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61.
62.
柴胡皂甙q及其甙元的结构鉴定 总被引:4,自引:0,他引:4
从小叶黑柴胡(Bupleurum smithii Wolffvar;parvifolium ShanetY.Li)的根中得到3个化合物,柴胡皂甙元A和Q及柴胡皂甙q。柴胡皂甙元Q和柴胡皂甙q为新化合物,根据理化性质和波谱分析,确定其结构分别为齐墩果烷-11,13(18)-二烯-3β,16β,23,28,30-五醇和3β,16β,23,28,3O-五羟基齐墩果烷-11,13(18)-二烯-3-O-β-D-吡喃葡萄糖基(1→6)-[α-L-吡喃鼠李糖基(1→4)]-β-D-吡喃葡萄糖甙。 相似文献
63.
目的:对不同个体椎骨短期精度进行观察,发现骨质疏松的严重程度不同其短期精度不同。分析DPX-MD双能X射线骨密度仪测量不同个体椎骨骨面积、骨矿含量、椎体宽、椎体高的短期精密度,了解上述指标对骨矿含量或骨密度测定的影响,以便为骨矿含量或骨密度检测质量控制和减少误差提供依据。
方法:实验于2004-05/2006-12在川北医学院人体解剖实验室与川北医学院附属医院内分泌科骨密度室完成。①对象:铝体模;3个活体椎体(38岁骨密度正常男性;40岁骨质疏松症男性;62岁轻微骨量减少女性);1个带软组织的死体椎体(由川北医学院人体解剖实验室提供)。②方法及评估:采用美国Lunar公司生产的DPX-MD双能X射线骨密度仪测量各椎体的椎骨面积、骨矿含量、椎体宽、椎体高及骨矿含量/椎体宽。3次/d,连续测定5d。铝体模和死体椎体两端均用小木块固定在6.5cm的高度,放在15cm的水浴中,为减少误差由一人操作。由不同椎骨面积、骨矿含量、椎体宽、椎体高及骨矿含量/椎体宽可得到各自的变异系数。
结果:①腰椎各椎体和L2~4的骨矿含量的变异系数:各椎体或L2~4骨矿含量变异系数从正常男性椎体、骨质疏松症男性椎体、轻微骨量减少女性椎体与死体椎体呈依次增大。②各椎体和L2~4的椎骨面积、椎体宽、椎体高的变异系数:椎骨面积、椎体宽的值从铝体模、正常男性椎体、骨质疏松症男性椎体、轻微骨量减少女性椎体与死体椎体呈依次增大,尤其是轻微骨量减少女性椎体与死体椎体较大;椎体高的变异系数以骨质疏松症男性椎体与轻微骨量减少女性椎体较大,尤其是轻微骨量减少女性椎体的变异系数最大。
结论:不同个体椎骨骨面积、骨矿含量、椎体宽、椎体高的精度不同,对骨密度测定的影响不同。椎间隙欠清楚者由于椎体分椎线难于确定,椎体高度的测定对骨密度测定影响较椎间隙清楚者大;有骨质增生和骨质疏松越严重者由于椎体边缘线难于确定,椎体宽度的测定对骨密度测定影响较无骨质增生和骨密度正常者大;有骨质增生存在和骨质疏松越严重,骨面积的测定对骨密度测定影响越大;骨质疏松越严重,骨矿含量测定对骨密度测定影响越大。 相似文献
64.
Treatment of progressive Hodgkin's disease with intensive chemoradiotherapy and autologous bone marrow transplantation 总被引:2,自引:0,他引:2
Phillips GL; Wolff SN; Herzig RH; Lazarus HM; Fay JW; Lin HS; Shina DC; Glasgow GP; Griffith RC; Lamb CW 《Blood》1989,73(8):2086-2092
Twenty-six patients with progressive Hodgkin's disease after conventional chemotherapy received intensive chemoradiotherapy and autologous bone marrow transplantation (ABMT); 19 also received additional involved-field radiotherapy. Twenty-one patients [81%, 95% confidence intervals (CI) 61% to 94%] attained complete (n = 18) or partial responses. Ten patients (38%, 95% CI 20% to 59%) are disease- free a median of 4.5 years later (range 3.5 to 7.0 years), including seven patients with continuous complete responses. The likelihood of overall response was not significantly influenced by any clinical or treatment variable examined. However, there was a trend favoring patients with higher Karnofsky scores, and higher scores were associated with attainment of complete responses (P = .06 and P = .02, respectively, Mann-Whitney U test). Both higher Karnofsky scores and shorter durations of disease before transplantation were associated with improved survival in a stepwise Cox multivariate analysis. The chief cause of failure was progression at sites previously involved with Hodgkin's disease. No patient relapsed in the marrow, and two of three patients with a history of marrow involvement with Hodgkin's disease achieved durable complete responses after transplantation. These data suggest that inadequate pretransplant conditioning, and not the reinoculation of occult tumor cells in the autologous marrow, caused most relapses. Fatal treatment-related toxicity occurred in six patients. Three patients died of idiopathic interstitial pneumonitis; each had previously received local mediastinal irradiation before intensive chemoradiotherapy. Intensive chemoradiotherapy and ABMT produces durable responses in some patients with Hodgkin's disease incurable with conventional therapy. Use of such therapies at the first sign of failure with conventional chemotherapy and development of more effective conditioning regimens should further improve results. 相似文献
65.
Braun HJ Wilcox-Fogel N Kim HJ Pouliot MA Harris AH Dragoo JL 《Knee surgery, sports traumatology, arthroscopy》2012,20(9):1689-1695
Purpose
Local anesthetic and corticosteroid combination injections are often used in clinical practice, however research investigating the chondrotoxic properties of these combinations is minimal. The goal of this study was to evaluate the effect of single injection doses of 1% lidocaine or 0.25% bupivacaine in combination with single injection doses of dexamethasone sodium phosphate (Decadron?), methylprednisolone acetate (Depo-Medrol?), betamethasone sodium phosphate and betamethasone acetate (Celestone? Soluspan?), or triamcinolone acetonide (Kenalog?) on human chondrocyte viability.Methods
All treatment conditions were delivered to human chondrocytes in vitro for the medication’s respective average duration of action using a bioreactor containing a continuous infusion pump constructed to mimic joint fluid metabolism. A two-color fluorescence assay was used to evaluate cell viability. A mixed-effects regression model was used to evaluate the mean differences in cell viability between treatment groups.Results
At 14?days, a single injection dose of 1% lidocaine or 0.25% bupivacaine in combination with betamethasone sodium phosphate and betamethasone acetate solution illustrated significant chondrotoxicity when compared with the local anesthetics alone (P?0.01). Methylprednisolone acetate and Triamcinolone acetonide both showed significant evidence of chondrotoxicity (P?=?0.013; P?=?0.016, respectively) when used in combination with 1% lidocaine compared with lidocaine alone, but showed no significant chondrotoxicity in combination with 0.25% bupivacaine (P’s?=?n.s.).Conclusions
Clinicians should use caution when injecting 1% lidocaine or 0.25% bupivacaine in conjunction with betamethasone sodium phosphate and betamethasone acetate solution due to its pronounced chondrotoxic effect in this study. 1% lidocaine used in combination with methylprednisolone acetate or triamcinolone acetonide also led to significant chondrotoxicity. 相似文献66.
Epicutaneous antigen exposure primes for experimental eosinophilic esophagitis in mice 总被引:3,自引:0,他引:3
BACKGROUND & AIMS: Eosinophilic esophagitis (EE) is frequently associated with atopic disease, including dermatitis and asthma. Data are emerging that atopic skin may provide an early entry point for antigen sensitization. We aimed to test the hypothesis that epicutaneous exposure to antigen primes for subsequent respiratory antigen-induced EE. METHODS: Wild-type and genetically engineered mice were subjected to epicutaneous antigen sensitization and the development of experimental EE, and immune responses were examined. RESULTS: We show that exposure to antigen via the epicutaneous route primes for marked eosinophilic inflammation in the esophagus triggered by a single airway antigen challenge. The development of experimental EE is associated with significant skin eosinophilia, accelerated bone marrow eosinophilopoiesis, blood eosinophilia, and large increases in serum antigen-specific immunoglobulin G1/immunoglobulin E using ovalbumin or Aspergillus fumigatus as the epicutaneous antigen. Mechanistic analysis with gene-targeted mice showed that interleukin-5 was required for esophageal eosinophilia and that interleukin-4, interleukin-13, and STAT6 contributed to a lesser extent. CONCLUSIONS: These findings provide the first evidence that epicutaneous exposure to allergens potently primes for EE via a Th2-dependent mechanism. 相似文献
67.
Shpall EJ; Stemmer SM; Hami L; Franklin WA; Shaw L; Bonner HS; Bearman SI; Peters WP; Bast RC Jr; McCulloch W 《Blood》1994,83(11):3132-3137
4-Hydroperoxycyclophosphamide (4-HC), a commonly used marrow-purging agent, is active against many tumors, but is also toxic to normal marrow progenitors. Amifostine (WR-2721) is a sulfhydryl compound with chemoprotectant activity. Preclinical studies using suspensions of bone marrow and breast cancer cells demonstrated that ex vivo treatment with amifostine followed by 4-HC resulted in protection of marrow progenitors, with no compromise in the antitumor effect of 4-HC. This fact stimulated the development of a clinical trial. Bone marrow was harvested from 15 poor-prognosis breast cancer patients and randomly assigned to ex vivo treatment with amifostine followed by 4-HC (amifostine + 4-HC), or treatment with 4-HC alone. High-dose chemotherapy was then administered followed by infusion of the purged autologous bone marrow support (ABMS). Leukocyte engraftment, defined as a white blood cell count > or = 1 x 10(9)/L, was achieved in an average of 26 days for patients whose marrow was purged with amifostine + 4-HC versus 36 days for patients whose marrow was purged with 4-HC alone (P = .032). The average number of platelet transfusions (12 v 29; P = .017) and days of antibiotic therapy (28 v 40; P = .012) were significantly less for patients whose marrow was exposed to amifostine + 4-HC, compared with 4-HC alone. Unpurged backup marrow fractions were infused into three patients whose marrow was purged with 4-HC alone, because of inadequate marrow recovery. None of the patients who received amifostine + 4-HC-purged marrow required a backup marrow fraction. Complete remissions were achieved in 83% of patients with measurable disease, with no difference between the two cohorts. Forty- three percent of patients remained alive and progression-free at a mean of 13 months posttransplant. There was no significant difference in the rate or pattern of relapse for patients whose marrow was purged with amifostine + 4-HC compared with those whose marrow was purged with 4-HC alone. Ex vivo treatment of marrow with amifostine significantly shortens the time to marrow recovery, thereby reducing the risk of myelosuppressive complications in breast cancer patients receiving high- dose chemotherapy and 4-HC-purged ABMS. Since supportive care requirements are also significantly decreased, amifostine may reduce the cost of such therapy. 相似文献
68.
Role of p21 RAS in p210 bcr-abl transformation of murine myeloid cells 总被引:11,自引:2,他引:11
Mandanas RA; Leibowitz DS; Gharehbaghi K; Tauchi T; Burgess GS; Miyazawa K; Jayaram HN; Boswell HS 《Blood》1993,82(6):1838-1847
The p21 RAS product has been implicated as part of the downstream signaling of certain nonreceptor tyrosine kinase oncogenes and several growth factor receptor-ligand interactions. We have reported that the chronic myelogenous leukemia oncogene p210 bcr-abl transforms a growth- factor-dependent myeloid cell line NFS/N1.H7 to interleukin-3 (IL-3) independence. In these p210 bcr-abl-transformed cells (H7 bcr-abl.A54) and in two other murine myeloid cell lines transformed to IL-3 independence by p210 bcr-abl, endogenous p21 RAS is activated as determined by an elevated ratio of associated guanosine triphosphate (GTP)/guanosine diphosphate (GDP), assayed by thin-layer chromatography of the nucleotides eluted from p21 RAS after immunoprecipitation with the Y13-259 antibody. Treatment of p210 bcr-abl-transformed cells with a specific tyrosine kinase inhibitor herbimycin A resulted in diminished tyrosine phosphorylation of p210 bcr-abl and associated proteins, without major reduction in expression of the p210 bcr-abl protein itself. Inhibition of p210 bcr-abl-dependent tyrosine phosphorylation resulted in a reduction of active p21RAS-GTP complexes in the transformed cells, in diminished expression of the nuclear early response genes c-jun and c-fos, and in lower cellular proliferation rate. To further implicate p21 RAS in these functional events downstream of p210 bcr-abl tyrosine phosphorylation, we targeted G- protein function directly by limiting the availability of GTP with the inosine monophosphate dehydrogenase inhibitor, tiazofurin (TR). In p210 bcr-abl-transformed cells treated for 4 hours with TR, in which the levels of GTP were reduced by 50%, but GDP, guanosine monophosphate, and adenosine triphosphate (ATP) were unaffected, p210 bcr-abl tyrosine phosphorylation was at control levels. However, expression of c-fos and c-jun nuclear proto-oncogenes were strongly inhibited and p21 RAS activity was downregulated. These findings show that p210 bcr-abl transduces proliferative signals, in part, through downstream activation of p21 RAS. Furthermore, p21 RAS activity is linked to pathways that regulate c-jun and c-fos expression. 相似文献
69.
Engraftment of bone marrow cells into normal unprepared hosts: effects of 5-fluorouracil and cell cycle status 总被引:2,自引:7,他引:2
Bone marrow from animals treated with 5-fluorouracil (5FU) competes equally with normal marrow when assessed in vivo in an irradiated mouse, but shows markedly defective engraftment when transplanted into noncytoablated hosts. Using Southern Blot analysis and a Y-chromosome specific probe, we determined the level of engraftment of male donor cells in the bone marrow, spleen, and thymus of unprepared female hosts. We have confirmed the defective engraftment of marrow harvested 6 days after 5FU (FU-6) and transplanted into unprepared hosts and shown that this defect is transient; by 35 days after 5FU (FU-35), engraftment has returned to levels seen with normal marrow. FU-6 marrow represents an actively cycling population of stem cells, and we hypothesize that the cycle status of the stem cell may relate to its capacity to engraft in the nonirradiated host. Accordingly, we have evaluated the cycle status of engrafting normal and FU-6 marrow into normal hosts using an in vivo hydroxyurea technique. We have shown that those cells engrafting from normal marrow and over 70% of the cells engrafting from FU-6 marrow were quiescent, demonstrating no killing with hydroxyurea. We have also used fluorescent in situ hybridization (FISH) analysis with a Y-chromosome probe and demonstrated that normal and post-5FU engraftment patterns in peripheral blood were similar to those seen in bone marrow, spleen, and thymus. Altogether these data indicate that cells engrafting in normal, unprepared hosts are dormant, and the defect that occurs after 5FU is concomitant with the induction of these cells to transit the cell cycle. 相似文献
70.
Human platelets exert cytotoxic effects on tumor cells 总被引:6,自引:0,他引:6
Monocytes are thought to play a role in host resistance to tumor cell growth in animals and humans. In addition, platelets are known to be involved in tumor metastases. To investigate the interaction of these two cell types and their effect on tumor cells, human monocytes and platelets were examined using an in vitro monocyte-tumor cell cytotoxicity assay. Monocytes alone resulted in 32% +/- 1.5 (mean +/- SEM) tumor cell kill. When platelets were added to monocytes in a 1:1 ratio, an increase in cytotoxicity to 61% +/- 3.2 was observed. The cytotoxicity noted when platelets were added to a fixed number of monocytes and tumor cells was dependent on the number of platelets added. A decrease in cytotoxicity from 32% +/- 1.5 to 12% +/- 2.3 was observed when contaminating platelets were removed from monocyte preparations. Platelets added to tumor cells in the absence of any monocytes were also toxic, resulting in a maximum kill of 95% at a 4:1 platelet/tumor cell ratio. Secreted products of freshly isolated platelets may be responsible for much of the observed cytotoxicity, since supernatants from the platelets were toxic for tumor cells. Platelets pretreated with a cyclooxygenase inhibitor (ASA) or a lipoxygenase inhibitor had decreased cytotoxicity compared with untreated platelets. Our results indicate that products of platelet arachidonate metabolism are toxic for tumor cell lines. They also suggest that the role of the platelet must be considered when studying monocyte-tumor cell cytotoxicity. 相似文献