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31.
Huang  CH; Johe  K; Moulds  JJ; Siebert  PD; Fukuda  M; Blumenfeld  OO 《Blood》1987,70(6):1830-1835
Blood cells from two unrelated individuals whose erythrocytes exhibit respectively N S-s-U- and MN S-s-U- blood group phenotypes were examined by immunoblotting, periodic acid-Schiff (PAS) staining, and Southern blotting. Protein bands characteristic of delta glycophorin (glycophorin B) were absent from the immunoblots of whole erythrocyte lysates when probed with polyclonal glycophorin antisera and from isolated erythrocyte membranes stained with PAS reagents. Genomic DNA from the two individuals' leukocytes was digested with a panel of restriction enzymes and probed with alpha M glycophorin cDNA obtained from human K562 leukemic cell line. The EcoRI, PstI, and KpnI restriction site patterns were identical to those of S+s+U+ controls in fragment numbers and relative size but differed from controls in band intensities. Restriction mapping with HindIII, PvuII, SacI, MspI, and BamHI revealed that S-s-U- individuals lack fragments that are reproducibly observed in S+s+U+ controls, and most likely encode delta glycophorin. Using truncated 5' and 3' cDNA segments as probes and comparing, in control individuals, hybridization intensities of fragments with amino acid sequence homologies, we have inferred the assignment of restriction fragments to the alpha and delta glycophorin genes. Our results suggest that the absence of delta glycophorin in the two S-s-U- individuals is a result of deletion of the entire delta glycophorin gene. This is the first report of a glycophorin gene deletion.  相似文献   
32.

Background

The effects of vasectomy on spermatogenesis and reproductive parameters are recognized to be specie-dependent with marked differences in levels of perturbations observed.

Objectives

To assess the impact of unilateral vasectomy on testosterone level and other testicular parameters in the male African giant rat (AGR) (Cricetomys gambianus).

Methods

Sixteen adult male AGRs weighing 500–1300 g were recruited for the experiment. Animals were randomly divided into three experimental groups (1–3) and one control (sham operated) group with four rats per group. Experimental vasectomy was done by carefully ligating the vas deferens of the right testis of all the experimental groups (1, 2, and 3) and animals were allowed either 8, 6 and 2 weeks respectively before sacrifice. Sham-operated animals served as the control. Blood samples were collected and assayed for testosterone while testicular tissue was further processed for seminal fluid and histo-pathological analyses.

Results

Spermatogenic parameters indicate a pattern of decline in sperm count and motility between the experimental groups and the control and azoospermia in the eight-week group. Histological alterations were marked by atrophy of seminiferous tubules which was proportional to the duration of vasectomy. Serum testosterone levels were significantly reduced at eight weeks. There was no statistically significant difference between sperm counts of right and left testes except for group 3. Results suggest that unilateral vasectomy of the AGR may have negative impact on the contralateral testis in the male African giant rat.

Conclusion

These preliminary results reveal that unilateral vasectomy in the AGR may result in perturbations of the histo-architecture of the testes with possible decline in function.  相似文献   
33.

Aim

The aim of the present in vitro study was to investigate the potential of a storage medium, probiotic yogurt (Bifidibacterium animalis DN 173010) in comparison with Hank''s balanced salt solution (HBSS), saline and milk in maintaining viable periodontal ligament (PDL) cells on simulated avulsed teeth.

Materials and methods

Thirty-six freshly extracted single-rooted human teeth with closed apices were divided into six experimental groups (N=6). The teeth were extracted as atraumatically as possible and washed in sterile saline solution to eliminate residual blood. Following extractions, the coronal 3 mm of PDL tissues were scraped with a #15 scalpel to remove cells that may have been damaged. The positive and negative controls corresponded to 0 minutes and an 8-hour dry time, respectively. After extraction, the positive control teeth were immediately treated with dispase and collagenase. The negative control teeth were bench-dried for 8 h, with no follow-up storage solution time, and then placed in the dispase and collagenase. The number of viable protective least significant difference PDL cells were counted under a light microscope with a hemocytometer at 20× magnification and analyzed. Statistical analysis of the data was accomplished using Nonparametric ANOVA complemented by Kruskal-Wallis Test and Dunn''s Multiple Comparisons Test.

Results

Positive control was found to be significantly better than the others, there were statistically significant differences between positive control and other test groups (p=0.000). The teeth stored in positive control demonstrated the highest number of viable PDL cells followed in order by probiotic yogurt, HBSS, saline and milk.

Conclusion

Bifidibacterium animalis DN 173010 seems to be an alternative for the temporary storage of avulsed teeth, due to high number of viable PDL cells. Probiotics may be suitable transport media for avulsed teeth, but further research is warranted using the commercially available products.Key words: dental trauma, probiotic, storage media  相似文献   
34.
Uncooked, lactobacilli-rich, vegan food and rheumatoid arthritis   总被引:1,自引:0,他引:1  
We tested the effects of an uncooked vegan diet, rich in lactobacilli, in rheumatoid patients randomized into diet and control groups. The intervention group experienced subjective relief of rheumatic symptoms during intervention. A return to an omnivorous diet aggravated symptoms. Half of the patients experienced adverse effects (nausea, diarrhoea) during the diet and stopped the experiment prematurely. Indicators of rheumatic disease activity did not differ statistically between groups. The positive subjective effect experienced by the patients was not discernible in the more objective measures of disease activity (Health Assessment Questionnaire, duration of morning stiffness, pain at rest and pain on movement). However, a composite index showed a higher number of patients with 3-5 improved disease activity measures in the intervention group. Stepwise regression analysis associated a decrease in the disease activity (measured as change in the Disease Activity Score, DAS) with lactobacilli-rich and chlorophyll-rich drinks, increase in fibre intake, and no need for gold, methotrexate or steroid medication (R2=0.48, P=0.02). The results showed that an uncooked vegan diet, rich in lactobacilli, decreased subjective symptoms of rheumatoid arthritis. Large amounts of living lactobacilli consumed daily may also have positive effects on objective measures of rheumatoid arthritis.   相似文献   
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We studied the efficacy of a home-made urease test (HUT) in the detection of Helicobacter pylori (HP) infection in patients undergoing upper gastrointestinal endoscopy. In the first phase of the study, two antral biopsies each were obtained from 43 patients for urease tests using the CLOtest and a home-made buffered 2% urea solution with phenol red as indicator at pH 6.8 (2% HUT). Twenty-six patients (60.5%) were HP positive, both by the 2% HUT and CLOtest with 100% concordance. In the second phase of the study three antral biopsies each and blood were obtained from 42 patients for the determination of HP status using a 10% HUT and a combination of culture and serology. Twenty-three patients (54.8%) were HP positive using the 10% HUT, while 32 patients (76.2%) were positive using the combination of 2 tests. Compared to this the sensitivity and specificity of the 10% HUT were 72% and 100% respectively. The CLOtest produced a colour change in a shorter time than the 2% and 10% HUT (median 1 hour versus 10 hours versus 16 hours p < 0.0001). In the third phase of the study, we observed that by doubling the biopsy size, the time required to obtain a colour change was significantly reduced (median 4.5 hours versus 10 hours p < 0.05). The HUT is easy to prepare, cheap, sufficiently sensitive and it is reliable enough to start treatment when positive. With 100% concordance and 1% the cost per test when compared to the commercially available CLOtest; the 10% HUT is hereby recommended for the detection of UP infection in our region.  相似文献   
38.

Background

Knee osteoarthritis is a chronic medical condition of public health importance in Nigeria which causes disability and impacts daily activities in the sufferers. This study aimed to describe the physical functionality and self-rated health status of adult patients with clinical knee osteoarthritis presenting at the Family Medicine Department, University College Hospital, Ibadan, Nigeria.

Methods

This was a cross-sectional study of 400 respondents. Knee osteoarthritis was diagnosed clinically using the criteria of the American College of Rheumatology. Morbidities, self-rated health status and physical functionality of the respondents were also assessed.

Results

Knee osteoarthritis was diagnosed in 46(11.5%) respondents. Respondents with knee osteoarthritis significantly rated their health worse than those without knee osteoarthritis (p <0.0001). Experience of pain, stiffness and performance of daily activities were significantly worse among respondents with knee osteoarthritis. Those who had knee osteoarthritis had significantly higher waist (p <0.0001), hip (p <0.0001) and knee circumferences (p <0.0001) respectively. Logistic regression analysis showed increasing age (OR=1.103; 95% CI=1.022 – 1.191), self-rated health worse than six months ago (OR=12.562; 95% CI=1.178–125.243), experience of stiffness after waking up in the morning (OR=12.758; 95% CI=3.572–45.569), stiffness after sitting/lying down/resting (OR=21.517; 95% CI=2.213–209.220) and waist circumference (OR=1.225;95% CI=1.017–1.477) to be the most significantly associated with knee osteoarthritis.

Conclusion

Knee osteoarthritis significantly impairs the health and daily activities of adult patients in Ibadan, Nigeria. Healthcare workers need to screen adult patients routinely at first-contact to detect knee osteoarthritis clinically early and manage appropriately.  相似文献   
39.
Background: In the progression of their disease, Alzheimer's disease (AD) patients have been observed to demonstrate various clinical features reminiscent of children. Based on behavioral, neurological and neuropathological findings, Reisberg et al. noted the relationships between development and dementia and proposed the ‘retrogenesis’ model. Methods: The functional assessment staging procedure (FAST) was used for assessment of functional ability, and the Tanaka–Binet intelligence scale (TB scale) was used to assess intellectual ability in 24 patients with moderate to severe AD. Results: Overall, there was a significant Spearman's correlation between the FAST stage and the basic age (BA) value (r = ?0.85, P < 0.01). The BA by the TB scale was significantly different between FAST stages 5 and 6 to 7. The mean (standard error [SE]) BA values of FAST stages 5 and 6 were 4.2 (0.9) and 2.3 (0.7), respectively, the latter being significantly lower than the former (F = 10.2, P < 0.01 one‐way anova ). The TB scale could not assess the BA of the FAST stage 7 patients because of floor effects. Conclusion: Although further investigation using larger samples would be needed, the findings support the general concordance of intellectual and functional decline in AD with the converse developmental acquisition of the same capacities, as hypothesized in the retrogenesis model.  相似文献   
40.
研究并讨论了在模拟状态下飞行员的心理-生理活动的焦虑水平。焦虑指的是一种特定的性格状态,从事危险职业的人由于经常性地受到紧张因素的影响,会产生长期的或暂时的焦虑。研究结果表明,当选拔在复杂环境条件下工作的操作者时,应优先考虑低焦虑水平的人;而当小组共同完成任务时,应着重考虑焦虑水平相当的人。  相似文献   
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