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81.
Calculation of the absorbed dose by different lung cells is necessary for predicting the critical cells that are subject to injury from inhaled Rn and other alpha-particle sources. The absorbed dose was determined for cells in the airways of human and rat lungs, based on airway epithelial thickness and on cell cytoplasm and nuclear volume density as a function of depth from the luminal surface of the airway epithelium. The thickness of the stratified columnar epithelium of human airways varied from 57.8 micron in bronchi to 9.8 microns in bronchioles. The cell populations of all bronchi in human lungs were comparable. The cell populations of trachea and intrapulmonary airways in rats, however, were significantly different. Basal cell populations in rat trachea and human bronchi were similar and formed a nearly continuous layer. In rat bronchi, basal cells were not present in significant numbers. Measurements of epithelial thickness and volume density were used to estimate the absorbed dose for an alpha-particle source (214Po or 218Po) distributed uniformly in the mucus with an equivalent activity of 1 dpm per cm2 of epithelial surface. The following model predictions of dose to human bronchial epithelial cell nuclei for a 218Po alpha-particle source are provided in units of nanogray (nGy) for specific cell types: secretory 158, preciliated 114, ciliated 44, goblet 86, basal 78, and indeterminate cell nuclei 73. The absorbed dose to specific types of rat bronchial epithelial cell nuclei was also predicted: secretory 237, precillated 216, ciliated 203, goblet 204, basal 200, and indeterminate cell nuclei 166 nGy. These and other results indicate that human and rat airway dosimetry have significant differences that may contribute to the differences in cancer cell induction between the two species. 相似文献
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84.
BACKGROUND: Changing trends in cataract extractions have resulted in a new category of bullous keratopathy: corneal decompensation after complicated extracapsular cataract extraction. These cases of bullous keratopathy are associated with rupture of the posterior capsule, vitreous loss, and significant intraocular inflammation at the time of the original complicated extracapsular cataract extraction. METHODS: The authors reviewed 14 consecutive cases of penetrating keratoplasty for bullous keratopathy in which posterior chamber intraocular lens implantation was supported by remnants of the posterior capsule and/or Soemmering's ring without suture fixation. All 14 patients had a history of complicated extracapsular cataract extraction with capsule rupture and vitreous loss. RESULTS: All 14 patients had clear, compact grafts without migration of the intraocular lens with a mean follow-up of 12.1 months. Vision improved in 93% of cases, and there was no significant worsening of glaucoma. CONCLUSIONS: Pseudophakic bullous keratopathy after traumatic extracapsular cataract extraction with an anterior chamber intraocular lens and aphakic bullous keratopathy after traumatic extracapsular cataract extraction are two relatively new clinical entities that present new intraocular lens management options. Bullous keratopathy after complicated extracapsular cataract extraction should be recognized as a distinct clinical entity. Intraocular lens implantation into the ciliary sulcus with Soemmering's ring and peripheral capsular support provide the advantages of a posterior chamber intraocular lens without the risk of iris or scleral sutures. The authors predict that bullous keratopathy associated with traumatic extracapsular cataract extraction will become one of the more common indications for penetrating keratoplasty. 相似文献
85.
N K Russell B O Boekeloo I Z Rafi D L Rabin 《American journal of preventive medicine》1992,8(4):235-240
Studies describing sexually transmitted disease (STD) and human immunodeficiency virus (HIV) prevention practices of primary care physicians have relied on physician or patient reports. This study describes physician STD/HIV prevention practices as observed by unannounced simulated patient evaluators (SPEs). SPEs visited sixty-five primary care physicians. Each SPE portrayed a sexually active female, new to the area, requesting a consultation on STD prevention. One-third of the physicians in the study asked no risk questions, and over 80% failed to ask the SPE specifically about her sexual practices. Most physicians discussed the risks of STDs and HIV and covered basic recommendations (use condoms and know partners better); however, few physicians provided any individualized information or advice about safer sexual practices and the specifics of condom use, such as how to use them or what kind to use. These observations support the low rates of STD/HIV prevention indicated in physicians' self-report and further identify specific deficiencies in the thoroughness of their risk assessment and preventive counseling practices. 相似文献
86.
J. A. Kobashigawa L. W. Miller S. D. Russell G. A. Ewald M. J. Zucker L. R. Goldberg H. J. Eisen K. Salm D. Tolzman J. Gao W. Fitzsimmons R. First 《American journal of transplantation》2006,6(6):1377-1386
The most advantageous combination of immunosuppressive agents for cardiac transplant recipients has not yet been established. Between November 2001 and June 2003, 343 de novo cardiac transplant recipients were randomized to receive steroids and either tacrolimus (TAC) + sirolimus (SRL), TAC + mycophenolate mofetil (MMF) or cyclosporine (CYA) + MMF. Antilymphocyte induction therapy was allowed for up to 5 days. The primary endpoint of >/=3A rejection or hemodynamic compromise rejection requiring treatment showed no significant difference at 6 months (TAC/MMF 22.4%, TAC/SRL 24.3%, CYA/MMF 31.6%, p = 0.271) and 1 year (p = 0.056), but it was significantly lower in the TAC/MMF group when compared only to the CYA/MMF group at 1 year (23.4% vs. 36.8%; p = 0.029). Differences in the incidence of any treated rejection were significant (TAC/SRL = 35%, TAC/MMF = 42%, CYA/MMF = 59%; p < 0.001), as were median levels of serum creatinine (TAC/SRL = 1.5 mg/dL, TAC/MMF = 1.3 mg/dL, CYA/MMF = 1.5 mg/dL; p = 0.032) and triglycerides (TAC/SRL = 162 mg/dL, TAC/MMF = 126 mg/dL, CYA/MMF = 154 mg/dL; p = 0.028). The TAC/SRL group encountered fewer viral infections but more fungal infections and impaired wound healing. These secondary endpoints suggest that the TAC/MMF combination appears to offer more advantages than TAC/SRL or CYA/MMF in cardiac transplant patients, including fewer >/=3A rejections or hemodynamic compromise rejections and an improved side-effect profile. 相似文献
87.
The recent Confidential Enquiry (2000-2002) has emphasised 'emergency drills for maternal resuscitation should be regularly practised in clinical areas in all maternity units'. It was therefore planned to assess the knowledge of airway management and ventilation among obstetrics and gynaecology trainees in the Yorkshire Deanery (Training Region). Questionnaires were given to trainees attending the Modular Training Programme and were collected on the same day. A total of 71 questionnaires were collected which represents 62% of the 113 trainees in Yorkshire region. Replies were received from 39 registrars, 27 Senior House Officers (SHO), four Senior SHOs (SSHO) and one clinical fellow. MRCOG Part 1 was passed by 52% and 36% of trainees had MRCOG Part 2. A total of 69% of trainees did not know that chin lift opens the airway in some 70 - 80% of patients; 50% of trainees were not aware why jaw thrust is preferred over chin lift; 76% of the trainees knew the most common cause of airway obstruction in a patient with an altered level of consciousness--the tongue falls back and obstructs the pharynx ('swallowing the tongue'). Knowledge of the main cause of airway obstruction was good among obstetrics and gynaecology trainees, but their understanding of how to manage this was found to be relatively poor. Attendance at a local Basic Life Support course should be compulsory for obstetric and gynaecology trainees early in their career. 相似文献
88.
D Ruta A Coutts M Abdalla J Masson E Russell P Brunt A McKinlay A Mowat T Sinclair 《Quality in health care》1995,4(3):161-165
OBJECTIVE--To assess the feasibility of monitoring health outcomes in a routine hospital setting and the value of feedback of outcomes data to clinicians by using the SF 36 health survey questionnaire. DESIGN--Administration of the questionnaire at baseline and three months, with analysis and interpretation of health status data after adjustments for sociodemographic variables and in conjunction with clinical data. Exploration of usefulness of outcomes data to clinicians through feedback discussion sessions and by an evaluation questionnaire. SETTING--One gastroenterology outpatient department in Aberdeen Royal Hospitals Trust, Scotland. PATIENTS--All (573) patients attending the department during one month (April 1993). MAIN MEASURES--Ability to obtain patient based outcomes data and requisite clinical information and feed it back to the clinicians in a useful and accessible form. RESULTS--Questionnaires were completed by 542 (95%) patients at baseline and 450 (87%) patients at follow up. Baseline health status data and health outcomes data for the eight different aspects of health were analysed for individual patients, key groups of patients, and the total recruited patient population. Significant differences were shown between patients and the general population and between different groups of patients, and in health status over time. After adjustment for differences in sociodemography and main diagnosis patients with particularly poor scores were identified and discussed. Clinicians judged that this type of assessment could be useful for individual patients if the results were available at the time of consultation or for a well defined group of patients if used as part of a clinical trial. CONCLUSIONS--Monitoring routine outcomes is feasible and instruments to achieve this, such as the SF 36 questionnaire, have potential value in an outpatient setting. IMPLICATIONS--If data on outcomes are to provide a basis for clinical and managerial decision making, information systems will be required to collect, analyse, interpret, and feed it back regularly and in good time. 相似文献
89.
Flexor digitorum profundus avulsions, are well-documented injuries occasionally associated with a distal phalanx fragment. While the injury may involve primarily either tendon or bone, a rarely observed variant combines both tendon and bone avulsions. A type IV variant seen after two sequential injuries is described. 相似文献
90.
R F Meredith M B Khazaeli T Liu G Plott R H Wheeler C Russell D Colcher J Schlom D Shochat A F LoBuglio 《Journal of nuclear medicine》1992,33(9):1648-1653
Twelve patients with metastatic colon cancer were treated with 131I-chimeric B72.3 (IgG-4) at total doses of 28 or 36 mCi/m2 in two or three weekly fractions. Bone marrow suppression was the only significant side effect. The degree of bone marrow suppression adjusted for whole-body dose was modestly but statistically significantly (p = 0.04) less than that seen with identical doses given as a single infusion for the total dose of 36 mCi/m2. Nine of twelve patients developed an antibody response to ch B72.3, which altered the kinetics of radiolabeled antibody in four patients given a second course of therapy. One patient had a minor response that lasted 4 mo. Fractionation of this particular radiolabeled antibody at the dose schedule used produced a modest increase in the therapeutic window in regard to administered dose. 相似文献