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91.
PURPOSE OF REVIEW: A review of recent studies was conducted to determine if guidelines promulgated by the American Society of Hematology and the British Committee for Standards in Haematology need to be updated as these were based mainly on expert opinion rather than outcomes derived from clinical trials. RECENT FINDINGS: Recent studies suggest that most patients with immune thrombocytopenic purpura have a disease that is generally well tolerated, with little morbidity. Splenectomy remains the best 'curative' treatment for adults with chronic disease (at least 6 months of follow up). Other treatments such as anti-D, rituximab or dexamethasone may allow the decision of splenectomy to be postponed, possibly indefinitely, if hemostatic platelet count is attained. Mortality from bleeding may be relevant only in patients refractory to splenectomy. Cytotoxic agents should be reserved for patients with bleeding refractory to other treatments. SUMMARY: Patients with platelet counts less than 30 x 10(9)/l or bleeding have to be treated but management decisions should also be based on lifestyle, age, and other medical conditions that may contribute to the risk of serious bleeding. An aggressive therapeutic approach is justified only in patients with platelet counts below 20 x 10(9)/l and those refractory to splenectomy. Newer therapies may be more targeted in their action.  相似文献   
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Q fever may lead to serious complications in chronically infected patients. We report two cases of psoas abscess due to Coxiella burnetii associated with lumbar osteomyelitis secondary to an aortic aneurysmal infection. Diagnosis was based on serology, and PCR detected C. burnetii DNA in an abscess sample.  相似文献   
95.
Whereas the zebrafish retina has long been an important model system for developmental and genetic studies, little is known about the responses of the inner retinal neurons. Here we report single-unit ganglion cell recordings from 5- to 6-day-old zebrafish larvae. In wild-type larvae we identify at least five subtypes of ganglion cell responses to full-field illumination, with ON-OFF and ON-type cells predominating. In the nrc mutant retina, in which the photoreceptor terminals develop abnormally, we observe normal OFF responses but abnormal ON-OFF responses and no ON responses. Previously characterized as blind, these mutants lack an optokinetic reflex (OKR), but in another behavioral assay nrc mutant fish have near-normal responses to the offset of light and slow and sluggish responses to the onset of light. Pharmacological block of the ON pathway mimics most of the nrc visual defects. We conclude that the abnormal photoreceptor terminals in nrc mutants predominantly perturb the ON pathway and that the ON pathway is necessary to drive the OKR in larval zebrafish.  相似文献   
96.
Manganese (Mn), a naturally occurring element present in many foodstuffs, is an essential trace element with many biological functions. In industry, inorganic Mn compounds have a range of different applications, although the majority of Mn is used to make alloys and steel. For the general population, the major source of exposure to Mn is dietary, although drinking water may constitute an additional source in some regions. However, in occupationally exposed humans, inhalation of Mn is likely to be an important additional route. In general, Mn and its inorganic compounds are considered to possess low mutagenic or carcinogenic potential compared with some heavy metals. In this review, an up-to-date analysis of the available published studies on the carcinogenic and genotoxic potential of inorganic Mn is provided (organic Mn compounds are not considered). The current literature indicates that Mn may be weakly mutagenic in vitro and possibly clastogenic in vivo, with unknown genotoxic effects in humans; the possible mechanisms underlying these effects are discussed. The experimental evidence on carcinogenicity (quantitative increase in incidence of thyroid tumors in mice but not rats) does not provide any clear evidence, while the available occupational and environmental epidemiological evidence is equivocal as to whether exposure to inorganic Mn is associated with a significant cancer risk. Hence, it is concluded that there is insufficient evidence to indicate that inorganic Mn exposure produces cancer in animals or humans.  相似文献   
97.

Objectives

A single nucleotide polymorphism (SNP) of the gene encoding protein tyrosine phosphatase type 22 (PTPN22 620W) has recently been described as a strong common genetic risk factor for human autoimmune disease. We have analysed the association of PTPN22 620W in patients with Behçet''s disease (BD).

Methods

Genomic DNA was obtained from 270 patients with BD from the UK and the Middle East. Normal controls (n  =  203) were collected from the same populations. Patients with idiopathic retinal vasculitis from the UK (n  =  136) were used as disease controls. PTPN22 620W was detected by SSP–PCR analysis and agarose gel electrophoresis.

Results

The results showed an inverse correlation between the presence of PTPN22 620W and Behçet''s disease in either patient group tested. There was a greatly reduced prevalence in Middle Eastern compared to UK patients and controls. Finally, there was no association with either UK patients with retinal vasculitis compared with UK controls.

Conclusions

The presence of PTPN22 620W was inversely associated with BD and the distribution of the SNP in the Middle East supports previous findings in the global prevalence.  相似文献   
98.
The aim of this retrospective study is to delineate in Europe the frequency and type of cutaneous manifestations associated with Takayasu arteritis (TA). Eighty patients with TA were analyzed. Symptoms suggestive of Raynaud's syndrome were noted in 11 patients (14%) and could be directly related to large vessel involvement. Other skin lesions were observed in 10 patients (12.5%). Five had acute tender erythematous nodules on the legs with a clinical diagnosis of erythema nodosum; 2 had subacute ulcerated nodules of the legs; 1 had pyoderma-gangrenosum-like ulcerations of the four limbs which resulted from the breakdown of subcutaneous nodules; 1 had lupus-like malar flush, and the last one had urticarial lesions with livedo reticularis. Skin samples were obtained from 4 patients. Three of them agreed that reiterated biopsies be done on recurrent lesions. A granulomatous vasculitis was observed in 2 cases involving hypodermal arterioles in one case and veins in the other. The other pathological findings were septal and lobular panniculitis which can be associated with granulomatous vasculitis. Different histological findings on reiterated biopsies were frequently found. The absence of any other etiology and chronological arguments suggested a relationship between these skin lesions and TA. Tuberculosis was probable in 1 case but apparently was not related to the skin lesions.  相似文献   
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The schooling of young people with cancer poses various problems, similar to those experienced by disabled or chronically ill children. Published data on this subject in the medical literature comes mainly from studies carried out in the USA and the UK. Cancer and its treatment can cause both direct (learning difficulties or other disabilities...) and indirect (discrimination...) problems. Academic failure, and other problems linked to school absenteeism, can affect the future of adolescents with cancer. Sustaining schooling during the illness enables such patients to avoid falling behind academically, and to maintain his or her social status as a student. Due to the organisation of treatment regimes, education is provided in three environments : in hospital (during in-patient stays), at home (generally whilst the patient is convalescing), or at school. Paediatric oncologists have underlined the importance of establishing links between hospital and educational personnel (with parental approval), and suggest that a teachers'illness information manual should be produced. School re-entry is recommended as soon as possible. During the illness, the patient's presence in class is dependent on his or her general health, the progress of the cancer, and the treatment regime being followed. School absenteeism, inevitable during treatment periods and the year following diagnosis, is often associated with academic problems or failure. While many cancer patients worry about their school work and future educational progress, such problems remain rare. In the long term, the educational level of childhood or adolescent cancer survivors remains similar to that of the general population. In order to understand the issues surrounding the schooling of young cancer patients in France, long-term multi-centre studies, focusing on adolescents, must be initiated.  相似文献   
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