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1.
BACKGROUND: The aim of the study was to investigate the inhibitory control of an ongoing motor response and to identify underlying neural deficiencies, manifested in event-related potentials, that cause poorer inhibitory performance in children with attention-deficit/hyperactivity disorder. METHODS: A stop-signal paradigm with a primary visual task and auditory stop signal was used to compare performance in 13 children with attention-deficit/hyperactivity disorder and 13 control children, while event-related potentials were recorded simultaneously. RESULTS: Children with attention-deficit/hyperactivity disorder showed poorer inhibitory performance through a slower inhibitory process. Inhibitory processing of auditory stop signals was marked by a frontal N2 component that was reduced in the attention-deficit/hyperactivity disorder group relative to controls. A central positive component (P3) was associated with the success of inhibiting a response, but there were no group differences in its amplitude or latency. CONCLUSIONS: Findings support the hypothesis of deficient inhibitory control in children with attention-deficit/hyperactivity disorder. Slower inhibitory processing appears to be due to a specific neural deficiency that manifests in the processing of the stop signal as attenuated negativity in the N2 latency range.  相似文献   
2.
Molecular mismatch analysis for assessment of histocompatibility in transplantation requires high-resolution HLA typing. Algorithms to “guesstimate” high-resolution from low-resolution typing exist, but their accuracy remains unknown. We converted high-resolution, sequence-based, HLA typing of 310 subjects from an ethnically heterogeneous population to low-resolution equivalents and tested the ability of the NMDP HaploStats and HLA Matchmaker programs to impute/reproduce the measured high-resolution HLA type, using the more common “winner-takes-all” approach. Only 35.6% of the HaploStats imputed HLA-A, -B, -C, -DRB1, and -DQB1 haplotypes had no mistakes, and the accuracy was significantly lower for non-Caucasians (29.1%) compared to Caucasians (45.2%) (odds ratio [OR], 0.5; 95% confidence interval [CI], 0.3-0.8; P = .004). HLA Matchmaker was not able to provide high-resolution haplotypes for 45.2% of Caucasian subjects and 63.5% of non-Caucasian subjects (P = .002). Of those with an imputed result, only 10.3% of Caucasians and 4.8% of non-Caucasians had accurate 10-allele high-resolution output. Eplet analysis revealed additional, inaccurate eplets in 37% of individuals, with 22.5% showing at least 2 additional, inaccurate eplets; incorrect eplets were more common among non-Caucasians (OR, 1.8; 95% CI, 1.1-2.9; P = .018). Given this high error rate, caution should be taken before using imputation tools for clinical or research purposes, especially for non-Caucasian individuals.  相似文献   
3.
PURPOSE: Combining heat with antineoplastic drugs has produced evidence of antitumor synergism. An increasing number of trials are investigating whole body hyperthermia (WBH) in combination with chemotherapy in patients with advanced malignancies. Here we investigated whether the hyperdynamic state of the circulation as a consequence of WBH may stimulate dissemination of malignant cells. EXPERIMENTAL DESIGN: WBH in combination with chemotherapy was administered by a radiant heat device to 20 consecutive patients with advanced epithelial malignancies. One WBH session lasted for approximately 4 h (90 min heating time, 60 min plateau at 41.8 degrees C, and 60-80 min cooling). Peripheral blood was drawn before WBH treatment (baseline), at the end of the plateau (1 h), and 24 h and 48 h thereafter. After removal of leukocytes using anti-CD45 magnetic beads, circulating tumor cells were detected immunocytochemically using the monoclonal antibody A45-B/B3, which binds to a common epitope present on various cytokeratins. RESULTS: The method used to detect tumor cells in the peripheral blood proved to be specific and very sensitive (detection limit 1 tumor cell per 1.7 x 10(5) peripheral blood mononuclear cell). Before WBH, 6 of 20 patients had cyto-keratin-positive cells in their blood. A treatment-induced increase in the number of circulating tumor cells became statistically significant at 24 h after WBH (P = 0.043) and was detected in a total of 9 patients, 5 of whom had no detectable malignant cells at baseline. There was no evidence of a correlation between an increase in the number of circulating tumor cells and increased metastasis frequency. CONCLUSIONS: Our findings suggest that WBH might induce a temporary release of tumor cells into the circulation, but this spread appears to be clinically not significant in patients with advanced malignancies.  相似文献   
4.
5.
Rho kinase plays a key role in the regulation of smooth muscles contraction, including those of the urinary bladder detrusor. Rho kinase pathway modulates the level of phosphorylation of the myosin light chain, mainly through the inhibition of myosin phosphatase. Recent experimental data indicate that its role might be exacerbated in local and systemic pathological conditions which affect the bladder. It seems that Rho kinase inhibitors, such as Y27632, may turn out to be an effective group of drugs in pharmacotheraphy of an overactive bladder (OAB), which will influence the storage phase of the micturition cycle, without interfering with the physiological voiding.  相似文献   
6.
Leptin levels in serum depending on Body Mass Index (BMI) in patients with endometrial hyperplasia and cancer. OBJECTIVES: Concentrations of leptin, a hormone secreted by white adipose tissue, correlate strongly with body mass. Leptin interacts with several other hormones, modifies the activities of some enzymes and proinflammatory cytokines, participates in hematopoiesis, thermogenesis, and angiogenesis, and is involved in the control of carbohydrate and lipid metabolism. This study was undertaken to determine whether serum concentrations of leptin in obese patients with endometrial hyperplasia and cancer deviate from values in patients with normal endometrium. STUDY DESIGN: We enrolled 86 obese postmenopausal women, including 40 with endometrial cancer and hyperplasia and 46 with normal endometrium. Depending on BMI, three subgroups were formed: I<30; II = 30-40; III > 40. Leptin concentrations were measured with immunoenzymatic test kits from IBL. Statistical comparison was done with the chi square (chi(2)) test and Statistica software package. RESULTS: Mean serum concentration of leptin in endometrial cancer and hyperplasia was 16737.1 pg/ml as opposed to 9048.7 pg/ml in patients without endometrial pathology (p<0.0001). Significantly, higher concentrations of leptin were noted in every BMI subgroup of patients with endometrial pathology in comparison to controls (p<0.005). CONCLUSIONS: Leptin appears to participate in proliferative processes of the endometrium. Obesity is an important risk factor in endometrial cancer.  相似文献   
7.
(1) Background: The aim of this study was to assess the concentrations of selected elements in female patients with cancer of the reproductive organs, taking into account the stage of treatment. (2) Methods: The study sample consisted of 51 patients with advanced endometrial cancer and ovarian cancer, undergoing chemotherapy. The median age of the studied patients with endometrial cancer was 66.0 years (IQR: from 60.75 to 70.25), and with ovarian cancer―60.0 years (IQR: from 49.0 to 64.0). Each of the qualified women, after consent to participate in the study, had her blood drawn several times (before surgery, the first course of chemotherapy, the third course of chemotherapy, and the sixth course of chemotherapy) in order to determine serum levels of macro- and micronutrients (Na, Mg, Ca, Zn, P, Cu, Fe, Cd, Ni, and Sr). (3) Results: In the study group of patients with cancer of the reproductive tract, the concentrations of iron (<0.001), magnesium (0.038), sodium (0.014), and nickel (0.037) varied significantly over the course of the study. The analysis showed that the interaction between the stage of chemotherapy and the type of cancer had an effect on the concentrations of magnesium and cadmium (p < 0.05). (4) Conclusions: In the studied group of patients with ovarian and endometrial cancer, the applied chemotherapy significantly changed the concentrations of Fe, Na, and Ni, regardless of the type of tumor. Changes in Mg and Cd concentrations resulted from the interaction between the stage of chemotherapy and the type of cancer. The results of serum concentrations of selected elements in women with cancer of the reproductive organs may help understand the physiological changes resulting from the applied chemotherapy.  相似文献   
8.
Using magnetoencephalography, we investigated the potential of perilesional and contralesional activity to support language recovery in patients with poststroke aphasia. In healthy young controls, left‐lateralized ventral frontotemporal regions responded to semantic anomalies during sentence comprehension and bilateral dorsal frontoparietal regions responded to syntactic anomalies. Older adults showed more extensive bilateral responses to the syntactic anomalies and less lateralized responses to the semantic anomalies, with decreased activation in the left occipital and parietal regions for both semantic and syntactic anomalies. In aphasic participants, we observed compensatory recruitment in the right hemisphere (RH), which varied depending on the type of linguistic information that was processed. For semantic anomalies, aphasic patients activated some preserved left hemisphere regions adjacent to the lesion, as well as homologous parietal and temporal RH areas. Patients also recruited right inferior and dorsolateral frontal cortex that was not activated in the healthy participants. Responses for syntactic anomalies did not reach significance in patients. Correlation analyses indicated that recruitment of homologous temporoparietal RH areas is associated with better semantic performance, whereas higher accuracy on the syntactic task was related to bilateral superior temporoparietal and right frontal activity. The results suggest that better recovery of semantic processing is associated with a shift to ventral brain regions in the RH. In contrast, preservation of syntactic processing is mediated by dorsal areas, bilaterally, although recovery of syntactic processing tends to be poorer than semantic. Hum Brain Mapp 37:2869–2893, 2016. © 2016 Wiley Periodicals, Inc .  相似文献   
9.
Nair KK  Zisman LS  Lader E  Dimova A  Canver CC 《The Annals of thoracic surgery》2003,75(1):282-4; discussion 284-5
Anomalous origin of the left coronary artery from the pulmonary artery is a congenital coronary artery malformation most commonly present in infancy. A variety of surgical procedures have been described to achieve physiological correction of the coronary flow abnormalities. These techniques are effective as long as there is potential for myocardial recovery. However the sequelae of chronic myocardial ischemia that characterize this entity often irreversibly damage the heart and preclude correction and palliation of the native anomaly. In this type of setting, heart transplantation is a realistic option. Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) occasionally presents in adulthood. Anatomic repair with a two coronary artery system may not be optimal in patients presenting with ischemic cardiomyopathy. We report an adult patient with platelet factor 4 (PF4) antibodies who underwent orthotopic heart transplantation (OHT) for ALCAPA.  相似文献   
10.
When polypropylene meshes are used in reconstructive urogynecological surgery, the erosion rates vary from 3.3% to 14% and causative factors for such erosions are still unknown in many cases. Therefore, the aim of our study was to establish the role of immunologic factors in the process of polypropylene tapes erosions after suburethral sling procedures. Serum concentrations of tumor necrosis factor α, interleukin (IL)-2, IL-4, IL-5, IL-10, and interferon (IFN)-γ were estimated in 123 patients suffering from stress urinary incontinence preoperatively and during 12 months follow-up using Human Th1/Th2 Cytokine Cytometric Bead Array I kit. The same immunological assessment was performed in each case of detected tape erosion. Statistical calculation was performed using UNIVARIATE, CORR, and NPAR1WAY procedures from Statistical Analysis System. The unpaired Student’s t test, nonparametric Mann–Whitney U test, and Wilcoxon tests were used. Preoperative IFN-γ concentration was significantly higher in women with subsequent polypropylene mesh erosion when compared to women with successful outcome (p < 0.05). Th1 cytokine profile may be related to the risk of the vaginal erosions following placement of polypropylene meshes. The way to lower erosion rate may involve exclusion of the patients immunologically prone to synthetic material erosion. The factor which can help to select such patients could be preoperative level of IFN-γ.  相似文献   
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