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91.
RP-HPLC法测普鲁托品在大鼠体内分布和排泄 总被引:3,自引:0,他引:3
目的 用反相高效液相色谱法 (RP HPLC)测定大鼠的尿、粪、肝和脑等组织中普鲁托品 (protopine ,Pro)的药物浓度 ,并对Pro在大鼠体内的分布和排泄过程进行研究。方法 流动相为甲醇、水和体积分数 2 0mol·L- 1 乙酸 (80∶2 0∶2 ) ,以ODS C1 8柱分离 ,紫外检测器检测 ,波长为 2 85nm ,生物样品在碱性条件下 ,经两次乙醚处理 ,可获得良好的分离效果。为全面了解Pro在大鼠体内的代谢过程 ,给大鼠尾静脉注射Pro 1 0mg·kg- 1 后 ,测定不同时间各组织中Pro的含量。结果 静脉给药后 ,Pro快速分布到肺、肾、脾、脑、小肠、心脏、脂肪、睾丸、肝脏、胃壁及骨骼肌、以肺、肾、脾、脑、肠组织中药物浓度较高 ,尤以肺组织浓度最高。药后 3h各组织中药物浓度下降 ,但睾丸中仍维持较高浓度。实验还发现 ,药后 5min即可测得尿中有原形药 ,1 2h尿中累积排泄量为给药量的 30 .2 1 % ,48h尿中累积排泄量为给药量的 36 87%。原形药经胆汁及粪排泄量不足 1 %。药后 5min及 1 5min血浆蛋白结合率均低于 5 %。结论 普鲁托品在大鼠体内广泛分布 ,部分经尿排泄 ,血浆蛋白结合率低 相似文献
92.
The anatomic relation among the nerve roots, intervertebral foramina, and intervertebral discs of the cervical spine 总被引:18,自引:0,他引:18
STUDY DESIGN: An anatomic study of the cervical intervertebral foramina, nerve roots, and intradural rootlets performed using a surgical microscope. OBJECTIVES: To investigate the anatomy of cervical root compression, and to obtain the anatomic findings related to cervical foraminotomy for the treatment of cervical radiculopathy. SUMMARY OF BACKGROUND DATA: Cervical foraminotomy is a procedure performed frequently for the management of cervical radiculopathy. However, anatomic studies of cervical foraminotomy have not been fully elucidated. METHODS: In this study, 18 cadavers were obtained for the study of the cervical spine. All the soft tissues were dissected from the cervical spine. Thereafter, laminectomy and facetectomy were performed on C4 through T1 using a surgical microscope. The nerve roots and surrounding anatomic structures, including intervertebral discs and foramina, were exposed. In addition, the intradural rootlets and their intersegmental connections were observed. RESULTS: The shape of the intervertebral foramina approximated a funnel, the entrance zone being the most narrow part and the root sleeves conical, with their takeoff points from the central dural sac being the largest part. Therefore, compression of the nerve roots occurred at the entrance zone of the intervertebral foramina. Anteriorly, compression of the nerve roots was caused by protruding discs and osteophytes of the uncovertebral region, whereas the superior articular process, the ligamentum flavum, and the periradicular fibrous tissues affected the nerve posteriorly. The C5 nerve roots were found to exit over the middle aspect of the intervertebral disc, whereas the C6 and C7 nerve roots were found to traverse the proximal part of the disc. The C8 nerve roots had little overlap with the C7-T1 disc in the intervertebral foramen. The C6 and C7 rootlets passed two disc levels in the dural sac. Also, a high incidence of the intradural connections between the dorsal rootlets of C5, C6, and C7 segments was found. CONCLUSIONS: This study demonstrated the anatomy of the nerve roots, rootlets, and intervertebral foramina, and may aid in understanding the pathology of cervical radiculopathy. The presence of intradural connections between dorsal nerve roots and the relation between the course of the nerve root and the intervertebral disc may explain the clinical variation of symptoms resulting from-nerve root compression in the cervical spine. To perform cervical foraminotomy for cervical radiculopathy, it is necessary to understand the detailed anatomy of the intervertebral foramina thoroughly. 相似文献
93.
94.
Antitumor effects of bortezomib (PS-341) on primary effusion lymphomas. 总被引:16,自引:0,他引:16
Primary effusion lymphomas (PELs) are a rare type of non-Hodgkin's lymphoma that are resistant to cytotoxic chemotherapy. PELs manifest constitutive activation of nuclear factor kappa B (NF-kappaB), and inhibition of NF-kappaB induces apoptosis of PELs and sensitizes to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced death. Bortezomib (PS-341), a peptidyl boronic acid inhibitor of the proteasome, is a potent agent against a wide range of hematologic malignancies and has been shown to inhibit NF-kappaB. Thus, we examined the cytotoxic effects of bortezomib alone and in combination with various drugs. Bortezomib potently inhibited NF-kappaB in PEL cells in a dose-dependent manner. In addition, bortezomib inhibited growth and induced apoptosis of PEL cell lines (IC(50) values of 3.4-5.0 nM). Results of drug interactions between bortezomib and chemotherapy (doxorubicin and Taxol) were schedule-dependent: synergistic interactions were generally observed when PEL cells were pretreated with bortezomib prior to chemotherapy, whereas additive or even antagonistic interactions occurred with chemotherapy pretreatment or simultaneous treatment with bortezomib and chemotherapy. Most schedules of bortezomib and dexamethasone were synergistic, although pretreatment with dexamethasone resulted in additive interactions. Effects of combinations of bortezomib and TRAIL were generally additive. Thus, bortezomib represents a promising potential therapy for the treatment of PEL. 相似文献
95.
Thl Bias in PBMC Induced by Large Scale Auto-CIK Infusion in Malignant Solid Tumor Patients in China
OBJECTIVE This article is to verify feasibility and validity of autologous cytokine-induced killer cell (Auto-CIK) treatment in solid malignancypatients.METHODS Amplification, phenotypic characteristics, cytokine secretion,antitumor cytotoxicity and clinical response to Auto-CIK derived from 65cases of solid tumor patients with different pathological types and clinicalstages were compared with LAKs in a large-scale clinical trial,RESUL‘r$ We found that seriousness of disease and metastatic status hadno influence on effective components and antitumor immunological activityof Auto-ClK. Comparing cytotoxicity against various tumor cells with LAKsat various effector to target ratios, ClKs showed more effective cytotoxicityagainst NK sensitive or non-sensitive solid tumor cell lines at a low E/T ratio(6:1) which suggests indirectly that Auto-CIK had a longer effective time invivo than LAKs. These results suggest that CIKs are more suitable forimmunotherapy for those solid malignancy patients at high risk of relapse orrecurrence.CONCLUSIONS Our experimental data were consistent ~ith the reportedconclusion that the potent antitumor activity of Auto-ClK mainly rooted in theCD4- part of CIKs, including CD3~CD56~ cells and CD8 ~ CTLs. The CD4~part of ClKs seemed to have no direct tumor lytic activity. The results indicatethat the special “Thl bias“ and enhanced cytotoxicity against K562 cellsoccurred in PBMCs after multicycles of Auto-ClK infusions suggesting theinduction of a “Thl shift“ and rectification of “Th2 dominance“ in PBMC afterAuto-CIK treatments. 相似文献
96.
腰椎间盘退变动物模型的建立 总被引:5,自引:0,他引:5
目的 建立腰椎间盘退变的动物模型并行组织学和MRI观察。 方法 健康成年恒河猴 8只 ,手术组 6只 ,在其腰4 ,5、腰5,6、腰6,7椎间盘分别作一 5mm× 3mm切口 ,分别于术前及术后 1、4、8、13、2 0周对手术椎间盘行MRI观察 ;8只恒河猴分别于术前 (对照组 )及术后 4、8、2 0周随机取 2只处死后行椎间盘组织学观察。 结果 正常成年恒河猴腰椎间盘组织学结构特点与人类相似 ;手术椎间盘高信号区域面积的百分比于术后 8、13、2 0周显著减少 (P <0 0 5 ) ;术后 4周椎间盘切口外被纤维组织覆盖 ,术后 8周 ,切口外层纤维样愈合 ,其内无愈合迹象 ,术后 2 0周 ,切口向椎间盘内延伸 ,部分髓核出现纤维化。 结论 恒河猴是一种生理特性与人类相接近的动物 ,以其为对象应用纤维环切开法可以获得可靠的腰椎间盘退变动物模型 ;通过测量MRI轴位T2加权像椎间盘高信号区域面积百分比的方法可于早期无损伤地发现椎间盘退变。 相似文献
97.
目的:探索宁夏枸杞采收、制于规律,指导宁夏枸杞采收制干SOP的制定。方法:总结归纳宁夏枸杞采收制干现状,分析采收时间和间隔期以及制干方法对宁夏枸杞品质质量和产量的相关影响。结果与结论:正确掌握采收的最佳时机和适宜的制干方法是影响宁夏枸杞品质质量和产量的关键因素,科学合理制定宁夏枸杞采收制干SOP。 相似文献
98.
Liliana Ala Andrade Renato Z Torres An José Fs Sales Regina Vicentini Gustavo A De Souza 《Pathology oncology research : POR》1998,4(1):44-47
Three cases of intravenous leiomyomatosis (IVL) of the uterus, a rare benign smooth-muscle tumor, are described. A preoperative
diagnosis of IVL was not made in any of the patients, all of which presented with a pelvic mass with the presumptive diagnosis
of leiomyoma. Surgical exploration confirmed the presence of uterine mass and two of the three cases showed extra-uterine
extension into the ovarian or uterine veins. Histological examination demonstrated a fascicular pattern of bland spindle-shaped
smooth-muscle cells, which extended to veins inside the myometrium or to extrauterine veins. This was confirmed by immunohistochemical
stain for desmin and factor VIII. Despite their histological benignity, these lesions have a tendency to metastasize and are
closely related to the conditions called “benign metastasizing leiomyoma” and “intracaval mass and cardiac extension”. The
primary treatment of IVL is hysterectomy and excision of any extrauterine tumor, when technically feasible. Anti-estrogenic
therapy has been suggested as potentially useful in controlling of unresectable tumor. According to the literature, the follow-up
must be long and periodic postoperative ultrasonic or magnetic nuclear resonance imaging studies may be useful in detecting
growth of residual intravascular tumor. 相似文献
99.
目的微卫星(microsatellite)是广泛分布于生物基因组中的DNA重复序列,与许多重要基因紧密连锁。本研究旨在探讨食管癌变多阶段演进过程中微卫星DNA杂合缺失(loss of heterozygosity,LOH)的特征及其意义。方法采用微卫星DNA多态分析法,选取染色体3p、5q、6p、9p、13q、17p、17q和18q的15个多态微卫星位点,对32例食管癌前病变和癌组织进行LOH分析。结果食管各级癌前病变组织和癌组织均出现不同程度的微卫星DNALOH,其频率随病变程度加重而明显升高(除D9S1752位点外,P均〈0.05);其中D9S171、D13S260和TP53位点在癌阶段,LOH频率均超过60%。各级癌前病变组织和癌组织中发生LOH的位点不尽相同,同一个体从基底细胞过度增生→间变→原位癌→鳞状细胞癌,均发生LOH的位点是:D3S1234和TP53。结论基因水平的改变发生在食管癌变的早期阶段,随病变程度加重,基因组不稳定性增强,可能是导致食管癌前病变持续向癌的方向发展的重要机制之一。 相似文献
100.
抑制性消减杂交技术检测反式二羟环氧苯并芘转化细胞与正常细胞基因表达差异 总被引:1,自引:0,他引:1
目的 筛选 7,8 二羟 9,10 环氧苯并芘 (BPDE)转化细胞与正常细胞的基因表达差异。方法 以BPDE转化支气管上皮细胞 (16HBE)细胞为检测子 (tester) ,正常 16HBE细胞为驱动子 (driver) ,应用抑制性消减杂交方法构建cDNA消减文库 ,经 2次消减杂交和 2次PCR后 ,将巢式PCR产物插入TA载体克隆 ,随机挑选克隆进行鉴定和测序 ,并用斑点杂交法验证其同源性 ,将所得序列进行GenBank的BLAST分析。结果 发现了 7个在BPDE转化细胞中高表达的基因 ,为翻译延长因子 1α1、线粒体基因、溶解物载体家族 2 5、EphA2、酪氨酸 3 加单氧酶 色氨酸 - 5 -加单氧酶活化蛋白、乳酸脱氢酶A、TRIM2 8等 ,尚有一条在GenBank的已知基因中找不到对应序列 ,在EST序列中找到全长对应序列。结论 发现的高表达基因可能在BPDE的致癌机制中起作用 ,另外 ,可能有未知基因与BPDE的恶性转化作用有关。 相似文献