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排序方式: 共有7661条查询结果,搜索用时 15 毫秒
1.
Megan A. O’Grady Kristina Wilson Jennifer J. Harman 《The journal of primary prevention》2009,30(6):716-731
The purpose of this study was to evaluate a single-session peer-led safer sex intervention, based on the Information-Motivation-Behavioral
Skills theoretical model, for college students residing in campus residence halls. Participants (N = 108) were assigned to either an hour long control or 5-module intervention session. Compared to the control condition,
the intervention increased participants’ information and women’s subjective norms about preventative behavior. Both the control
and intervention sessions increased intentions to perform preventative behaviors (e.g., keep condoms available). These preliminary
results suggest that this intervention is promising for increasing constructs associated with safer sexual behavior and could
easily be implemented by residence hall staff. 相似文献
2.
Man Bok Jeong Kristina Narfström Shin Ae Park Je Min Chae Kang Moon Seo 《Documenta ophthalmologica. Advances in ophthalmology》2009,119(2):79-88
The objective of this study is to compare the effects of three different anesthetic combinations on the electroretinogram
in the same animals under similar laboratory conditions. Thiopental–isoflurane (TI), medetomidine–ketamine (MK), and xylazine–ketamine
(XK) were used on each of 12 healthy miniature schnauzer dogs (MS) with a period of at least 3 weeks in between subsequent
anesthesia protocols, using the Dog Standard Protocol. The scotopic ERGs consisted of scotopic low stimulus strength (S) responses
designated S1, S2, S3, S4, and S5, at 1, 5, 10, 15, and 20 min after dark adaptation, respectively, and scotopic standard
stimulus strength (S-ST) responses. The photopic ERGs consisted of a photopic single flash (P) response and 31 Hz flicker
(P-FL) responses. For S-ST (2.5 cd s/m2), the amplitude of the a-wave using TI was significantly lower than that using MK (adjusted P = 0.05) and XK (adjusted P = 0.03), and the implicit time of the a-wave was significantly shorter than that using MK (adjusted P = 0.04). For P (2.5 cd s/m2), the amplitude of the b-wave using XK was significantly higher than that using MK (adjusted P = 0.01). The implicit times of the b-wave using TI was significantly longer and shorter than that of MK for S1, S2 and P-FL
and for S4 and S-ST, respectively, and than that of XK for S2 and P-FL and for S5 and S-ST, respectively. The results of the
present study showed that TI affected both the amplitude and the implicit time of the a-wave for S-ST and the implicit time
of the b-wave relatively more so than was the case when using XK or MK. Therefore, it appears that either XK or MK could be
advantageous to use rather than TI for clinical studies. 相似文献
3.
4.
Helmut Seidel Barbara Harazin Kristina Pavlas Christine Sroka Jörg Richter Ralph Blüthner Udo Erdmann Jan Grzesik Barbara Hinz Reinhard Rothe 《International archives of occupational and environmental health》1988,61(1-2):95-106
Summary This study was carried out in order: (1) to examine the effects of isolated and combined prolonged exposures to noise and whole-body vibration on hearing, vision and subjectively experienced strain, and (2) to check the combined effects with repeated exposures. Six male subjects were exposed twice to noise (N) at 92 dBA, whole-body vibration (V) in the Z-axis at 4 Hz and 1.0 ms–2 rms, and noise and vibration (NV) for 90 min with each condition. Temporary threshold shifts of hearing (TTS) and their integrals (ITTS) were measured at 4, 6, 10, and 12 kHz. Visual acuity was examined by means of a very sensitive test. Cross-modality matching (CMM) of the handgrip force was used to judge the subjectively experienced strain. NV induced a clear tendency of higher TTS and ITTS than N, with several significant differences most pronounced at 10 kHz. With repeated exposures, the effect of NV decreased, while the reactions to N and V remained unchanged. The individual reactions to NV differed. The influence of the duration of exposures on vision depended on the condition; N caused time-dependent changes, whereas V did not. CMM-data increased with the duration of the exposure during V and NV. N was generally judged to be more straining than V; NV caused higher strain than V during the first 30 min of exposure only. Correlations between different effects suggest certain links between them. Additionally, less motivation — daily obtained by a questionnaire — often correlated with higher ITTS during N and NV. The results also illustrate the combined effects on the individual susceptibility, repetition of exposure, the kind of response, and, possibly, the actual psychic state.Abbreviations CMM
cross-modality matching
- MVC
maximum voluntary contraction force
- N
exposure condition: noise level 92dBA, no whole-body vibration
- NV
exposure condition: combined exposure to noise with a level of 92 dBA and wholebody vibration with 4 Hz, 1 ms–2 rms
- V
exposure condition: whole-body vibration with 4 Hz, 1 ms–2 rms
- TTS
temporary threshold shift
- ITTS
integral of temporary threshold shift
- WBV
whole-body vibration in the common sense
This work was done in the Temporary International Research Team on Combined Effects of Noise and Vibration of the Council of Mutual Economic Assistance of the Socialist Countries. The authors gratefully acknowledge the help and assistance of L.-M. Brumm, Y. Bening, M. Godau, G. Weber, and R. Vizcaino. 相似文献
5.
E Kinnunen M Ojala H Taskinen E Matikainen 《Scandinavian journal of work, environment & health》1988,14(5):332-333
A truck driver was injured by a high-voltage line of 10,000 volts when holding a metallic bar in both hands. Initially no neurological abnormalities were found, but during the following few weeks increasing sensory and minor motor symptoms developed in the right upper extremity. After one year numbness of the right thigh and leg appeared, as well as attacks of white finger in both hands. Repeated examinations showed progressive abnormalities of the median and ulnar nerves in both hands. No other cause for Raynaud's syndrome was discovered. The late high-voltage effects, presumably indirect, are suggested to be of multifactorial etiology. 相似文献
6.
Association of human polyomavirus JC with peripheral blood of immunoimpaired and healthy individuals
Drries Kristina Sbiera Silviu Drews Klaus Arendt Gabriele Eggers Christian Drries Rdiger 《Journal of neurovirology》2003,9(1):81-87
JC virus (JCV) infection is regularly asymptomatic in healthy individuals. In contrast, in immunocompromised individuals, highly activated virus replication may lead to PML. Peripheral blood cells (PBCs) are found to habor JCV DNA in healthy and diseased individuals and it is discussed that they might be responsible for dissemination of the virus to the central nervous system (CNS) during persistence. To better understand the role of JCV DNA in PBCs for persistent infection and pathogenesis, the authors characterized the extent of JCV infection in Ficoll-gradient purified blood cells (peripheral blood mononuclear cells [PBMCs]) of healthy and human immunodeficiency virus type 1 (HIV-1)-infected individuals. Virus activation in PBMCs from healthy JCV-infected individuals was found at a rate of 0% to 38% at low polymerase chain reaction (PCR) sensitivity. In progressive multifocal leukoencephalopathy (PML) patients, a stronger signal was found, indicating increased virus activation. JCV DNA was regularly detected in T and B lymphocytes and in monocytes at low levels. However, granulocytes were shown to be the predominant reservoir of JCV DNA harboring high copy numbers. Although the overall distribution of viral genomes holds true for the population studied, in the individual, a markedly changed pattern of distribution can be found. 相似文献
7.
J Kinnunen 《Acta radiologica (Stockholm, Sweden : 1987)》1988,29(4):395-399
Image quality in radiography of midfacial trauma was studied in 618 patients treated for midfacial injury. The visibility of key anatomic areas was related to essential technical factors influencing image quality as well as to the radiologic diagnostic performance. Regression analysis revealed that the visibility of the key anatomic areas was significantly dependent on the technical factors. However, the radiologic diagnostic performance was not significantly dependent on the visibility of the key anatomic areas. The results indicate that image quality was not a limiting factor for radiologic diagnostic performance in midfacial trauma. 相似文献
8.
Kristina Jackson Behan 《Clinical laboratory science》2005,18(4):221-225
OBJECTIVE: Screening for diabetes is recommended for individuals > or =45 years of age, or earlier if they manifest > or = one specific risk factors. This study examined the sensitivity and positive predictive value (PPV) of risk factor total for identifying individuals with diabetes and prediabetes. DESIGN: Subjects were interviewed to assess the presence of risk factors. Fasting plasma glucose levels were obtained. SETTING: The study occurred at a health fair in Greensburg, PA. PATIENTS: Six hundred sixty-one Caucasians between the ages of 19 and 100. RESULTS: Using the criterion of screening individuals with > or = one risk factors detected 100% of both diabetics and prediabetics. This dropped to 91.2% when screening individuals with > or = two factors. The PPV of the risk factor total was poor (80% of individuals with a total of four factors were not diabetic). The ability of the risk factor total to predict individuals with impaired glucose metabolism (prediabetics + diabetics) was considerably better, and increased almost linearly with the risk factor total. Of the subjects with normal glucose values, the mean glucose increased as the risk factor total increased. CONCLUSION: While the sensitivity of using > one risk factor as an algorithm to screen is 100% for identifying diabetics, the PPV of risk factor analysis for identifying diabetics is poor. The same algorithm works well to identify at-risk individuals, presumably allowing early intervention and education. 相似文献
9.
10.
Disc herniation in the lumbar spine during growth: Long-term results of operative treatment in 18 patients 总被引:1,自引:0,他引:1
M. Poussa D. Schlenzka S. Mäenpää J. Merikanto P. Kinnunen 《European spine journal》1997,6(6):390-392
We studied 18 patients who had undergone surgery for herniated lumbar discs between the ages of 11 and 17 years. The inclusion criteria for girls was an age of 15 years or below and for boys 17 or below at surgery. The mean follow-up time was 10 years and the clinical outcome was good. Age at surgery and length of the follow-up had no effect on the result. The radiological disc height at follow-up did not correlate with the follow-up time or age of the patient at operation. MRI scans at follow-up from ten patients operated at less than 15 years of age revealed multilevel disc degeneration but favourable clinical results. 相似文献