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1.
T lymphocyte function was analyzed in patients hemodialyzed with 'high-flux' polysulfone membranes, which have been reported to improve the patients' overall clinical condition and well-being. For comparison purposes, patients treated by the use of 'low-flux' cuprophane membranes were also studied. Peripheral blood white cell counts, numbers of lymphocytes as well as the numbers of T cells and their CD4 and CD8 subsets were within normal range in both patient groups. The absolute number of B cells was slightly decreased in cuprophane-membrane- but not polysulfone-membrane-treated patients. The proliferative response of T lymphocytes after stimulation with optimal concentration of phytohemagglutinin (PHA) was normal in patients treated with 'high-flux' membrane dialysis but significantly reduced in those treated with cuprophane membranes. The generation of interleukin-2 (IL-2) receptor on T lymphocytes after PHA stimulation was normal in the polysulfone-membrane-treated group and slightly impaired in the cuprophane-membrane-dialyzed patients. Production of both IL-2 and interleukin-1, as well as the natural killer cell activity, in patients treated by 'high-flux' membrane dialysis were also comparable to controls. The levels of serum beta 2-microglobulin were significantly elevated in patients-maintained on 'high-flux' dialysis membranes but did not reach the levels seen in patients dialyzed by cuprophane membranes. The beta 2-microglobulin at levels seen in patients on cuprophane dialysis had no effects on activation and proliferation of control lymphocytes in vitro. These results suggest that impaired functional responses of T lymphocytes seen in end-stage disease patients on prolonged hemodialysis with cuprophane membranes are not seen in similar patients hemodialyzed with polysulfone membranes.  相似文献   
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Breast carcinoma is the most common type of cancer affecting women in the Western world. The hereditary forms, which amount from 5 to 10% of all the cases of breast cancer, mainly involve BRCA1 or BRCA2 mutations. Due to the diagnostic strategy used by the patent owner, Direct DNA sequencing (DS) may become the only BRCA1/2 test procedure available, although there exist several alternative strategies. A cost-effectiveness study was carried out using BRCA1 testing as a model. The main techniques available for performing mutation searches were assessed: DS, denaturing high performance liquid chromatography (DHPLC), single-strand conformation polymorphism (SSCP), denaturing gradient gel electrophoresis (DGGE), heteroduplex analysis (HA), fluorescent assisted mismatch analysis (FAMA) and the protein truncation test (PTT). Twenty strategies involving the use of one or more techniques were then devised for performing the complete genetic analysis. DS was adopted as the 'gold standard' for effectiveness. All the strategies except for DS involved a two-step procedure. The first step consisted of pre-screening the 22 coding exons of BRCA1. The second step consisted of performing DS only on the variations detected in the coding sequence. The cost of the strategies tested, including a pre-screening stage, turned out to be 30 to 90% lower than that of DS, whatever annual use was made of the equipment. The most cost-effective strategy, ie, that corresponding to the lowest cost per mutation detected, was found to be a combination between PTT on exon 11 (60% of the coding sequence) and HA on the remaining 21 exons (PTT(11)+ HA(21)). However, since a high false negative rate is associated with this strategy, at least four other strategies are worth mentioning: PTT(11)+ DHPLC(21), DHPLC alone, FAMA(11)+ DHPLC(21) and FAMA alone. Our results on genetic testing for breast cancer show that DS is not the most cost-effective method available. The monopolist approach of the firm which owns the patents on the BRCA1/2 genes, may, therefore limit the use of the most cost-effective strategies.  相似文献   
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Background and purpose: Almost 10% of breast and ovarian cancers are familial, and the majority are linked to BRCA1 and BRCA2 germline mutations. Despite uncertainty about the management of female gene carriers, consensus guidelines have been established to assist practitioners and consultees in making health care decisions.Methodology: The Ad Hoc Committee was composed of 14 experts appointed by the French National Institute for Health and Medical Research, all of whom attended eleven workshops at which more than 3500 articles were systematically analyzed. Five additional experts critically analysed the first version of the report.Criteria and decision process: On a probability scale of the risk of developing breast or ovarian cancers, two thresholds were defined for use in determining whether an intervention would be worthwhile. The first is the threshold above which an intervention can be envisaged or recommended, and the second is the one below which an intervention can be ruled out; between the two, the decision has to be made on a case-by-case basis.Screening and preventive strategies analyzed: With respect to breast cancer: 1) hormonal interventions; 2) primary prevention (diet, family planning and chemoprevention); 3) screening (breast self-examination, clinician breast examination, tumor markers, imaging); 4) prophylactic mastectomy. With respect to ovarian cancer: 1) hormonal stimulation; 2) screening (clinical screening, ultrasound and tumor markers); 3) prophylactic oophorectomy.Main conclusions: For each strategy the following points were addressed: the information to be given to the consultee, the procedure and the indications. In addition, the committee's opinion about BRCA1 and BRCA2 mutation screening is that population-based, or even large-scale, implementation are not justified. Although no scientific evidence is available, the committee feels that specific management is indispensable and advocates the use of defined and evaluated procedures, and participation in clinical trials.  相似文献   
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OBJECTIVES: Fibromyalgia is characterized by diffuse, persistent and unexplained muscle pain associated with tenderness (mechanical allodynia) and unspecific symptoms. Diagnosis criteria as well as pathophysiological mechanisms are still unclear, justifying appropriate questionnaires and clinical investigations. ACTUAL TOPICS: Several questionnaires including visual analogic scales with respect to pain, fatigue, sleep or mood disorders have been used in fibromyalgia such as Fibromyalgia Impact Questionnaire (30 items) and the European List for Fibromyalgia Evaluation (53 items). Similarly several methods have been proposed to evaluate tenderness in fibromyalgia patients: The study of tender points involves their number (normal value < 4/18), or their pain mean intensity score and the sum of their sensitivities defining the tender point index (normal value < 11/72); The average pain threshold (normal value > 4 kg/cm(2)) is more precise, requiring sophisticated devices (mechanical algometers) and physician training; Less complex than pain threshold measurement, more reliable than the tender points number or index, the tensiometer induced myalgia (normal value > 210 mmHg) is probably a promising new alternative way to screen for fibromyalgia. PROSPECTS: Even if further studies are needed, diagnosis approach of fibromyalgia could be improved by new tools such as the European List for Fibromyalgia Evaluation and algotensiometry.  相似文献   
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T cell subsets and cellular immunity in end-stage renal disease   总被引:6,自引:0,他引:6  
The T lymphocyte population was studied by immunofluorescent staining with monoclonal antibodies and laser flow cytometry in the blood of 50 patients with end-stage renal disease undergoing long-term maintenance intermittent hemodialysis. The absolute number of T cells was lower in patients receiving dialysis for more than one year (p less than 0.001), as was the absolute count of helper T cells (p less than 0.005). In patients under 30 years of age, the absolute number of helper T cells was markedly reduced, whereas the number of suppressor/cytotoxic T lymphocytes was not changed. In patients between the ages of 30 and 60 years, both helper and suppressor cells were significantly reduced. In patients over 60 years of age, only the number of helper T cells was reduced. The in vitro response of patients' lymphocytes was reduced both in the mixed lymphocyte reaction (p less than 0.01) and after phytohemagglutinin stimulation (p less than 0.001). Natural killer cytotoxicity of patients' peripheral blood mononuclear cells, however, was unaffected.  相似文献   
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Non-alcoholic fatty liver disease (NAFLD) is among the most common liver diseases. Oxidative stress is one of the pathogenic mechanisms contributing to the progression of simple fatty liver to non-alcoholic steatohepatitis (NASH). Manganese superoxide dismutase (MnSOD) is a mitochondrial antioxidative enzyme and here its expression in rodent and human NAFLD has been analyzed. MnSOD is found reduced in the liver of male mice fed a high fat diet and male ob/ob mice. Female mice fed an atherogenic diet to induce NASH have MnSOD protein levels comparable to controls. In a cohort of 30 controls, 41 patients with fatty liver and 39 NASH patients, MnSOD mRNA is significantly lower in the steatotic and NASH liver. When analyzed in both genders separately reduction of MnSOD expression is only found in males. Here, MnSOD mRNA negatively correlates with steatosis grade but not with extent of fibrosis or inflammation. MnSOD is, however, not reduced in primary human hepatocytes (PHH) treated with palmitate or oleate to increase cellular triglycerides. Lipopolysaccharide, TNF, IL-6, TGFβ and leptin which are all raised in NAFLD do not affect MnSOD in PHH. Adiponectin which attenuates oxidative stress partly by increasing MnSOD in macrophages does not induce MnSOD in PHH. In summary, current data show that hepatic MnSOD is reduced in male but not female humans and rodents with NAFLD.  相似文献   
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ObjectiveWe aimed to formulate a practical clinical treatment algorithm for Holmes tremor (HT) by reviewing currently published clinical data.Materials and MethodsWe performed a systematic review of articles discussing the management of HT published between January 1990 and December 2018. We examined data from 89 patients published across 58 studies detailing the effects of pharmacological or surgical interventions on HT severity. Clinical outcomes were measured by a continuous 1-10 ranked scale. The majority of studies addressing treatment response were case series or case reports. No randomized control studies were identified.ResultsOur review included 24 studies focusing on pharmacologic treatments of 25 HT patients and 34 studies focusing on the effect of deep brain stimulation (DBS) in 64 patients. In the medical intervention group, the most commonly used drugs were levetiracetam, trihexyphenidyl, and levodopa. In the surgically treated group, the thalamic ventralis intermedius nucleus (VIM) and globus pallidus internus (GPi) were the most common brain targets for neuromodulation. The two targets accounted for 57.8% and 32.8% of total cases, respectively. Overall, compared to the medically treated group, DBS provided greater tremor suppression (p = 0.025) and was more effective for the management of postural tremor in HT. Moreover, GPi DBS displayed greater benefit in the resting tremor component (p = 0.042) and overall tremor reduction (p = 0.022).ConclusionsThere is a highly variable response to different medical treatments in HT without randomized clinical trials available to dictate treatment decisions. A variety of medical and surgical treatment options can be considered for the management of HT. Collaborative research between different institutions and researchers are warranted and needed to improve our understanding of the pathophysiology and management of this condition. In this review, we propose a practical treatment algorithm for HT based on currently available evidence.  相似文献   
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