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71.
Malignant external otitis is an infection of the external ear canal, mastoid, and base of the skull caused by Pseudomonas aeruginosa. The condition occurs primarily in elderly patients with diabetes mellitus. Current theories on pathogenesis and anatomic correlations are reviewed. Severe, unrelenting otalgia and persistent otorrhea are the symptomatic hallmarks of the disease, whereas an elevated erythrocyte sedimentation rate is the only distinctive laboratory abnormality. Iatrogenic causes such as administration of broad-spectrum antibiotics and aural irrigation may play a predisposing role in high-risk populations. The disease can result in cranial polyneuropathies (with facial nerve [VII] paralysis being the most common) and death. The mainstay of treatment is administration of antipseudomonal antibiotics for four to eight weeks. Recurrence is common, and mortality remains at about 20 percent despite antibiotic therapy. Given the increasing longevity of diabetic patients, the frequency of this disease is increasing. Internists, family practitioners, and ambulatory care physicians must now be cognizant of the presenting symptoms, while infectious disease specialists and otolaryngologists need to be appraised of strides in diagnosis and therapy. The role of surgery should be minimized. Use of new diagnostic radiologic modalities and new antipseudomonal antibiotics discussed in this review should lead to improved outcome.  相似文献   
72.
This review describes the evolution of research into the genetic basis of how different organisms use the process of excision repair to recognize and remove lesions from their cellular DNA. One particular aspect of excision repair, DNA incision, and how it is controlled at the genetic level in bacteriophage, bacteria, S. cerevisae, D. melanogaster, rodent cells and humans is examined. In phage T4, DNA is incised by a DNA glycosylase-AP endonuclease that is coded for by the denV gene. In E. coli, the products of three genes, uvrA, uvrB and uvrC, are required to form the UVRABC excinuclease that cleaves DNA and releases a fragment 12-13 nucleotides long containing the site of damage. In S. cerevisiae, genes complementing five mutants of the RAD3 epistasis group, rad1, rad2, rad3, rad4 and rad10 have been cloned and analyzed. Rodent cells sensitive to a variety of mutagenic agents and deficient in excision repair are being used in molecular studies to identify and clone human repair genes (e.g. ERCC1) capable of complementing mammalian repair defects. Most studies of the human system, however, have been done with cells isolated from patients suffering from the repair defective, cancer-prone disorder, xeroderma pigmentosum, and these cells are now beginning to be characterized at the molecular level. Studies such as these that provide a greater understanding of the genetic basis of DNA repair should also offer new insights into other cellular processes, including genetic recombination, differentiation, mutagenesis, carcinogenesis and aging.  相似文献   
73.
The aims of this study were (1) to elicit the users' responses to four electronic head-mounted devices (Jordy, Flipperport, Maxport and NuVision) and (2) to correlate users' opinion with performance. Ten patients with early onset macular disease (EOMD) and 10 with age-related macular disease (AMD) used these electronic vision enhancement systems (EVESs) for a variety of visual tasks. A questionnaire designed in-house and a modified VF-14 were used to evaluate the responses. Following initial experience of the devices in the laboratory, every patient took home two of the four devices for 1 week each. Responses were re-evaluated after this period of home loan. No single EVES stood out as the strong preference for all aspects evaluated. In the laboratory-based appraisal, Flipperport typically received the best overall ratings and highest score for image quality and ability to magnify, but after home loan there was no significant difference between devices. Comfort of device, although important, was not predictive of rating once magnification had been taken into account. For actual performance, a threshold effect was seen whereby ratings increased as reading speed improved up to 60 words per minute. Newly diagnosed patients responded most positively to EVESs, but otherwise users' opinion could not be predicted by age, gender, diagnosis or previous CCTV experience. User feedback is essential in our quest to understand the benefits and shortcoming of EVESs. Such information should help guide both prescribing and future development of low vision devices.  相似文献   
74.
BACKGROUND: We evaluated historical trends in the Staphylococcus aureus infection rate, economic burden, and mortality in US hospitals from 1998 through 2003. METHODS: The Nationwide Inpatient Sample was used to assess trends over time of S. aureus infection during 1998-2003. Historical trends were determined for 5 strata of hospital stays, including all inpatient stays, surgical procedure stays, invasive cardiovascular surgical stays, invasive orthopedic surgical stays, and invasive neurosurgical stays. RESULTS: During the 6-year study period from 1998 through 2003, the rate of S. aureus infection increased significantly for all inpatient stays (from 0.74% to 1.0%; annual percentage change (APC), 7.1%; P=.004), surgical stays (from 0.90% to 1.3%; APC, 7.9%; P=.001), and invasive orthopedic surgical stays (from 1.2% to 1.8%; APC, 9.3%; P<.001). For invasive neurosurgical stays, the rate of S. aureus infection did not change from 1998 to 2000 but increased at an annual rate of 11.0% from 2000 to 2003 (from 1.4% to 1.8%; P=.034). The total economic burden of S. aureus infection for hospitals also increased significantly for all stay types, with the annual percentage increase ranging from 9.2% to 17.9% (P<.05 for all). In 2003, the total economic burden of S. aureus infection was estimated to be $14.5 billion for all inpatient stays and $12.3 billion for surgical patient stays. However, there were significant decreases in the risk of S. aureus-related in-hospital mortality from 1998 to 2003 for all inpatient stays (from 7.1% to 5.6%; APC, -4.6%; P=.001) and for surgical stays (from 7.1% to 5.5%; APC, -4.6%; P=.002). CONCLUSIONS: The inpatient S. aureus infection rate and economic burden of S. aureus infections for US hospitals increased substantially from 1998 to 2003, whereas the in-hospital mortality rate decreased.  相似文献   
75.
BACKGROUND: The mainstay of treatment for pemphigus is systemic corticosteroids. Different adjuvants have been used to reduce side-effects of long-term corticotherapy. Gold is an anti-inflammatory drug used in autoimmune diseases, whose use has waned with the advent of new immunosuppressive agents. OBJECTIVE: To study the outcome of the use of intramuscular gold treatment of pemphigus vulgaris refractory to previous therapies. METHODS: Thirteen patients with pemphigus vulgaris who had failed to respond to several prior therapies were treated with aurothiomalate, as a steroid-sparing agent. Patients were monitored to assess disease activity and gold toxicity. RESULTS: Seven patients achieved complete remission. Four patients were able to taper prednisone doses, although pemphigus flared when prednisone was discontinued or reduced. Toxicity was observed in the other two patients. CONCLUSIONS: In 53.4% of the patients, the use of chrysotherapy resulted in the complete clearing of the disease, discontinuation of all systemic therapies and induced a long-term clinical remission. Prednisone doses were able to be reduced in the remaining 46.6%. Any side-effects were reversible with drug discontinuation. Gold therapy showed efficacy as a secondary line treatment in refractory pemphigus vulgaris.  相似文献   
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78.
BACKGROUND: Equilibration of hemoglobin concentration after transfusion has been estimated to take about 24 hours, but some studies have shown that earlier measurements reflect steady-state values in persons who have not bled recently. This study was aimed at assessing the changes over time in hemoglobin concentration after transfusion in acutely anemic patients because of recent bleeding. STUDY DESIGN AND METHODS: Thirty-two normovolemic patients recovering from an acute bleeding episode who were no longer thought to be bleeding and who received a 2- unit red cell transfusion were studied. At baseline and 15, 30, 60, and 120 minutes and 24 hours after transfusion, hemoglobin concentration and hematocrit values were measured. RESULTS: The administration of 2 units of packed red cells elicited a 24-hour increase of 22.4 +/− 6.8 g per L in hemoglobin concentration. Hemoglobin values were not different at any of the defined posttransfusion times. Hematocrit levels experienced similar changes over time. Agreement between 15-minute and 24-hour values was excellent, as only 6 percent of patients exhibited a clinically significant difference (> 6 g/L) between the hemoglobin measurements. CONCLUSION: Hemoglobin and hematocrit values rapidly equilibrate after transfusion in normovolemic patients who are recovering from an acute bleeding episode. This fact would allow a rapid assessment of the effects of transfusion and of the recurrence of bleeding in patients remaining at risk.  相似文献   
79.
The case is described of a 73 year old man who presented with a lupus-like syndrome related to treatment with isoniazid and had IgG antinuclear antibodies against the nucleo-histone complex (H2A-H2B)-DNA. After a short course of treatment with prednisone and discontinuation of isoniazid the patient's lupus symptoms resolved and a gradual decrease in antibodies to (H2A-H2B)-DNA occurred. This case suggests that isoniazid is capable of inducing an autoantibody specificity associated with drug related lupus.  相似文献   
80.
The developmental stage of adolescence may be so turbulent as to require psychiatric intervention. The adaptive difficulties experienced by Offer's tumultuous group of adolescents were once considered normal problems for that age group. Now they are considered to be a precursor to more serious psychosocial problems and require entry into the mental health care system. The adolescent psychiatric patient may experience adaptive difficulties, such as delinquency, substance abuse, and sexual acting out, or a diagnosed psychiatric disorder. The level of care an adolescent requires depends upon the type and severity of his dysfunction. Early detection and prevention is largely accomplished through education. Assessment and crisis intervention require the structure of an acute care inpatient setting. Long-term treatment may be necessary to provide a corrective emotional experience for the severely dysfunctional adolescent. Research endeavors should be directed toward further exploration of the relationship between adaptive difficulties and adult psychiatric disorder. Outcome studies would be helpful in evaluating the success of psychiatric nursing intervention at multiple levels of complexity.  相似文献   
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