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151.
网络的应用为人们带来了巨大的方便。生物材料网络 (Biomat.net)于 2 0 0 0年 2月在线了。使用者可以免费注册 ,成为Biomat.net会员 ,利用该网站进行互动的信息交流。Biomat.net选择性地连接了一些生物材料和相关的生物医学工程、生物学、医药和健康网址。Biomat.net网站希望成为连接、查询全世界生物材料信息的主要工具。它是非盈利性质的。Biomat.net的主要目标是 :(1 )为科学家、研究者、商业团体、政府和学术界提供有组织和有意义的生物材料信息资源 ;(2 )成为生物材料领域的网络资源、组…  相似文献   
152.
Baby-stealing is probably one of the more taboo crimes in our society. Its connection with psychological distress, while generally acknowledged, is not always well understood. In this paper we present an unusual and complex case of a woman who attempted to steal young babies while in a state of extreme psychological distress following epileptic seizures. While the post-epileptic state was characterized as 'psychotic' there were clear psychological antecedents to explain the form in which the postical psychosis was expressed. Treatment strategies included modification of medication regime and use of cognitive therapy to ameliorate the impact of postictal confusion.  相似文献   
153.
154.
Background. Seven patients with the diagnosis of Ebstein’s malformation of the tricuspid valve were operated on. Mean age was 12 years (range, 7 to 16 years). All were cyanotic, with severe tricuspid regurgitation. Thromboembolism was not present. No associated cardiac malformations were present.

Methods. Surgical repair included tricuspid annuloplasty associated with longitudinal plication of the atrialized portion of the right ventricle. This was attained by approximating the anterior-posterior commissure with either the posterior-septal commissure or the septal leaflet remnant. The thin atrialized ventricular wall thus excluded remained as a cul du sac and was plicated by suturing along the longitudinal axis of the heart. When present, the dysplastic posterior leaflet was included in the plication. In essence, a monocuspid right atrioventricular valve was fashioned out of the anterior leaflet. The remaining septal leaflet played a minimal functional role. No additional procedures for treatment of arrhythmia were associated with the technique described.

Results. The postoperative course was uneventful in all patients. Mean follow-up is 4.3 years (range, 1 to 10 years). Doppler echocardiographic studies reveal satisfactory monocusp valve function in all patients, with adequate coaptation of the anterior leaflet and the septal structures.

Conclusions. This technique seems applicable to most forms of Ebstein’s malformation and is reproducible. The technique relies on the adequate mobilization of the anterior leaflet. Occasionally it is necessary to free fibrous adhesions of the leaflet to the underlying ventricular surface.  相似文献   

155.
GST profiling may be useful in the screening for thyroid nodule malignancy   总被引:2,自引:0,他引:2  
The modifying effects of dietary feeding of atrazine, which is one of the endocrine disrupting chemicals (EDCs), on 7,12-dimethylbenz(a)anthracene (DMBA)-induced ovarian carcinogenesis were investigated in female Sprague-Dawley rats. We also assessed the effect of atrazine on proliferating cell nuclear antigen (PCNA)-index and the expression of estrogen receptor (ER)- and -β and androgen receptor (AR) in induced neoplasms. Rats were given a single injection of DMBA (0.01 ml of 0.5% DMBA suspended in olive oil) into their left ovary to induce ovarian neoplasms. They also received the experimental diet containing 5, 50 or 500 ppm atrazine for 50 weeks, starting one week after the dosing of DMBA. The diets used were free of soy products. DMBA exposure produced left ovarian adenocarcinoma with an incidence of 45% at the end of the study (week 51). Dietary administration atrazine reduced the incidence of ovarian adenocarcinoma: 22, 28, and 26% incidences in rats fed 5, 50, and 500 ppm atrazine containing diets after DMBA exposure, respectively, without statistical significance among the groups. The PCNA-index in adenocarcinomas was greater than that of surface ovarian epithelium. ER-, β and AR were expressed in a variable percentage of moderately and poorly differentiated adenocarcinoma cell nuclei, but their reactivity was extremely weak or negative in well differentiated adenocarcinoma cells. These results might suggest dietary feeding of a EDC atrazine did not affect DMBA-induced rat ovarian carcinogenesis.  相似文献   
156.
Heat shock proteins (Hsp) are moving from the category of basically intracellular chaperone molecules to important proteins in both innate and acquired immune responses, with great potential for clinical application as immunomodulators. Both proinflammatory and regulatory Hsp-reactive T cells have been described in animal models of autoimmune diseases. To investigate the role of autoreactivity to Hsp60 and Hsp70 in human transplantation, we analyzed, sequentially, peripheral blood mononuclear cell proliferation and cytokine production before and at different time points after renal transplantation, as well as the modulation of proliferation to Hsp in the presence of exogenous cytokines. Proliferation to Hsp60 and Hsp70 in the pretransplantation (pre-Tx) period was significantly associated with rejection episodes in the first months post-Tx. In contrast, IL-4 production was significantly associated with absence of rejection. Addition of exogenous IL-4 distinctly modulated the proliferative response to Hsp60; inhibiting proliferation in 83% of patients in the early post-Tx period (0-6 months), in which rejection episodes occurred, and inducing proliferation in 62.5% of patients in the later period (>12-24 months), when no rejection was observed. Characterization of autoreactive anti-Hsp60 regulatory T cells may permit new approaches to control the proinflammatory response to the graft, as well as aggressive autoimmunity.  相似文献   
157.
A decreased radioiodine uptake is frequently detected in differentiated thyroid carcinomas (DTC) and is associated with high recurrence rate and reduced survival. We investigated the correlation between NIS mRNA expression levels in the primary tumor and patient outcome using a quantitative real-time RT-PCR method. NIS expression was decreased in 17 DTC (21.04+/-39.66 pg Eq) compared to four autoimmune thyroid disease (180.51+/-92.63 pg Eq) and 14 normal tissues (75.71+/-66.98 pg Eq) (p<0.0001). The 17 thyroid differentiated carcinoma patients were submitted to surgery complemented by radioiodine ablation and had at least 24 months of follow-up, under levothyroxine continued suppressive therapy. According to their outcome, we could characterize a group of papillary carcinoma patients with aggressive carcinomas, whose NIS mRNA levels were markedly lower than a group with non-aggressive carcinomas (0.62+/-0.79 versus 54.87+/-53.79; p<0.005). We suggest that the quantification of NIS mRNA relative levels in the primary tumor may predict poor outcome.  相似文献   
158.
159.
To reduce obesity and thus promote healthy food choices, front-of-pack (FOP) labels have been introduced. Though FOP labels help identify healthy foods, their impact on actual food choices is rather small. A newly developed so-called swipe task was used to investigate whether the type of label used (summary vs. nutrient-specific) had differential effects on different operationalizations of the “healthier choice” measure (e.g., calories and sugar). After learning about the product offerings of a small online store, observers (N = 354) could, by means of a swipe gesture, purchase the products they needed for a weekend with six people. Observers were randomly assigned to one of five conditions, two summary label conditions (Nutri-Score and HFL), two nutrient (sugar)-specific label conditions (manga and comic), or a control condition without a label. Unexpectedly, more products (+7.3 products)—albeit mostly healthy ones—and thus more calories (+1732 kcal) were purchased in the label conditions than in the control condition. Furthermore, the tested labels had different effects with respect to the different operationalizations (e.g., manga reduced sugar purchase). We argue that the additional green-labeled healthy products purchased (in label conditions) “compensate” for the purchase of red-labeled unhealthy products (see averaging bias and licensing effect).  相似文献   
160.
Accurate typing of HLA-A antigens and analysis of serological deficiencies   总被引:5,自引:0,他引:5  
We are reporting the results of HLA-A typing by PCR-SSOP complemented by PCR-SSP of samples obtained from the National Marrow Donor Program (NMDP). These samples were a representative group from 2486 tested in duplicate by serology. A total of 390 samples gave HLA-A discrepant results. Comparing the molecular typing results of 238 samples (samples with available DNA) with the serological typing results, 54 homozygotes and 184 heterozygotes produced a total of 422 assignments by molecular methods. We found assignment discrepancies in 147/422 (35%) in laboratory 1 and 144/422 (34%) in laboratory 2 (a combined group of 4 NMDP laboratories; laboratory 1 is not included). The serological discrepancies found were of 3 categories: a) false negatives, b) incomplete typing (discrepancies due to the level of resolution within a cross-reactive or CREG group) and c) false positives. Major problems were identified using serology for typing HLA-A antigens: a) inability to identify all WHO-recognized specificities, more frequently in non-Caucasians or in HLA-A specificities known to be found more frequently in non-Caucasians for laboratory 1 and incorrect assignments of A19 specificities in laboratory 2, b) incorrect assignments in cells with poor viability and c) false-positive assignments in homozygotes. We propose a possible strategy to type HLA-A specificities with two steps: a) a minimum of serology for typing specificities for common CREG groups: A1, A2, A3, A11, A9, A10, A28, A19. However, a given laboratory can determine the level of serological assignments needed as a first step. And b) molecular methods to identify splits: A23, A24, A29, A30, A31, A32, A33, A34, A36, A66, A74 and A80. The technique described is useful for large-scale bone marrow donor typings for cells with poor viability, and for resolving ambiguous results including false-positive assignments of homozygous cells.  相似文献   
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