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41.
Background The role of the single nucleotide polymorphisms (SNPs) on positions 2677G>T/A and 3435C>T of the multi-drug-resistance gene 1 (MDR1) in inflammatory bowel disease (IBD) remains unclear. Aims To further elucidate the potential impact of MDR1 two-locus genotypes on susceptibility to IBD and disease behaviour. Patients and methods Three hundred eighty-eight German IBD patients [244 with Crohn’s disease (CD), 144 with ulcerative colitis (UC)] and 1,005 German healthy controls were genotyped for the two MDR1 SNPs on positions 2677G>T/A and 3435C>T. Genotype–phenotype analysis was performed with respect to disease susceptibility stratified by age at diagnosis as well as disease localisation and behaviour. Results Genotype distribution did not differ between all UC or CD patients and controls. Between UC and CD patients, however, we observed a trend of different distribution of the combined genotypes derived from SNPs 2677 and 3435 (χ2 = 15.997, df = 8, p = 0.054). In subgroup analysis, genotype frequencies between UC patients with early onset of disease and controls showed significant difference for combined positions 2677 and 3435 (χ2 = 16.054, df = 8, p = 0.034 for age at diagnosis ≥25, lower quartile). Herein the rare genotype 2677GG/3435TT was more frequently observed (odds ratio = 7.0, 95% confidence interval 2.5 – 19.7). In this group severe course of disease behaviour depended on the combined MDR1 SNPs (χ2 = 16.101, df = 6, p = 0.017 for age at diagnosis ≥25). No association of MDR1 genotypes with disease subgroups in CD was observed. Conclusions While overall genotype distribution did not differ, combined MDR1 genotypes derived from positions 2677 and 3435 are possibly associated with young age onset of UC and severe course of disease in this patient group.  相似文献   
42.
No other previously published studies consider the relative motion of orthotic components positioned on the upper arm and the forearm. This study therefore measured the location and direction of the axis of rotation of an orthotic component fixed to the forearm in relation to an orthotic component fixed to the upper arm, and compared the results with those obtained by palpation. A plane flexion or extension motion of the forearm component in relation to the component on the upper arm can be described as a pure rotation about a fixed centre. However, activation of the biceps or triceps shifts that centre by around 2 cm, due to a displacement of the humerus within the orthotic component on the upper arm. Within a range of approximately 1 cm, the location of the axis of rotation was similar to that obtained by palpation. Neither custom-made plastic/foam orthoses with their hinges aligned to the measured axis, nor orthoses with their hinges aligned to the palpated axis, exhibited any difference in the wearer's comfort. It is concluded that the best choice for the location of the axis of a hinge-type orthosis for the elbow constitutes a compromise between the axes for active flexion and active extension. In view of the large influence that muscle activation has on axis location, errors in the order of 1 cm seem to be negligible when adjusting the hinge of an orthosis in individual cases.  相似文献   
43.
不同补锌方法对儿童免疫功能的影响   总被引:2,自引:0,他引:2  
研究不同补锌方法(补锌,补充微量营养素,补充锌加微量营养素)改善缺锌儿童免疫功能的作用,结果显示:实验10wk后,三个实验组缺锌儿童血清锌浓度明显升高,同时淋巴细胞刺激指数明显高于对照组,流式细胞仪检测细胞周期显示对照组G0/G1期细胞增多,而实验组S+G0/G1期细胞增多,细胞处于增殖活化状态。三组中又以锌+微量营养素作用效果最好。表明:锌和微量营养素单独使用均增强缺锌儿童的免疫功能,但锌和微量  相似文献   
44.
Objective. To predict clinical outcome after ankle sprains on the basis of magnetic resonance (MR) findings. Design and patients. Twenty-nine consecutive patients (mean age 32.9 years, range 13–60 years) were examined clinically and with MR imaging both after trauma and following standardized conservative therapy. Various MR abnormalities were related to a clinical outcome score. Results. There was a tendency for a better clinical outcome in partial, rather than complete, tears of the anterior talofibular ligament and when there was no fluid within the peroneal tendon sheath at the initial MR examination (P=0.092 for either abnormality). A number of other MR features did not significantly influence clinical outcome, including the presence of a calcaneofibular ligament lesion and a bone bruise of the talar dome. Conclusion. Clinical outcome after ankle sprain cannot consistently be predicted by MR imaging, although MR imaging may be more accurate when the anterior talofibular ligament is only partially torn and there are no signs of injury to the peroneal tendon sheath.  相似文献   
45.
A 36 year-old infertile female developed a stage IV (FIGO) ovarian carcinoma consisting of a poorly differentiated Sertoli-Leydig cell tumour after receiving one course of ovulation induction with follicle stimulating hormone (FSH), human menopausal gonadotrophin (HMG) and human chorionic gonadotrophin (HCG) followed by gonadotrophin-releasing hormone analogue (GnRHa). The patient died of liver metastasis and hepatic failure 4 1/2 months after first diagnosis, despite aggressive treatment consisting of debulking surgery and aggressive adjuvant chemotherapy.   相似文献   
46.

BACKGROUND:

Psychosocial stress can be the cause or the consequence of hypertension.

OBJECTIVE:

To study the association between hypertension and anxiety or depression in adults from Hong Kong, China.

SUBJECTS AND METHODS:

Patients with diagnosed hypertension (n=197) were recruited to complete the Hospital Anxiety and Depression Scale (HADS) questionnaire. The control group comprised 182 normotensive subjects recruited using random telephone numbers.

RESULTS:

The score in the anxiety subscale (HADS-A) of the HADS correlated with age (r= −0.23, P<0.001) and sex (r=0.11, P=0.042), and was found to be higher in women. The score in the depression subscale (HADS-D) correlated with age (r=0.17, P=0.003) and hypertension (r=0.12, P=0.039), but not with sex (r=0.02, P=0.68). When the control subjects were matched for sex and age with the subjects with hypertension, the mean HADS-A score was 5.51±0.41 in 113 hypertensive subjects and 4.38±0.39 in 113 normotensive subjects (P=0.047). The mean HADS-D score was 5.56±0.39 in the hypertensive and 4.76±0.32 in the normotensive subjects (P=0.11). Multiple regression analysis using data from both groups indicated that the HADS-A score was related to the HADS-D score (β=0.49, P<0.001), age (β= −0.25, P<0.001) and sex (β=0.12, P=0.01) (R2=0.28), whereas the HADS-D score was related to the HADS-A score (β=0.48, P<0.001), age (β=0.30, P<0.001), positive smoking status (β=0.13, P=0.004) and lack of exercise habit (β=0.12, P=0.008) (R2=0.31). Hypertension was related to waist circumference, history of parental hypertension and age (R2=0.38, P<0.001). Anxiety and depression scores were rejected as independent variables.

CONCLUSIONS:

Hypertension was associated with anxiety but not depression; however, age, history of parental hypertension and central obesity appeared to have a stronger association with hypertension in adults from Hong Kong.  相似文献   
47.
We investigated the efficacy of 2-chlorodeoxyadenosine (2-CdA) therapy in patients with mycosis fungoides (MF) and the Sezary syndrome (SS). Between February 1991 and November 1993, 21 patients with relapsed or refractory MF/SS were treated with 2-CdA. 2-CdA was administered by continuous intravenous infusion at a dose of 0.1 mg/kg/d for 7 days initially (13 patients), but was subsequently reduced to 5 days (nine patients) due to hematologic toxicity. All patients had failed to respond to at least one prior treatment for MF/SS (median number of total prior therapies, five; median number of systemic prior therapies, three) and had an Eastern Cooperative Oncology Group performance status of two or better. Cycles were administered at 28-day intervals. Assessable patients received at least 5 days of 2-CdA. Fourteen patients received more than one cycle of 2-CdA. An overall response rate of 28% was achieved. Three patients (14%) had a complete response with a median duration of 4.5 months (range, 2.5 to 16). Three (14%) had a partial response with a median duration of 2 months (range, 2 to 4). Fifteen patients (72%) had no response. The most significant toxicities encountered were bone marrow suppression (62% of patients) and infectious complications (62% of patients). Thirty-eight percent of patients experienced no toxicity from 2-CdA. 2-CdA has activity as a single agent in patients with previously treated relapsed MF/SS. Studies in less heavily pretreated individuals with 2-CdA alone or in combination will be undertaken.  相似文献   
48.
We have previously described a unique type of delta beta-thalassemia in a Chinese family characterized by increased expression of the G gamma and A gamma fetal globin genes in the absence of a large deletion in the beta-globlin gene cluster. Our earlier study of the beta-globin gene on this delta beta-thalassemia chromosome showed a promoter mutation in the TATA box. In this report, we describe the results of our study of the fetal globin domain of this delta beta-thalassemia chromosome. We have cloned a 13-kb DNA fragment that includes the G gamma and the A gamma genes and the 3' A gamma enhancer element of this delta beta-thalassemia chromosome. DNA sequence analysis of the G gamma and A gamma-globin genes including their promoters did not show any mutations, but analysis of the putative enhancer element downstream from the A gamma-globin gene showed a C to T substitution 2,401 nucleotides downstream from the A gamma cap site. We performed DNA linkage analysis to determine if this mutation is unique to this chromosome or represents a common polymorphism. Our linkage analysis showed that this mutation is not a common polymorphism and that it is also not an intrinsic part of the haplotype of the chromosome on which it was found. We also studied the interaction of nuclear proteins from erythroid and nonerythroid cells with the DNA sequences surrounding this mutation. We have shown by in vitro DNase I footprinting that this mutation falls within a region that is occupied by a novel DNA-binding protein that binds to this site in nuclear extracts from erythroid, but not nonerythroid cells. The binding of this nuclear protein to DNA appears to be dependent on GATA-1 binding to an adjacent GATA-1 site. We have also developed a new functional assay to compare the activity of the normal and mutant A gamma enhancer elements in erythroid cells. Analysis of the activity of the mutant enhancer shows that the mutation completely eliminates all enhancer activity in this assay. These findings suggest that this mutation of the A gamma enhancer on a chromosome that carries a partially inactivated beta-globin gene may be responsible for the increased expression of both gamma-globin genes seen in this condition.  相似文献   
49.
Interaction of platelet plasma membranes with thrombin-activated platelets   总被引:1,自引:0,他引:1  
Prasanna  HR; Edwards  HH; Phillips  DR 《Blood》1981,57(2):305-312
This study described the binding of platelet plasma membranes to either control or thrombin-activated platelets. Glycoproteins in plasma membranes isolated from human platelets were labeled by oxidation with periodate followed by reduction with [3H]NaBH4. Labeled membranes were incubated with either control or thrombin-activated platelets. The amount of membranes bound was measured by separating platelets with bound membranes from solution by rapid centrifugation through 27% sucrose and determining the amount of radioactivity associated with platelets. Five- to sevenfold more membranes bound to thrombin- activated platelets than to control platelets. This enhanced binding of labeled membranes was completely inhibited by an excess of unlabeled platelet membranes. Human erythrocyte membranes had little affinity for either washed or thrombin-activated platelets and therefore did not compete for platelet-membrane binding. Binding of platelet membranes to thrombin-treated platelets was inhibited by prior incubation of the platelets with PGI2 suggesting that the enhanced binding of membranes was to activated platelets. This study demonstrates that the purified platelet membranes have functional sites that can mediate membrane binding to platelets and that quantitation of membrane binding appears to reflect the increased aggregation capability of activated platelets.  相似文献   
50.
Tone recognition is partially subserved by neural activity in the right frontal and primary auditory cortices. First we determined the brain areas associated with tone perception and recognition. This study then examined how regional cerebral blood flow (rCBF) in these and other brain regions correlates with the behavioral characteristics of a difficult tone recognition task. rCBF changes were assessed using H2(15)O positron emission tomography. Subtraction procedures were used to localize significant change regions and correlational analyses were applied to determine how response times (RT) predicted rCBF patterns. Twelve trained normal volunteers were studied in three conditions: REST, sensory motor control (SMC) and decision (DEC). The SMC-REST contrast revealed bilateral activation of primary auditory cortices, cerebellum and bilateral inferior frontal gyri. DEC-SMC produced significant clusters in the right middle and inferior frontal gyri, insula and claustrum; the anterior cingulate gyrus and supplementary motor area; the left insula/claustrum; and the left cerebellum. Correlational analyses, RT versus rCBF from DEC scans, showed a positive correlation in right inferior and middle frontal cortex; rCBF in bilateral auditory cortices and cerebellum exhibited significant negative correlations with RT These changes suggest that neural activity in the right frontal, superior temporal and cerebellar regions shifts back and forth in magnitude depending on whether tone recognition RT is relatively fast or slow, during a difficult, accurate assessment.   相似文献   
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