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91.
Cerebral fractional oxygen extraction (FOE) was monitored in 30 children, using near infrared spectroscopy during cardiopulmonary bypass, to investigate the effect of hypothermia and circulatory arrest. One group of children (n = 15) underwent profound hypothermia with total circulatory arrest (n = 8) or continuous flow (n = 7). Another group (n = 15), of whom only one had circulatory arrest, underwent mild (n = 6) or moderate (n = 9) hypothermia. The mean FOE (SD) before bypass was 0.35 (0.12) and this correlated negatively with the preoperative arterial oxygen content (r = -0.58). Between the stage of cooling on bypass and cold bypass there was a reduction in FOE in all groups. Between cold bypass and rewarming there was an increase in FOE only in the groups with continuous flow. In the circulatory arrest group, the FOE remained low during rewarming and was significantly lower than that of the continuous flow group. No patients died and none had neurological abnormalities postoperatively. Apparent changes in oxidised cytochrome oxidase concentration were also monitored using near infrared spectroscopy. There was a fall in cytochrome aa3 on starting cardiopulmonary bypass, but there were no significant differences in the changes in cytochrome aa3 between any stage in any of the patient groups. Using this non-invasive technique, cooling was shown to reduce cerebral FOE. During rewarming on bypass there was an increase in cerebral FOE only in patients who had had continuous flow bypass. In contrast, the cerebral FOE in those with circulatory arrest remained constant after arrest and during the duration of the study. This may have implications for the timing of hypoxic brain injury.  相似文献   
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93.
Muitidrug resistant tuberculosis has shown an alarming increase and this assumes added importance in view of the increasing number of HIV infected patients. This article reviews the biomechanism of resistance and discusses the present stategies that are available and recommended to tackle the rising incidence of tuberculosis due to resistant mycobacteria.KEYWORDS: Antitubereular drugs, Drug resistance, Mycobacterium tuberculosis  相似文献   
94.
OBJECTIVE: To estimate prevalence of xerophthalmia and to assess dietary intake of vitamin A in Indian children aged under 6 y. DESIGN: Cross sectional study. STUDY SETTING: Urban slums under Urban Health Centre affiliated to Department of Preventive and Social Medicine, Government Medical College, Nagpur, India. PARTICIPANTS: The study included 1094 all children under 6 y of age, from two randomly selected urban slums. METHODS: Xerophthalmia was diagnosed on the basis of ocular signs and symptoms (WHO recommendations). Dietary intake of vitamin A was assessed by using one year recall method recommended by International Vitamin A Consultative Group. RESULTS: Prevalence of xerophthalmia was estimated to be 8.7%. Nine hundred and ninety-five (90.9%) study subjects were identified as inhabitants consuming dietary vitamin A at below recommended levels. (UPF score < 210). Five hundred and ninety-three (54.2%) study subjects were consuming dietary vitamin A at approximately less than 200 RE/d (UPF score < 120) while 402 (36.2%) were consuming approximately 200-300 RE/d (UPF score 120-210). The prevalence of xerophthalmia was found to be decreasing as the score of usual pattern of food consumption (UPF) increased. CONCLUSIONS: Children with a dietary intake represented by a UPF score of less than 120 were at high risk of developing xerophthalmia, whereas, those consuming vitamin A equal to a UPF score greater than 120 were at comparatively less risk despite being below the recommended levels.  相似文献   
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To see the efficacy of occupational therapy and serial casting over occupational therapy alone in case of sciatic nerve block in cerebral palsy children.In the study 18 spastic cerebral palsy children were treated with in-traneural phenol block (open technique) followed by occupational therapy to bring out functional change. All the 18 patients were administered with intraneural phenol block. In 9 patients serial casting combined with occupational therapy (experimental group) was given while in another group 9 patients were treated with occupational therapy alone (control group). The treatment session for each patient lasted for 6 weeks. To measure the outcome GMFM 66, pediatric balance test (PBT), active range of motion, passive range of motion, modified Ashworth scale were used as tool.There was significant reduction in spasticity of all the 18 patients (after administration of intraneural phenol nerve block) when compared with their pre-operative status. There was significant improvement of gross motor function (GMFM 66), active and dynamic balance (through PBT), and active range of movement of knee joint in experimental group. There was no significant difference between the groups in passive range of motion and reduction of spasticity.The study concludes that intraneural phenol block reduces spasticity in cerebral palsy children to a significant level thus improving the functional outcome in these children. Serial casting when combined with occupational therapy after phenol block gives much better and quicker improvement in gross motor function and motor milestone development.  相似文献   
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98.
Psoriasis is a chronic, systemic inflammatory disorder manifesting primarily in skin and potentially in joints, frequently necessitating treatment with conventional systemic therapies, phototherapy or biological agents. Patients with moderate to severe disease suffer a diminished quality of life, experience significant comorbidities and have a higher mortality. Although traditional treatments are effective in the short‐term, their use is often limited by concerns over long‐term toxicity, including end‐organ damage and risk of malignancy. Combination therapy is a commonly used approach and is often more effective than any single agent. Lower doses of two treatments in combination can also minimize potential side effects from a single agent at higher doses. Etanercept is a recombinant human tumour necrosis factor (TNF)α receptor (p75) protein fused with the Fc portion of IgG1 that binds to TNFα. This article reviews the evidence on the efficacy and safety of etanercept in combination with methotrexate, acitretin, narrowband UVB and cyclosporin. The largest body of evidence assesses the combination with methotrexate, although evidence is available for the other combinations. Data suggest that although highly effective as monotherapy, etanercept in combination with a conventional systemic agent can enhance efficacy and allow drug sparing. Potentially, the combination may also result in faster treatment responses and permit safe transitioning from one systemic agent to another. Evidence to date suggests that these benefits can be achieved without significant additional toxicity, although long‐term data on the efficacy and safety of the combination in psoriatic populations is limited and further evaluation is warranted.  相似文献   
99.
The incidence of Clostridium difficile-associated disease (CDAD) has increased over the past few years and more severe cases of CDAD have been reported. This changing epidemiology is possibly a result of the emergence of a more virulent strain of C difficile that is more resistant to fluoroquinolones and is associated with increased morbidity and mortality. Because of advanced age and frequent courses of antibiotic therapy, patients in long-term care facilities are at increased risk of C difficile infection. In addition to beta-lactams and clindamycin, the fluoroquinolones have recently been associated with increased rates of CDAD. Early identification of C difficile infection and prompt initiation of therapy with the most appropriate agent are critical to minimize morbidity and mortality in this era of increasingly severe CDAD. Metronidazole and vancomycin have been the mainstays of therapy, and recent data support the expanding role of vancomycin in the treatment of severe CDAD. Adjunctive therapy with probiotics, intravenous immunoglobulin, or rifampin has been used in refractory or recurrent CDAD. Adherence to the recommended infection control measures and the judicious use of antibiotics should also be part of the global management of CDAD in long-term care facilities.  相似文献   
100.
The Transfusion Safety Study (TSS) and the National Heart, Lung, and Blood Institute (NHLBI) established a repository of approximately 200,000 sera from blood donors in late 1984 and early 1985. Collections were made in the four metropolitan areas with the highest prevalence of AIDS. Retrospective testing showed an overall anti-HIV-1 prevalence of 16 cases per 10,000 donations. In this study, the predictive value of a negative initial enzyme-linked immunoassay was estimated from both quality control specimens and the rescreening of 13,461 sera to be greater than 99.99 percent with respect to technical error. Among anti-HIV-1-positive persons, there was a 1.3- to 1.5-fold excess of first-time donors. The anti-HIV-1 prevalence among donors showed that infection was more common among young men than suggested by national reporting of AIDS cases. Anti-HIV-1 prevalence varied among the four metropolitan areas less than did reported AIDS cases, but, by 1987, the differences in the latter had decreased. Anti-HIV-1 prevalence in collection areas outside of the four major cities differed much more widely than that among the cities themselves. The TSS/NHLBI Donor Repository will remain available for the indefinite future for further evaluation of screening procedures for HIV-1 and other viruses for which transfusion is found to be an important route of transmission.  相似文献   
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