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无环鸟苷亲脂性前体药物脂质体的制备及体外抗病毒活性(英文) 总被引:2,自引:0,他引:2
本文通过将无环鸟苷(acyclovir,简称ACV)2’位羟基分别与月桂酰氯或棕榈酰氯进行酯化反应,制得亲脂性前体药物无环鸟苷月桂酸酯和无环鸟苷棕榈酸酯(分别简称为C12-ACV和C16-ACV),使脂质体包封率从ACV的29.9%提高到C12-ACV的95.6%和C16-ACV的97.1%;漏泄实验表明在4℃透析60h后,一半以上的ACV从脂质体中漏泄,而C12-ACV和C16-ACV的滞留率分别为70%和80%;体外抗疱疹病毒的试验中,在最低试验浓度0.044μmol/L时,ACV不显示抗病毒活性,而C16-ACV脂质体抑制细胞病变率达75%,说明前体药物通过与脂质体脂膜的结合增加了药物的进入细胞能力,从而提高了ACV的抗病毒能力。 相似文献
3.
Development of hatching blastocysts from immature human oocytes following in-vitro maturation and fertilization using a co-culture system 总被引:8,自引:0,他引:8
Hwu YM; Lee RK; Chen CP; Su JT; Chen YW; Lin SP 《Human reproduction (Oxford, England)》1998,13(7):1916-1921
Recently, in-vitro maturation (IVM) of immature human oocytes recovered
from non-stimulated follicles has been applied in the treatment of
infertility. However, in previous reports, very few embryos cultured in
conventional medium have reached the expanded blastocyst stage following
in-vitro maturation and fertilization (IVM/IVF). The objective of this
study was to investigate whether the developmental competence of human
embryos following IVM/IVF could be enhanced by the use of a human ampullary
cell co-culture system. Immature human oocytes were aspirated from small
follicles at Caesarean section and then cultured in medium containing human
menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes
were randomly cultured either in conventional culture medium alone or in
the co-culture system. Of 48 embryos cultured in conventional medium alone,
all arrested at the 2-16- cell stage on day 3 after insemination. Of 46
embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at
the 2-16-cell stage. Six embryos (13%) developed to the morula stage.
Fourteen embryos (30.4%) developed to expanded blastocysts and two
blastocysts were hatching on day 7 after insemination. We conclude that
co-culture significantly enhances the development of blastocysts in embryos
resulting from IVM/IVF.
相似文献
4.
Power spectral analysis of the electroencephalographic and hemodynamic correlates of propofol anesthesia in the rat: Intravenous infusion 总被引:2,自引:0,他引:2
Peter P. C. Tan Ming-Hwang Shyr Chen-Hsein Yang Terry B. J. Kuo Wynn H. T. Pan Samuel H. H. Chan 《Neuroscience letters》1993,160(2):205-208
Based on the tail-flick response to noxious thermal stimuli, we determined in the present study that effective antinociception could be achieved in adult male Sprague-Dawley rats 15 min after intravenous infusion of propofol at 60 mg/kg/h. Simultaneous power spectral analysis of the electroencephalographic (EEG) and systemic arterial pressure signals further revealed a concomitant depression of the activity of all EEG frequency bands (δ, θ, , β), alongside hypotension, negative inotropic and chronotropic actions, and attenuated baroreceptor reflex and vasomotor activity. These effects were congruent with a plasma concentration of propofol in the arterial blood of 1.70 ± 0.13 μg/ml, as determined by high-performance liquid chromatography. 相似文献
5.
Comparison of different PCR approaches for characterization of Burkholderia (Pseudomonas) cepacia isolates. 总被引:1,自引:2,他引:1 下载免费PDF全文
P Y Liu Z Y Shi Y J Lau B S Hu J M Shyr W S Tsai Y H Lin C Y Tseng 《Journal of clinical microbiology》1995,33(12):3304-3307
In this study, we evaluated three PCR methods for epidemiological typing of Burkholderia (Pseudomonas) cepacia--PCR-ribotyping, arbitrarily primed PCR (AP-PCR) and enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR)--and compared them with pulsed-field gel electrophoresis. The analysis was performed with 31 isolates of B. cepacia, comprising 23 epidemiologically unrelated isolates and 8 isolates collected from the same patient during two episodes of bacteremia. Pulsed-field gel electrophoresis, ERIC-PCR, and AP-PCR identified 23 distinct types among the 23 unrelated isolates, while PCR-ribotyping only identified 12 strain types, even after AluI digestion of the amplification products. Among the eight isolates collected from the same patient, all typing techniques revealed two clones of strains. The day-to-day reproducibilities of PCR-ribotyping and ERIC-PCR were good, while greater day-to-day variations were noted in the fingerprints obtained by AP-PCR. We conclude that all three PCR techniques are useful for rapid epidemiological typing of B. cepacia, but ERIC-PCR seems to be more reproducible and discriminative. 相似文献
6.
Helicobacter pylori genotypes, host factors, and gastric mucosal histopathology in peptic ulcer disease 总被引:10,自引:0,他引:10
Tham KT Peek RM Atherton JC Cover TL Perez-Perez GI Shyr Y Blaser MJ 《Human pathology》2001,32(3):264-273
From 183 patients undergoing upper gastrointestinal endoscopy, we used antral and corpus gastric biopsies for bacterial culture and histopathologic examination, blood samples to detect immunoglobulin G antibodies against Helicobacter pylori, and H pylori genomic DNA to analyze cytotoxin-associated gene A (cagA) and vacuolating cytotoxin (vacA) genotypes. As expected, among H pylori biopsy-positive patients, those with duodenal ulcer (DU) (n = 34) had significantly more severe chronic and acute inflammation (P <.001) and epithelial degeneration (P =.004) in the gastric antrum than in the gastric corpus. Each of those 3 parameters and H pylori density were significantly higher in the antrum of patients with DU than in patients with gastric ulcer (GU) or no ulcer. Colonization with vacA s1/cagA-positive strains of H pylori was associated with inflammation and epithelial degeneration in gastric mucosa and increased risk for peptic ulcer disease (PUD), whereas colonization with vacA s2m2/cagA-negative strains was associated with mild gastric histopathology and was not associated with any significant risk for PUD. The predominant H pylori strains in African Americans were vacA s1bm1/cagA-positive, whereas all genotypes were well represented in non-Hispanic-Caucasians. By multivariate analysis, H pylori colonization was significantly associated with DU (Adjusted odds ratio [AdjOR] = 3.2 [1.4-7.2]) and nonsteroidal anti-inflammatory drugs (NSAID) use was inversely associated (AdjOR = 0.3 [0.2-0.7]). NSAID use (AdjOR = 4.3 [1.02-18.5]) and African-American ethnicity (AdjOR = 10.9 [2.6-50]) were significantly associated with GU. Smoking and age were not significantly associated with either DU or GU. These data indicate that DU is associated with an antral-dominant gastritis, and H pylori genotype and NSAID use independently contribute to the pathogenesis of PUD. HUM PATHOL 32:264-273. This is a US Government work. There are no restrictions on its use. 相似文献
7.
BackgroundThere are no reports of performing mesopancreas dissections in robotic pancreaticoduodenectomy. This study evaluated the feasibility and justification for mesopancreas level 3 dissection in robotic pancreaticoduodenectomy.MethodsSurgical outcomes after robotic pancreaticoduodenectomy and open pancreaticoduodenectomy were evaluated and compared.ResultsThere were 289 robotic pancreaticoduodenectomy and 162 open pancreaticoduodenectomy patients included in the study. Postoperative diarrhea occurred in 34.5% of mesopancreas level 3 dissection cases and was higher than in levels 2 and 1 dissection cases, P < .001. Blood loss in the robotic pancreaticoduodenectomy group was higher for mesopancreas level 3 dissection, with a median loss of 263 mL (P = .015). The rate of R0 resection with margin >1 mm was higher for mesopancreas level 3 dissection (93.8%) than for level 2 dissection (72.2%) (P < .001). The lymph node yield was higher for mesopancreas level 3 dissection in robotic pancreaticoduodenectomy; the median lymph node yield was 21 for level 3, 18 for level 2, and 14 for level 1 (P < .001). Compared with mesopancreas levels 1 and 2 dissections in the robotic pancreaticoduodenectomy groups, level 3 dissection did not show increased surgical mortality or postoperative complications, including postoperative pancreatic fistula, delayed gastric emptying, postpancreatectomy hemorrhage, chyle leakage, bile leakage, or wound infection. Compared with open pancreaticoduodenectomy, mesopancreas level 3 dissection in robotic pancreaticoduodenectomy had less blood loss, no delayed gastric emptying, and lower chyle leakage.ConclusionMesopancreas level 3 dissection in robotic pancreaticoduodenectomy is feasible without compromising surgical safety. Therefore, robotic pancreaticoduodenectomy can be recommended as a safe alternative to open pancreaticoduodenectomy for mesopancreas level 3 dissection. 相似文献
8.
Relationship between HLA-DRB1 and DQ alleles and the genetic susceptibility to type 1 diabetes 总被引:6,自引:0,他引:6
Objective To study the relationship between human leukocyte antigen (HLA)-DRB1 and DQ alleles and the genetic susceptibility of type 1 diabetes in North Chinese children. Methods Polymerase chain reaction (PCR) techniques were used to amplify the second exon of DRB1 and DQ alleles, after which sequence specific olignucleotide probe (SSOP) dot blot hybridization techniques were used to analyze the amplified products. Results DRB1*0301, DQA1*0301, DQB1*0201 alleles and DRB1*0301-DQA1*0501-DQB1*0201 haplotype were significantly increased in patients, while DQA1*0103 and DQB1*0601 alleles were significantly increased in controls. The distribution of DR4 and DR9 haplotypes in patients and controls were not significantly different, but DR3/DR4 and DR4/DR9 heterozygotes were significantly increased in patients. Conclusions DRB1*0301, DQA1*0301 and DQB1*0201 confer susceptibility while DQA1*0103 and DQB1*0601 confer protection to type 1 diabetes. DRB1*0301-DQA1*0501-DQB1*0201 haplotype offers a predisposition to type 1 diabetes in North Chinese. Although the distribution of DR4 and DR9 in patients and controls had no significant difference, DR3/DR4 and DR3/DR9 heterozygotes were significantly increased in patients, showing that the susceptive effects of DR3 and DR4 or DR4 and DR9 haplotypes could be added up. 相似文献
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10.
0 引言 人类免疫缺陷病毒 (human immunodeficiencyvirus,HIV) - 1编码的反式激活蛋白 TAT具有独特的跨膜运转方式 ,而且有转导速度快 ,效率高的特点 ,被称为蛋白转导结构域 (protein transduction domain,PTD) [1 ,2 ] .本研究用PCR扩增了慢性粒细胞白血病慢粒 bcr/ abl融合蛋白的基因片段 ,在其 5′端融合 PTD结构域的编码区后在大肠杆菌中进行了表达 .表达产物经纯化后 ,加入培养的 HL 6 0细胞 ,表达的蛋白可直接进入细胞内 .这一结果为用外源蛋白负载(L oading)免疫细胞提供了新的途径 .1 材料和方法1.1 DNA重组 人工合… 相似文献