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51.
A prototype multimedia medical database is described for supporting thermal ablation therapy of brain tumors. Its design is motivated by the major need to manage and access multimedia information on the progress and reaction of tumors to various therapy protocols. The database links images to patient data in a way that permits the user to view and query medical information using alphanumeric, temporal, and feature-based predicates. Visualization programs permit the user to view or annotate the query results in various ways. These results support the wide variety of data types and presentation methods required by neuroradiologists to manage thermal ablation therapy data. The database satisfactorily meets the requirements defined by thermal ablation therapy. A similar approach is being undertaken for supporting different therapies of other types of tumors, thus showing the generality of our approach.  相似文献   
52.
The pathophysiological mechanisms underlying binge eating disorder (BED) are poorly understood. There is evidence that abnormalities in brain serotonin (5HT) play an important role in binge eating behavior, therefore genes involved in 5HT transmission, such as the 5HT transporter (5HTT) gene, may contribute to the biological vulnerability to BED. We examined whether the polymorphism of the promoter of the 5HTT gene, consisting of a long (L) and a short (S) variant, was associated with BED. Seventy-seven obese or non-obese women with BED, and 61 normal weight control women were genotyped at the 5HTT gene linked polymorphism (5HTTLPR). Statistical analysis showed that both the LL genotype and the L allele of the 5HTTLPR were significantly more frequent in BED subjects. Moreover, the L allele was associated with a moderate but significant risk to develop BED (OR = 2.01, CI = 1.33-3.57). Although these data should be regarded as preliminary because of the small size of our sample, they suggest that the 5HTTPRL may contribute to the genetic susceptibility to BED.  相似文献   
53.
Major histocompatibility complex (MHC) molecules are of central importance in regulating the immune response against tumors. In this study we used immunohistochemistry to study human leukocyte antigen (HLA) class I and II antigen expression in normal breast tissues and benign, preneoplastic, primary, and metastatic breast lesions using antibodies against beta-2-microglobulin (beta2-m), heavy-chain, and HLA-DR antigens. Whereas all normal tissues and benign lesions were positive for beta2-m and HLA-A, -B, and -C antigens, total loss of HLA class I antigens was found in 37% (11 of 30) of in situ carcinomas, in 43% (56 of 131) of the primary tumors, and in 70% (31 of 45) of the lymph node metastases. HLA-DR was also underexpressed in breast cancer cells; thus 20% (6 of 30) of in situ carcinomas, 15% of invasive carcinomas (20 of 131), and only 1 metastatic case were positive for this antigen. Both HLA class I and II antigen expression were more frequently down-regulated in metastatic lesions than in primary breast lesions (P <0.05), and a tendency toward a simultaneous defective expression of HLA class I and II antigens was observed in primary carcinomas (P = 0.07). However, no correlation was found between the expression of any of the aforementioned molecules and pathological parameters or survival. Interestingly, HLA class I expression was expressed more frequently in tissues with high apoptotic activity and was significantly associated with the expression of the proapoptotic bax gene (P = 0.02), and was inversely associated with expression of the antiapoptotic bcl-2 gene (P = 0.03). We conclude that alterations in HLA class I and II antigen expression are early events in breast carcinogenesis and play significant roles in metastatic progression. In addition, their expression is correlated with apoptosis-regulating proteins, which may influence the cytotoxicity of T cells against HLA class I-specific tumor antigens.  相似文献   
54.
The early outward current in opener muscle fibres of crayfish (Procambarus clarkii) was studied using the two-electrode voltage-clamp technique. This current was abolished in Ca2+-free and 5 mM Cd2+ solutions, and was blocked by extra- or intracellular tetraethylammonium, indicating that it was a Ca2+-dependent K+ current [I K(Ca)]. I K(Ca) was voltage dependent, apamin insensitive and sensitive to charybdotoxin (CTX), which, in addition to its tetraethylammonium sensitivity, suggests that the channels mediating I K(Ca) behave in a BK type manner. I K(Ca) activation was extremely fast, reaching a maximum within 5 ms, and the inactivation was incomplete, stabilizing at a persistent steady-state. I K(Ca) was insensitive to intracellular ethylenebis(oxonitrilo)tetraacetate (EGTA), but was abolished by injection of the faster Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N,N'-tetraacetic acid (BAPTA), suggesting that voltage-dependent Ca2+ channels and those mediating I K(Ca) should be clustered closely on the membrane. Under two-electrode current-clamp recording mode, low amplitude, graded responses were evoked under control conditions, whereas repetitive all-or-none spikes were elicited by application of CTX or after loading the cells with BAPTA. We conclude that I K(Ca) activates extremely quickly, is persistent and is responsible for the generation and control of the low amplitude, graded, active responses of opener muscle fibres.  相似文献   
55.
Increased antiphospholipid antibody prevalence has been demonstrated by a number of recent studies in in-vitro fertilization (IVF) patients but the potential effects of antiphospholipid antibodies on the different components of the reproductive process and the consideration of whether to test IVF patients for antiphospholipid antibodies are controversial. The present study was undertaken to investigate the possible association between the presence of circulating antiphospholipid antibodies (namely the lupus anticoagulant and anticardiolipin antibodies), among a series of 21 consecutive IVF patients having a clinical spontaneous abortion after their first embryo transfer. As a control group (n=42), the nearest IVF cycle resulting in an ongoing pregnancy before and after each miscarried IVF cycle (i.e. the closest cycles in temporal relationship to the index cycle) was used. One patient (4.8%) in the study group and two women (4.8%) among controls were seropositive for antiphospholipid antibodies. These low and similar seropositivity rates found in the two groups studied lead us to conclude that antiphospholipid antibodies testing in IVF patients should be considered only in those women having repeated failures of implantation/clinical abortion after embryo transfer but not in an infertile general population reaching an IVF programme.   相似文献   
56.
Immunopathophysiological mechanisms in endometriosis-associated reproductive failure were studied in appropriate populations: infertile and fertile women with and without endometriosis. The incidence of sera positive for any of the autoantibodies tested among infertile women with endometriosis (n = 25) was similar to that observed in the three control groups [unexplained infertility patients (n = 25) and fertile women with (n = 10) and without (n = 25) endometriosis]. The mean volume of peritoneal fluid was significantly elevated in women with endometriosis (both fertile and infertile) as compared with patients without endometriosis (fertile or infertile). The concentration of peritoneal fluid leukocytes and the percentage of cells positive for macrophage markers were significantly increased and the percentage of T lymphocytes significantly decreased in infertile women with endometriosis but not in patients with unexplained infertility and fertile women with endometriosis, as compared with fertile controls without endometriosis. Macrophages from infertile patients with endometriosis had higher sperm phagocytosis than did those from infertile women without endometriosis or fertile subjects with or without endometriosis. Incidences of serum and peritoneal fluid samples embryotoxic to the in-vitro development of 2-cell mouse embryos were significantly higher in infertile patients with endometriosis than in unexplained infertility patients and fertile women with or without endometriosis. It is concluded that immunological mechanisms of endometriosis-associated infertility exist but that these peritoneal immunological factors in infertile women with endometriosis are related to their subfertility rather than to the presence of ectopic endometrial implants. This is supported by the lack of immunological abnormalities observed among fertile women with endometriosis. These immunological abnormalities are lacking in patients with unexplained infertility.   相似文献   
57.
We aimed to report the implementation of a phenylketonuria (PKU) transition program and study the effects of follow-up with an adult team on metabolic control, adherence, and loss of follow-up. Fifty-five PKU patients were analysed in the study periods (SP): 2 years before (SP1) and after the beginning of adult care (SP2). Retrospective data on metabolic control and number of clinic appointments were collected for each SP, and protein intakes were analysed. In SP2, three patients (6%) were lost to follow-up. There was a small but statistically significant increase in median number of annual blood spots from SP1 to SP2: 11 (7–15) vs. 14 (7–20); p = 0.002. Mean ± SD of median blood Phe remained stable (525 ± 248 µmol/L vs. 552 ± 225 µmol/L; p = 0.100); median % of blood Phe < 480 µmol/L decreased (51 (4–96)% vs. 37 (5–85)%; p = 0.041) and median number of clinic appointments increased from SP1 to SP2: (5 (4–6) vs. 11 (8–13); p < 0.001). No significant differences were found regarding any parameter of protein intake. Our results suggest that the implementation of an adult service was successful as impact on metabolic control was limited and attendance remained high. Continuous dietetic care likely contributed to these results by keeping patients in follow-up and committed to treatment.  相似文献   
58.
Background: The prevention and treatment of obesity and its cardio-metabolic complications are relevant issues worldwide. Among lifestyle approaches, very low-calorie ketogenic diets (VLCKD) have been shown to lead to rapid initial weight loss, resulting in better long-term weight loss maintenance. As no information on VLCKD studies carried on in a real-world setting are available, we conducted this multi-centre study in a real-world setting, aiming at assessing the efficacy and the safety of a specific multiphasic VLCKD program in women with overweight or obesity. Methods: A multi-center, prospective, uncontrolled trial was conducted in 33 outpatient women (age range 27–60 y) with overweight or obesity (BMI: 30.9 ± 2.7 kg/m2; waist circumference: 96.0 ± 9.4 cm) who started a VLCKD dietary program (duration: 24 weeks), divided into four phases. The efficacy of VLCKD was assessed by evaluating anthropometric measures and cardiometabolic markers; liver and kidney function biomarkers were assessed as safety parameters. Results: The VLCKD program resulted in a significant decrease of body weight and BMI (−14.6%) and waist circumference (−12.4%). At the end of the protocol, 33.3% of the participants reached a normal weight and the subjects in the obesity range were reduced from 70% to 16.7%. HOMA-IR was markedly reduced from 3.17 ± 2.67 to 1.73 ± 1.23 already after phase 2 and was unchanged thereafter. Systolic blood pressure decreased after phase 1 (−3.5 mmHg) and remained unchanged until the end of the program. Total and LDL cholesterol and triglycerides were significantly reduced by VLCKD along with a significant HDL cholesterol increase. Liver, kidney and thyroid function markers did not change and remained within the reference range. Conclusions: The findings of a multi-center VLCKD program conducted in a real-world setting in a cohort of overweight/obese women indicate that it is safe and effective, as it results in a major improvement of cardiometabolic parameters, thus leading to benefits that span well beyond the mere body weight/adiposity reduction.  相似文献   
59.
The use of ultrasound as a clinical diagnostic tool and guide of bedside procedures has become an indispensable examination in the acute critically ill patient. The training of professionals in minimum skills of knowledge, management and indications of use of ultrasound required to be defined by the Scientific Societies. The Intensive Care Ultrasound Working Group of the Spanish Society of Anesthesiology and Resuscitation (SEDAR), of the Spanish Society of Internal Medicine (SEMI) and the Spanish Society of Emergency Medicine (SEMES) has developed this consensus document in which the recommended training program and the minimum competencies to be achieved with regard to the use of Ultrasound in Intensive Care, Anesthesia and Emergency medicine are defined.This document defines the training program and the skills to acquire in order to achieve the diploma in lung, abdominal and vascular ultrasound. This document can serve as a guide to define the skills to be acquired in the training programs of residents (MIRs) of specialists working in intensive care, anesthesia, and emergency medicine.  相似文献   
60.
Dual-energy X-ray absorptiometry (DXA)-derived appendicular lean mass/height2 (ALM/ht2) is the most commonly used estimate of muscle mass in the assessment of sarcopenia, but its predictive value for fracture is substantially attenuated by femoral neck (fn) bone mineral density (BMD). We investigated predictive value of 11 sarcopenia definitions for incident fracture, independent of fnBMD, fracture risk assessment tool (FRAX®) probability, and prior falls, using an extension of Poisson regression in US, Sweden, and Hong Kong Osteoporois Fractures in Men Study (MrOS) cohorts. Definitions tested were those of Baumgartner and Delmonico (ALM/ht2 only), Morley, the International Working Group on Sarcopenia, European Working Group on Sarcopenia in Older People (EWGSOP1 and 2), Asian Working Group on Sarcopenia, Foundation for the National Institutes of Health (FNIH) 1 and 2 (using ALM/body mass index [BMI], incorporating muscle strength and/or physical performance measures plus ALM/ht2), and Sarcopenia Definitions and Outcomes Consortium (gait speed and grip strength). Associations were adjusted for age and time since baseline and reported as hazard ratio (HR) for first incident fracture, here major osteoporotic fracture (MOF; clinical vertebral, hip, distal forearm, proximal humerus). Further analyses adjusted additionally for FRAX-MOF probability (n = 7531; calculated ± fnBMD), prior falls (y/n), or fnBMD T-score. Results were synthesized by meta-analysis. In 5660 men in USA, 2764 Sweden and 1987 Hong Kong (mean ages 73.5, 75.4, and 72.4 years, respectively), sarcopenia prevalence ranged from 0.5% to 35%. Sarcopenia status, by all definitions except those of FNIH, was associated with incident MOF (HR = 1.39 to 2.07). Associations were robust to adjustment for prior falls or FRAX probability (without fnBMD); adjustment for fnBMD T-score attenuated associations. EWGSOP2 severe sarcopenia (incorporating chair stand time, gait speed, and grip strength plus ALM) was most predictive, albeit at low prevalence, and appeared only modestly influenced by inclusion of fnBMD. In conclusion, the predictive value for fracture of sarcopenia definitions based on ALM is reduced by adjustment for fnBMD but strengthened by additional inclusion of physical performance measures. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
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