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31.
Several areas related to the use of telescopes in low vision are reviewed. These include: contrast sensitivity function; eccentric viewing through a telescope; field of view; telescope used in reverse; and IOL-spectacle lens telescopic systems. Experimental data are included to support selected clinical observations routinely made by low vision clinicians.  相似文献   
32.
 Dermal exposures of methanol were administered in a clinical study designed to compare several biological indicators. Four subjects were exposed in five exposure sessions of varying length. In each session, a sequence of measurements of methanol concentrations in blood, breath, and headspace samples of air at exposed and unexposed skin were collected before and after dermal exposures. Skin headspace samples, collected in gas sampling bags, were designed to reflect equilibrium skin: air partitioning. At exposed skin, headspace samples were highly elevated for at least 8 h following exposure, indicating the presence of a methanol reservoir in skin. After exposure, methanol concentrations at exposed skin showed a rapid initial decline, then a slower first-order decrease. Methanol concentrations were clearly detectable in headspace samples at unexposed skin. Substantial transfer from exposed skin occurred due to mechanical contact and washing. When transfer was restricted, surface concentrations at unexposed skin were similar to levels in breath and were strongly correlated to methanol concentrations in blood. While results are preliminary due to the small sample sizes and several unresolved experimental issues, the simple, rapid, and noninvasive skin headspace measurements appear useful as a biological exposure indicator that clearly shows the presence and site of a dermal exposure, and measurements at unexposed skin reflect concentrations in blood. Received: 14 March 1995/Accepted: 3 November 1995  相似文献   
33.
The Swedish Knee Arthroplasty Register has data on 4, 381 primary operations performed 1985-1995 for rheumatoid arthritis. Of these, 192 were performed with unicompartmental prostheses and 4143 with tricompartmental. 77% were women and the mean age was 66 years. There were 126 first, 20 second, and 1 third revision in tricompartmental arthroplasties, mainly for loosening, infection and patellar problems. There were 38 first, 3 second, and 1 third revision in unicompartmental arthroplasties, mainly for progression of RA and loosening .

Cumulative revision rates (Kaplan-Meier) were calculated. Tricompartmental knees had a 10-year cumulative revision rate of 5% and uni-knees 25%. Patients treated before 1990, men and patients younger than 55 had higher revision rates than patients treated after 1990, women and older patients, respectively. Cemented tibial components resulted in lower revision rates than uncemented ones. There was no significant difference in revision rates between patellar replaced and unreplaced knees or between the 9 commonest implant types.  相似文献   
34.
Background: Studies have consistently confirmed the benefit of liver resection for metastatic colorectal cancer. Few reports, however, have a long enough followup or sufficient 5-year survivors to study the clinical course of patients beyond 5 years.

Study Design: From July 1985 through December 1991, 456 patients underwent liver resection for colorectal metastases. Ninety-six actual 5-year survivors (21%) were identified and their clinical course retrospectively reviewed.

Results: Five-year survivors (n = 96) were more likely to have a Duke’s B primary colorectal carcinoma, fewer than four metastatic lesions, unilobar disease, and a negative histologic margin when compared with patients not surviving 5 years (n = 298). Forty-four (46%) of the 96 five-year survivors had a recurrence after hepatectomy. Of these 44, 19 (43%) were rendered disease free after further treatment. Overall, 71 of the 96 five-year survivors were free of disease at last followup. The actuarial 10-year survival of this group was 78%.

Conclusions: Patients that are disease free 5 years after liver resection are likely to have been cured by liver resection. Patients should be aggressively followed for recurrence because of the potential for further treatment and longterm survival.  相似文献   

35.
Fungal infections still represent a serious complication after organ transplantation. Early diagnosis and aggressive treatment are crucial. Because of the many diagnostic problems involved, we present a case of mucormycosis--primarily affecting the paranasal sinuses with later intracranial extension--in a highly immunized recipient of a third renal transplant. Although fungal infection was suspected from various imaging techniques, only the detection of typical fungal hyphae in the infected tissue was diagnostic. Neither the blood tests and cerebrospinal fluid examinations performed nor cultures from maxillary sinus fluid were of any diagnostic help. Surgical debridement from a transnasal as well as an intracranial approach and systemic amphotericin B together with the discontinuation of immunosuppression after removal of the rejected graft were able to save the patient. This case stresses the importance of early diagnosis that can only be made from tissue biopsies and allows appropriate timely treatment.  相似文献   
36.
The dermatologist's procedure was introduced in 1972 by employers' liability insurance funds in the industrial, agricultural and public sectors of Germany's statutory occupational accident insurance as a "procedure for early detection of occupational skin diseases". So far, it is still the most relevant tool for secondary prevention in occupational dermatology in Germany. According to the intention of this procedure, insured persons with a skin disease in which an occupational aetiology is suspected must be offered preventive measures and, if necessary, given appropriate treatment to avoid their losing their jobs. On the initiative of the Central Federation of Industrial Professional Associations (HVBG), a study group was set up in 1999 from among its membership in cooperation with the Working Committee of Occupational and Environmental Dermatology (ABD) and the Professional Organisation of German Dermatologists (BVDD) to improve on the efficiency of the "classic" dermatologist's procedure. The proposed "optimised" dermatologist's procedure is based on the assumption that early detection followed by competent and intensified skin protection and skin care will be successful in retarding or stopping the progression of occupational dermatoses, while later treatment is likely to be less effective. In October 2002, a pilot study started in Northwest Germany to establish by scientific evaluation whether the implementation of secondary protective measures is definitively better when the provisional "optimised" dermatologist's procedure is followed. The study results should allow detailed suggestions for an improved dermatologist's procedure before it is introduced nationwide.  相似文献   
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Complex injuries of the foot are often overlooked, especially in the multiple injured patient, and they then lead to major loss of function. When the mechanism of injury suggests involvement of the foot, a clinical examination of the lower extremities should be included in the primary diagnostic procedures implemented in the multiply injured patient, followed by radiological examination once the patient's condition is stable. The condition of the soft tissues is of decisive importance in the prognosis of complex foot injuries, regardless of whether the damage to the foot is one component of a polytrauma or an isolated injury, which can also be life threatening. The diagnostic examinations selected should be adapted to the severity of the injuries in the particular multiply injured patient. Successful therapy involves stable internal fixation of injuries to bones and joints, though the external fixation options should be considered in the first instance, and carefully selected methods of temporary and definitive soft tissue reconstruction. The aim of treatment is the best possible reconstruction of the foot as a functional weight-bearing unit with intact soft tissue cover and a natural form. Good results can be achieved when there is close interdisciplinary cooperation between trauma (orthopedic) and plastic surgeons. Patient with severe injuries of this kind should be transferred to a trauma center as the first step toward this end.  相似文献   
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