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51.
Abstract: Mammography represents the foundation of breast imaging and maintains the central role in breast imaging techniques applied to breast cancer surveillance. Sonography is best utilized in differentiating solid from cystic mammographic densities. Magnetic resonance imaging is finding utility in sorting out the dense and/or altered breast (augmented breast). Positron emission tomography may be a useful tool to help determine cytotoxic response from therapeutic chemotherapy regimens. Thalium-201 and Technetium-99m Sestamibi show uptake by breast cancer cells and demonstrate a significantly higher specificity than mammography. The higher specificity of scintimammography is feeding current enthusiasm for the study of its role in early detection, complementing mammography in indeterminate lesions and non-invasive axillary staging. A comprehensive review of breast imaging techniques applied to breast cancer surveillance and diagnosis along with management strategies for abnormal studies is provided.  相似文献   
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Lipid components of spermatozoa have an important role in the functional activity of this cell. The protein, apolipoprotein E (apoE), has a central role in lipid transport. The aim of this study was to investigate the distribution of APOE genotypes, ?3?3, ?3?4, and ?2?3, and the corresponding alleles in fertile and infertile males, and to assess the semen parameters from the patients carrying the different alleles. In addition, the levels of cholesterol, phospholipid, and triacylglycerol in spermatozoa, isolated by PureSperm gradient and from seminal plasma in samples from infertile males was compared with respect to the APOE genotype. APOE genotypes were determined by PCR-RFLP on DNA extracted from peripheral blood leucocytes in 108 fertile and 107 infertile men. There was a significant difference between the distribution of APOE genotypes in fertile as compared to infertile males (χ(2)?=?9.1, df?=?2, p?=?0.011). The presence of genotype ?3?4 conferred a 3.82 risk factor for male infertility {Odds ratio?=?3.82 (1.46-10, p?=?0.006)}. Our findings showed that the distribution of APOE genotypes and alleles differed between fertile and infertile individuals and may be a risk factor for male infertility. We suggest that the effects of APOE genotypes may be linked to differences in the efficacy of the expressed apoE isoforms in promoting sperm maturation during epididymal transit.  相似文献   
56.
This study investigated the in vitro production of interferon-gamma, interleukin (IL)-10, IL-12, and IL-13, after antigenic stimulation of the cells (with Leishmania antigen and lipopolysaccharide) using whole blood from patients with cutaneous leishmaniasis lesions caused by Leishmania tropica and in normal volunteers with history of cutaneous leishmaniasis.ELISA results showed that the mean production of interferon-gamma by cells of whole blood in patients with lesions in response to Leishmania antigen was significantly lower than corresponding values in volunteers with history of cutaneous leishmaniasis (P< 0.05) and significantly higher levels of IL-10 production in patients with lesions were observed compared with cured volunteers of the disease (P<0.01). A similar level of IL-12, including p40 subunit of IL-12, was detected in both groups tested in this study in response to stimulation of parasite antigen. The levels of the IL-13 after stimulation with Leishmania antigen were significantly more in patients compared with volunteers with history of cutaneous leishmaniasis (P< 0.01). There was no significant difference in the mean production of IFN-gamma, IL-10, IL-12 and IL-13 by PHA or LPS stimulated cells from patients with lesions and volunteers with history of the disease, indicating that there was no qualitative defect in cytokine production in these patients.In this study, we have detected the decreased production of interferon- gamma by cells of patients with lesions of cutaneous leishmaniasis in response to parasite antigen and unbalanced production of regulatory cytokines such as IL-10 and IL-13 using the whole-blood stimulation assay technique. The required small volume of blood and the rapid set up time are the advantages in this assay technique. Using this assay for further immunodetection of cytokines may confirm its value for clinical investigation.  相似文献   
57.
The neurotransmitter γ-aminobutyric acid (GABA) is involved in the process of memory. It has been reported that the inhibition of GABAB receptors has beneficial effects on cognition. The aim of this study was to investigate the role of CGP35348 (a GABAB receptor antagonist) on dentate gyrus GABAB receptor inhibition and its effects on learning and memory impairments that had been induced in adult male rats by microinjection of β-amyloid (Aβ). Seventy Wistar male rats were randomly divided into seven groups: control, sham (receiving the Aβ vehicle only), Aβ, Aβ + CGP35348 (1, 10, and 100 μg/μL), and CGP35348 alone (10 μg/μL). Memory impairment was induced by unilateral interventricular microinjection of Aβ (6 μg/6 μL). Rats were cannulated bilaterally in the dentate gyrus, and then, they were treated for 20 consecutive days. Learning and memory were assessed using the novel object recognition and passive avoidance learning tests. The discrimination index and the step-through latency were significantly increased in the Aβ + CGP35348 group in comparison to the Aβ only group (P?<?0.05 and P?<?0.01, respectively). Data showed that the discrimination index was decreased in the Aβ + CGP35348 group in comparison with the control group (P?<?0.05) and sham group (P?<?0.01). Moreover, the step-through latency was significantly decreased in the Aβ + CGP35348 group in comparison to the control and sham groups (P?<?0.01). Data from this study indicated that intra-hippocampal microinjection of the GABAB receptor antagonist counteracts the learning, memory, and cognitive impairments induced by Aβ. It can be concluded that the GABAB receptor antagonist is a possible therapeutic agent against the progression of acute Aβ toxicity-induced memory impairment.  相似文献   
58.

Aims

This study was done to assess the risk factors associated with diabetic foot ulcer-free survival in patients with diabetes.

Materials and Methods

Based on a prospective cohort study, ADFC (Ahvaz Diabetic Foot Cohort) study, carried out in a university hospital, all of the patients with diabetes were followed up for new diabetic foot ulcer (DFU). The time of ulcer development was final outcome during two years in the present study. To analyze the data, the variables were first evaluated by univariate analysis. Subsequently variables with P value <0.2 were tested in multivariate analysis, using backward elimination multiple Cox regression.

Results

From among 605 eligible patients of ADFC study, 566 patients without foot ulcer were included for a 2- years follow-up. Thirty subjects (5.3%) developed DFU during the study course none of whom underwent amputation. The DFU-free survival rate was 0.945 over two years of follow-up. In final multivariate Cox regression analysis, the variables which remained in the model and had a statistically significant relationship with time to develop foot ulcer were: dyslipidemia, history of DFU or amputation, nephropathy callus formation in the feet and diabetes duration. Foot deformity and patients' training about self-care of their feet were statistically borderline significant.

Conclusions

The DFU-free survival rate was 0.945 over two years of follow-up. In this study, independent risk factors associated with ulcer-free survival in diabetic foot patients were dyslipidemia, prior history of DFU or amputation, diabetic nephropathy, callus formation in the feet and diabetes duration.  相似文献   
59.
The bone and fat interface is implicated in the pathogenesis of postmenopausal osteoporosis. The association between circulating omentin-1 levels and bone mineral density (BMD) in postmenopausal women has never been assessed. A total of 382 healthy postmenopausal women were randomly selected. Omentin-1, visfatin, adiponectin, the receptor activator of nuclear factor-κB ligand (RANKL), osteoprotegerin, high sensitivity C-reactive protein, degradation products of C-terminal telopeptides of type I collagen, and osteocalcin were measured by highly specific enzyme-linked immunosorbent assay methods. BMD was determined for the lumbar spine (L2-L4) and the proximal femur using dual-energy X-ray absorptiometry. In multivariable-adjusted linear regression, serum omentin-1 levels were inversely correlated with BMD at the lumbar spine (β=-0.11, p=0.020). In multiple regression analyses, serum visfatin and adiponectin levels were not significantly correlated with BMD at different skeletal sites after controlling for age, body mass index, and bone-related markers. However, the highest quartile of adiponectin compared to the lowest quartile, after adjusting for potential confounders, revealed an inverse association with BMD in the lumbar spine (β=-0.19, p=0.010). In conclusion, circulating omentin-1 levels had an inverse correlation with BMD at the lumbar spine in Iranian postmenopausal women. To further understand the role of omentin-1 in bone and mineral metabolism, large-scale longitudinal studies focusing on BMD and osteoporotic fractures are warranted.  相似文献   
60.

Objective

The purpose of this study was to review the literature to determine whether surface electromyography (EMG) is a reliable tool to assess paraspinal muscle fatigue in healthy subjects and in patients with low back pain (LBP).

Methods

A literature search for the period of 2000 to 2012 was performed, using PubMed, ProQuest, Science Direct, EMBASE, OVID, CINAHL, and MEDLINE databases. Electromyography, reliability, median frequency, paraspinal muscle, endurance, low back pain, and muscle fatigue were used as keywords.

Results

The literature search yielded 178 studies using the above keywords. Twelve articles were selected according to the inclusion criteria of the study. In 7 of the 12 studies, the surface EMG was only applied in healthy subjects, and in 5 studies, the reliability of surface EMG was investigated in patients with LBP or a comparison with a control group. In all of these studies, median frequency was shown to be a reliable EMG parameter to assess paraspinal muscles fatigue. There was a wide variation among studies in terms of methodology, surface EMG parameters, electrode location, procedure, and homogeneity of the study population.

Conclusions

The results suggest that there seems to be a convincing body of evidence to support the merit of surface EMG in the assessment of paraspinal muscle fatigue in healthy subject and in patients with LBP.  相似文献   
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