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We retrospectively evaluated 401 selected patients who had estrogen receptor (ER) assays both at primary surgery and at relapse in an accessible site to determine the clinical relevance of the subsequent ER determination. The median time between ER assessments was 27 months (range: 2-122 months). The median follow-up time from diagnosis was 6 years (range: 2-12 years). For patients with ER+ tumors at primary diagnosis, 29% (76/261) had ER- tumors at relapse, while for ER- primaries, the conversion rate was 33% (46/140). Conversions from ER+ to ER- occurred more often when the time interval between assays was less than one year (p = 0.004), while conversions from ER- to ER+ tended to occur late (beyond three years; p = 0.0003). Treatments received between assays (usually adjuvant therapy) had only a slight influence on ER status conversion. Post-relapse survival was poor for patients who had the biopsy accessible recurrence within one year; an expression of the aggressive nature of the disease. Among patients whose accessible relapse was beyond one year, those with ER- primaries who converted to ER+ had a longer survival than those whose recurrence was classified again as ER- (p = 0.006). This group of patients with ER- primaries who recurred beyond one year with an ER+ tumor in an accessible site represented 29% (40/140) of all patients with ER- primaries and had an estimated overall survival rate of more than 60% at 6 years from the accessible relapse. ER determination upon relapse within one year has very little clinical relevance.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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How to use Chlamydia antibody testing in subfertility patients   总被引:1,自引:9,他引:1  
Screening for tubal factor subfertility by means of Chlamydia antibody testing (CAT) was introduced into the initial work-up of subfertile couples several years ago. The results reported, however, are heterogeneous, and no uniformity exists in cut-off levels of titres, or in definitions of tubal factor subfertility. We performed a prospective cohort study to evaluate the implications of varying the definitions of tubal pathology and of modifying the cut-off levels on the clinical impact of CAT in predicting tubal factor subfertility. In 227 consecutive patients who attended our fertility clinic, the Chlamydia IgG antibody titre was determined and related to tuboperitoneal abnormalities at laparoscopy as a reference standard. According to received operating characteristic (ROC) curve analysis, a titre of 16 is the optimum cut-off level. Increasing the cut-off level improves specificity and positive likelihood ratio (LR+), at the expense of sensitivity and negative LR (LR-). Changing the definition of tubal factor subfertility from unspecified tuboperitoneal abnormalities into extensive adhesions and/or bilateral distal tubal occlusion improves LR+, LR- and kappa significantly. We conclude that CAT is more accurate in predicting severe distal tubal pathology than unspecified tuboperitoneal abnormalities. Although from a statistical point of view a titre of 16 is the optimum cut-off level, from a clinical point of view 32 or 64 may be preferable, depending on the aim of screening and the inception cohort.   相似文献   
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Introduction. Recently, the identification of the SEN virus as a possible etiological agent of parental transmission hepatitis led to the study of the prevalence of such pathogen agents, particularly SENV-H, in our population. This paper compares the rate prevalence in high-risk subjects, such as dialysis patients, and low-risk subjects, such as blood donors. Material and Methods. The study was carried out on SEN virus DNA extracted from serum of dialysis patients and blood donors, and the presence of viral genomes was performed by the nested PCR method. Results. The results showed a higher prevalence in male blood donors, supporting the hypothesis of an epidemiological role for sexual and also parental transmission, as is clearly demonstrated by the high prevalence in dialysis patients. The result reduced the importance of the possible etiological role of the SEN virus due to the high percentage of positivity in healthy population, and it induces one to consider poorly significant the pathogenicity of such viral agents. Conclusion. For this instance, the authors, in agreement with the phylogenically related TT virus, described SEN viruses as absolutely not pathogens and considered them as “simple guests.”  相似文献   
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Although more widespread screening and routine adjuvant therapy has improved the outcome for breast cancer patients in recent years, there remains considerable scope for improving the efficacy, safety and tolerability of adjuvant therapy in the early stage disease and the treatment of advanced disease. Toremifene is a selective estrogen receptor modifier (SERM) that has been widely used for decades in hormone receptor positive breast cancer both in early and late stage disease. Its efficacy has been well established in nine prospective randomized phase III trials compared to tamoxifen involving more than 5500 patients, as well as in several large uncontrolled and non-randomized studies. Although most studies show therapeutic equivalence between the two SERMs, some show an advantage for toremifene. Several meta-analyses have also confirmed that the efficacy of toremifene is at least as good as that of tamoxifen. In terms of safety and tolerability toremifene is broadly similar to tamoxifen although there is some evidence that toremifene is less likely to cause uterine neoplasms, serious vascular events and it has a more positive effect on serum lipids than does tamoxifen. Toremifene is therefore effective and safe in the treatment of breast cancer. It provides not only a useful therapeutic alternative to tamoxifen, but may bring specific benefits.  相似文献   
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Introduction. Implicit memory tasks differ along two orthogonal dimensions, tapping the relative involvement of perceptual/conceptual and identification/production processes. Previous studies have documented a dissociation between perceptual (spared) and conceptual (impaired) implicit memory, using in the latter case a production task (category exemplar generation), in which there is high response competition during the retrieval phase. The present study sought to determine whether the perceptual/conceptual dissociation held when comparing two identification tasks, in which there is no response competition at retrieval.

Methods. In two experiments, repetition priming was assessed in 44 schizophrenic patients and 46 healthy controls in lexical decision (a test based on perceptual identification processes) and category verification (a test based on conceptual identification processes).

Results. Schizophrenic patients achieved a priming as high as that of controls in the lexical decision task. In contrast, only controls exhibited significant priming in the category verification task.

Conclusions. It is concluded that schizophrenia is associated with a specific deficit in conceptual implicit memory, irrespective of the degree of response competition in the test phase.  相似文献   

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Chromosome 1q41‐q42 deletion syndrome is a rare cause of intellectual disability, seizures, dysmorphology, and multiple anomalies. Two genes in the 1q41‐q42 microdeletion, WDR26 and FBXO28, have been implicated in monogenic disease. Patients with WDR26 encephalopathy overlap clinically with those with 1q41‐q42 deletion syndrome, whereas only one patient with FBXO28 encephalopathy has been described. Seizures are a prominent feature of 1q41‐q42 deletion syndrome; therefore, we hypothesized that pathogenic FBXO28 variants cause developmental and epileptic encephalopathies (DEEs). We describe nine new patients with FBXO28 pathogenic variants (four missense, including one recurrent, three nonsense, and one frameshift) and analyze all 10 known cases to delineate the phenotypic spectrum. All patients had epilepsy and 9 of 10 had DEE, including infantile spasms (3) and a progressive myoclonic epilepsy (1). Median age at seizure onset was 22.5 months (range 8 months to 5 years). Nine of 10 patients had intellectual disability, which was profound in six of nine and severe in three of nine. Movement disorders occurred in eight of 10 patients, six of 10 had hypotonia, four of 10 had acquired microcephaly, and five of 10 had dysmorphic features, albeit different to those typically seen in 1q41‐q42 deletion syndrome and WDR26 encephalopathy. We distinguish FBXO28 encephalopathy from both of these disorders with more severe intellectual impairment, drug‐resistant epilepsy, and hyperkinetic movement disorders.  相似文献   
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Regressive morphological lesions, found in peripheral lymphocytes from HIV(+) patients, clearly conflict with normal cycle progression and with the execution of basic housekeeping and immune functions. With these lesions, circulating lymphocytes are destined to spontaneous and energy-independent cell lysis. By means of confocal microscopy and morphometry, we have quantified the rate of circulating T cells that are probably destined to emocatheresis in vivo. This rate includes lymphocytes in which nucleolin fragments have been scattered out of the nuclear region as a result of prelethal alterations in the nuclear membrane permeability. In terms of bioenergetics, these cells show evident anomalies in the energy production machinery that make them unable to carry out ATP-requiring functions. The extent of damaged cell fraction in peripheral blood reflects the frequency with which T lymphocytes leave lymphoid tissue to be cleared in hemocatheretic processes.  相似文献   
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