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991.

Background  

Since the 1991 Gulf War concerns have been raised about the effects of deployment to the Gulf War on veterans' health. Studies of the reproductive health of Gulf War veterans have reported varied findings.  相似文献   
992.
PURPOSE: A method and computer tool to estimate percentage magnetic resonance (MR) imaging (MRI) breast density using three-dimensional T(1)-weighted MRI is introduced, and compared with mammographic percentage density [X-ray mammography (XRM)]. MATERIALS AND METHODS: Ethical approval and informed consent were obtained. A method to assess MRI breast density as percentage volume occupied by water-containing tissue on three-dimensional T(1)-weighted MR images is described and applied in a pilot study to 138 subjects who were imaged by both MRI and XRM during the Magnetic Resonance Imaging in Breast Screening study. For comparison, percentage mammographic density was measured from matching XRMs as a ratio of dense to total projection areas scored visually using a 21-point score and measured by applying a two-dimensional interactive program (CUMULUS). The MRI and XRM percent methods were compared, including assessment of left-right and interreader consistency. RESULTS: Percent MRI density correlated strongly (r = 0.78; P < 0.0001) with percent mammographic density estimated using Cumulus. Comparison with visual assessment also showed a strong correlation. The mammographic methods overestimate density compared with MRI volumetric assessment by a factor approaching 2. DISCUSSION: MRI provides direct three-dimensional measurement of the proportion of water-based tissue in the breast. It correlates well with visual and computerized percent mammographic density measurements. This method may have direct application in women having breast cancer screening by breast MRI and may aid in determination of risk.  相似文献   
993.
PURPOSE: Saccharomyces cerevisiae, a nonpathogenic yeast, has been used previously as a vehicle to elicit immune responses to foreign antigens, and tumor-associated antigens, and has been shown to reduce tumor burden in mice. Studies were designed to determine if vaccination of human carcinoembryonic antigen (CEA)-transgenic (CEA-Tg) mice (where CEA is a self-antigen) with a recombinant S. cerevisiae construct expressing human CEA (yeast-CEA) elicits CEA-specific T-cell responses and antitumor activity. EXPERIMENTAL DESIGN: CEA-Tg mice were vaccinated with yeast-CEA, and CD4(+) and CD8(+) T-cell responses were assessed after one and multiple administrations or vaccinations at multiple sites per administration. Antitumor activity was determined by tumor growth and overall survival in both pulmonary metastasis and s.c. pancreatic tumor models. RESULTS: These studies demonstrate that recombinant yeast can break tolerance and that (a) yeast-CEA constructs elicit both CEA-specific CD4(+) and CD8(+) T-cell responses; (b) repeated yeast-CEA administration causes increased antigen-specific T-cell responses after each vaccination; (c) vaccination with yeast-CEA at multiple sites induces a greater T-cell response than the same dose given at a single site; and (d) tumor-bearing mice vaccinated with yeast-CEA show a reduction in tumor burden and increased overall survival compared to mock-treated or control yeast-vaccinated mice in both pulmonary metastasis and s.c. pancreatic tumor models. CONCLUSIONS: Vaccination with a heat-killed recombinant yeast expressing the tumor-associated antigen CEA induces CEA-specific immune responses, reduces tumor burden, and extends overall survival in CEA-Tg mice. These studies thus form the rationale for the incorporation of recombinant yeast-CEA and other recombinant yeast constructs in cancer immunotherapy protocols.  相似文献   
994.
Primary care nurses are very likely to provide a substantial part of the routine care for patients with dementia. In order to examine the knowledge and attitudes of the primary care nurses who undertake the Over-75 Check, towards assessing and managing patients with symptoms of dementia, and to assess their level of support for a clinical practice guideline, a postal questionnaire survey was undertaken of primary care nurses responsible for the Over-75 Check in 209 general practices in Gloucester, Avon and Somerset. The questionnaire ascertained some demographic information about the nurses, their training and the practice routine for the Over-75 Check. It also included a case vignette describing a typical presentation of dementia at an Over-75 Check. A 65% response rate was achieved. Only one-fifth of respondents ever used formal validated cognitive tests as part of the Over-75 Check. In response to the vignette, nearly 10% took no action at all and a further 25% simply referred the patient on. Amongst the remainder there was considerable variation regarding the tasks considered to be within their remit. The respondents strongly supported the introduction of guidelines. Given the variation in professional responsibilities between practices, it is proposed that a clinical practice guideline covering diagnosis, assessment and management of dementia should address the practice as a whole rather than be targeted to specific professionals. The guideline should prompt professionals carrying out an Over-75 Check to recognize symptoms of dementia and raise awareness of the range of tasks which need to be undertaken in confirming diagnosis, assessing needs and managing patients. Results from this study suggest that improved training and increased autonomy for primary care nurses would improve access to services for these patients and their carers.  相似文献   
995.
OBJECTIVE: Our purpose was to compare the efficacy and safety of low-dose versus high-dose oxytocin regimens in the augmentation of labor.STUDY DESIGN: Three hundred ten term pregnancies requiring augmentation of labor underwent randomization to receive either a low-dose or high-dose oxytocin augmentation regimen. Maternal demographics, labor-delivery data, and neonatal outcome were compared.RESULTS: The hgih-dose oxytocin group had a significant lower cesarean section rate, regarless of parity (10.4% vs 25.7%. p < 0.001), with no differences in maternal complications and neonatal outcomes. The time needed to correct the labor abnormality as also significantly decreased (1.24 ± 1.4 hours vs 3.12 ± 1.6 hours, p < 0.001) in the high-dose group.CONCLUSIONS: The use of a high-dose oxytocin regimen benefits both nulliparous and multiparous women requiring labor augmentation by significantly lowering both the time necessary to correct the labor normality and the need for cesarean section.  相似文献   
996.
997.
Heterosexually acquired CRF01_AE/B recombinant HIV type 1 found in Thailand   总被引:1,自引:0,他引:1  
CRF01_AE and subtype B are circulating in Thailand and the strains have become intermixed in some high-risk groups, establishing the possibility of intersubtype recombination. The first such recombinant, mostly B with gp120 from CRF01_AE, was recently identified. Here we report a heterosexually acquired recombinant of different structure, with most of the genome from CRF01_AE but almost the entire envelope from subtype B. Surveillance by V3 serotype and genotype in multiple regions, followed by full-genome sequencing, was used to identify this strain. Pending vaccine trials in Thailand require knowledge of the presence of such strains in the population, and these recombinants provide valuable reagents for the laboratory evaluation of cross-subtype immunity. Studies are underway to determine whether either recombinant is circulating widely.  相似文献   
998.
BACKGROUND: Osteochondroma of the spine is a rare condition. We report a case of a patient with a cervical osteochondroma presenting with a polyneuropathy and polyradiculitis simultaneously. CASE DESCRIPTION: In a liver-transplant patient with progressive neurological deficits a polyneuropathy and a polyradiculitis were diagnosed. Eventually the patient became quadraparetic and an osteochondroma compressing the cervical spinal cord was found. The patient's neurological symptoms markedly improved after gross total tumor resection and antibiotic therapy. CONCLUSIONS: Review of the literature reveals this case to be an unusual presentation of a cervical osteochondroma, its diagnosis being delayed because of concomitant neurological diseases.  相似文献   
999.
1000.
Despite the now widespread experience with the administration of chemotherapeutic agents in oncology, extravasation injuries still occur. Furthermore, the most appropriate management of such injuries is not known. The authors examined the current treatment options for extravasation injury and the incidence of this problem. All cases of extravasation referred to the plastic surgery service at one institution from 1994 through 1996 were examined. During a 6-year period there were 44 cases of extravasation injury identified in 42 patients. Comparison with a previous study conducted 15 years before at the same institution revealed a significant reduction in the incidence of extravasation injuries during that time (0.01% vs. 0.1%; = 0.00). The site of extravasation was peripheral in 32 cases and central in 12. Paclitaxel and doxorubicin were the two most common drugs involved. The local infusion of antidotes was not performed routinely. Only 26 of the 42 patients were referred to the plastic surgery service for care. Only 10 of those 26 patients required local ulcer excision and closure to achieve a healed wound. The mean time between injury and referral was 40 days. This time did not predict the subsequent need for a surgical procedure. Most patients, including the remaining 16 referred to the plastic surgery service, did not require surgical intervention. All were watched expectantly, and their injuries healed spontaneously. In conclusion, the incidence of extravasation is decreasing, most likely as a result of the diligence in the administration and identification of extravasation injuries as well as the result of the use of more central infusion sites. Most cases can be managed conservatively, with directed surgical treatment of the ulceration when appropriate.  相似文献   
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