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931.
AIMS: To determine whether "herbal creams" reported as being effective for the treatment of childhood atopic eczema contained corticosteroids. METHODS: Patients attending the paediatric dermatology clinic at Birmingham Children's Hospital, April 2001 to March 2002, and who reported using "herbal creams" with good effect for atopic eczema were asked to submit the cream for analysis. Hydrocortisone, clobetasone butyrate, betamethasone valerate, and clobetasol propionate were analysed by HPLC. RESULTS: Twenty four creams from 19 patients, median (interquartile range) age 3.82 (0.69-7.98) years were analysed. All five creams labelled Wau Wa and the two labelled Muijiza cream contained clobetasol propionate. Thirteen of 17 unnamed creams contained corticosteroids: clobetasol proprionate (n = 4), clobetasol proprionate + hydrocortisone (n = 1), betamethasone valerate (n = 2), clobetasone butyrate (n = 3), and hydrocortisone (n = 2); there was an unidentified peak in one. Further analysis suggested Wau Wa cream contained approximately 20% proprietary Dermovate Cream in a paraffin base. No parents were aware that the creams contained steroid. CONCLUSIONS: The majority of herbal creams analysed illegally contained potent or very potent topical steroids. There is an urgent need for tighter regulation of herbal creams and for increased public education about the potential dangers of alternative therapies. 相似文献
932.
933.
Abnormal T-cell function in B-cell chronic lymphocytic leukaemia 总被引:6,自引:0,他引:6
There is increasing evidence of T cell dysfunction in B cell chronic lymphocytic leukaemia (B-CLL) which may contribute to the aetiology and progress of the disease. An absolute CD8+ lymphocytosis correlates with disease progression and low expression of CD4 and CD8 (as found in autoimmune disease) is seen with abnormal expression of other surface molecules. Although the expression of T cell surface activation markers, CD25 and CD152, may be increased on culture in B-CLL serum, response to the common mitogens, PHA and PWM, is reduced. This and the excess of CD8 cells may explain partly the variable cooperation of T cells with B cell production of immunoglobulin in B-CLL. In the context of T cell cross-talk with antigen presenting cells, B-CLL B cells are poor antigen presenters. But the T cells themselves have significant abnormalities of expression of the many antigens and ligands necessary for this process. In particular, they exhibit variable expression of the low affinity and non-specific adhesion molecules LFA-1 and ICAM-1, variable, clonally restricted and skewed expression of the TCR repertoire (implying repeated antigenic stimulation possibly by CLL antigens), reduced CD28 and CD152 expression (implying impairment of ability to start or stop an immune response) and reduced IL2 and CD25 (IL2 R) expression (critical for positive feed-back in maintenance and expansion of the T cell response to antigen presentation). Although the production of IL2 and other cytokines by the T cell in B-CLL may be impaired, production of the anti-apoptotic cytokine IL4 is not and there may be a unique and expanded subset of CD8/CD30 cells capable of releasing IL4. The relationship of this T cell subset to the malignant B cell in vivo is unknown. However, T cells which are CD4+/CD152+/CCR4+ migrate selectively in vitro in response to the chemokine CCL22 (specific for the receptor CCR4) produced by the malignant B cells and are always seen amongst the malignant cells in bone marrow and lymph nodes from B-CLL patients. Other abnormalities of cytokine secretion are described. These findings suggest that the T cell in B-CLL may be unable to start, maintain and complete an immune response to the malignant B cell and other antigens and may be involved directly in sustaining the tumour. However, autologous tumour specific cytotoxicity has been shown in vitro and T cells which recognise tumour-derived heavy chain fragments circulate in vivo . If adoptive immunotherapy of any nature is to succeed in B-CLL, manipulation to optimise these CTL responses is needed to overcome the profound and variable T cell dysfunction in this disease. 相似文献
934.
935.
Gordon SB Kanyanda S Walsh AL Goddard K Chaponda M Atkinson V Mulwafu W Molyneux EM Zijlstra EE Molyneux ME Graham SM 《Emerging infectious diseases》2003,9(6):747-749
Streptococcus pneumoniae infections can be prevented by using new conjugate vaccines, but these vaccines have limited serogroup coverage. We report the first serogrouping data from carried and invasive isolates obtained from children and adults in Malawi. The 7-valent vaccine would cover 41% of invasive isolates from children and 25% from adults. A 9-valent vaccine, including types 1 and 5, would cover 66% of invasive isolates from children and 55% from adults. 相似文献
936.
937.
Current attitudes to total hip replacement in the younger patient: results of a national survey 下载免费PDF全文
A postal questionnaire was sent to all practicing consultant orthopaedic surgeons in the UK seeking information regarding their usual total hip replacement practice, the age at which they would define a patient as falling into the 'young hip group' and whether this might modify their practice. In particular, in the 'younger' age group, we were interested in the frequency of usage of uncemented implants, the choice of implant and the bearing surfaces. Of 1242 surgeons surveyed, we had a response from 935 who currently undertake total hip arthroplasty. Their responses confirm that approximately 60,645 total hip replacements are performed annually in the UK of which 9,376 are performed in the younger age group (mean age 57.5 years). As with our previous survey, the most popular prosthesis in the 'older' age group overall was the Charnley (51%) followed by the Exeter (15%). These implants also proved to be the most popular in the 'younger' age group (40% Charnley, 18% Exeter), with 75% of surgeons choosing a cemented stem, and 65% also opting to cement the socket. 23% of surgeons used hydroxy-apatite coated implants on both the femoral and acetabular sides of the joint. Stainless steel remained the most popular choice of femoral head bearing surface (42%) followed by chrome-cobalt (33%) and ceramic (25%). On the acetabular side, high density polyethylene predominated--accounting for 95%, with only 3% using chrome cobalt and 2% ceramic. There would appear to be a remarkably conservative attitude among British surgeons, the majority of whom prefer to stick with tried and tested cemented femoral implants when dealing with the younger patient. There are a small number of uncemented acetabulae and the hybrid configuration. Hydroxy-apatite coatings seem to be the most popular choice for the non-cemented prostheses. Ceramic femoral heads are used more frequently than the ceramic acetabular bearing, and equally metal/metal bearings remain infrequently used. 相似文献
938.
939.
Transplantation of Mouse Embryonic Stem Cells into the Cochlea of an Auditory-Neuropathy Animal Model: Effects of Timing after Injury 总被引:1,自引:0,他引:1
Hainan Lang Bradley A. Schulte John C. Goddard Michelle Hedrick Jason B. Schulte Ling Wei Richard A. Schmiedt 《Journal of the Association for Research in Otolaryngology》2008,9(2):225-240
Application of ouabain to the round window membrane of the gerbil selectively induces the death of most spiral ganglion neurons and thus provides an excellent model for investigating the survival and differentiation of embryonic stem cells (ESCs) introduced into the inner ear. In this study, mouse ESCs were pretreated with a neural-induction protocol and transplanted into Rosenthal's canal (RC), perilymph, or endolymph of Mongolian gerbils either 1-3 days (early post-injury transplant group) or 7 days or longer (late post-injury transplant group) after ouabain injury. Overall, ESC survival in RC and perilymphatic spaces was significantly greater in the early post-injury microenvironment as compared to the later post-injury condition. Viable clusters of ESCs within RC and perilymphatic spaces appeared to be associated with neovascularization in the early post-injury group. A small number of ESCs transplanted within RC stained for mature neuronal or glial cell markers. ESCs introduced into perilymph survived in several locations, but most differentiated into glia-like cells. ESCs transplanted into endolymph survived poorly if at all. These experiments demonstrate that there is an optimal time window for engraftment and survival of ESCs that occurs in the early post-injury period. 相似文献
940.
Teleradiology is the electronic transmission of radiographic images from one geographic location to another for the purposes of diagnosis and/or consultation. It raises interesting ethical and practical issues which have received relatively little attention in the radiology or ethics literature to date. These include confidentiality, data security and technological reliability, consent, competence, interprofessional and professional-patient relationships, and the organization of medical services. This paper reviews these issues, discussing how far these are new concerns in radiological practice, and makes suggestions for minimum ethical and professional standards for teleradiological practice. 相似文献