged 28, in good health, suddenly developed symptoms and signs of severe infective syndrome and intensive pain in the axillary region. Parenteral antibiotic, substitutional and supportive therapy was conducted along with the radical surgical excision of the necrotizing tissue. The patient did not develop streptococcal toxic shock syndrome thanks to the early established diagnosis and timely applied aggressive treatment. He was released from the hospital as completely cured two months after the admission. 相似文献
33.
Cell cultures were derived from adult human brain biopsies [from cortical gray (cultures 9-HB-G and 33-HB-G) and white (culture 14-HB-W) and stroke-injured white matter (culture 33-HB-IW)]. The morphology and growth rate of cultured cells were examined and correlated with the presence of vimentin and glial fibrillary acidic protein (GFAP). The cultures from various brain matters differed in cell morphology and rate of growth but not in GFAP and vimentin staining. Cells of primary and rapidly proliferating cultures were GFAP-negative and vimentin-positive. Spontaneous growth deceleration occurred in culture 14-HB-W within passages 5 to 10 and in cultures 9-HB-G, 33-HB-G, and 33-HB-W within passages 17 to 20. This deceleration, as well as the successive complete growth arrest, were accompanied by an appearance of GFAP-positive cells and an elevated intensity for vimentin staining. We propose that GFAP-positive astrocytes originate from glial precursor cells that migrate from the explants and differentiate under prolonged subcultivation. 相似文献
34.
Bachar GN Shafir G Postnikov V Belenky A Benjaminov O 《Journal of clinical ultrasound : JCU》2005,33(2):76-79
PURPOSE: The purpose of this study was to identify the characteristic features of omental infarction so that this entity can be differentiated from other acute conditions in the right lower quadrant of the abdomen. METHODS: A retrospective review was undertaken. We searched our hospital medical records and found 6 patients with the diagnosis of omental infarction in the last 3 years. Clinical, sonographic, and CT findings at the time of hospital admission and at follow-up were studied. RESULTS: In 5 of the 6 patients (83%) sonography demonstrated a moderately hyperechoic, noncompressible ovoid mass located in the omental fat between the umbilicus and the right colon corresponding to the point of maximal tenderness or to the site of a palpable lesion on physical examination. In 1 patient, sonography revealed no abnormalities. In all patients, the diagnosis of omental infarction was confirmed by CT. One patient underwent laparoscopy because of intractable pain; laparoscopy revealed a necrotic segment in the omentum, and pathologic analysis confirmed the original diagnosis. CONCLUSIONS: Omental infarction is a benign self-limited disease that can mimic acute abdomen. The diagnosis can be established preoperatively with sonography and CT, which may avoid unnecessary laparotomy. 相似文献
35.
Martin A Ruchkin V Caminis A Vermeiren R Henrich CC Schwab-Stone M 《Journal of the American Academy of Child and Adolescent Psychiatry》2005,44(4):358-367
OBJECTIVE: To examine the association between sexual activity among urban adolescent girls and four global measures of psychosocial adaptation (academic motivation, school achievement, depressive symptoms, and expectations about the future). METHOD: Data derived from the Social and Health Assessment, a self-report survey administered in 1998 to students in the public school system in New Haven, CT (149 classes at 17 middle and high schools). RESULTS: Of 1,413 respondents (57% black, 28% Hispanic; mean age 13.4 +/- 1.7 years), 414 (29%) acknowledged prior sexual intercourse; the proportions of sexually active girls in 6th, 8th, and 10th grades were 14%, 30%, and 50%, respectively. In multivariate analyses of covariance, sexual activity was significantly associated with all four measures of psychosocial adaptation (p < .001). Other correlates of at least one measure of maladaptation included socioeconomic status, sensation seeking, and lower school grade (p < .001 for each), peer pressure (p < .01), and black ethnicity, and the interaction of sexual activity by lower school grade (p < .05 for each). CONCLUSIONS: Compared with their sexually naive peers, sexually active adolescent girls had lower scores on global measures of psychosocial adaptation. These findings have clinical, policy, and research relevance to a vulnerable population at high risk of teenage pregnancy and sexually transmitted diseases. 相似文献
36.
Vermeiren R Jones SM Ruchkin V Deboutte D Schwab-Stone M 《Journal of child psychology and psychiatry, and allied disciplines》2004,45(3):567-576
BACKGROUND: Cross-national studies describing the psychopathological characteristics of arrested adolescents are virtually non-existent. Such studies are important because they have implications for national policy on arrest, case-management, and future research. METHOD: To address this issue, self-report surveys administered to representative groups of 12- to 16-year-old adolescents in New Haven, USA (N = 1138) and Antwerp, Belgium (N = 627) were compared. A number of internalizing and deviant behavior variables were compared between controls (C), non-arrested antisocial (NA), and arrested antisocial (AR) participants. RESULTS: Similar cross-national arrest rates and levels of antisocial behavior were found. NA and AR youths in both countries reported more internalizing problems, except for anxiety, and more deviant characteristics. Contrary to expectations, the level of depression was not higher in AR compared to NA youth when differences in antisocial behavior between NA and AR were controlled. Also unexpected, arrest showed an independent association with a number of deviant behavior variables. CONCLUSIONS: Further research should investigate the underlying mechanisms of these associations, as this insight would be useful for developing future intervention and prevention programs, as well as for developing future national policies regarding juvenile antisocial behavior. 相似文献
37.
We have synthesised some of 2-substituted 4-(3H)-quinazolones by the reaction with benzaldehyde and cinnamic aldehyde and their derivatives. It is shown that the intensity of the reaction depends on electrophilic properties of carbonyl compounds and steric factors. The elemental analysis, ultraviolet (UV), infrared (IR) and nuclear magnetic resonance (NMR) spectroscopy confirmed the structure of synthesised compounds, their individuality being checked by thin-layer chromatography. The results of biological experiments show that the synthesised 2-substituted 4-(3H)-quinazolones have an expressed antioxidant and antiamnestic activity and are prospective for further research of their nootropic activity. 相似文献
38.
Vladislav Nodelman Harihara Baskaran James S. Ultman 《Annals of biomedical engineering》1998,26(6):1044-1054
An intravascular gas exchange device for the treatment of respiratory failure consisted of a multitude of blind-ended hollow fibers glued in a pine-needle arrangement to a central gas supply catheter. It has previously been shown that gas desorption rates can be significantly enhanced by cycling gas pressure between a hypobaric level of 130 and an ambient level of 775 Torr. In this study, influences of the cycling frequency (f) and the cycle fraction during which hypobaric pressure is applied () were investigated. Rates of O2 desorption from O2-saturated water and CO2 desorption from CO2-saturated water into a manifold containing 198 fibers, 380 m in diameter, were measured over a range of f from 0.2 to 1.0 Hz, from 0.1 to 0.8, and fiber lengths from 4 to 16 cm. Relative to operation at ambient pressure, pressure cycling increased O2 transfer 3–4 times and CO2 transfer 4–6 times when the water flowed over the fiber manifold at 2.3 l/min. Transfer rates were relatively insensitive to f and with 80–90% of maximum enhancement obtained when was as low as 0.2. Transfer rates increased continuously with fiber length, implying that pressure cycling reduced the intra-fiber resistance to gas diffusion. A mathematical diffusion model which utilized only two adjustable parameters, a mass transfer coefficient for O2 and for CO2, simulated the trends exhibited by desorption data. © 1998 Biomedical Engineering Society.
PAC98: 8745Hw, 8790+y 相似文献
39.
Mikhail L. Lobanov Vladislav A. Khotinov Vladimir N. Urtsev Sergey V. Danilov Nikolay V. Urtsev Sergey I. Platov Stepan I. Stepanov 《Materials》2022,15(2)
Thermo-mechanical controlled processing (TMCP) is employed to obtain the required level of mechanical properties of contemporary HSLA steel plates utilized for gas and oil pipeline production. The strength and crack resistance of pipeline steels are mainly determined by its microstructure and crystallographic texture. In this study, the influence of the structural and textural states of industrially produced API-5L X70-X80 pipeline steels on tensile mechanical properties was analyzed. TMCP routes with different hot rolling temperatures and cooling rates were employed. The texture of steel was assessed using the Taylor factor, which was calculated based on electron backscatter diffraction (EBSD). The decrease in rolling temperature resulted in the sharper texture characterized by {001} planes banding (cleavage planes in the bcc lattice) parallel to rolling direction. The tensile deformation behavior at the stage of necking was determined by the crystallographic and morphological texture of the material and demonstrated significant anisotropy. Rupture of all investigated samples was accompanied by the development of splitting on the fracture surface. The splitting was localized in the rolling plane similar to the splitting in standard Charpy tests of pipeline steels. 相似文献
40.
Ibolja Cernak Jovan Savic Gordana Zunic Nada Pejnovic Olivera Jovanikic Vladislav Stepic 《World journal of surgery》1999,23(1):44-53
n
= 665, 51%)
had an ISS ranging from 0 to 34 (mean 13) had wounds ranging from G1ST
(soft tissue wounds caused by low energy transfer) to G3VF (massive
wounds with fractures and injury of vital structures) according to the
RCWC, with PSS/IS scores from 2 to 105 (mean 60). Statistically
significant correlation was found between ISS and PSS/IS as well as
RCWC and PSS/IS. Cytokines (IL-1, TNF
alpha
) and amino acids
responded to a blast injury in similar manner as to gunshot wounds with
a greater ISS or more severe RCWC injury type. The subjective
sensations in blasted patients (deafness, thoracic pain, vertigo) and
mediators, confirmed in previous experimental investigations as
important factors in the pathogenesis of blast injuries
(TxA
2
, sulfidopeptide leukotrienes) were relationed only to
the PSS/IS.RID=" ID=" <E5>Correspondence to:</E5> I. Cernak, M.D., Ph.D. 相似文献