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21.
The aim of this study was to investigate whether lymphocyte vaccination can prevent diabetes occurring in the non-obese diabetic (NOD) mouse, an animal model of human insulin-dependent diabetes mellitus (IDDM). The lymphocyte vaccine was composed of lymphocytes isolated from the spleens of diabetic NOD mice, activated in vitro using concanavalin A (Con A) and rendered immunogenic using glutaraldehyde treatment. These cells were used to vaccinate mice at 6 weeks with boosters at weeks 10, 14 and 18. The animals were then monitored for signs of diabetes until week 30. Twenty-eight NOD mice (11 male, 17 female) were T-lymphocyte vaccinated while 35 littermates (14 male, 21 female) were sham vaccinated with the vaccine carrier, as control mice. The percentage of mice remaining non-diabetic was 50% in the T-lymphocyte-vaccinated group compared with 20% in control mice (P < 0.05). When the results were divided according to sex of the mouse the percentage of female NOD mice remaining non-diabetic was 47.1% in the T-lymphocyte-vaccinated group compared to only 9.4% in the controls (P < 0.01), while in the males there was no significant difference between the groups. These results suggest that T-lymphocyte vaccination can prevent diabetes in NOD mice and that it has its greatest effect in females. The therapy is apparently safe and its efficacy indicates that it may be of value in prediabetes in man.  相似文献   
22.
In anesthetized, artificially ventilated guinea pigs, intranasal and intravenous administration of albuterol produced the same maximum degree of protection against bronchoconstriction induced by bilateral electrical stimulation of the cervical vagal nerves. Intranasal albuterol showed a slower onset of action than intravenous albuterol and exhibited equivalent cardiovascular side effects for the same level of bronchoprotection. Accordingly, intranasal albuterol may represent an alternative to metered-dose inhalation for prophylaxis and treatment of bronchoconstriction in humans.  相似文献   
23.
An approach for 3D bone tissue generation fromembryonic stem (ES) cells was investigated. The ES cells wereinduced to differentiate into osteogenic precursors, capable ofproliferating and subsequently differentiating into bone-formingcells. The differentiated cells and the seeded scaffolds werecharacterized using von Kossa and Alizarin Red staining, electronmicroscopy, and RT-PCR analysis. The results demonstrated thatES-derived bone-forming cells attached to and colonized thebiocompatible and biodegradable scaffolds. Furthermore, thesecells produced bone nodules when grown for 3–4 weeks inmineralization medium containing ascorbic acid andbeta-glycerophosphate both in tissue culture plates and inscaffolds. The differentiated cells also expressed osteospecificmarkers when grown both in the culture plates and in 3Dscaffolds. Osteogenic cells expressed alkaline phosphatase,osteocalcin, and osteopontin, but not an ES cell-specific marker,oct-4. These findings suggest that ES cell can be usedfor in vitro tissue engineering and cultivation of graftable skeletal structures.  相似文献   
24.
Low serum concentrations of the fourth component of complement (C4) are found in insulin dependent diabetes, and may be important in the aetiology of the disease. To ascertain whether function of C4 is also impaired both its haemolytic activity and its concentration were measured in 34 insulin dependent diabetics, 15 non-insulin dependent diabetics, 20 healthy subjects, and 12 pairs of monozygotic twins discordant for insulin dependent diabetes. C4 function was measured by a radial immune haemolytic assay, and C4 concentration by laser nephelometry. Both measurements were significantly lower in insulin dependent diabetics (C4 function: median 47%, range 4-100%; C4 concentration: 0.22 g/l, 0.10-0.38 g/l) than in non-insulin dependent diabetics (67%, 33-138%, p less than 0.01; 0.27 g/l, 0.16-0.50 g/l, p less than 0.02) and controls (74%, 33-138%, p less than 0.01; 0.27 g/l, 0.18-0.40 g/l, p less than 0.03). C4 function and concentration were lower in both diabetic (48%, 12-100%; 0.17 g/l, 0.08-0.31 g/l) and non-diabetic twins (47%, 12-100%; 0.17 g/l, 0.07-0.36 g/l) than controls (p less than 0.01; p less than 0.01). Thirteen (38%) of the insulin dependent diabetics had a reduction in either C4 function or concentration, but in only five were both features reduced. Values of function and concentration were strongly correlated in both diabetic and non-diabetic twins (r = 0.95, p less than 0.001; r = 0.92, p less than 0.001). These results show defects in C4 function and concentration in insulin dependent diabetes, which--being present in the non-diabetic co-twin of diabetics--may represent a genetic predisposition to the disease.  相似文献   
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66 unrelated patients from Southern India with Duchenne Muscular Dystrophy (DMD) were studied for intragenic deletion in 18 exons and Pm region of the DMD gene using multiplex PCR. Of these 41 (62.1%) showed intragenic deletions. 78% of the deletions were located at the distal hotspot region (44-55 exons) and 22% of the deletions were located at the proximal region (exon 2-19). Exon 50 is most frequently deleted. Deletions in isolated cases were significantly more compared to familial cases. The lower incidence reported from South India compared to North India, is suggestive of variations in the Southern and Northern population.  相似文献   
28.
We computed skin-test sensitivity levels in 485 adults puncture-tested with eight standardized, high-quality inhalant allergens tested at single concentrations. In order to quantitate the "average" IgE-mediated skin sensitivity of each subject, we used both nonparametric and parametric statistical methods to generate two "allergy indices" (Allergy Index I and Allergy Index II) based on sensitivity end-point data from the subpopulations of individuals positive to six of the eight allergens. For the 192 skin test-positive subjects, Allergy Index I and Allergy Index II were significantly correlated with each other (rs = 0.98, p less than 0.001) and with the number of positive skin-test reactions (rs congruent to 0.9, p less than 0.001) as well as with log[total serum IgE] (r congruent to 0.4, p less than 0.01). In 102 ragweed-positive subjects, log[specific IgE to ragweed] was significantly correlated with ragweed-specific "ragweed indices I and II" (r congruent to 0.6, p less than 0.01). Furthermore, the average daily symptom scores reported by 14 ragweed-positive subjects during the ragweed pollination season were significantly correlated with ragweed indices I and II (p less than 0.05). We propose the use of Allergy Index II in epidemiologic and genetic studies of allergic phenotypes as well as in clinical decisions for diagnosis and immunotherapeutic intervention.  相似文献   
29.
Conventional indirect haemagglutination test was performed in rhesus monkey sera (collected from Plasmodium knowlesi infected animals) with and without prior treatment of sera with 2-mercapto-ethanol (2-ME). Surprisingly, many sera samples showed significant enhancement of final titre with 2-ME. The 2-ME enhancement effect was more pronounced in the sera of hyperimmune monkeys on further injection of antigen or parasites. It was also noticeable in the sera during primary drug-suppressed P. knowlesi infection and appeared to have a bearing on the immune status of the animals to rechallenge. The use of a soluble antigen prepared from P. knowlesi infected erythrocytes was found to be essential in IHA test to demonstrate the 2-ME enhancement effect. Antigen prepared from freed parasites (commonly used) failed to show a similar effect in IHA. The possible role of certain T-lymphocyte products - antigen binding, non-agglutinating, 2-ME sensitive molecules - in malarial immunology has been proposed.  相似文献   
30.
The transperineal percutaneous template permanent iodine interstitial brachytherapy under "C-arm" fluoroscopic guidance is a simple, easily-learned, accurate and rapid procedure which can be performed without subjecting the patient to celiotomy. We have treated 58 patients by the transperineal percutaneous permanent interstitial brachytherapy. The use of transperineal percutaneous technique with C-arm fluoroscopic guidance improves the symmetry and dosimetry of the implant. This results in reduction of the incidence of chronic radiation-induced complications. In the group of 22 patients who underwent brachytherapy without celiotomy and lymphadenectomy and without adjuvant external-beam radiotherapy, there were no major complications.  相似文献   
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