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61.
Plasmacytoma of the breast is a rare condition that may occur as a solitary finding or in association with multiple myeloma. Of the cases of plasmacytoma of the breast that have been described, nearly half have been bilateral. We report a case of bilateral plasmacytoma of the breast detected on a routine screening mammogram in a patient with a recent diagnosis of multiple myeloma.  相似文献   
62.
Calcification is the most common cause of damage and subsequent failure of heart valves. Although it is a common phenomenon, little is known about it, and less about the inorganic phase obtained from this type of calcification. This article describes the scanning electron microscopy (SEM)/energy dispersive X‐ray spectroscopy and Ca K‐edge X‐ray absorption near edge structure (XANES) characterization performed in natural and bioprosthetic heart valves calcified in vivo (in comparison to in vitro‐calcified valves). SEM micrographs indicated the presence of deposits of similar morphology, and XANES results indicate, at a molecular level, that the calcification mechanism of both types of valves are probably similar, resulting in formation of poorly crystalline hydroxyapatite deposits, with Ca/P ratios that increase with time, depending on the maturation state. These findings may contribute to the search for long‐term efficient anticalcification treatments.  相似文献   
63.
Background: Loss of consciousness (LOC) and immobility to surgical incision seem to be mediated at different levels of the central nervous system. Pharmacologic studies of hypnotic agents have previously focused on combinations of either volatile or intravenous anesthetics. This study examined the combination of inhaled sevoflurane and intravenous propofol at these two clinically relevant anesthetic end points.

Methods: Thirty-six elective surgical patients were initially enrolled. Conditions approximating steady state were obtained for sevoflurane and target-controlled propofol infusions. Patients were sequentially evaluated for LOC (loud voice plus mild prodding) and immobility to surgical incision. The study was designed using the Dixon up-down method.

Results: The observed propofol effect target with 50% response plus sevoflurane (0.46% end-tidal concentration) was 1.2 [mu]g/ml (95% confidence interval, 1.1-1.3 [mu]g/ml). It was not significantly different from that predicted (1.5 [mu]g/ml; 95% confidence interval, 1.2-1.7 [mu]g/ml) by simple additivity. The effective plasma concentration of propofol that suppressed movement to skin incision in 50% of patients was 5.4 [mu]g/ml (95% confidence interval, 4.8-6.0 [mu]g/ml) plus sevoflurane (0.86%) and was not significantly different from that predicted by additivity (5.4 [mu]g/ml; 95% confidence interval, 4.8-5.9 [mu]g/ml). Both analyses had adequate power (90%) to detect a significant change (+/-19 to 25%) from predicted value. Repeated-measures analysis of variance identified a Bispectral Index value of 70 as the break point between those who responded at LOC or did not.  相似文献   

64.
Acute myeloid leukemia (AML) with multilineage dysplasia was introduced in the 2001 World Health Organization (WHO) classification to encompass cases of AML characterized by myelodysplastic syndrome–like features. The 2008 WHO classification revised this group into a new category, AML with myelodysplasia-related changes (AML-MRC). The category now includes patients with at least 20% blasts in peripheral blood or bone marrow and any of the following: (1) AML arising from a previous MDS or mixed MDS/myeloproliferative neoplasm, (2) AML with a specific MDS-associated cytogenetic abnormality and/or (3) AML with multilineage dysplasia. Up to 48% of all patients with AML are encompassed within the AML-MRC subgroup. AML-MRC patients have worse prognosis compared with patients with AML, not otherwise specified.  相似文献   
65.
66.
OBJECT: Oligodendrogliomas are rare primary brain tumors. They comprise approximately 5 to 33% of all glial tumors but differ from astrocytomas by being associated with a more favorable prognosis, making their correct identification important. Allelic loss of chromosome arms 1p and 19q is found in a substantial subpopulation of tumors with an oligodendroglioma phenotype. Anaplastic oligodendrogliomas with allelic loss of 1p have been associated with chemosensitivity and a longer patient survival period. METHODS: Oligodendroglial neoplasms were studied using fluorescence in situ hybridization of formalin-fixed, paraffin-embedded tissue specimens; reference and target probe sets were used to map the telomeric regions of 1p and 19q. The results were correlated with the clinical characteristics of patients treated at our institution between 1993 and 2003. Data obtained in 96 patients were analyzed. This included 63 patients (65.6%) with World Health Organization (WHO) Grade II oligodendroglioma, 22 (23%) with Grade III oligodendroglioma, and 11 (11.4%) with mixed oligoastrocytoma. Analysis of 1p in patients with pure oligodendroglioma revealed a loss of 1p in 42 patients (49.4%). In 46 of these patients 19q was lost and in 70 (82.3%) there was concordance for combined loss or retention of both 1p and 19q (p < 0.0001). Patients with oligodendroglioma in whom a loss of 1p was present fared significantly better, and this outcome was unrelated to the treatment modality or WHO grade, compared with patients in whom 1p was intact (p < 0.05). CONCLUSIONS: To the authors' knowledge, this study includes the largest published series of WHO Grade II oligodendroglioma and 1p analysis. The results suggest that the association between long-term survival and 1p loss in oligodendroglioma is unrelated to treatment. The authors of further prospective studies may better determine the true value of the allelic loss of 1p and its implication for clinical decision making.  相似文献   
67.
AIM: To examine the association of genetic polymorphisms (-308)G/A TNFα, (+250)A/G Ltα, (+36)A/G TNFR1, (+1663)A/G TNFR2 with the development of primary open angle glaucoma (POAG) among people in Central Russia. METHODS: The study sample included 443 individuals, of which 252 patients with POAG and 191 individuals in the control group. Genotyping of (-308)G/A TNFα, (+250)A/G Ltα, (+36)A/G TNFR1, (+1663)A/G TNFR2 was performed using polymerase chain reaction. The distribution of alleles and genotypes of the studied DNA markers in the groups was examined by 2×2 contingency tables and χ2 with the Yates’s correction for continuity and odds ratios (OR) with 95% confidence intervals (CI). RESULTS: Allele (-308)G TNFα (Р=0.01, OR=1.78, 95%CI 1.12-2.85) was identified as a risk factor for POAG. Homozygotes (-308) AA TNFα are at a lowest risk for development of the disease (Р=0.01, OR=0.0005). The following combination of genetic variants of cytokines were associated with a reduced risk of POAG: (+1663)A TNFR2 and (+250)G Ltα (OR=0.34) CONCLUSION: Genetic polymorphisms (-308)G/A TNFα, (+250)A/G Ltα, (+1663)A/G TNFR2 associated with the development of POAG in the population of Central Russia.  相似文献   
68.
Objective

To determine frequencies, interlaboratory reproducibility, clinical ratings, and prognostic implications of neural antibodies in a routine laboratory setting in patients with suspected neuropsychiatric autoimmune conditions.

Methods

Earliest available samples from 10,919 patients were tested for a broad panel of neural antibodies. Sera that reacted with leucine-rich glioma-inactivated protein 1 (LGI1), contactin-associated protein-2 (CASPR2), or the voltage-gated potassium channel (VGKC) complex were retested for LGI1 and CASPR2 antibodies by another laboratory. Physicians in charge of patients with positive antibody results retrospectively reported on clinical, treatment, and outcome parameters.

Results

Positive results were obtained for 576 patients (5.3%). Median disease duration was 6 months (interquartile range 0.6–46 months). In most patients, antibodies were detected both in CSF and serum. However, in 16 (28%) patients with N-methyl-d-aspartate receptor (NMDAR) antibodies, this diagnosis could be made only in cerebrospinal fluid (CSF). The two laboratories agreed largely on LGI1 and CASPR2 antibody diagnoses (κ = 0.95). The clinicians (413 responses, 71.7%) rated two-thirds of the antibody-positive patients as autoimmune. Antibodies against the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR), NMDAR (CSF or high serum titer), γ-aminobutyric acid-B receptor (GABABR), and LGI1 had ≥ 90% positive ratings, whereas antibodies against the glycine receptor, VGKC complex, or otherwise unspecified neuropil had ≤ 40% positive ratings. Of the patients with surface antibodies, 64% improved after ≥ 3 months, mostly with ≥ 1 immunotherapy intervention.

Conclusions

This novel approach starting from routine diagnostics in a dedicated laboratory provides reliable and useful results with therapeutic implications. Counseling should consider clinical presentation, demographic features, and antibody titers of the individual patient.

  相似文献   
69.
BACKGROUND: There is substantial but not conclusive evidence that insulin resistance is related to left ventricular mass (LVM) in hypertensive individuals. To what extent this association is mediated by the relationship between plasma insulin and body size and build is still debated, and is poorly explored in nonhypertensive people. OBJECTIVE: To explore the relationship between insulin or insulin resistance and LVM in a population-based sample of nonhypertensive participants of the Gubbio Study. METHOD: Echocardiographic LVM was determined in 91 nondiabetic, nonhypertensive individuals aged 45-54 years, participating in a population-based screening. LVM normalized for height2.7 was used in the analyses; LV hypertrophy was defined as a value of > or = 50 g/m2.7 in men or > or = 47 g/m2.7 in women. Fasting plasma insulin and glucose were measured and the Homeostasis Model Assessment (HOMA) index was used as a measure of insulin resistance. RESULTS: LVM was positively and significantly correlated with body mass index (BMI) (P < 0.01), waist circumference (P < 0.01) and HOMA index (P < 0.05), whereas correlations with plasma glucose and triglycerides did not reach statistical significance (P = 0.07 for both); all correlations were offset after adjusting for BMI. Fasting plasma insulin and HOMA index were not significantly different in subjects with or without LV hypertrophy (70.8 +/- 27.8 vs. 77.7 +/- 29.6 pmol/l and 2.2 +/- 1.0 vs. 2.6 +/- 1.4, respectively). Bivariate analysis performed stratifying participants above or below the 75th percentile of the sex-specific distribution for BMI (29.1 and 29.4 kg/m2 for males and females, respectively) and plasma insulin (84 pmol/l for either gender), did not result in appreciable differences in LVM due to insulin levels. Similar results were obtained replacing the HOMA index for insulin in the analysis. CONCLUSION: In nonhypertensive individuals left ventricular mass is not associated with plasma insulin independently of body mass index.  相似文献   
70.
Caffeine is an efficient inhibitor of cellular DNA repair, likely through its effects on ATM (ataxia telangiectasia mutated) and ATR (ATM and Rad3-related) kinases. Here, we show that caffeine treatment causes a dose-dependent reduction in the total amount of HIV-1 and avian sarcoma virus retroviral vector DNA that is joined to host DNA in the population of infected cells and also in the number of transduced cells. These changes were observed at caffeine concentrations that had little or no effect on overall cell growth, synthesis, and nuclear import of the viral DNA, or the activities of the viral integrase in vitro. Substantial reductions in the amount of host-viral-joined DNA in the infected population, and in the number of transductants, were also observed in the presence of a dominant-negative form of the ATR protein, ATRkd. After infection, a significant fraction of these cells undergoes cell death. In contrast, retroviral transduction is not impeded in ATM-deficient cells, and addition of caffeine leads to the same reduction that was observed in ATM-proficient cells. These results suggest that activity of the ATR kinase, but not the ATM kinase, is required for successful completion of the viral DNA integration process and/or survival of transduced cells. Components of the cellular DNA damage repair response may represent potential targets for antiretroviral drug development.  相似文献   
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