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排序方式: 共有487条查询结果,搜索用时 15 毫秒
1.
The effect of currently available contact lens disinfection systems on Acanthamoeba castellanii and Acanthamoeba polyphaga 总被引:6,自引:0,他引:6
R E Silvany J M Dougherty J P McCulley T S Wood R W Bowman M B Moore 《Ophthalmology》1990,97(3):286-290
Contact lens disinfection systems were evaluated for their effectiveness in killing Acanthamoeba castellanii and Acanthamoeba polyphaga trophozoites and cysts. Amoebae were inoculated into commercially available contact lens cleaning and soaking solutions. At intervals varying from 30 minutes to 24 hours, solutions were filtered. The filters were removed and cultured for Acanthamoeba organisms. Striking differences were observed in the abilities of the different disinfecting solutions to kill the organisms. Solutions containing chlorhexidine were effective at very short exposure times. Solutions containing benzalkonium chloride required slightly longer exposure times but were faster than solutions containing only thimerosal. Solutions containing sorbate, polyaminopropyl biguanide, or polyquaternium-1 were not effective at killing Acanthamoeba organisms in the time allotted for the experiment. Solutions containing hydrogen peroxide were quite effective if the agent was not prematurely catalyzed. A. polyphaga generally required longer exposure to disinfectants than did A. castellanii for complete inhibition to occur. 相似文献
2.
Comparison of outcomes and donor-site morbidity in unilateral free TRAM versus DIEP flap breast reconstruction. 总被引:2,自引:0,他引:2
M V Schaverien A G B Perks S J McCulley 《Journal of plastic, reconstructive & aesthetic surgery》2007,60(11):1219-1224
BACKGROUND: At long-term follow up we cannot easily differentiate between patients who have undergone free transverse rectus abdominis musculocutaneous (TRAM) flap and deep inferior epigastric artery perforator (DIEP) flap breast reconstruction in terms of subjective functional limitations of daily activities. The aim of this study was to evaluate postoperative outcomes and long-term subjective functional deficit in patients following unilateral free TRAM compared with DIEP flap breast reconstruction. METHODS: Sixty consecutive patients who underwent unilateral autologous breast reconstruction were included in the study, 30 of whom had undergone a DIEP flap, and 30 a free TRAM flap. Surgical and postoperative outcome data were collected and a postal questionnaire was sent to each patient at least 6 months postoperatively consisting of a short functional assessment questionnaire and a Short Form 36 (SF-36) survey. RESULTS: We found no significant difference in postoperative outcomes or in the subjective ability to perform activities of daily living, including work, domestic activities, sports and hobbies, between patients who underwent TRAM flap breast reconstruction and those who underwent a DIEP flap, and no significant difference between the groups for scores on the physical functioning, role-physical, or bodily pain scales of the SF-36. CONCLUSION: We conclude that harvesting of the free TRAM flap results in no significant difference in postoperative outcomes or in the subjective ability to perform activities of daily living compared with the DIEP flap. 相似文献
3.
Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
4.
Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm). 相似文献
5.
Dongari-Bagtzoglou AI; Warren WD; Berton MT; Ebersole JL 《International immunology》1997,9(9):1233-1241
CD40, a member of the tumor necrosis factor-alpha receptor family, is
constitutively expressed by cells of hematopoietic and non- hematopoietic
origin, including fibroblasts. Signaling through this receptor molecule
regulates inflammatory cytokine secretion by many cell types. Based on the
recently described cytokine secretory heterogeneity of fibroblast cell
subsets, we hypothesized that secretion of inflammatory cytokines by
gingival fibroblast cultures may be dictated by the existence of
differential proportions of cytokine- secreting subpopulations which
express high levels of CD40. After examining a large number of gingival
fibroblast (GF) cultures we find that the frequency of IL-6- and
IL-8-secreting cells mirrors the frequency of cells expressing high levels
of CD40 in these cultures. In addition, we demonstrate a direct functional
relationship between CD40 expression and IL-6 or IL-8 secretion by showing
that ligation of this molecule on GF, and CD40+ fibroblast subsets in
particular, up- regulates secretion of these cytokines in vitro.
相似文献
6.
7.
David J McCulley Ji-One Kang James F Martin Brian L Black 《Developmental dynamics》2008,237(11):3200-3209
The endocardial cushions play a critical role in septation of the four-chambered mammalian heart and in the formation of the valve leaflets that control blood flow through the heart. Within the outflow tract (OFT), both cardiac neural crest and endocardial-derived mesenchymal cells contribute to the endocardial cushions. Bone morphogenetic protein 4 (BMP4) is required for endocardial cushion development and for normal septation of the OFT. In the present study, we show that anterior heart field (AHF)-derived myocardium is an essential source of BMP4 required for normal endocardial cushion expansion and remodeling. Loss of BMP4 from the AHF in mice results in an insufficient number of cells in the developing OFT endocardial cushions, defective cushion remodeling, ventricular septal defects, persistent truncus arteriosus, and abnormal semilunar valve formation. 相似文献
8.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
9.
FJ Cowan JT Warner FD Dunstan WD Evans JW Gregory HR Jenkins 《Archives of disease in childhood》1997,76(4):325-329
The prevalence of osteopenia in children with inflammatory bowel disease (IBD) is unknown. The effect of nutritional state, disease activity, and steroid therapy on bone mineral content (BMC) of whole body, lumbar spine, and left femoral neck measured by dual energy x ray absorptiometry in 32 children with IBD was assessed by comparison with 58 healthy local school children. Using the control data, a predicted BMC was calculated taking into account bone area, age, height, weight, and pubertal stage. The measured BMC in children with IBD was expressed as a percentage of this predicted value (% BMC). Mean (SD) % BMC was significantly reduced for the whole body and left femoral neck in the children with IBD (97.0 (4.5)% and 93.1 (12.0)% respectively, p < 0.05). Of the children with IBD, 41% had a % BMC less than 1 SD below the mean for the whole body and 47% at the femoral neck. Reduction in % BMC was associated with steroid usage but not with the magnitude of steroid dose, disease activity, or biochemical markers of bone metabolism. In conclusion, osteopenia is relatively common in childhood IBD and may be partly related to the previous use of steroids. 相似文献
10.
K S Asgeirsson T Rasheed S J McCulley R D Macmillan 《European journal of surgical oncology》2005,31(8):817-823
BACKGROUND: Breast-conserving surgery and radiotherapy is firmly established as a good and safe option for most women with early breast cancer. The important outcome measures of breast conservation are survival, local recurrence, cosmesis and patient satisfaction. Partial breast reconstructive techniques may improve cosmesis and patient satisfaction without compromising the oncological outcomes. METHODS: A search of the Medline and Pubmed databases of studies on breast conserving surgery where partial breast reconstructive techniques were employed. The keywords used were breast conserving surgery, oncoplastic breast surgery, partial breast reconstruction and reduction mammoplasty. The oncological and cosmetic outcomes of these studies were analysed. RESULTS: Studies on partial breast reconstructive techniques often lack oncological outcomes and long-term results are not available. On intermediate follow-up (up to 4.5 years) local recurrence rates vary from 0 to 1.8% per year. Cosmetic failure rates vary from 0 to 18%. To date, detailed studies are small and outcome measures vary. CONCLUSIONS: Breast surgeons should be aware of the range of surgical techniques that may enhance the aesthetic results of breast-conserving surgery as well as expand the indications for its use. There is a need for routine assessment of oncological and cosmetic outcomes and long-term results of partial breast reconstructive techniques in relation to these outcomes are awaited. 相似文献