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51.
Primary biliary carcinoma: CT evaluation   总被引:19,自引:0,他引:19  
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咪苯嗪酮(CI-914)能抑制大鼠血小板环氧酶和TXA2合成酶产物HHT的生成,而对脂氧酶产物12-HETE的生成仅高浓度药物才有弱的抑制作用,提示CI-914主要影响花生四烯酸(AA)环氧酶途径,而对脂氧酶途径影响较少。在大鼠血小板和中性白细胞CI-914能抑制TXA2的生成,同时CI-914还可使白细胞6-keto-PGF1a和血小板PGE2的产生量显著增加,提示CI-914在这两种细胞引起了AA的转向合成。上述结果基本证实,CI-914在大鼠中性白细胞和血小板对TXA2合成酶具有选择性抑制作用。  相似文献   
54.
To investigate the role of central neurotransmitters in the pathogenesis of migraine, we measured cerebrospinal fluid (CSF) levels of certain amino acids (glycine, taurine, glutamine) and metabolites of biogenic amines (5-hydroxyindoleacetic acid and homovanillic acid) in 38 migraine patients and compared them with the levels from 10 headache-free controls. The levels of taurine, glycine and glutamine were significantly higher in the migraine patients (p < 0.0001 for taurine and glycine; p < 0.0009 for glutamine); there were no significant differences among the three migraine subgroups (infrequent migraine, frequent migraine and transformed migraine). In seven patients subsequently treated with divalproex sodium, CSF taurine levels decreased significantly from pretreatment baseline values. These data support the concept that migraine is at least in part a disorder of central neurotransmission.  相似文献   
55.
We compared patient morbidity associated with temporomandibular joint (TMJ) arthrography using both meglumine/sodium diatrizoate (60%) and the new monoacidic dimer, Hexabrix, in a double-blind randomized clinical trial in 31 patients. Patients experienced maximal discomfort from TMJ arthrography with the initial joint filling and joint distension; this rapidly resolved over 10 minutes. Delayed exacerbation of pain is less than described for shoulder arthrography. The newer contrast media promise to decrease patient morbidity with arthrography.  相似文献   
56.
This investigation was designed to determine the effect of the intrauterine contraceptive device (IUD) on the early phase of sperm transport. Previously we have shown that in normal midcyle subjects the maximal number of sperm recovered from the oviducts occurred between ten and 45 minutes after vaginal insemination. Four normal subjects, three of whom had IUD's in situ for at least eight months (copper T, Dalkon shield, and loop) and one a loop for one month, were studied in a similar manner. All subjects were inseminated at midcycle and had bilateral abdominal salpingectomies 15 to 30 minutes after insemination. No sperm were present in the oviducts of any of the subjects. The results of this study indicate that the IUD interferes with sperm transport in the human being. Additional subjects are now being studied at different time intervals after insemination in order to determine the entire effect of the IUD upon sperm transport.  相似文献   
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1 临床资料患者、女性、38岁、因右小细胞肺癌术后16 mo,间断性头痛10 mo,加重1 wk后于2003-01-01入院.在2002-02因枕部疼痛,行头颅CT示: 脑多发转移癌.行多次头颅局部X-刀、γ-刀加全脑预防性放疗和化疗,疗效达部分缓解.2002-12末头痛症状复发,约1.5 h发作1次,伴短暂意识丧失、喷射状呕吐和四肢抽搐.  相似文献   
59.
The cellular receptor for urokinase-type plasminogen activator (uPAR) binds pro-urokinase (pro-uPA) and facilitates its conversion to enzymatically active urokinase (uPA). uPA in turn activates surface- bound plasminogen to plasmin, a process of presumed importance for a number of biologic processes including cell migration and resolution of thrombi. We have previously shown that uPAR is expressed on the plasma membrane of circulating neutrophils, and we now report that stimulation with phorbol myristate acetate (PMA), FMLP, or tumor necrosis factor- alpha results in a rapid increase in the expression of uPAR. This process is accompanied by an increased cell-associated plasminogen activation after preincubation of neutrophils with pro-uPA in vitro. By subcellular fractionation of unstimulated neutrophils, 50% of uPAR is recovered in fractions containing latent alkaline phosphatase, corresponding to an intracellular compartment of easily mobilizable secretory vesicles distinct from both primary and specific granules, whereas the remaining 50% of uPAR is associated with a compartment eluting close to the specific granules. In contrast, the ligand pro-uPA is primarily (approximately 80%) found in the specific granules, but small amounts of pro-uPA/uPA (approximately 20%) coelute with latent alkaline phosphatase. Stimulation of neutrophils with FMLP results in translocation of uPAR as well as of pro-uPA from the secretory vesicles, whereas stimulation with PMA is required to translocate material from specific granules. Flow cytometry of neutrophils saturated with exogenous diisopropyl fluorophosphate-uPA shows a large excess (approximately 90%) of unoccupied uPAR on resting as well as FMLP- and PMA-stimulated neutrophils, suggesting a possible role for exogenous pro-uPA in providing neutrophils with a potential for plasminogen activation. These processes may be important for neutrophil extravasation and migration through extracellular matrix and for the contribution of neutrophils to resolution of thrombi.  相似文献   
60.
Adler  A; Albo  V; Blatt  J; Whiteside  TL; Herberman  RB 《Blood》1989,74(5):1690-1697
Activation and expansion in culture with rIL-2 of peripheral blood (PB) and/or bone marrow (BM) specimens derived from children with ALL and ANLL, with active disease (AP) and in remission were studied (RP). Baseline NK cytolytic activity from AP was found to be depressed, whereas RP-derived cells had normal NK activity, as assayed against K562 targets. Culture in rIL-2 significantly enhanced the NK activity of both AP- and RP-derived cells and generated LAK activity, as assayed by 4-hour 51Cr release, against NK-resistant Raji cell line and against fresh, allogeneic, and autologous tumor cells. Lytic activity against fresh, cryopreserved leukemia blasts was of lower than that found against cell lines. In three patients higher lytic activity against autologous than against allogeneic blasts was demonstrated. Expansion in culture with rIL-2 varied from twofold to 120-fold. rIL-2 activation and expansion was better in RP than in AP. The predominant phenotype of activated cells, as determined by flow cytometry, was [mean % (SD)]: CD3- = 54 (12), CD8+ = 55 (17), and NKH1+ = 26 (7). The consistently high level of CD8+ cells was accompanied by very low levels of CD4+ cells: mean = 11% (14). Double-marker analysis showed mean of 33% (10) for CD3+/NKH1+ cells and mean = 32 (11) for CD8+/NKH1+ cells, implying that these populations were overlapping. Kinetics of expression of cell surface markers during 2 to 3 weeks in culture showed that CD8+ and NKH1+ enrichment occurred during the first week and lasted for up to 4 weeks, whereas CD4+ expression decreased after the second week. A significant decrease in the expression of IL-2 receptors (CD25) was observed from the second week of culture. This study shows the feasibility of in vitro generation of killer cells from PB and BM of pediatric leukemia patients.  相似文献   
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