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排序方式: 共有553条查询结果,搜索用时 15 毫秒
1.
目的探讨三康胶囊对高原人体运动后一氧化氮(NO)及其合酶(NOS)、乳酸(BLA)、血氨(Ammo)的影响.方法选择进驻海拔3 700 m高原1年的10名健康青年,口服三康胶囊15 d,在服药前后分别采用功量自行车进行渐增负荷运动,测定其血清 NO、NOS、BLA及Ammo含量.结果服药后较服药前运动后NO水平[(101.02±6.49) Vs (77.10±8.11)]和NOS活性[(71.40±7.23) Vs (56.29±6.28)]均增高, BLA[(7.58±0.79)Vs (6.13±0.74)]和Ammo[(80.11±9.44)Vs (69.38±8.86)]降低,有非常显著性差异(P<0.01).结论 三康胶囊能增强高原移居者运动后NOS活性,加速乳酸清除,减缓运动疲劳的发生. 相似文献
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Inhibitory monoclonal antibody against a (myristylated) small-molecular-weight antigen from Plasmodium falciparum associated with the parasitophorous vacuole membrane. 总被引:3,自引:1,他引:3
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U A Kara D J Stenzel L T Ingram G R Bushell J A Lopez C Kidson 《Infection and immunity》1988,56(4):903-909
A small-molecular-weight antigen that occurs in asexual blood stages in synchronized cultures of Plasmodium falciparum was detected by a monoclonal antibody which inhibits parasite growth in vitro. This antigen, QF116, showed a molecular weight of 15,000 in parasite strain FCR-3K+ from The Gambia and 19,000 in strain FCQ-27 from Papua New Guinea. The protein did not show significant glycosylation by galactose or glucosamine labeling but was found to be acylated by myristic acid. By using immunogold labeling and electron microscopy, the location of the antigen could be attributed to the parasitophorous vacuole membrane and to inclusions and vesicles residing within the cytoplasm of the erythrocyte host cell. 相似文献
5.
The aim of the present study was to examine whether ischaemic episodes of less than 5 min could induce preconditioning or stunning in the isolated rat heart. Hearts were subjected to total global ischaemia of 1, 2 and 4 min followed by 10 min of reperfusion before an 18-min main ischaemic period and 30 min of reperfusion. The effects on physiology, purine metabolism and anaerobic glycolysis were compared with a control group subjected to the main ischaemia only. The brief ischaemic episodes did not produce stunning based on the recovery of left ventricular developed pressure (LVDP) and heart rate (HR) product during the first reperfusion. Preconditioning of 11–14% increased recovery of LVDP x HR during the second reperfusion was observed in the 1- and 4-min group. In the 2-min group a low repayment of flow debt during the first reperfusion was associated with a slightly reduced recovery of LVDP x HR compared to the other preconditioned groups during the second reperfusion. Only in the 4-min group was preconditioning associated with fewer breakdown products of the purine nucleotide pool (adenosine) and anaerobic glycolysis (lactate) in both tissue and effluate after the main ischaemia. Preconditioning (reflected in recovery of function) could be produced with ischaemic episodes of less than 5 min that did not produce stunning. Thus, stunning is probably not the primary cause of preconditioning. 相似文献
6.
Stenzel A Semczuk A Rózyńskal K Jakowicki J Wojcierowski J 《Pathology, research and practice》2001,197(9):597-603
To analyze the coexistence of human papilloma virus (HPV) infection and K-ras gene activation in cervical neoplasia, we investigated 31 (seven pre-invasive and 24 invasive) cervical carcinomas for "low-risk" (types 6 and 11) and "high-risk" (types 16 and 18) HPVs and K-ras point mutations using PCR-based technology. "Low-risk" HPVs were not detected in the group investigated; however, 20 of 31 (64%) cases were HPV 16 positive, while HPV 18 was found in only three (9.7%) samples (HPV 6/11 v. HPV 16/18, p < 0.0001; HPV 16 v. HPV 18, p < 0.0001; Fisher's exact test). There was a K-ras codon 12 point mutation in two of 31 (6.4%) neoplasms, with none of the cases showing a K-ras codon 13 point mutation. Two moderately differentiated squamous carcinomas showed K-ras exon 2 gene alterations. Interestingly, none of the pre-invasive cervical carcinomas displayed K-ras gene point mutations. The mean patient age did not differ significantly in the number of HPV-positive and -negative cases. A coexistence of "high-risk" human papillomavirus DNA with K-ras gene alterations was observed in three of 31 (9.7%) neoplasms (one IIA and two IB moderately differentiated cervical carcinomas). Our results suggest that "high-risk" HPVs coexist with K-ras gene alterations in a subset of moderately differentiated carcinomas of the cervix uteri. 相似文献
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Phase II trial of gefitinib in recurrent glioblastoma. 总被引:13,自引:0,他引:13
Jeremy N Rich David A Reardon Terry Peery Jeannette M Dowell Jennifer A Quinn Kara L Penne Carol J Wikstrand Lauren B Van Duyn Janet E Dancey Roger E McLendon James C Kao Timothy T Stenzel B K Ahmed Rasheed Sandra E Tourt-Uhlig James E Herndon James J Vredenburgh John H Sampson Allan H Friedman Darell D Bigner Henry S Friedman 《Journal of clinical oncology》2004,22(1):133-142
PURPOSE: To evaluate the efficacy and tolerability of gefitinib (ZD1839, Iressa; AstraZeneca, Wilmington, DE), a novel epidermal growth factor receptor tyrosine kinase inhibitor, in patients with recurrent glioblastoma. PATIENTS AND METHODS: This was an open-label, single-center phase II trial. Fifty-seven patients with first recurrence of a glioblastoma who were previously treated with surgical resection, radiation, and usually chemotherapy underwent an open biopsy or resection at evaluation for confirmation of tumor recurrence. Each patient initially received 500 mg of gefitinib orally once daily; dose escalation to 750 mg then 1,000 mg, if a patient received enzyme-inducing antiepileptic drugs or dexamethasone, was allowed within each patient. RESULTS: Although no objective tumor responses were seen among the 53 assessable patients, only 21% of patients (11 of 53 patients) had measurable disease at treatment initiation. Seventeen percent of patients (nine of 53 patients) underwent at least six 4-week cycles, and the 6-month event-free survival (EFS) was 13% (seven of 53 patients). The median EFS time was 8.1 weeks, and the median overall survival (OS) time from treatment initiation was 39.4 weeks. Adverse events were generally mild (grade 1 or 2) and consisted mainly of skin reactions and diarrhea. Drug-related toxicities were more frequent at higher doses. Withdrawal caused by drug-related adverse events occurred in 6% of patients (three of 53 patients). Although the presence of diarrhea positively predicted favorable OS from treatment initiation, epidermal growth factor receptor expression did not correlate with either EFS or OS. CONCLUSION: Gefitinib is well tolerated and has activity in patients with recurrent glioblastoma. Further study of this agent at higher doses is warranted. 相似文献
9.
Nuckols JD Baron PW Stenzel TT Olatidoye BA Tuttle-Newhall JE Clavien PA Howell DN 《The American journal of surgical pathology》2000,24(5):733-741
Post-transplantation lymphoproliferative disease (PTLD) is a complication of solid organ transplantation that is typically of B-cell origin and associated with Epstein-Barr virus (EBV). In patients receiving orthotopic liver transplantation (OLT) and treated with cyclosporin A. PTLD typically presents between 6 and 17 months post-transplantation as a systemic illness with involvement of the hepatic graft in a minority of cases. A small number of cases of biopsy-proven PTLD arising in the hepatic graft and limited to the liver and periportal structures have been previously reported. This report describes three additional cases of liver-localized PTLD and reviews similar cases in the literature. The donor/host origin of PTLD may have prognostic significance because the two cases in this report that are of donor origin had different clinical and pathologic features compared with the case of host origin. A rapid PCR-based technique for determining the origin of PTLD is described. 相似文献
10.
Aberrant crypt focus promotion and glucose intolerance: correlation in the rat across diets differing in fat, n-3 fatty acids and energy 总被引:1,自引:0,他引:1
Koohestani N; Chia MC; Pham NA; Tran TT; Minkin S; Wolever TM; Bruce WR 《Carcinogenesis》1998,19(9):1679-1684
McKeown-Eyssen (Cancer Epidemiol. Biomarkers Prevent., 3, 687-695, 1994)
and Giovannucci (Cancer Causes Control, 6, 164-179, 1995), noting the
striking similarity in lifestyle risk factors for colorectal cancer and
insulin resistance, proposed that the hyperinsulinemia, glycemia and
hypertriglyceridemia associated with insulin resistance promotes colon
cancer. To compare the effect of diet on colon cancer promotion and insulin
resistance in the F344 rat, we assessed the effect of fat, n-3 fatty acids
and energy in pairwise comparisons on average size of aberrant crypt foci
(ACF) and on glucose intolerance in the same animals in a single
experiment. Diets high in fat and energy increased and diets with increased
n-3 fatty acids and calorie restriction decreased both ACF growth and
glucose intolerance compared with control diets. The measures of promotion
of colon cancer and insulin resistance were strongly correlated (n = 98, r
= 0.67, P < 0.001). In addition, both were highly correlated with daily
energy intake (r = 0.62 and 0.66) and were also correlated with basal
(post-prandial) insulin, glucose and triglycerides (r = 0.31-0.53, P <
0.01). We concluded that ACF growth and glucose intolerance are correlated
for a wide range of diets and that increased circulating energy (glucose
and triglycerides) may lead to both colon cancer promotion and insulin
resistance.
相似文献