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201.
Implantation of transsclerally sutured posterior chamber lenses is one possibility of surgical visual rehabilitation of eyes with pseudophacic or aphacic bullous keratopathy without zonular-capsular support. We analyzed the results and complications of the surgical procedures performed in our institution. PATIENTS AND METHODS: Out of 1567 penetrating keratoplasties and 220 transsclerally sutured posterior chamber lenses that were performed at our institution between 1991 and 1996, patients that underwent penetrating keratoplasty and sutured posterior chamber lens implantation in whom sufficient clinical information was available were selected and analyzed in a retrospective, nonselective study. Surgery was performed by a total of four surgeons and included anterior vitrectomy, inside-out suturing and synechiolysis if necessary. Detailed pre- and intraoperative data, postoperative course and complications were recorded and analyzed. RESULTS: A total of 96 eyes were analyzed (patient age 17-92 years, 49 male, 46 female). Penetrating keratoplasty was performed for pseudophacic (63) oder aphacic (15) bullous keratopathy or for corneal scars following penetrating injury (18). Mean follow-up was 22 months. In 82 of 96 eyes, visual acuity improved following surgery. Complications included rhegmatogenous retinal detachment in 4 eyes, graft rejection in 5 eyes, secondary angle-closure glaucoma caused by preexisting anterior synechiae in 7 eyes, and persisting cystoid macular edema in 19 eyes. Luxation or subluxation of the IOL and endophthalmitis were not observed in any of the patients. CONCLUSION: Implantation of transsclerally sutured posterior chamber lenses appears to be a safe procedure and is considered by us to be the procedure of choice to correct aphacia during penetrating keratoplasty in eyes with absent zonular-capsular support. The majority of postoperative complications is apparently caused by preexisting problems related to previous surgery and/or trauma, such as peripheral anterior synechiae, vitreous incarceration or cystoid macular edema. 相似文献
202.
MK Coodley GO Coodley W Levinson MR Rosenberg VT Dull 《Canadian Metallurgical Quarterly》1993,153(22):2588-2592
OBJECTIVES: Practicing internists commonly provide gynecologic care, yet internists receive little formal training in ambulatory gynecology. To evaluate current residency training, we surveyed house staff perceptions of their training in gynecology. METHODS: Data were collected from house staff at five Portland, Ore, internal medicine training programs by questionnaire using a Likert scale about training in 24 gynecologic and five nongynecologic internal medicine problems. Responses were compared by level of training, institution, and gender. RESULTS: Responses were received from 195 (89%) of 221 residents. House staff reported less than adequate training in gynecology, particularly in the areas of family planning and medical complications of pregnancy, while reporting much superior training in the traditional medicine problems. CONCLUSIONS: House staff in internal medicine report little training in the diagnosis and treatment of gynecologic problems. Training in family planning may be particularly deficient. Residency programs must seek effective teaching strategies to address this deficiency. 相似文献
203.
GO Romero C Simmons M Yaneshita M Doan BR Thomas RL Rodriguez 《Canadian Metallurgical Quarterly》1998,223(1-2):311-320
Because of its importance to cell function, the free-energy metabolism of the living cell is subtly and homeostatically controlled. Metabolic control analysis enables a quantitative determination of what controls the relevant fluxes. However, the original metabolic control analysis was developed for idealized metabolic systems, which were assumed to lack enzyme-enzyme association and direct metabolite transfer between enzymes (channelling). We here review the recently developed molecular control analysis, which makes it possible to study non-ideal (channelled, organized) systems quantitatively in terms of what controls the fluxes, concentrations, and transit times. We show that in real, non-ideal pathways, the central control laws, such as the summation theorem for flux control, are richer than in ideal systems: the sum of the control of the enzymes participating in a non-ideal pathway may well exceed one (the number expected in the ideal pathways), but may also drop to values below one. Precise expressions indicate how total control is determined by non-ideal phenomena such as ternary complex formation (two enzymes, one metabolite), and enzyme sequestration. The bacterial phosphotransferase system (PTS), which catalyses the uptake and concomitant phosphorylation of glucose (and also regulates catabolite repression) is analyzed as an experimental example of a non-ideal pathway. Here, the phosphoryl group is channelled between enzymes, which could increase the sum of the enzyme control coefficients to two, whereas the formation of ternary complexes could decrease the sum of the enzyme control coefficients to below one. Experimental studies have recently confirmed this identification, as well as theoretically predicted values for the total control. Macromolecular crowding was shown to be a major candidate for the factor that modulates the non-ideal behaviour of the PTS pathway and the sum of the enzyme control coefficients. 相似文献
204.
The influence of applied radiation on the degradation of a polyglycolide (PGA) test specimen was studied in vitro. There was no significant difference in the time-dependent degradation behaviour between the irradiated test specimen and controls. Mandatory irradiation of an operation site following surgery therefore does not contradict the employment of bioresorbable implants in orthopaedic surgery. 相似文献
205.
U Schmidt-Erfurth GO Bastian S Bopp K Lucke H Laqua 《Canadian Metallurgical Quarterly》1994,91(3):357-363
Primary, ocular Non-Hodgkin lymphoma is a multicentric disease. The prognosis is mostly determined by involvement of the central nervous system and/or visceral organs. Since ocular symptoms often precede accompanying manifestations and since the eye is easily accessible to diagnostic measures, the ophthalmological diagnosis is essential for early detection and treatment of this complex disease, which has a poor prognosis. To illustrate the extraordinary heterogeneity of the clinical symptoms, four case reports have been selected which demonstrate various ocular symptoms and extraocular localizations. The ophthalmological variability ranges from typical uveitis to retinitis and vasculitis with varying symptoms during the progression of the disease. Completely different extraocular features were induced by long-standing, local infiltrates within basal ganglia, a diffuse infiltration of the brain leading to an acute increase in intracranial pressure, a peripheral tumour within the spinal channel or massive infiltrates of liver, lung and kidneys. Lack of pathognomonic features, high clinical variability and the limited value of imaging techniques and histopathological measures often lead to serious delays in diagnosis. 相似文献
206.
GO Gabbard 《Canadian Metallurgical Quarterly》1995,43(4):1115-1136
The notion of professional boundaries is a relatively recent addition to psychoanalytic practice. Freud and his early disciples indulged in a good deal of trial and error as they evolved psychoanalytic technique. The study of these early boundary violations illuminates the study of the evolution of the concepts of transference and countertransference. The recent publication of the correspondence between Freud and Jung, between Freud and Ferenczi, and between Freud and Jones has provided us with extraordinary insights into the boundary transgressions that occurred in the early days of psychoanalysis. The boundary violations of the analytic pioneers have contributed to the legacy inherited by future generations of analysts. Institutional resistance to addressing these difficulties in contemporary psychoanalytic practice may relate in part to the ambiguities surrounding boundaries in the training analysis itself. 相似文献
207.
GO Kokwaro 《Canadian Metallurgical Quarterly》1995,72(10):684-687
Elevation of plasma digoxin levels following concurrent administration of nifedipine have previously been reported. The mechanism for this interaction has not been fully explained, but may include a reduction in volume of distribution of digoxin and/or reduction in the renal or non-renal clearance of digoxin by nifedipine. The end result is probably an elevation of plasma concentrations of free (pharmacologically active) digoxin, which may lead to manifestation of side effects of digoxin. This communication highlights the possible pharmacokinetic basis of the reported digoxin-nifedipine interaction. 相似文献
208.
Residues of polychlorinated biphenyls in edible fish of the Adriatic Sea: assessment of human exposure 总被引:1,自引:0,他引:1
ABSTRACT: Food consumption is an important route of human exposure to polychlorinated biphenyls (PCBs). To assess the potential health risks associated with these contaminants due to fish consumption, the muscle tissue of edible species of fish was analyzed. Contamination levels among the different species varied from 134 to 1210 ng/g lipid weight. Isomer-specific analysis revealed a profile dominated by hexa- (57.9% to 82.9%) and pentachlorobiphenyls (10.3% to 23.9%), followed by hepta- (9.0% to 19.2%) and tetrachlorobiphenyls (0.7% to 17.5%). Other congeners, including those with less than 4 or more than 9 chlorine atoms, were below the instrumental limit of detection in all samples. Risk evaluation for human health was carried out by comparing the experimental data with the new European Commission legal level and a new approach proposed by the U.S. EPA to protect population-segments who repeatedly consume fish. The dietary intake of PCBs, as WHO-TEQ per kg body weight (b.w.), was below 8 pg TEQ/kg body weight/week, while the new EPA approach suggested that the chronic effects do not represent any type of danger for human health, while the possible rise in the carcinogenic risk connected with consumption of some type of fish is more worrisome. 相似文献
209.
Levels of polychlorinated biphenyls (PCBs), hexachlorobenzene, hexachlorocyclohexane isomers (alpha, beta, gamma), and chlorinated pesticides (DDTs) in cod-liver oil used as a dietary supplement were determined. Total PCB and DDT concentrations varied from 25 to 201 ng g(-1) lipid weight basis and from 25 to 133 ng g(-1) lipid weight basis, respectively. Hexachlorobenzene contributed very little to the overall contaminant burden of dietary supplement oils, whereas hexachlorocyclohexane isomers were below the instrumental detection limits in all samples. The daily intake of PCBs and DDTs derived by the consumption of cod-liver oil at manufacturer-recommended doses varied from 0.004 to 2.01 microg/day and from 0.004 to 1.24 microg/day, respectively. Relative to some dioxin-like PCB congeners (mono-ortho PCB 105, 118, and 156; non-ortho PCB 77, 126, and 169), the intakes calculated varied from less than 0.001 to 0.74 pg of toxic equivalency values (TEQ) per kg of body weight per day. These values, although below the range of 1 to 4 pg of TEQ per kg of body weight per day set by the World Health Organization, emphasize the need for strict and continuous monitoring of fish oil contamination to reduce, as much as possible, the risks to human health. 相似文献