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排序方式: 共有919条查询结果,搜索用时 15 毫秒
1.
E Flescher M J Dauphinée D Fossum J Ledbetter N Talal 《Arthritis and rheumatism》1992,35(9):1068-1074
OBJECTIVE. To study the effects of a novel A-type retrovirus, detected in cocultures of lip biopsy specimens from Sj?gren's syndrome (SS) patients and a human T cell line, on the infected T cells. METHODS. Interleukin-2 (IL-2) and IL-6 secretion were measured by bioassay and enzyme-linked immunosorbent assay, respectively, in the infected and noninfected cell lines. Surface antigen expression was determined by flow cytometry, using monoclonal antibodies. Protein kinase C (PKC) activity was measured using an enzyme assay kit, and calcium mobilization was assessed with a fluorescent probe. RESULTS. Infected cells expressed less CD4 and IL-6 receptor, but more HLA-DR, compared with noninfected cells. Infected cells also produced less IL-2 and displayed reduced PKC activation and calcium mobilization. A similar defect in calcium mobilization was detected in T cells from SS patients. CONCLUSION. These data suggest a possible involvement of the newly described retrovirus in T cell abnormalities. 相似文献
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Licastro F Grimaldi LM Bonafè M Martina C Olivieri F Cavallone L Giovanietti S Masliah E Franceschi C 《Neurobiology of aging》2003,24(7):921-926
Two different polymorphic regions of the interleukin-6 (IL-6) gene were investigated in patients with Alzheimer's disease (AD) and non-demented controls. The -174 C allele in the promoter region of IL-6 gene was over-represented in AD patients compared to controls and significantly increased the risk of AD. Moreover, the -174 CC genotype was associated with a high risk of the disease in women. The D allele of a variable number of tandem repeat (VNTR) was in strong linkage disequilibrium with the -174 C allele and slightly increased AD risk. On the other hand, the frequency of the VNTR C allele was decreased in patients with AD and was negatively associated with the risk of developing AD. Both the -174 CC and VNTR DD genotypes were also associated with increased IL-6 levels in the blood and brain from AD. These findings suggest that IL-6 may play a multifaceted role in AD by affecting the turnover of the cytokine. 相似文献
4.
Human sperm chemotaxis: both the oocyte and its surrounding cumulus cells secrete sperm chemoattractants 总被引:5,自引:0,他引:5
Sun F Bahat A Gakamsky A Girsh E Katz N Giojalas LC Tur-Kaspa I Eisenbach M 《Human reproduction (Oxford, England)》2005,20(3):761-767
BACKGROUND: Human sperm chemotaxis to pre-ovulatory follicular fluid is well established in vitro. However, it is not known whether the female's oocyte-cumulus complex secretes sperm chemoattractants subsequent to ovulation (for enabling sperm chemotaxis within the Fallopian tube) and, if so, which of these cell types--the oocyte or the cumulus oophorus--is the physiological origin of the secreted chemoattractant. METHODS: By employing a directionality-based chemotaxis assay, we examined whether media conditioned with either individual, mature (metaphase II) human oocytes or the surrounding cumulus cells attract human sperm by chemotaxis. RESULTS: We observed sperm chemotaxis to each of these media, suggesting that both the oocyte and the cumulus cells secrete sperm chemoattractants. CONCLUSIONS: These observations suggest that sperm chemoattractants are secreted not only prior to ovulation within the follicle, as earlier studies have demonstrated, but also after oocyte maturation outside the follicle, and that there are two chemoattractant origins: the mature oocyte and the surrounding cumulus cells. 相似文献
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In this paper Reactive Dissociative Psychosis (RDP) is seen as a post-traumatic stress response and as a subcategory of Brief Reactive Psychosis (BRP). A review of the literature and the evolution of RDP from Hysteria and Hysterical Psychosis are given. Issue is taken with defining the duration of BRP as Brief. The authors argue that long-standing psychotic symptoms may be traumatically induced. The dissociative aspects of RDP as its key feature and the concomitant implications for accurate diagnosis are proposed. The usefulness of applying hypnosis in RDP treatment is summarized in a case study from Janet and detailed in a case from the authors' practice.This article was accepted for publication under the Editorship of Charles Charles R. Figley. 相似文献
7.
Background: This study explored eating habits, nutrient intake, and blood vitamin and mineral levels to determine whether
severely obese subjects (BMI 40-50 kg m−2) post-vertical banded gastroplasty (VBG) or gastric bypass Roux-en-Y (GBR) are at risk of developing compounded under-nutrition.
Methods: A dietary follow-up of 36 VBG and 19 GBR was maintained for 18 months via 7-day food intake diaries and 24-h recalls.
Food intake was analysed for energy and nutrient composition and for its relative amount to recommended dietary allowances
(RDA). Results: Weight loss was greatest during the first 6 months, continued at a slower rate for the next 6 months, nearly
ceasing thereafter. The results following GBR were not substantially different from those following VBG 18 months postoperatively.
The median weight loss at 1 year postoperatively was 48, 46, 48 and 36 kg; expressed as residual excess body weight: 0.2,
16, 13 and 22% for GBR Men, Women, VBG Men, Women, respectively. According to the classification proposed by Reinhold, all
subjects achieved excellent treatment outcomes 18 months postoperatively. Despite the relatively low reported energy intake
(20-50% below RDA), no correlation was found between rate of weight loss and energy intake at 6 months postoperatively. The
intake of most vitamins and minerals was below 50% of RDA during the 18 months follow-up. The increase in energy intake did
not improve the level of the nonenergy-contributing nutrients. Compliance to multivitamin and mineral supplement intake deteriorated
with time. Conclusion: The low to within-normal range of blood vitamin and mineral levels 12 months postoperatively suggests
the slow development of subclinical nutritional deficiency which could jeopardize the subjects' long-term health status. 相似文献
8.
The physiological responses to four levels of radiant heat (R) in combination with two work loads and three ambient humidity levels were studied on seven clothed young men. The globe temperature (tg) ranged from 40 to 74°C; metabolic work load (M) was either 20 or 50% of maximal aerobic capacity (V?02 max); ambient vapor pressure was either 13 or 23 mm Hg; and dry-bulb temperature (tdb) was 38 or 49°C. The criteria for heat strain were the changes in rectal temperature (Tre), mean skin temperature (Tsk), heart rate (HR), and sweating (Sw). Stress was defined by the calculated heat load requiring dissipation (M + R + C = Ereq), the ambient evaporative capacity (Emax), and the skin wettedness (w), defined as the ratio of Ereq/Emax. The progressive increase in R resulted in a concomitant rise of Tre and HR reflecting the physiological strain. Similarly the increase in either M or in the humidity resulted in higher Tre and HR. The changes in R or Emax were best defined by the w, thus w and the physiological responses were highly correlated. For practical application a multiple regression of the increments of HR(ΔHR) on tdb above neutral (25°C) and on tg above tdb was derived as follows: It was concluded that the calculated skin wettedness is most suitable in the evaluation of heat stress. 相似文献
9.
Carolina de Mattos Duarte Hugo Verli Joo Xavier de Araújo-Júnior Isac Almeida de Medeiros Eliezer J. Barreiro Carlos Alberto Manssour Fraga 《European journal of pharmaceutical sciences》2004,23(4-5):363-369
We describe herein the structural optimization of new piperamide analogues, designed from two natural prototypes, piperine 1 and piperdardine 2, obtained from Piper tuberculatum Jacq. (Piperaceae). Molecular modeling studies using semiempirical AM1 method were made in order to establish rational modifications to optimize them by molecular simplification. The targeted compounds (10) and (11) were respectively obtained using benzaldehyde (12) and para-anisaldehyde (13) as starting materials. 1H NMR spectra showed that the target compounds were diastereoselectively obtained as the (E)-isomer, the same geometry of the natural prototypes. These new synthetic amides presented significant hypotensive effects in cardiovascular essays using in vivo methodologies. Compound 11 (N-[5-(4′-methoxyphenyl)-2(E)-pentenoyl]thiomorpholine) showed a potency 10,000 times greater than its prototype 5, evidencing an optimization of the molecular architecture for this class of hypotensive drug candidates. 相似文献
10.