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The serotonin 1B (5-HT1B) receptor has lately received considerable interest in relation to psychiatric and neurological diseases, partly due to findings based on quantification using Positron Emission Tomography (PET). Although the brainstem is an important structure in this regard, PET radioligand binding quantification in brainstem areas often shows poor reliability. This study aims to improve PET quantification of 5-HT1B receptor binding in the brainstem.Volumes of interest (VOIs) were selected based on a 3D [3H]AZ10419369 Autoradiography brainstem model, which visualized 5-HT1B receptor distribution in high resolution. Two previously developed VOI delineation methods were tested and compared to a conventional manual method. For a method based on template data, a [11C]AZ10419369 PET template was created by averaging parametric binding potential (BPND) images of 52 healthy subjects. VOIs were generated based on a predefined volume and BPND thresholding and subsequently applied to test-retest [11C]AZ10419369 parametric BPND images of 8 healthy subjects. For a method based on individual subject data, VOIs were generated directly on each individual parametric image.Both methods showed improved reliability compared to a conventional manual VOI. The VOIs created with [11C]AZ10419369 template data can be automatically applied to future PET studies measuring 5-HT1B receptor binding in the brainstem.  相似文献   
83.
OBJECTIVE: The aim was to evaluate the outcome of fertility-sparing treatment in ovarian borderline tumors and early invasive ovarian cancer. MATERIALS AND METHODS: All women diagnosed with an ovarian borderline tumor or early invasive ovarian cancer who were treated with fertility-sparing surgery at the University Hospital in Lund between 1988 and 2002 were identified and included in the study (n=23). RESULTS: During the follow-up period of a median 92 months, range 11-185 months, no relapse was found in the patients with Stage 1a tumors, including both borderline tumors (n=12) and invasive well-differentiated (n=9) and moderately differentiated (n=1) ovarian cancers. One patient with poorly differentiated ovarian cancer Stage 1c was 13 weeks' pregnant at the time of the primary operation. Although, unilateral oophorectomy was performed she insisted on continuing the pregnancy. At 37 weeks she had a cesarean section and the ovarian cancer was disseminated. Chemotherapy was given but she died less than a year later. None of the other patients received chemotherapy. In total, 30 children were born to 15 patients. Prophylactic removal of the remaining ovary+/-hysterectomy was accepted in only in six of the women after fulfilling their desire to have more children. CONCLUSIONS: Young women with Stage 1a epithelial ovarian cancer and borderline tumors do not have to give up their fertility in order to receive successful and safe treatment of their disease. However, several of these patients do not accept the recommendation of prophylactic oophorectomy of the contralateral ovary and hysterectomy after completion of childbearing.  相似文献   
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This paper reviews the conceptualization of addiction on prescribed sedative-hypnotics medications; its evolution, occurrence, characteristics and validity. Such addictive behaviour is often concurrent with severe anxiety and/or personality disorders and follows a dismal course. The rate of suicide is very high, particularly in health care personnel with access to lethal medications. The risk of developing this kind of addiction is miniscule, considering the mass exposure to these medications in the general population. Yet, moralizing arguments amplified by the media, as well as overzealous government interventions create unnecessary obstacles to proper and effective pharmacotherapy for morbid anxiety and insomnia. © 1996 John Wiley & Sons, Ltd.  相似文献   
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Synaptic vesicle glycoprotein 2A (SV2A) has been previously characterized as an imaging biomarker for assessment of synaptic density in positron emission tomography (PET) studies of patients with neurological conditions. To provide detailed maps of the brain localization of SV2A autoradiography studies were carried out using the SV2A radioligand [11C]UCB-J and whole hemisphere sections of non-human primate (NHP) and human brain. Binding of [11C]UCB-J was observed in all evaluated grey matter structures of the primate brain, with highest density in the caudate nucleus and cortex and lowest density in pons and globus pallidus. The density of [11C]UCB-J binding sites in human brain showed a good correlation with that in NHP brain. Binding of [11C]UCB-J in the white matter was very low relative to that in grey matter containing structures and was only inhibited to a minor extent by co-incubation with a saturating concentration of unlabelled UCB-J. The high-resolution images obtained in the present study may aid the interpretation of data acquired in human subjects examined using [11C]UCB-J in PET studies. In addition, observation of low binding for [11C]UCB-J in white matter (centrum semiovale) supports that this structure can be used as a reference region for quantitative analysis of [11C]UCB-J PET data.  相似文献   
88.
Objectives: Synthetic and biological materials are increasingly used to provide temporary or permanent scaffolds for bone regeneration. This study evaluated the effect of material chemistry and microporosity on bone ingrowth and osseointegration of zirconia (ZrO2) and hydroxyapatite (HA) scaffolds in the human maxilla.
Material and methods: Twelve patients subjected to dental implant placement were enrolled in the study. Scaffolds of ZrO2 and HA were placed in the maxilla of each subject, using a randomization protocol. After 3 months of healing, biopsies were harvested comprising the scaffolds and surrounding bone tissue. The biopsies were processed for histological evaluation and morphometric analysis (bone ingrowth and bone-to-scaffold contact).
Results: Healing was uneventful in all cases. All scaffolds demonstrated a measurable bone response using light microscopy and scanning electron microscopy. Microporous HA scaffolds revealed four times larger bone ingrowth and seven times larger bone contact as compared with ZrO2 scaffolds.
Conclusion: The results show that chemistry and microporosity of HA promote bone ingrowth and bone contact of ceramic scaffolds in human maxilla.  相似文献   
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Scand J Caring Sci; 2011; 25; 325–332
Assistant nurses working in care of older people: associations with sustainable work ability Indicators of health have shown improvements in the Swedish working population during the past decades, but with the exception of low‐skilled women. Earlier research has shown that assistant nurses belong to an occupational group, which has the lowest share of individuals with long‐term health in the total Swedish workforce. Sick leave research has mostly focused on determining risk factors for the development of diseases and dysfunctions. In the process of acquiring knowledge about mechanisms for sick leave, it has become obvious that there is also a need to focus on what contributes to work ability. The aim in this study was to explore what promotes sustainable work ability in female assistant nurses working in care of older people. Associations between factors related to work, health, lifestyle and sustainable work ability were investigated in a cross‐sectional nested case–control study in a cohort of 366 female assistant nurses. Data were collected in self‐reports in a questionnaire. Odds ratios were calculated, and a multiple logistic regression analysis was performed with sustainable work ability as the dependent variable. Sustainable work ability was associated with good self‐rated health, a BMI <30, ability to sleep well, recuperation, low stress level, support from family and friends, being over 25 years of age at birth of the first child, and control over one’s own life in the ≥50 age group. In the logistic regression analysis, the significant associations were good self‐rated health, being over 25 years of age at the birth of the first child and recuperation. In conclusion, the study showed that self‐rated health and factors in private life are important for assistant nurse’s sustainable work ability over time. The results from this study could be applied in health promotion work for employees in the care sector to strengthen and enhance sustainable work ability.  相似文献   
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