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排序方式: 共有198条查询结果,搜索用时 15 毫秒
91.
Objective: The Adelaide Dental Study of Nursing Homes aimed to quantify oral disease experience, incidence and increments in Adelaide nursing home residents. Methods: Questionnaires and dental inspections were completed at baseline and at 1‐year for residents from randomly selected Adelaide nursing homes. Results: The residents were very functionally dependent, cognitively impaired and behaviourally difficult older adults with complex oral problems and dental treatment needs. The prevalence of edentulism (total tooth loss) (63%) decreased and more residents were retaining natural teeth. Existing residents had a mean of 10.8 teeth present and new residents had a mean of 12.7 teeth present. Residents’ previous experiences of caries (decay) were high – existing residents had a mean of 1.2 decayed teeth and new residents had a mean of 0.8 decayed teeth. Residents’ caries increments (new decay) over the 1‐year period were high (coronal = 2.5 surfaces; root = 1.0 surfaces), especially in those who had lost weight and who could eat fewer food types. These levels of caries were many times greater than had been reported for community‐dwelling older adults. Large accumulations of plaque, calculus and debris (food) were evident on residents’ natural teeth and dentures, especially those with dementia. Up to 25% of residents owned dentures that were not worn. Residents with dementia gave their carers complex and challenging oral hygiene care problems. Existing and new residents had similar general health and oral health characteristics, with the exceptions that new residents had significantly more filled tooth surfaces, and fewer decayed retained roots. Conclusion: New residents were being admitted to the nursing homes with a compromised oral health status or developed severe oral diseases and conditions within several months of their admittance. Residents’ oral diseases, especially coronal and root caries, rapidly progressed during their stay in residential care. 相似文献
92.
Unequal crossing-over: a common basis of single alpha-globin genes in Asians and American blacks with hemoglobin-H disease 总被引:5,自引:0,他引:5
Phillips JA d; Vik TA; Scott AF; Young KE; Kazazian HH Jr; Smith KD; Fairbanks VF; Koenig HM 《Blood》1980,55(6):1066-1069
The alpha-globin genes of five black Americans, two Chinese, and five Filipinos with HbH disease (an alpha-thalassemia state in which there is a single functional alpha gene) were analyzed by restriction endonuclease techniques. All subjects were found to have one chromosome 16, lacking both alpha genes, and another containing a single alpha gene (--/-alpha). Restriction endonuclease patterns of the DNA obtained from all 12 subjects were identical and compatible with unequal crossing-over as the mechanism of origin of the single alpha gene in these individuals. 相似文献
93.
KD May-Newman BK Hillen CS Sironda W Dembitsky 《Journal of medical engineering & technology》2013,37(3):105-109
Background and aim: The goal of this study was to evaluate the effect of surgical anastomosis configuration of the aortic outflow conduit (AOC) from a continuous flow left ventricular assist device (LVAD) on the flow fields in the aorta using CFD simulations. The geometry of the surgical integration of the LVAD is an important factor in the flow pattern that develops both in series (aortic valve closed, all flow through LVAD) and in parallel (heart pumping in addition to LVAD).Methods: CFD models of the AOC junctions simulate geometry as cylindrical tubes that intersect at angles ranging from 30° to 90°. Velocity fields are computed over a range of cardiac output for both series and parallel flow.Results: Our results demonstrate that the flow patterns are significantly affected by the angle of insertion of the AOC into the native aorta, both during series and parallel flow conditions. Zones of flow recirculation and high shear stress on the aortic wall can be observed at the highest angle, gradually decreasing in size until disappearing at the lowest angle of 30°. The highest velocity and shear stress values were associated with series flow.Conclusions: The results suggest that connecting the LVAD outflow conduit to the proximal aorta at a shallower angle produces fewer secondary flow patterns in the native cardiovascular system. 相似文献
94.
BN Doebbeling TE Vaughn KD McCoy SE Beekmann RF Woolson KJ Ferguson JC Torner 《Clinical infectious diseases》2003,37(8):1006-1013
To examine factors associated with blood exposure and percutaneous injury among health care workers, we assessed occupational risk factors, compliance with standard precautions, frequency of exposure, and reporting in a stratified random sample of 5123 physicians, nurses, and medical technologists working in Iowa community hospitals. Of these, 3223 (63%) participated. Mean rates of hand washing (32%-54%), avoiding needle recapping (29%-70%), and underreporting sharps injuries (22%-62%; overall, 32%) varied by occupation (P<.01). Logistic regression was used to estimate the adjusted odds of percutaneous injury (aOR(injury)), which increased 2%-3% for each sharp handled in a typical week. The overall aOR(injury) for never recapping needles was 0.74 (95% CI, 0.60-0.91). Any recent blood contact, a measure of consistent use of barrier precautions, had an overall aOR(injury) of 1.57 (95% CI, 1.32-1.86); among physicians, the aOR(injury) was 2.18 (95% CI, 1.34-3.54). Adherence to standard precautions was found to be suboptimal. Underreporting was found to be common. Percutaneous injury and mucocutaneous blood exposure are related to frequency of sharps handling and inversely related to routine standard-precaution compliance. New strategies for preventing exposures, training, and monitoring adherence are needed. 相似文献
95.
Meniscal ossicle: radiographic and MR imaging findings 总被引:2,自引:0,他引:2
96.
97.
Effects of interleukin-3 and granulocyte-macrophage colony-stimulating factor on thrombopoiesis in congenital amegakaryocytic thrombocytopenia 总被引:1,自引:1,他引:0
Guinan EC; Lee YS; Lopez KD; Kohler S; Oette DH; Bruno E; Kozakewich H; Nathan DG; Hoffman R 《Blood》1993,81(7):1691-1698
Amegakaryocytic thrombocytopenia (AMT) is a rare and often fatal disorder of infancy and childhood presenting with isolated thrombocytopenia that progresses to marrow failure. The defect in thrombopoiesis is not well understood nor is the etiology of the progressive marrow failure. No standard modality of treatment exists. Here, we evaluated the capacity of marrow cells isolated from five patients with AMT and progressive marrow failure to generate megakaryocyte progenitor cells (CFU-MK). These in vitro studies demonstrated assayable numbers of CFU-MK from all patient bone marrows that responded in vitro to the addition of interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), or the combination of both. These findings suggest that the defect in AMT might be partially correctable by the administration of these cytokines. A Phase I/II trial of in vivo administration of these same hematopoietins in the identical patients was conducted in which no significant toxicity was observed. IL-3 but not GM-CSF administration resulted in improved platelet counts in two patients and decreased bleeding and transfusion requirement in the remaining three. No clinical benefit was observed when GM-CSF was administered after IL-3 pretreatment. Prolonged IL-3 administration has resulted in platelet increases in an additional two patients. In vitro responsiveness of CFU- MK to either cytokine did not predict the degree of clinical response. Although the optimal dose and schedule of IL-3 either alone or in combination remains to be established, this study suggests that IL-3 may contribute to the treatment of patients with AMT. 相似文献
98.
99.
KD Crissinger 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S396):8-10
The pathogenesis of necrotizing enterocolitis remains unknown, but various factors have been postulated including, but not limited to, mesenteric ischemia, enteral alimentation, and infection. Since an understanding of circulatory physiology in developing intestine may provide insight into the role of mesenteric ischemia in the etiology of necrotizing enterocolitis, this review summarizes what is currently known about the regulation of blood flow and oxygenation in developing intestine and how it differs from that in adult intestine. The discussion is divided into intrinsic versus extrinsic factors. Phenomena which may be used to evaluate the capacity for intrinsic vasoregulation include pressure-flow autoregulation, reactive hyperemia, venous hypertension, arterial hypoxemia, and postprandial hyperemia. Extrinsic factors include neurologic and hormonal influences. Additionally, the susceptibility for tissue hypoxia as a function of age and the correlation with subsequent development of mucosal injury are discussed 相似文献
100.