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11.
Kurowska E Kobiałka M Zioło E Strzadała L Gorczyca WA 《Archivum immunologiae et therapiae experimentalis》2002,50(4):289-294
Numerous reports indicate that cyclic 3',5' guanosine monophosphate (cGMP) is involved in the regulation of immune processes. However, the mechanisms responsible for the synthesis of this nucleotide and its signaling pathways in immune cells are still not well recognized. The aim of our studies was to establish: 1) which form of guanylyl cyclase (GC) synthesizes cGMP in murine lymphoid organs and 2) whether the same organs express the isoforms PKG1alpha and/or PKG1beta of protein kinase G, known as possible target for synthesized cGMP. Cells isolated from thymus, lymph nodes, and spleen were treated with activators (SNP, ANP, CNP, STa) of soluble or particulate cyclases. Sodium nitroprusside (SNP) elevated intracellular cGMP 2-fold in thymic and lymph node cells and about 10-fold in spleen cells. Atrial natriuretic peptide (ANP) caused modest but statistically significant increases of cGMP in cells of all three organs. Additionally, spleen cells elevated their cGMP content about 2-fold in response to C-type natriuretic protein (CNP). In cellular homogenates of the all analyzed organs, the antibody anti-PKG1beta stained the 78 kDa band corresponding to the molecular mass of PKG1. Only homogenates of spleen cells were stained by the antibody recognizing PKG1alpha. Our results indicate that in the investigated organs cGMP may be synthesized mainly by soluble GC in response to nitric oxide. The modest increase of cGMP upon stimulation by ANP suggests that in all these organs either exists only a small subpopulation of cells that express particulate cyclase GC-A or GC-A is expressed at very low level. In spleen cells, however, cyclase GC-B appears to be the more active enzyme. Elevated cGMP concentration may in turn activate PKG1beta in thymus, lymph node, and spleen cells and also PKG1alpha in spleen cells. 相似文献
12.
Vclav Vtvi
ka Lubor Forn Paul W. Kincade Jindrich Kope
ek 《European journal of immunology》1986,16(8):901-905
Simultaneous expression of particular immunoglobulin Fc receptors (FcR) was studied on the plasma membranes of murine peritoneal macrophages. This was facilitated by the use of sheep red blood cells (SRBC) and/or synthetic microspheres coated with monoclonal antibodies of different isotypes. It was concluded that a majority of macrophages bear more than one type of FcR; macrophages bearing at least three types of FcR were present in the peritoneal cavity; macrophages bearing Fc mu R did not bind IgE, IgA or IgG; all macrophages bearing Fc alpha R also expressed Fc gamma 2bR, Fc gamma 3R and Fc epsilon R; all macrophages bearing Fc epsilon R also expressed Fc gamma 2bR and Fc alpha R. Except for Fc alpha R, essentially equivalent numbers of FcR-bearing macrophages were detected when antibody-coated SRBC or polymeric microspheres were used. Simultaneous applications of these reagents permitted the most detailed and direct investigations yet performed of multiple FcR expression on individual cells. 相似文献
13.
14.
Ladislav Pila Lucie Kvasni
kov Stanislavsk Roman Kvasni
ka Richard Hartman Ivana Tich 《Nutrients》2021,13(6)
Social media platforms have become part of many people’s lives. Users are spending more and more time on these platforms, creating an active and passive digital footprint through their interaction. This footprint has high research potential in many research areas because understanding people’s communication on social media is essential in understanding their values, attitudes, experiences and behaviors. Researchers found that the use of social networking sites impacts adolescents’ eating behavior. If we define adolescents as individuals between ages 10 and 24 (WHO’s definition), 76% of USA young people at age 18–24 use Instagram, so the Instagram social network analysis is important for understanding young people’s expressions in the context of healthy food. This study aims to identify the main topic associated with healthy food on the Instagram social network via hashtag and community analysis based on 2,045,653 messages created by 427,936 individual users. The results show that users most associate Healthy food with healthy lifestyle, fitness, weight loss and diet. In terms of food, these are foods that are Vegan, Homemade, Clean and Plant-based. Given that young people change their behavior in relation to people’s behavior on social networks, it is possible to use this data to predict their future association with healthy food characteristics. 相似文献
15.
Kiani Zahra Simbar Masoumeh Nazarpour Soheila Rashidi Fakari Farzaneh 《Archives of sexual behavior》2022,51(7):3223-3224
Archives of Sexual Behavior - 相似文献
16.
Since 1993, outpatient radioiodine therapy has been available in Hungary. The reported study evaluated the efficacy of outpatient radioiodine treatment in subjects with hyperthyroidism. The data on 118 patients with Graves' disease and 36 patients with thyroid autonomy were analysed retrospectively. All patients were treated within the period 1994-1997. The activities of radioiodine were individually calculated. The applied dose in Graves' disease was 150 Gy, and in thyroid autonomy 150 Gy or 300 Gy. The efficacy of the treatment were evaluated 3, 6, and 12 months after radioiodine therapy. In patients with persistent hyperthyroidism repeated therapies were performed. Overall the radioiodine therapy was successful in 85% of the Graves' disease patients. The first 150 Gy treatment was effective in 70% of the patients with Graves' disease and in 43% of the patients with increased radioiodine turnover. In thyroid autonomy, the treatment with 150 Gy was successful in 71%, with 300 Gy in 89% of the patients. The efficacy of radioiodine treatment was similar to the results of one dose application. It was concluded, that radioiodine therapy with 150 Gy absorbed dose in Graves' disease and with 300 Gy absorbed dose in thyroid autonomy proved successful by the method of the authors. 相似文献
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18.
Nygren P Csòka K Larsson R Busch C Wester K Malmström PU 《The Journal of urology》1999,162(6):2200-2204
PURPOSE: In vitro tumor models could support the process of development of new cytotoxic drugs and selection of suitable drugs for the individual patient. We investigated whether the testing of tumor cells from patients with kidney or urinary bladder carcinoma by fluorometric microculture cytotoxicity assay (FMCA) could provide clinically relevant data for these tumor types. MATERIALS AND METHODS: A total of 45 tumor samples from patients with kidney or urinary bladder carcinoma were compared with 247 samples of other tumor types with respect to sensitivity to 8 standard and 6 investigational cytotoxic drugs in the FMCA, a 72 hour assay based on the concept of total cell kill. In bladder carcinomas, sensitivity to standard drugs was correlated to various tumor characteristics. RESULTS: The technical success rate for kidney and bladder carcinomas was high; approximately 90% of the samples could be analyzed successfully. Kidney carcinomas were highly resistant to standard drugs and bladder carcinomas essentially as sensitive as carcinomas of the breast and ovary but with a steeper dose-response relationship. In bladder carcinoma there was no clear relationship between tumor stage, grade, ploidy, mitoses or p53 expression and drug sensitivity. Except for suramin, kidney carcinomas were poorly sensitive to the investigational drugs CdA, gemcitabine, paclitaxel, vinorelbine and topotecan. In bladder carcinomas paclitaxel, gemcitabine and suramin showed promising activity. CONCLUSIONS: The FMCA seems suitable for cytotoxic drug sensitivity testing of urinary tract carcinomas. This technique may have a role in new drug development in these tumor types. 相似文献
19.
Lipoma of the uterus is a rare condition usually developing in postmenopausal women. Clinical symptoms and physical signs are similar to those found in leiomyomas. The histiogenesis of these lesions is still unclear. We report a case of a pure intramural lipoma of the uterus illustrating characteristic morphological and histological findings. Additional immunohistochemical studies underline the lipomatous but not leiomyomatous nature of the tumor. 相似文献
20.
Increased expression and secretion of interleukin-6 in patients with Barrett's esophagus. 总被引:6,自引:0,他引:6