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51.
目的 探讨血清肌钙蛋白Ⅰ(cTn-I)对急性脑血管病(ACVD)后心肌损伤的诊断价值.方法 检测160例ACVD患者入院后24h内、3d、7d的血清cTn-I和肌酸激酶同工酶(CK-MB),比较不同病程、不同类型、不同病情程度ACVD患者血清cTn-I和CK-MB的测定结果,观察预后与cTn-I、CK-MB的关系.结果 病后24h内和7d血清cTn-I较CK-MB的阳性率高;脑出血和重症患者病后7d cTn-I仍增高;病后30d内死亡者的cTn-I和CK-MB增高比例高于存活者.结论 血清cTn-I对ACVD后心肌损伤的检测具有比CK-MB更高的敏感性、特异性和更宽的诊断窗口.  相似文献   
52.
The effect of p.o. administration of tea on nitrosamine-induced carcinogenesis was investigated. Female A/J mice were given N-nitrosodiethylamine (NDEA) (10 mg/kg) p.o. once a week for 8 weeks and were killed 16 weeks after the last dose. More than 90% of the mice had forestomach and lung tumors. The animals had an average of 8.3 forestomach and 2.5 lung tumors/mouse. With 0.63 or 1.25% green tea infusion (12.5 g green tea leaves brewed with 1 liter of boiling water) as the sole source of drinking water for the entire experimental period, the pulmonary tumor incidence was decreased by 18 or 44%, and the tumor multiplicity was reduced by 36 or 60%, respectively. The treatments also decreased the forestomach tumor incidence by 18 or 26% and tumor multiplicity by 59 or 63%, respectively. Administration of 0.63 or 1.25% green tea infusion, either during the NDEA treatment period only or starting 1 week after the completion of NDEA treatment, also decreased the pulmonary tumor incidence and multiplicity and the forestomach tumor multiplicity. The inhibitory effects of green tea infusion were also observed in a similar experiment using a higher dosage of NDEA (20 mg/kg). Treatment of female A/J mice with a single dose (103 mg/kg) of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) resulted in the formation of pulmonary adenomas in almost all of the animals with an average of 9.3 tumors/mouse after 16 weeks. When 0.6% decaffeinated green tea or black tea extract was given during the NNK-treatment period, tumor multiplicity was reduced by 67 or 65%, respectively. When the tea extract was given after the NNK-treatment period until the end of the experiment, 0.6% green tea extract decreased the tumor incidence and multiplicity by 30 and 85%, respectively. In this protocol, 0.6% black tea extract reduced tumor multiplicity by about 63% but did not significantly affect the tumor incidence. The results clearly demonstrated an inhibitory action of green tea and black tea on nitrosamine-induced tumorigenesis.  相似文献   
53.
表皮生长因子及其受体与流产关系的探讨   总被引:4,自引:0,他引:4  
采用放射免疫竞争抑制饱和分析法,检测47例难免流产患者,65例人工流产及20例健康非孕妇女血清表皮生长因子(EGF)水平;同时采用免疫组织化学法检测流产者胚胎组织中表皮生长因子受体(EGFR)表达程度。结果:人工流产组血清EGF水平高于自然流产及非孕妇女,而自然流产与非孕妇女差异无显著性;胚胎组织中EGFR阳性表达率人工流产组明显高于自然流产组。提示:EGF通过与其受体结合对妊娠维持、胚胎及胎儿的  相似文献   
54.
The rat lung and nasal cavity are two target organs for carcinogenesis by 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). In order to characterize further the enzymes involved in the bioactivation of NNK, detailed kinetic and inhibitory studies were conducted with rat lung and nasal mucosa microsomes, and the results were compared with previous studies. The enzymes in rat lung microsomes catalyzed the alpha-hydroxylation, pyridine N-oxidation and carbonyl reduction of NNK. The apparent Km for the formation of the NNK-derived keto aldehyde, NNK-N-oxide, the NNK-derived keto alcohol and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol were 28.8, 10.4, 7.0 and 178.1 microM respectively. In rat nasal microsomes, alpha-hydroxylation was the predominant pathway and the rate was approximately 200 times higher than that in lung microsomes. The apparent Kms for keto aldehyde and keto alcohol formation in rat nasal microsomes were 9.6 and 10.1 microM respectively. The cytochrome P450 inhibitors metyrapone and carbon monoxide markedly inhibited the metabolism of NNK in both rat lung and nasal microsomes. In rat lung microsomes, alpha-naphthoflavone and monospecific antibodies against P450s 1A2, 2A1 and 2B1 inhibited the formation of keto aldehyde by 39, 46, 64 and 23% respectively. In rat nasal microsomes, alpha-naphthoflavone and antibodies against P450s 1A2, 2A1 and 3A inhibited the metabolism of NNK by 80, 35, 20 and 14% respectively. The results indicate that cytochromes P450 play a major role in the metabolic activation of NNK in rat lung and nasal microsomes, and that there are tissue-related differences in NNK metabolism.  相似文献   
55.
小切口胆囊切除术108例临床观察   总被引:1,自引:0,他引:1  
本文报告腹部切口5-8cm的小切口胆囊切除术108例,与同期大切口胆囊切除术相比,具有创伤较小、恢复较快、并发症少、切口疤痕小的优点,虽不如腹腔镜胆囊切除术(LC)的疼痛轻、恢复快,但并症比LC少,只要适应症选择得当,在术者的经验和技术较成熟的情况下,不昔为一种可供选择的方法。  相似文献   
56.
Summary The authors have prepared the artificial bone of porous tricalcium phosphate ceramics according to an appropriate formula and manufacturing technology. Physical and chemical testing shows that it possesses several distinguishing features: the communicating pores and macro/micropores; mean pore size, 380 μm (from 240 μm to 510 μm); porosity, 46.4 %; and compressive strength, 97.4 kg/cm2. It consists of CaO (49.09 %) and P2O5 (48.84 %). The testing of its biocompatibility shows that it is devoid of systemic or local toxicity, and free of irritation or foreign body response in tissues, and it does not result in hemolysis or mutation. The new bone readily grows into its pores with direct contact to the implanted material. 11 cases of bone defects were treated with this artificial bone with satisfactory results.  相似文献   
57.
Extracellular phospholipase A2 (PLA2) is a proinflammatory enzyme found especially in the inflammatory exudate to modulate blood flow to areas of antigen stimulation. In this study we found that PLA2 exerted a biphasic effect on the proliferation of phytohemagglutinin (PHA)-stimulated human mononuclear cells (PHA MNC). At low concentrations range from 0.001 to 1 U/ml, PLA2 enhanced the proliferation of PHA MNC (maximal increase was 37.0 +/- 5.67%). Conversely, at concentrations over 10 U/ml, PLA2 markedly suppressed the PHA-induced MNC proliferation (maximal decrease was 88.86 +/- 2.89%). PLA2 was non-toxic to lymphocytes after three days culture, unless the concentration was higher than 100 U/ml. The membrane polarization of PHA-stimulated lymphocytes was also increased by PLA2 at a low concentration. In addition, PLA2 displayed a similar effect on the proliferation of streptokinase-streptodornase (SK/SD) or allogeneic cell stimulated lymphocytes. The change of lymphocyte proliferation by PLA2, was parallel to the change of percentage of helper T cells. Furthermore--a CD4-rich population was proved more susceptible to PLA2 effect than a CD8-rich population. Para-bromophenacyl bromide (pBPB), an irreversible inhibitor of PLA2, abrogated the biphasic effect of PLA2 on PHA MNC proliferation. These results suggest that PLA2 plays a regulatory role on immune reactions by modulating the percentage of helper T cells.  相似文献   
58.
Summary Thirty-one patients with stage IIIB or IV non-small cell lung cancer (NSCLC) were treated with intravenous 10-EdAM on a weekly basis. The starting dose was 80 mg/m2, with subsequent doses adjusted depending on evidence of toxicity. There were 20 men and 11 women with a median age of 58 years (range, 33–75). Response was evaluated in 30 patients, 5 with evaluable but not measurable tumors and 25 with measurable indicator lesions. There were no complete remissions; 3 patients achieved partial remission. Nine patients had a minor response, 6 showed no change, and 12 had progressive disease. Median survival for all 31 patients was 43 weeks (range, 12–65+). During the first 3-week period, the 10-EdAM dose was reduced or withheld in 19 patients (because of stomatitis in 12, SGPT elevation in 3, skin rash in 2, and granulocytopenia in 2), escalated in 11 patients, and unchanged in 1 patient. A mean of 34–88 mg/m2of 10-EdAM (median, 50) was given per week during the first 5-week period. Myelotoxicity was infrequent and there was no significant nephrotoxicity. Considering the modest side effects of this treatment and the conservative dose-modification schedule which mandated substantial dose reductions, we conclude that 10-EdAM is a promising antitumor agent for NSCLC.  相似文献   
59.
应用我室建立的化学发光自显影技术检测鸭沙门氏菌。用酶标抗体与硝酸纤维素膜上固定的细菌结合,再同发光底物溶液作用,使X线胶片感光,根据胶片上的黑斑进行半定量,可检出100个菌。其检测特异性好,约2小时即可出报告。  相似文献   
60.
In an attempt to develop a new anticancer platinum complex with greater or equivalent antitumor activity but reduced side effects compared with cisplatin (CDDP), a series of new platinum complexes having a glycolate leaving ligand was synthesized. Among them, five complexes were selected for further development on the basis of adequate water solubility, low nephrotoxicity and high antitumor activity in a murine system. The chemosensitivity of these five complexes was examined in MTT assay against two human pulmonary adenocarcinoma cell lines, PC-9 and PC-14, and two human stomach adenocarcinoma cell lines, MKN-45 and KATO III. Their IC50 and relative antitumor activity (RAA) values were compared with those of CDDP and 254-S, a second-generation platinum complex with a glycolate leaving ligand under phase III clinical trial. The lowest mean IC50 value was observed in CDDP, followed by SKI 2034R and SKI 2033R. In this study, the antitumor activity was evaluated in terms of RAA values and SKI 2034R showed the highest RAA value. The order of RAA values was SKI 2034R > CDDP > SKI 2032R > SKI 2033R > SKI 2030R > SKI 2029R > 254-S. Based on the RAA order, we have recommended SKI 2034R as the most promising candidate for further development of a clinically useful platinum complex.  相似文献   
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