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101.
Non-obese diabetic NOD/SCID mice have been used to grow human leukaemia as a systemic disease. The animals were inoculated with leukaemic cells obtained from a 36-year-old male with early B-cell precursor acute lymphoblastic leukaemia and on day 15 were given the first of three weekly injections of 1 mg/kg vincristine or equimolar liposomal vincristine. The development of leukaemia in the mice was monitored by taking weekly blood samples and measuring the cell content by flow cytometry. The median time to 50% human cells in the peripheral blood of mice treated with free vincristine was 41 d from the start of treatment compared with 49 d for mice treated with liposomal vincristine (P < 0.01). The median day of death for mice treated with free vincristine was 47 d from the start of treatment and 57 d for mice receiving liposomal vincristine (P<0.01), thus providing a 21% increase in lifespan for animals treated with the liposomal preparation. There was slightly greater weight loss in mice treated with free vincristine than those given liposomal vincristine. Measurement of in vitro colony forming bone marrow progenitor cells in similarly treated, tumour-free mice, showed no difference in progenitor cell survival between mice that received either type of vincristine. We conclude that encapsulating vincristine in liposomes improves the therapeutic index of this drug measured in mice bearing human leukaemia. This may lead to use of the drug in conventional combination chemotherapy with greater safety or, in this setting, at higher dosage.  相似文献   
102.
OBJECTIVE: To determine whether the progression of urinary albumin excretion rate (AER) is higher during puberty than before or after this period. RESEARCH DESIGN AND METHODS: A prospective study was conducted in which normoalbuminuric prepubertal (n = 20), pubertal (n = 28), and postpubertal (n = 26) IDDM groups matched for diabetes duration and long-term metabolic control were followed for 3 years. At 6-month intervals, 24-h urine collection was used to determine AER. RESULTS: AER increased significantly over a period of 3 years in the pubertal (P = 0.001) and postpubertal (P = 0.003) subjects but not in prepubertal subjects. The annual progression of AER was significantly higher in the pubertal group than in the prepubertal (P = 0.001) or postpubertal (P = 0.001) groups. Six pubertal, two postpubertal, and none of the prepubertal subjects developed microalbuminuria (AER > or = 20 micrograms/min on two consecutive occasions) over a 3-year period (P = 0.047). Multiple logistic regression analysis showed that the risk of development of microalbuminuria was increased in pubertal subjects compared with the prepubertal and postpubertal subjects (adjusted relative risk [95% CI]: 4.3 [1.5-9.3], P = 0.012, and 2.1 [1.1-5.0], P = 0.023, respectively). CONCLUSIONS: Puberty represents an independent risk of the development of microalbuminuria in diabetes. This findings suggests that the endocrine changes of puberty lead to an accelerated process of early kidney damage in diabetes. In pediatric diabetes care, screening for microalbuminuria is needed soon after the onset of puberty.  相似文献   
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Aspiration of inflorescence or grass heads (seed head of grasses) often presents with atypical signs and symptoms because grass heads have a tendency to rapidly migrate to the periphery of the lung. If this is not recognized, it can lead to delay in diagnosis and serious complications. Removal with rigid bronchoscopy maybe difficult, and surgery is often needed. We report a case of a seven-month-old child who had a delayed diagnosis of grass head aspiration and subsequently presented with a life threatening tension pneumothorax. This case highlights the importance of obtaining a detailed history in cases of foreign body aspiration and the need to include it in the differential diagnosis of unexplained respiratory symptoms, especially those of sudden onset in children.  相似文献   
105.
Animal studies suggest that lipids are risk factors for kidney diseases. Some prospective studies and clinical trials have reported predictive effects of lipoproteins on different stages of diabetic nephropathy in humans. We examined lipoprotein abnormalities to determine if they predict abnormal urinary excretion of albumin (> or = 30 mg albumin/g creatinine), using logistic regression. We followed 671 American Indians (211 men, 460 women) with Type II diabetes for a mean of 3.9 years (range 1.7-6.2). Participants were aged 45-74 years. They had normal excretion of albumin and normal serum creatinine at baseline. 67 men and 144 women developed abnormal excretion of albumin. In models controlled for age, treatment with oral hypoglycaemic agents or insulin, HbA1c, study site, degree of Indian heritage, mean arterial blood pressure, albumin excretion at baseline and duration of diabetes, a high HDL cholesterol was a protector for abnormal excretion of albumin in women [odds ratio (OR) comparing the 90th with the 10th percentile = 0.56, 95% confidence interval (CI) = 0.32-0.98], but not in men (OR = 1.5, 95% CI = 0.66-3.4). Further adjustment for obesity, insulin concentration, alcohol consumption or physical activity did not change the results. There was a tendency for high values of VLDL and total triglyceride and small LDL size to predict abnormal excretion of albumin in women only. We conclude that low HDL cholesterol was a risk factor for abnormal excretion of albumin in women, but not in men. Sex hormones may be responsible for sex differences in the association between HDL cholesterol and abnormal excretion of albumin.  相似文献   
106.
BACKGROUND: Despite widespread use of aminosalicylates as maintenance treatment for ulcerative colitis (UC), patients still report troublesome symptoms, often nocturnally. AIM: To compare the efficacy and safety of balsalazide (Colazide) with mesalazine (Asacol) in maintaining UC remission. METHODS: A randomized, double-blind comparison of balsalazide 3 g daily (1.04 g 5-ASA) and mesalazine 1.2 g daily for 12 months, in 99 (95 evaluable) patients in UC remission. RESULTS: Balsalazide patients experienced more asymptomatic nights (90% vs. 77%, P=0.0011) and days (58% vs. 50%, N.S.) during the first 3 months. Balsalazide patients experienced more symptom-free nights per week (6.4+/-1.7 vs. 4.7+/-2.8; P=0.0006) and fewer nights per week with blood on their stools or on the toilet paper, mucus with their stools or with sleep disturbance resulting from symptoms or lavatory visits (each P < 0.05). Fewer balsalazide patients relapsed within 3 months (10% vs. 28%; P=0.0354). Remission at 12 months was 58%, in both groups. Similar proportions of patients reported adverse events (61% balsalazide vs. 65% mesalazine). There were five serious adverse events (two balsalazide, three mesalazine) and four withdrawals due to unacceptable adverse events (three balsalazide, one mesalazine), of which one in each group was also a serious adverse event. CONCLUSIONS: Balsalazide 3 g/day and mesalazine 1.2 g/ day effectively maintain UC remission and are equally well tolerated over 12 months. At this dose balsalazide prevents more relapses during the first 3 months of treatment and controls nocturnal symptoms more effectively.  相似文献   
107.
PURPOSE: To review the current literature and generate recommendations on the role of newer technology in the management of the unanticipated difficult airway. METHODS: A literature search using key words and filters of English language and English abstracted publications from 1990-96 contained in the Medline, Current Contents and Biological Abstracts databases was carried out. The literature was reviewed and condensed and a series of evidence-based recommendations were evolved. CONCLUSIONS: The unanticipated difficult airway occurs with a low but consistent incidence in anaesthesia practice. Difficult direct laryngoscopy occurs in 1.5-8.5% of general anaesthetics and difficult intubation occurs with a similar incidence. Failed intubation occurs in 0.13-0.3% general anaesthetics. Current techniques for predicting difficulty with laryngoscopy and intubation are sensitive, non-specific and have a low positive predictive value. Assessment techniques which utilize multiple characteristics to derive a risk factor tend to be more accurate predictors. Devices such as the laryngeal mask, lighted stylet and rigid fibreoptic laryngoscopes, in the setting of unanticipated difficult airway, are effective in establishing a patient airway, may reduce morbidity and are occasionally lifesaving. Evidence supports their use in this setting as either alternatives to facemask and bag ventilation, when it is inadequate to support oxygenation, or to the direct laryngoscope, when tracheal intubation has failed. Specifically, the laryngeal mask and Combitube have proved to be effective in establishing and maintaining a patent airway in "cannot ventilate" situations. The lighted stylet and Bullard (rigid) fibreoptic scope are effective in many instances where the direct laryngoscope has failed to facilitate tracheal intubation. The data also support integration of these devices into strategies to manage difficult airway as the new standard of care. Training programmes should ensure graduate physicians are trained in the use of these alternatives. Continuing medical education courses should allow physicians in practice the opportunity to train with these alternative devices.  相似文献   
108.
A multicenter, open-label prospective trial was performed to determine the clinical and microbiologic efficacy of ofloxacin (OFLX) otic solution in the treatment of subjects > or =12 years with chronic suppurative otitis media (CSOM) and a chronically perforated tympanic membrane in the infected ear(s). A total of 207 patients at 27 centers in the United States and Central America received OFLX 0.5 mL instilled ototopically twice daily for 14 consecutive days. The primary clinical end point was cure (dry ear) or failure (not dry ear). The primary microbiologic end point was eradication of baseline pathogens. Because there was no comparator and there were few data in the literature regarding clinical efficacy in patients treated with other regimens, the efficacy of OFLX was compared with data recorded in the clinical records of historical-practice control (HPC) or current-practice control (CPC) subjects. The incidence of clinical cure in clinically evaluable OFLX-treated patients (91%; 148 of 162 subjects) was significantly higher than in HPC subjects (67%; 124 of 185 subjects) or CPC subjects (70%; 38 of 54 subjects). OFLX eradicated all baseline pathogens isolated in microbiologically evaluable subjects. These pathogens were predominantly Staphylococcus aureus, Pseudomonas aeruginosa, and Proteus mirabilis. The most common treatment-related adverse event, bitter taste, occurred in 17% (35 of 207) of OFLX-treated subjects. Thus OFLX 0.5 mL administered twice daily for 14 days was effective in resolving the signs and symptoms of CSOM in subjects > or =12 years, was significantly more effective than therapies used to treat HPC or CPC subjects, and was well tolerated.  相似文献   
109.
110.
We retrospectively reviewed the cases of seventy-two consecutive patients who had a lumbar discectomy, between 1950 and 1983, when they were sixteen years of age or younger. There were forty boys and thirty-two girls. At the time of the lumbar discectomy, twelve patients (17 per cent) also had a spinal arthrodesis. The mean duration of follow-up was 27.8 years (range, twelve to forty-five years). Twenty patients (28 per cent) had one reoperation or more, with the first reoperation performed at a mean of 9.7 years after the initial discectomy. Fourteen patients had one reoperation, four had two reoperations, one had three, and one had five. Fifty-two patients (72 per cent) did not need a reoperation. At the time of the latest follow-up, forty-eight (92 per cent) of the fifty-two patients either had no pain or had occasional pain related to strenuous activity and fifty-one (98 per cent) could participate in daily activities with no or mild limitations. Survivorship analysis showed that the overall probability that a patient would not need a reoperation was 80 per cent at ten years and 74 per cent at twenty years after the initial operation. With the numbers available for study, we could not show that age, gender, or an arthrodesis performed at the time of the initial operation were risk factors for a reoperation. We could not detect a difference, with respect to pain or the level of activity, between the patients who had had an arthrodesis at the initial operation and those who had not or between those who had a coexisting structural abnormality of the lumbar spine and those who did not.  相似文献   
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