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101.
Methyl oleate ozonide, a proposed intermediary in ozone intoxication, produced Heinz body inclusions in human erythrocytes at concentrations of from 10?4 to 2×10?3 M. Daily oral supplementation with either 100 mg or 200 mg of d-α- tocopheryl acetate prevented Heinz body formation by methyl oleate ozonide.

These observations suggest that the protective effects of vitamin E against ozone-produced toxicants occurs in man as well as in animals.  相似文献   
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105.
Most cell phone owners use the short message service (SMS), also known as “texting.” Most teens and young adults use text messages; they were the first users to embrace this technology and are still the most frequent users. Text messaging has the potential to provide them with information about preventing sexually transmitted infections. Several innovative programs that use text messaging to promote sexual health are described here.  相似文献   
106.
This paper describes two patients who developed macroscopically and microscopically typical pseudomembranous colitis without prior exposure to antimicrobial agents and without detectable Clostridium difficile or its toxin in the faeces.  相似文献   
107.
BACKGROUND: Members of the European Society of Paediatric Nephrology (ESPN) initiated a study of the demography and policy of paediatric renal care among European countries at the end of the 20th century. METHODS: A questionnaire was mailed to the presidents of each of 43 national renal paediatric societies or working groups in Europe. Data on each country's population, income as reflected by its gross national product and infant mortality rate, were obtained from the United Nations. The paediatric health care systems were previously divided into three types: general practitioner care system, paediatric care system and combined care system (CCS). RESULTS: In 1998, 842 specialized paediatric nephrologists worked in hospitals in 42 European countries. The median number of paediatric nephrologists per million child population (pmcp) was 4.9 (range 0-15). The median number of children served per paediatric nephrologist was significantly higher in countries with the general practitioner care system than in those with the paediatric or combined care system (CCS), namely 370 747 vs 169 456 and 191 788, respectively. In addition to specially trained paediatric nephrologists, there were 1087 paediatricians with a part-time interest/activity in paediatric nephrology in hospitals in 34 European countries. Eastern European countries had significantly more general paediatricians with part-time nephrological activities than countries belonging to the European Union (EU), 16.7 vs 6.6 pmcp. In 1998, 92% of 42 European countries offered paediatric dialysis facilities for acute renal failure and 90% for chronic renal failure and 55% offered paediatric renal transplantation (RTx). Only 30% of Eastern European countries (central omitted) offered paediatric RTx vs 87% of EU countries. The availability of paediatric RTx was associated significantly with the countries' gross national product (r = 0.53, P<0.001). The median number of paediatric hospitals offering dialysis for childhood chronic renal failure was 1.5 pmcp (range 0-5.0) and the median number of paediatric hospitals offering paediatric RTx was 0.4 pmcp (range 0-3.5). Fewer children were on dialysis or were transplanted in Eastern European countries than in the EU. CONCLUSIONS: At the end of the 20th century, there was a marked variation in delivery of paediatric renal care within Europe. This was related to factors such as size of the population, geographical and political situation, the type of primary paediatric care system and economic situation. European countries were far from equal with regard to access of renal replacement therapy for children. Improvement of the economic situation is beyond the capabilities of paediatric nephrologists. However, in these days of world-wide globalization paediatricians in greater Europe should be able to achieve better cooperation and exchange of ideas and information which would be the first step towards equality of renal care for children.  相似文献   
108.
109.

Purpose

Modulation of the immune system by the CNS may involve serotonergic regulation via the brain serotonin transporters (SERT). This regulation may be disturbed in patients with CNS disorders including multiple sclerosis (MS). Central serotonergic mechanisms have not been investigated in MS by in vivo imaging. The objective of the study was to assess the availability of SERT in antidepressant-naive patients with MS by means of PET.

Methods

Included in this study were 23 patients with MS and 22 matched healthy volunteers who were investigated with PET and the SERT-selective marker [11C]DASB, and distribution volume ratios were determined. Clinical assessment of the patients included the expanded disability status scale, the MS fatigue scale Würzburger Erschöpfungsinventar bei MS (WEIMuS) and the Beck Depression Inventory (BDI). The PET data were analysed with both volume-of-interest and voxel-based analyses to determine regional SERT availability.

Results

Patients had lower SERT availability in the cingulate cortex, the thalamus and the insula, and increased availability in the orbitofrontal cortex. Patients with relapsing/remitting MS tended to have lower SERT in the hippocampus, whereas patients with primary progressive disease showed increased SERT availability in prefrontal regions. There was a positive correlation between SERT availability in the insula and both depression and fatigue scores (r?=?0.56 vs. BDI, p?=?0.02; r?=?0.49 vs. WEIMuS, p?=?0.05).

Conclusion

Serotonergic neurotransmission in MS patients is altered in limbic and paralimbic regions as well as in the frontal cortex that this appears to contribute to psychiatric symptoms of MS.  相似文献   
110.
Schorlemmer S  Ignatius A  Claes L  Augat P 《BONE》2005,37(4):491-496
INTRODUCTION: Little is known about the effects of steroids on cortical bone. The purpose of this study was to explore the effects of glucocorticoid treatment on cortical bone density, strength, and formation of new bone in ovariectomized sheep and to compare it to cancellous bone. MATERIALS AND METHODS: Sixteen ovariectomized merino sheep either received a 6-month glucocorticoid treatment (GLU; 0.45 mg/kg/day Methylprednisolone s.c.) or were left untreated (control). After 2 and 4 months, newly formed bone was labeled by the administration of calceingreen and Tetracycline-hydrochloride. After 12 months, the animals were sacrificed and cortical specimens were obtained from the tibial diaphysis. Cancellous bone specimens were harvested from the proximal tibia. All specimens were scanned for apparent BMD by pQCT and tested mechanically. Formation of new bone was analyzed using histological slices of the femoral condyles and cross-sections of the mid-diaphysis of the tibia. RESULTS: The intracortical formation of new bone in glucocorticoid-treated sheep was 70% lower after 2 months and 80% lower after 4 months. Six months after the termination of the steroid administration, the active bone area was 20% lower than in the control group. Cortical width and cortical bone area were reduced by 7-8% and marrow area increased by 8% in steroid-treated animals compared to control animals. Neither cortical apparent bone mineral density nor biomechanical parameters of cortical bone specimens differed between the groups. Cancellous bone formation in steroid-treated animals declined by 68% after 2 months and by 90% after 4 months. After 1 year, cancellous bone formation was reduced by 38% compared to control. The apparent cancellous bone mineral density and cancellous bone compressive stiffness were reduced by 34% and 55%, respectively. CONCLUSION: A six-month glucocorticoid treatment of ovariectomized sheep resulted in a substantial reduction of bone formation both in cortical and in cancellous bone and reduced cortical width by increased endosteal resorption. Beyond changes in cancellous bone, impaired cortical bone remodeling may add to the increased fracture risk at the hip or the distal radius in patients treated with steroids.  相似文献   
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