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41.
Moshirfar A Showers D Logan P Esterhai JL 《Clinical orthopaedics and related research》1999,(360):110-121
Below the knee amputation after trauma is an appropriate option for many patients with recalcitrant infection and nonunion of the tibia. Patients who have had transtibial amputations have lower energy expenditure, heart rate, and oxygen cost when ambulating with their prostheses than when using a three-point gait with crutches without their artificial limb. Innovative prosthetists have improved each of the five essential components of the limb amputated below the knee: socket, insert, shaft and pylon, foot and ankle assembly, and suspension system. Prosthetists are integral members of the patient's healthcare team. Their recommendations and direct patient care are essential to optimizing the functional ability of patients who have had amputations. 相似文献
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M K Sammi C A Felder J S Fowler J H Lee A V Levy X Li J Logan I Pályka W D Rooney N D Volkow G J Wang C S Springer 《Magnetic resonance in medicine》1999,42(2):345-360
Two different types of (co-registered) images of the same slice of tissue will generally have different spatial resolutions. The judicious pixel-by-pixel combination of their data can be accomplished to yield a single image exhibiting properties of both. Here, axial (18)FDG PET and (1)H(2)O MR images of the human brain are used as the low- and high-resolution members of the pair. A color scale is necessary in order to provide for separate intensity parameters from the two image types. However, not all color scales can accommodate this separability. The HSV color model allows one to choose a color scale in which the intensity of the low-resolution image type is coded as hue, while that of the high-resolution type is coded as value, a reasonably independent parameter. Furthermore, the high-resolution image must have high contrast and be quantitative in the same sense as the low-resolution image almost always is. Here, relaxographic MR images (naturally segmented quantitative (1)H(2)O spin-density components) are used. Their essentially complete contrast serves to effect an apparent editing function when encoded as the value of the color scale. Thus, the combination of (18)FDG PET images with gray-matter (GM) relaxographic (1)H(2)O images produces visually "GM-edited" (18)FDG PETAMR (positron emission tomography and magnetic resonance) images. These exhibit the high sensitivity to tracer amounts characteristic of PET along with the high spatial resolution of (1)H(2)O MRI. At the same time, however, they retain the complete quantitative measures of each of their basis images. Magn Reson Med 42:345-360, 1999. Published 1999 Wiley-Liss, Inc. 相似文献
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目的: 研究1,25-二羟维生素D3 对结肠癌细胞系Caco-2 细胞中报告基因表达的作用,并探讨在报告载体pGL2 序列中存在潜在的抑制性维生素D应答元件(VDRE)的可能性。方法: 采用磷酸钙沉淀法将报告载体转染入Caco-2 细胞。Caco-2细胞经不同浓度1,25-二羟维生素D3 处理后测定细胞裂解液中表达的荧光素酶活性。结果: 应用pGL2 报告载体时,当用pSG5-VDR表达载体共转染后,1,25-二羟维生素D3显著地抑制Caco-2 细胞荧光素酶的表达(P< 0.05);而未使用该表达载体共转染则无抑制作用(P> 0.05)。应用pGL3 报告载体时,不同浓度的1,25-二羟维生素D3 对pLG3转染后Caco-2 细胞表达的荧光素酶活性均无显著抑制作用(P> 0.05),该作用不依赖是否存在有pSG5-VDR表达载体共转染。结论:1,25-二羟维生素D3 对报告载体PGL2 荧光素酶表达具有抑制作用,而对pGL3 则否;类似人类PTH基因中的潜在抑制性VDRE存在于报告载体pGL2,在pGL3 中该VDRE业已改变。 相似文献
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BACKGROUND: The role of immunosuppressive therapy in ulcerative colitis remains controversial. There is little information available on how frequently immunosuppressives are used, the circumstances, dose and duration of use and perceived benefit. METHODS: A postal survey was sent to consultant gastroenterologist members of the British Society of Gastroenterology. RESULTS: Questionnaires were returned by 81% of the 496 UK consultants approached. Azathioprine use was frequent, with 93% reporting previous use and 86% use within the past year. Although 95% usually prescribed a < or =2 mg/kg dose, only 39% were prepared to prescribe higher doses. There was marked variation in duration of use, with 46% using azathioprine for <2 years and 17% continuing it for 4 years or longer. Consultants with more experience of azathioprine in ulcerative colitis used it at higher maintenance doses for longer periods, and in patients with less extensive disease. Cyclosporin use was reported by 47% of those caring for ulcerative colitis patients, with 36% having used it at least once in the past year. However, 65% of users estimated that fewer than 50% of patients subsequently avoided colectomy. On stopping cyclosporin only 21% always introduced an alternative immunosuppressive, while 23% never did so. Potentially serious side-effects attributable to azathioprine and cyclosporin were reported by 36% and 45% of users of each drug, respectively. CONCLUSIONS: This survey reveals considerable variation in the amount and pattern of immunosuppressive use in ulcerative colitis, with serious side-effects commonly seen. There is a pressing need for further randomized controlled trials to provide reliable evidence as to how immunosuppressive therapy should be used in ulcerative colitis. 相似文献
48.
Luck JV Logan LR Benson DR Glasser DB 《The Journal of the American Academy of Orthopaedic Surgeons》1996,4(6):297-304
Orthopaedic surgeons practicing in areas with a high prevalence of human immunodeficiency virus (HIV) infection may expect that up to 7% of their patients who undergo emergent procedures and 1% to 3% of those who undergo elective surgery will be HIV-positive. Although basic science studies have demonstrated impairment of defenses to routine orthopaedic pathogens as well as to opportunistic organisms, clinical studies have shown that this impairment has not resulted in an increased incidence of postoperative infections or failure of wound healing in the asymptomatic HIV-positive patient. Even for the symptomatic patient, current medical management appears adequate to reduce the risk of early postoperative infection. The HIV-positive patient with a pros-thetic implant may be at increased risk for late hematogenous implant infection as host defenses diminish. Regular medical attention, prophylactic antibiotic therapy before dental work and invasive procedures, and early evaluation and treatment of possible infections are especially important in this setting. Decisions regarding elective surgery should be made on a risk-benefit basis. Because the risk of surgical complications increases with progression of the dis-ease, guidelines for elective surgery should include an assessment of the HIV-positive patient's immune status, including the CD4 lymphocyte count, history of opportunistic infection, serum albumin level, the presence of skin anergy, and the state of nutrition and general health. 相似文献
49.
Houtchens BA Clemmer TP Holloway HC Kiselev AA Logan JS Merrell RC Nicogossian AE Nikogossian HA Rayman RB Sarkisian AE 《Prehospital and disaster medicine》1993,8(1):57-66
The Telemedicine Spacebridge, a satellite-mediated, audio-video-fax link between four United States and two Armenian and Russian medical centers, permitted remote American consultants to assist Armenian and Russian physicians in the management of medical problems following the December 1988 earthquake in Armenia and the June 1989 gas explosion near Ufa. Methods: During 12 weeks of operations, 247 Armenian and Russian and 175 American medical professionals participated in 34 half-day clinical conferences. A total of 209 patients were discussed, requiring expertise in 20 specialty areas. Results: Telemedicine consultations resulted in altered diagnoses for 54, new diagnostic studies for 70, altered diagnostic processes for 47, and modified treatment plans for 47 of 185 Armenian patients presented. Simultaneous participation of several US medical centers was judged beneficial; quality of data transmission was judged excellent. Conclusion: These results suggest that interactive consultation by remote specialists can provide valuable assistance to on-site physicians and favorably influence clinical decisions in the aftermath of major disasters. 相似文献
50.
Because of the limited number of case reports on the use of electroconvulsive therapy (ECT) in adolescent psychiatric patients, we retrospectively reviewed the medical records of 20 young patients who underwent ECT. They constituted all the patients =18 years of age who had received ECT at our institution from 1983 through 1991. We also reviewed the literature. In our series of adolescents, ECT reduced or eliminated symptoms in patients with bipolar disorder, major depression, and schizophreniform disorder. It was less effective in patients with schizophrenia and schizoaffective disorder and produced no response in those with personality disorders. Treatments elicited no recorded adverse effects, even in patients with concomitant systemic problems, including a seizure disorder, a renal transplant, and a septum pellucidum cyst. We found ECT to be safe and effective in adolescents with severe and medication-resistant mental illnesses. 相似文献