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11.
The functional of B-L (Ia-equivalent)-positive (B-L+) adn -negative (B-L-) chicken peripheral blood lymphocytes (PBL) was studied in vitro and in vivo. The PBL were first stained in direct immunofluorescence tests with a fluorescein isothiocyanate-labelled anti-B-L alloantiserum and then separated by means of a fluorescence-activated cell sorter. In agreement with our previous findings, B-L- cells showed functional properties of T lymphocytes, responding to concanavalin A and phytohaemagglutinin-P in vitro and inducing a graft-versus-host (GVH) reaction when injected into allogeneic embryos. Sorted B-L+ gave no responses in any of these assays. Neither B-L+ nor B-L- cells, when tested alone, responded significantly to pokeweed mitogen, but mixtures of the two restored the responsiveness to that of the original unsorted suspension. Of the B-L+ PBL, 10% were T cells, which may account for the low GVH reactivity given by this population. 相似文献
12.
1. A systematic study has been made of the sensitivity of identified sensory and motoneurons in the leech central nervous system to chemical transmitter substances. 2. The following substances elicited responses from the cell bodies of individual neurons: acetylcholine, 5-hydroxytryptamine, gamma-aminobutyric acid, glutamic acid, glycine, dopamine, and norepinephrine. Since the cell bodies of leech neurons are free of synapses, the receptors that give rise to these responses are extrasynaptic. 3. Sensory and motoneurons of different function had characteristic complements of extrasynaptic receptors. For example, mechanosensory cells responding to light touch, to pressure, and to noxious stimuli could be distinguished by their responses to iontophoretically applied compounds. For one of these modalities (nociceptive), neurons with different receptive fields but otherwise similar properties had markedly distinct extrasynaptic receptors. The possible significance of extrasynaptic receptors is discussed. 相似文献
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14.
A. PIONA L. LA ROSA A. TINCANI D. FADEN† G. MAGRO‡ S. GRASSO‡ F. NICOLETTI G. BALESTRIERI P. L. MERONI 《Scandinavian journal of immunology》1995,41(5):427-432
In the present study we evaluated the effect of passive transfer of a mouse monoclonal (CAM) or a human polyclonal anti-cardiolipin IgG on pregnancy outcome in BALB/c mice. The mice were immunized through the tail vein immediately after mating with 10 μg of monoclonal or polyclonal anti-cardiolipin antibodies. Two other groups of mice were given a mouse irrelevant monoclonal antibody or normal human polyclonal IgG respectively, at the same dose. In mice immunized with monoclonal or polyclonal anti-cardiolipin antibody we observed a significant increase in the number of fetal resorptions and a significant reduction of the mean weights of the embryos and the placentas. In mice immunized with CAM we also found a significant decrease in the number of healthy pups, while mice infused with human aCL antibody expressed a significant reduction in the fecundity rate. The histological examination showed widespread thrombosis and necrosis in the placentas derived from the mice immunized with the anti-cardiolipin antibodies. The model supports a possible direct pathogenetic effect of anti-phospholipid antibodies in recurrent fetal loss and points out that thrombotic events at placental level can be instrumental in the pathogenesis of the obstetric complications. 相似文献
15.
目的:应用微乳液反应法制备磺胺嘧啶银均匀微晶,均匀制得的微晶的粒径大小约为2~4um,均匀微晶的结晶性好,纯度高。用均匀设计方法优化条件,制备的均匀的微晶平均粒径大小为2.09um,实验结果达到预测结果要求。结论:用微乳液反应法能获得磺胺嘧啶银均匀微晶。 相似文献
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Economic costs of functional dyspepsia 总被引:5,自引:0,他引:5
Dyspepsia is defined as chronic or recurrent symptoms believed to originate in the upper gastrointestinal tract. When routine investigation results in no identifiable explanation for those symptoms patients are labelled as having functional dyspepsia. In community-based surveys, approximately 30% of the otherwise apparently healthy population report dyspeptic symptoms and the majority are believed to have functional dyspepsia. Although only 1 in 4 or 5 patients make use of healthcare resources, this patient category is one of the largest in ambulatory care (1.6 to 5% of all consultations in general practice). The annual frequency of consultations for functional dyspepsia in Sweden has been estimated at 47 per 1000 population. In consequence of its high prevalence and associated absenteeism, the total costs of functional dyspepsia are considerable. In Sweden in 1981, the costs were estimated at $US55 000 per 1000 population ($US113 630 in 1991 dollars). The most cost-effective management strategy remains to be defined. Evidence is accumulating that the traditional 'wait-and-see' policy with initial empirical therapeutic trials without investigation may not be the most cost conserving strategy. 相似文献
18.
Non-invasive detection of fecal protein kinase C betaII and zeta messenger RNA: putative biomarkers for colon cancer 总被引:2,自引:0,他引:2
Davidson LA; Aymond CM; Jiang YH; Turner ND; Lupton JR; Chapkin RS 《Carcinogenesis》1998,19(2):253-257
We have developed a non-invasive method utilizing feces, containing
sloughed colonocytes, as a sensitive technique for detecting diagnostic
colonic biomarkers. In this study, we used the rat colon carcinogenesis
model to determine if changes in fecal protein kinase C (PKC) expression
have predictive value in monitoring the neoplastic process. Weanling rats
were injected with saline or azoxymethane (AOM) and 36 weeks later fecal
samples and mucosa were collected, poly A+ RNA isolated, and quantitative
RT-PCR performed using primers to PKC betaII and zeta. Fecal PKC betaII and
zeta mRNA levels were altered by the presence of a tumor, with
tumor-bearing animals having a 3-fold higher (P < 0.05) PKC betaII
expression as compared with animals without tumors. In addition,
AOM-injection increased mucosal PKC betaII mRNA expression compared with
saline controls. No effect of tumor incidence on mucosal PKC betaII
expression was observed. In contrast, fecal PKC zeta expression was
2.5-fold lower (P < 0.05) in animals injected with azoxymethane versus
saline. Since tumor incidence exerts a reciprocal effect on fecal PKC
betaII and zeta mRNA expression, data were also expressed as the ratio
between PKC betaII and zeta. The isozyme ratio was strongly related to
tumor incidence, i.e. ratio for animals with tumors was 2.18 +/- 1.25,
animals without tumors was 0.50 +/- 0.16, P = 0.025. We demonstrate that
the expression of fecal PKC betaII and zeta may serve as a noninvasive
marker for development of colon tumors. A sensitive technique for the
detection of colon cancer is of importance since early diagnosis can
substantially reduce mortality.
相似文献
19.
Burch PA Richardson RL Cha SS Sargent DJ Pitot HC Kaur JS Camoriano JK 《The Journal of urology》2000,164(5):1538-1542
PURPOSE: We examined the role of paclitaxel and cisplatin as first line therapy for metastatic urothelial cancer. MATERIALS AND METHODS: A total of 34 patients were enrolled in this study, and all were eligible for treatment and assessable for response. Patients received 135 mg./m.2 paclitaxel intravenously for 3 hours followed by 70 mg./m.2 cisplatin for 2 hours every 3 weeks to a maximum of 6 cycles. RESULTS: Of the patients 70% experienced a major response to treatment, which was partial/regression in 38% and complete in 32%. Toxicity was manageable with no episodes of grade 4 leukopenia or thrombocytopenia. Nonhematological toxicities included primarily nausea, anorexia and neuropathy, which rarely were severe. CONCLUSIONS: This regimen of paclitaxel and cisplatin is effective, safe and convenient to administer in an outpatient setting for advanced urothelial cancer. 相似文献
20.