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141.
重组人生长激素对体外人结肠癌COLO-320细胞生长的影响   总被引:2,自引:0,他引:2  
目的 探讨重组人生长激素 (rhGH)对体外人结肠癌COLO 3 2 0细胞生长的影响。方法 取对数生长期的人结肠癌细胞株COLO 3 2 0细胞 ,分别在有血清 (血清组 )和无血清 (无血清组 )条件下培养 ,以不同浓度的rhGH和(或 )羟基喜树碱 (CPT)培养COLO 3 2 0细胞 ,分别培养 2 4h、48h及 72h ,然后用四甲基偶氮唑蓝 (MTT)法测定结肠癌细胞生长抑制率。结果 不同浓度的rhGH作用不同时间对人结肠癌细胞株COLO 3 2 0细胞的生长均无明显影响 (P>0 .0 5 ) ;单用CPT或rhGH联合CPT使用时对该细胞生长的抑制率均明显高于单用rhGH(P<0 .0 1) ,但前两者间差异无统计学意义 (P>0 .0 5 )。结论 体外条件下rhGH对人结肠癌细胞株COLO 3 2 0细胞的生长既无促进作用 ,也无抑制作用 ,且不影响CPT对人结肠癌细胞株COLO 3 2 0细胞的抑制作用。  相似文献   
142.
In primates, corpus luteum development involves both gonadotrophin stimulation and exposure to low density lipoprotein (LDL) delivered through vascularization of the granulosa cell-derived layer. These regulatory influences were modelled in vitro using granulosa cells obtained during in-vitro fertilization (IVF) cycles controlled with gonadotrophin releasing hormone (GnRH) analogue, human menopausal gonadotrophin (HMG) and human chorionic gonadotrophin (HCG). Granulosa cells were cultured in defined medium on extracellular matrix. Without gonadotrophin or LDL in the medium, progesterone production declined progressively. With LDL alone, there was a short-lived elevation of progesterone output which subsequently declined. Culture with HCG alone resulted in a relatively unchanged rate of steroid production over 5 days despite morphological development. This contrasted with a marked and sustained increase in progesterone output over the same time when granulosa cells were cultured with combined HCG/LDL. Cultures were challenged with combined HCG/LDL on day 5. Where initial incubation included HCG, the challenge resulted in a recovery of progesterone output to values comparable to those of granulosa cells exposed to continuous HCG/LDL. Initial incubation without gonadotrophin led to a reduced response. Results suggest that LDL delivery to granulosa cells of the early corpus luteum causes a short-lived period of progesterone production. Sustained luteinization of granulosa cells and maintenance of gonadotrophin responsiveness requires continued exposure to gonadotrophin in the luteal phase.  相似文献   
143.
During bone development and repair, angiogenesis, osteogenesis, and bone remodeling are closely associated processes that share some common mediators. In the present study nonadherent human bone marrow mononuclear cells under the induction of sRANKL and M-CSF, differentiated into osteoclasts with TRAP-positive staining, VNR expression, and Ca-P resorptive activity. The effects of various combinations of rhBMP-2 (0, 3, 30, and 300 ng/mL) and rhVEGF (0 and 25 ng/mL) on osteoclastogenesis potentials were examined in this experimental system. The percentages of TRAP-positive multiple nucleated cells represent osteoclast differentiation potential, and the percentages of resorptive areas in the Ca-P coated plates resemble osteoclast resorption capability. The presence of rhBMP-2 at 30 and 300 ng/mL showed inhibitory effects on osteoclast differentiation and their resorptive capability in the human osteoclast culture system. rhVEGF (25 ng/mL) enhanced the resorptive function of osteoclast whenever it was used alone or combined with 3 ng/mL rhBMP-2. However, rhVEGF-induced resorptive function was inhibited by 30 ng/mL and 300 ng/mL rhBMP-2 in a dose-dependent manner. Statistical analysis demonstrated that an interactive effect exists between rhBMP-2 and rhVEGF on human osteoclastogenesis. These findings suggested that an interactive regulation may exist between BMPs and VEGF signaling pathways during osteoclastogenesis; exact mechanisms are yet to be elucidated.  相似文献   
144.
1. The pharmacokinetics of Dalal-peptide T-NH2 (peptide T) was determined during phase I clinical trials in patients with acquired immunodeficiecy disease (AIDS) and AIDS related complex (ARC). Drug levels were determined by specific RIA, and in some cases with HPLC analysis, after intraveneous (i.v.) or intranasal (i.n.), via metered sprayer, administration.

2. The plasma kinetics appeared to be bi-phasic with a first compartment half-life of 30 to 60 minutes and a second plasma clearence rate of 4 to 6 hours, observed for both routes of administration. Peptide T, in one individual was confirmed to be present at 6 hrs in plasma, determined after HPLC isolation followed by specific RIA.

3. Bioavailabilty, determined for a 2 mg test dose in six individuals was 9.3 ± 6.9 nmol/L. Peak plasma levels of 41 ± 30 nmol/L after 10 mg i.n., 2.8 ± 5.9 nmol/L after 2mg i.n., and 0.13 ± 0.07 nmol/L after 0.4 mg i.n. were observed. In two individuals tested, peptide T was detected in CSF at levels 20% of the corresponding plasma level 90 and 145 minutes post i.v. administration. Peptide T was not detected in urine. I.N. administration was well tolerated for times up to 21 months.  相似文献   

145.
To clarify the prevalence of concurrent infection with hepatitis C virus (HCV), hepatitis B virus (HBV) and human T cell leukaemia virus (HTLV), we measured HCV antibody in the population of a district endemic for HBV and HTLV infection. Blood samples were collected in June 1990 from 579 inhabitants of four islands of Uwa Bay in the southwest of Ehime Prefecture in Japan. Anti-HCV antibody against C100-3 protein was detected using an enzyme-linked immunosorbent assay kit (Ortho Diagnostics). Thirteen of the 579 inhabitants (2.2%) were positive for anti-HCV, and this prevalence rate was not significantly different from the frequency of anti-HCV in Tokyo blood donors. A total of 11% (64 of 579) of the subjects were positive for HBsAg and 3.3% (19 of 579) were positive for anti-HTLV. These frequencies of HBsAg and anti-HTLV positivity were distinctly higher than the respective means of Japanese. All anti-HCV positive individuals were negative for HBsAg and anti-HTLV, while 54% (7 of 13) had increased alanine aminotransferase levels. These data suggest that the prevalence of HCV infection is not high even in an area endemic for HBV and HTLV infection.  相似文献   
146.
A new two-step deprotection/cleavage procedure for t-butoxycarbonyl (Boc) based solid phase peptide synthesis is reported. First the protective groups are removed from 4-(oxymethyl)-phenylacetamidomethyl (PAM) resin attached peptide with the weak hard acid, trimethylsilyl bromide-thioanisole/trifluoroacetic acid (TFA). In the second step, the peptide is cleaved from the resin with a stronger hard acid such as trimethylsilvl trifluoromethanesulfonate in TFA or with HF. The method is also shown to deformylate Nin-formyltryptophan moiety efficiently. The usefulness of this procedure for practical solid phase peptide synthesis is demonstrated by comparison with other deprotection methods in the synthesis of urotensin II and human endothelin.  相似文献   
147.
Recurrence of hepatitis C (HCV) following liver transplantation is common. Herpesvirus reactivation following transplant may have an immunomodulatory effect resulting in increased HCV replication. We studied whether cytomegalovirus (CMV) and human herpesvirus-6 (HHV-6) may be associated with HCV recurrence and viral load after transplant. We prospectively followed 66 HCV liver-transplant recipients with serial viral load testing for CMV and HHV-6. Infection and viral load were correlated with the development of biopsy-proven HCV recurrence and HCV viral loads. Histologic recurrence of HCV occurred in 41/66 (62.1%) patients. In the primary analysis, CMV infection and disease, and HHV-6 infection were not associated with HCV recurrence. Peak CMV and HHV-6 viral loads were not significantly different in patients with and without recurrence. No correlation was observed between HCV viral loads at 1 and 3 months post-transplant and peak HHV-6 or CMV viral loads. In a subgroup analysis, HHV-6 infection was associated with the development of more severe recurrence (hepatitis and/or fibrosis score > or = 2) (p = 0.01). Also, fibrosis scores at last follow up were higher in patients with CMV disease (1.67 vs. 0.56; p = 0.016) and in patients with HHV-6 infection (1.18 vs. 0.55; p = 0.031). In conclusion, HHV-6 and CMV infection and viral load were not associated with increased overall rates of HCV recurrence or HCV viral load after liver transplantation but may be associated with more severe forms of recurrence.  相似文献   
148.
有性生殖物种的单亲繁殖   总被引:1,自引:1,他引:0  
生物科技的进步,如转基因技术与细胞核转移技术,不但改变了生物学与医药学的研究模式,更加深了和革新着我们对人类自身生物学特性的认识。通过定义线粒体DNA为转基因,我们曾提出核化线粒体组学与转基因人的新概念。鉴于有关克隆人的技术安全性与伦理学的争论。探讨了是否存在天然克隆人的可能性及检验这一可能性的相关研究途径;同时还探讨了单亲繁殖在遗传诊断中可能具有的指导作用。  相似文献   
149.
Resistance to change in monitoring practices from within the anaesthesiology community is a formidable obstacle, and coercive and exhortatory solutions are likely to be unsuccessful in some situations. An analysis of publications about technology transfer and professional obsolescence, and application of this data to the practice of anaesthesia, reveals various stresses that technology transfer from research areas to the workplace may induce in vulnerable anaesthesiologists and account for their attitudes. It is suggested that the invaluable pronouncements of high profile anaesthesiologist groups must be supplemented by supportive behaviour by physicians and administrators at an institutional level. The human factors issues to be addressed include: (i) Monitored data acquisition skills. (ii) Possibility of acting on monitored data. (iii) Assistance for personal insight into attitudinal difficulties that may be encountered. (iv) Data supporting the value of the device. (v) Ergonomically effective integration of the monitor into the work station.Alternatively the perceptions of potential users may accurately reflect changes in their status in the new work situation created by monitors, and decision making aids that may or may not be derived from them. Thus, plans to present job satisfaction in related clinical areas or to associate the proposed new system with evaluation of its effect on patient outcome will be necessary. In this way the clinician becomes involved in clinical research, a quality of personal and quality care development.  相似文献   
150.
重组人生长激素在重型颅脑损伤中的应用   总被引:4,自引:0,他引:4  
目的探讨重组的人生长激素(rhGH)在重型颅脑损伤患者中的应用价值。方法46例重型颅脑损伤患者在肠内、肠外营养支持的基础上分成rhGH组与对照组,rhGH组伤后第7天每日皮下注射思增8IU,共10d。应用后第7、14日检测血清总蛋白、白蛋白、转铁蛋白及前白蛋白。结果rhGH组(n=20)第14天血清总蛋白、白蛋白、转铁蛋白及前白蛋白浓度高于对照组(n=26)(P<0.05)。结论重型颅脑损伤患者应用rhGH能改善机体对营养底物的利用率,促进蛋白合成、减轻重型颅脑损伤后低蛋白血症。  相似文献   
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