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1.
Marike Gabrielson Mattias Hammarström Magnus Bäcklund Jenny Bergqvist Kristina Lång Ann H Rosendahl Signe Borgquist Roxanna Hellgren Kamila Czene Per Hall 《International journal of cancer. Journal international du cancer》2023,152(11):2362-2372
Tamoxifen prevents recurrence of breast cancer and is suggested for preventive risk-reducing therapy. Tamoxifen reduces mammographic density, a proxy for therapy response, but little is known about its effects in remodelling normal breast tissue. Our study, a substudy within the double-blinded dose-determination trial KARISMA, investigated tamoxifen-specific changes in breast tissue composition and histological markers in healthy women. We included 83 healthy women randomised to 6 months daily intake of 20, 10, 5, 2.5, 1 mg of tamoxifen or placebo. The groups were combined to “no dose” (0-1 mg), “low-dose” (2.5-5 mg) or “high-dose” (10-20 mg) of tamoxifen. Ultrasound-guided biopsies were collected before and after tamoxifen exposure. In each biopsy, epithelial, stromal and adipose tissues was quantified, and expression of epithelial and stromal Ki67, oestrogen receptor (ER) and progesterone receptor (PR) analysed. Mammographic density using STRATUS was measured at baseline and end-of-tamoxifen-exposure. We found that different doses of tamoxifen reduced mammographic density and glandular-epithelial area in premenopausal women and associated with reduced epithelium and increased adipose tissue. High-dose tamoxifen also decreased epithelial ER and PR expressions in premenopausal women. Premenopausal women with the greatest reduction in proliferation also had the greatest epithelial reduction. In postmenopausal women, high-dose tamoxifen decreased the epithelial area with no measurable density decrease. Tamoxifen at both low and high doses influences breast tissue composition and expression of histological markers in the normal breast. Our findings connect epithelial proliferation with tissue remodelling in premenopausal women and provide novel insights to understanding biological mechanisms of primary prevention with tamoxifen. 相似文献
2.
Christian Holm Hansen Shelley Lees Saidi Kapiga Janet Seeley Tony Barnett 《Global public health》2020,15(3):402-413
ABSTRACTMeasuring hope reliably and accurately remains an important research objective, not least in less prosperous settings where ‘holding on to hope’ may be critically important in the struggle against adverse life conditions. The State Hope Scale was designed for use in the US. Despite reported application in diverse cultures and using translations the scale has not been extensively validated outside US populations. This study contributes to a larger project exploring the measurement of hope and provides a critique of Snyder’s scale as used in a Tanzanian female population of 1021 urban microfinance participants. We evaluate the scale’s validity through assessment of the empirical distribution of scores, item response profiles, internal consistency and discriminatory ability. Participants mostly scored very high and many reached very near the maximum attainable score. Hardly any endorsed the negative half of the response scale. Several problems are discussed including poor discrimination and strong evidence of acquiescence response bias. We also found little association of the scale scores with hypothesised correlates of hope. Future improvements on the measurement of hope are recommended, especially in studies outside the narrow Western context in which the scale was devised. 相似文献
3.
4.
Kristina W. Whitworth Brenda Berumen-Flucker George L. Delclos Sonia Fragoso Claudia Mata David Gimeno Ruiz de Porras 《Archives of environmental & occupational health》2020,75(2):70-74
AbstractThe occupational hazards and respiratory symptoms of domestic cleaners in USA are largely unknown. We conducted a cross-sectional study among 56 Hispanic female domestic cleaner on their health status and frequency of cleaning products used and tasks performed. While women used multi-use products (60.0%) and toilet bowl cleaners (51.8%) most days of the week, many (39.3%) reported not using personal protective equipment while cleaning. Itchy/watery eyes (61.8%) and itchy nose (56.4%) were the most frequently reported symptoms. A history of physician-diagnosed asthma was reported by 14.3% while 33.9% had symptoms of bronchial hyperresponsiveness (BHR). In conclusion, this vulnerable population has high prevalence of physician-diagnosis asthma and BHR symptoms and is potentially exposed to myriad occupational hazards. Further research exploring associations between products use, cleaning tasks and respiratory symptoms is warranted. 相似文献
5.
P Rubin S Holm L Friberg P Videbech H S Andersen B B Bendsen N Str?ms? J K Larsen N A Lassen R Hemmingsen 《Archives of general psychiatry》1991,48(11):987-995
To measure prefrontal and subcortical activity during a cognitive task, we examined 19 newly diagnosed schizophrenics and patients with schizophreniform psychosis. Seven healthy volunteers served as controls. The patients were drug naive or had received neuroleptics for a few days only. Cerebral blood flow distribution was depicted by single photon emission computed tomography at rest and during activation with the Wisconsin Card Sorting Test. A significant relative activation deficit in the left inferior-prefrontal region was revealed during the Wisconsin Card Sorting Test in the patient group. Furthermore, the patients had impaired striatal suppression on the left side during the cognitive task. The test performance was significantly impaired in the patients. The inability to reduce striatal activity may be due to a lack of corticostriatal feedback during prefrontal activation. 相似文献
6.
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
7.
BACKGROUND: Tinnitus is an uncomfortable symptom for the patient and an embarrassing one for the consulted physician. So far, there is no treatment that can be considered well established in terms of providing long-term reduction of tinnitus in excess of placebo effects. There is considerable evidence of pathophysiological similarity between tinnitus and chronic pain. Some forms of chronic pain can be treated by neurostimulation. OBJECTIVE: This study was designed to investigate the feasibility of neurostimulation of the cochlear nerve in order to reduce tinnitus. STUDY DESIGN: Pilot study. SETTING: Tertiary referral center. PATIENTS: Five patients with therapeutically refractory tinnitus were selected for this study. INTERVENTION: Placing a stimulation lead around the cochlear nerve through the suboccipital approach and connecting the stimulation lead to a pulse generator. MAIN OUTCOME MEASURES: The patients experienced 1) an absence of major or minor complications, such as death, meningitis, cranial nerve deficit, and vestibular problems; 2) tolerance of the procedure as considered by the patient; 3) relief of tinnitus in at least one patient. RESULTS: Implantation of the neurostimulation system was accomplished in each patient without any difficulty. None of the patients considered the treatment unbearable. No major or minor complications occurred in this study. Subjective tinnitus reduction was accomplished in four patients. CONCLUSION: Our preliminary data show that neurostimulation of the cochlear nerve is feasible, is bearable for the patient, and is a safe treatment modality without major complications. The effects on tinnitus are promising. 相似文献
8.
Direct (intraarterial) and two indirect (using a mercury sphygmomanometer [MS] and an automatic [auscultatory] device) methods of blood pressure measurement were compared in intensive care patients (N = 32). One trained observer blind to both automatic and direct measurements obtained all indirect MS measurements. All direct and indirect measurements were made on the same arm. Direct measurements were obtained from 10-second strip chart recordings. In normotensive patients both indirect measurements of systolic blood pressure (SBP) underestimated the direct SBP; however, only the SBP value obtained with the automatic device (106 mm Hg) was significantly different, p less than .05, from the direct SBP value (120 mm Hg). No significant difference was noted between methods in measurement of normotensive diastolic blood pressure. In hypertensive patients direct SBP was significantly greater, p less than .05, from both values obtained by indirect measurement. In patients without hypotension the automatic device may be substituted for the MS and direct blood pressure methods. The automatic device may offer the advantage of decreasing observer bias and variability in blood pressure measurement. 相似文献
9.
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
10.
Evaluation of beta-lactamase activity and microbial interference in treatment failures of acute streptococcal tonsillitis 总被引:2,自引:0,他引:2
Out of 169 patients with streptococcal tonsillitis treated with phenoxymethylpenicillin, 13 (8%) developed a new clinical infection with the same streptococcal strain within 2 weeks of completing the therapy (clinical treatment failure) and 24 (14%) were clinically healthy but harboured the same streptococcal strain after treatment (bacterial treatment failure). Patients with clinical treatment failure showed beta-lactamase activity in their saliva pellet significantly more often than patients with bacterial treatment failure, healed streptococcal tonsillitis or non-streptococcal tonsillitis as well as healthy controls. In an interference study, clinical treatment failures were compared with healthy streptococcal carriers, i.e. persons living in the same household and harbouring the same beta-streptococcal strain. 11/12 healthy carriers had alpha-streptococci with interfering activity against their own beta-streptococcal strain, while the corresponding figure for the clinical treatment failures was 2/13. Furthermore, 6/12 healthy carriers had beta-streptococci inhibiting their own alpha-strains, while the streptococci in 11/13 clinical treatment failures had this ability. The beta-lactamase activity and the interference between alpha- and beta-streptococci may be a contributory cause to treatment failure in streptococcal tonsillitis. 相似文献