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171.
目的探索不同级别小鼠来源的骨髓细胞对体外制备优势DC2细胞的影响。方法取SPF级和健康普通级C57BL/6小鼠股、胫骨骨髓细胞及脾细胞,设细胞因子诱导的实验组、低浓度GM—CSF对照组、无外源细胞因子对照组及脾细胞组。骨髓细胞采用GM—CSF,IL-4,Fh3L和SCF的不同细胞因子浓度和组合体外培养诱导。脾细胞培养2d去除大部分淋巴细胞,第3天采用流式细胞术4色荧光标记法分析细胞表型,骨髓细胞诱导的各组同样于第3天采用流式细胞术分析细胞表型,比较不同级别小鼠骨髓细胞所诱导的DC2细胞的表型和比例。结果SPF来源的小鼠骨髓细胞诱导的各组第3d在CD11c^+的DC细胞群中CD8α^+DC2所占比例及不成熟DC2的比例均高于普通级小鼠,显示普通鼠来源的骨髓细胞更倾向于产生成熟的DC,不易诱导产生高比例的不成熟的DC2。对两种动物脾细胞DC2的分析结果表明,普通鼠脾脏中CD8α^-~MHCⅡ^+的成熟DC1比例为75.58%,远远超过SPF鼠的30.60%。结论小鼠的微生物级别可影响耐受性DC的诱导效果,采用SPF级小鼠来源的骨髓细胞体外制备优势DC2细胞效果优于普通级鼠,原因可能与普通鼠接触微生物较多,免疫系统更易于产生免疫应答而非免疫耐受有关。  相似文献   
172.
BB creams appeared on the market quite recently. These creams, which give a perfect complexion by covering up the skin’s blemishes, have a photoprotective effect in the majority of cases. An SPF value ranging from 10 to 45 concerning the products we tested is displayed on the packaging. The 21 commercially-available BB creams were tested to assess their efficacy (determination of the SPF) and their photostability (determination of their efficacy after UV irradiation). It was shown that 70% of the products tested have an SPF determined in vitro by us which matches the SPF displayed on the product. For the remaining 30%, it can be seen that products have SPF values of between 2 and 10 times lower than those indicated on the products. It can also be noted that there is a large disparity in terms of photostability since, under the same experimental conditions, however, some products only lose 5% of their photoprotective efficacy, whereas others lose 60%.  相似文献   
173.
Previously, we reported the regional variations in intraepithelial lymphocytes (IELs) in the small intestine of mice. To clarify the effects of intestinal bacteria on the distribution of IELs, regional variations in IELs were examined using germ-free (GF) and specific pathogen-free (SPF) BALB/cA mice. The small intestine was taken and divided equally into three parts (the proximal, middle, and distal parts). IELs were isolated from each part of the intestine, and the total number of IELs in GF mice was about one seventh of that in SPF mice. The decreased number of IELs in GF mice suggests that intestinal bacteria may be essential for local expansion of IELs. On the other hand, similar regional variations in IEL subsets observed in both GF and SPF mice, except for some subsets. The similarity of regional variations in GF and SPF mice indicates that the regional variations in IEL subsets may not fundamentally depend on intestinal bacteria.  相似文献   
174.
Safety evaluation of polyphenols extracted from hop bracts.   总被引:1,自引:0,他引:1  
Hop bract polyphenols contain polyphenols as promising functional ingredients. To assess the safety of topical hop bract polyphenols, Hopsphenon, we examined acute, 14-day, 28-day and 90-day toxicity tests in rats, and mutagenicity tests using Ames test and micronucleus test in mice. The acute, 14-day, 28-day and 90-day toxicity tests revealed that Hopsphenon produced no symptoms of significant injury. The lethal dose of hop bract polyphenols is greater than 2000 mg/kg. The Ames test in the absence of S9 mix for TA98 and in the presence of S9 mix for TA1537 revealed that Hopsphenon had slight mutagenicity at a high dose of 5000 microg/plate; however, in the micronucleus test, Hopsphenon was negative. These tests demonstrated that hop bract polyphenols are safe and do not cause any detrimental effects in vivo under the conditions investigated in this study.  相似文献   
175.
HER2/neu expression in bladder cancer: relationship to cell cycle kinetics   总被引:1,自引:0,他引:1  
BACKGROUND AND OBJECTIVES: The incidence of overexpression of HER2/neu in bladder cancer is one of the highest among all human malignancies tested; such overexpression is thought to play a role in the aberrant proliferation of cancer cells. This study was conducted to evaluate the quantitative assessment of HER2/neu expression by enzyme immunoassay (EIA) and its prognostic significance in differentiating between high and low proliferating tumors. PATIENTS AND METHODS: Tissue samples were collected from 35 patients with benign bladder lesions, 28 with bilharzial bladder cancer, and 25 with nonbilharzial bladder cancer. Twenty normal samples were obtained from normal safety margin areas in nonbilharzial bladder cancer patients. Out of the malignant samples, 22 were found to be squamous cell carcinoma and 31 were transitional cell carcinoma. All samples were examined for HER2/neu expression by EIA and Western blot (WB). Flow cytometric (FCM) analysis was also performed in all the samples provided. RESULTS: HER2/neu was found to be significantly overexpressed in the malignant group compared to the benign and normal groups (P < 0.001) and no significant difference was found between the bilharzial and nonbilharzial cancer groups or between the transitional and squamous cell carcinoma groups. HER2/neu was significantly correlated to ploidy (P = 0.001), synthetic phase fraction, SPF (P = 0.012), and DNA index (P = 0.002). No significant correlation was found between HER2/neu and stage or grade while it was significantly associated with lymph node status of the tumour (P = 0.02). CONCLUSION: HER2/neu can be measured reliably by the EIA method as confirmed by WB. The quantitative assessment of HER2/neu expression in malignant tumors aided by other proliferation markers such as SPF, DI, and ploidy could be useful in selecting patients for more aggressive treatment or for predicting outcome.  相似文献   
176.
OBJECTIVES: Cell proliferation is stimulated by growth factors and inhibited by p15 and p16 gene products. We compared cell regulators, TGF-alpha, p15, and p16, in schistosomal and non-schistosomal bladder cancer to explore possible differences in their alterations between the two subtypes and their correlations with proliferation pattern [synthetic phase fraction (SPF)], DNA ploidy, and clinicopathological factors. METHODS: Tumor tissue samples were obtained from 120 patients. Expressions of p15 and p16 genes were investigated by the polymerase chain reaction, while TGF-alpha protein expression was measured by an enzyme immunoassay (EIA) method. RESULTS: Deletion of both p15 and p16 was observed in 62 and 46 bladder tumors, respectively. TGF-alpha was overexpressed in 64 bladder tumors. A highly significant association was observed between the two deleted genes and TGF-alpha positivity. Of the entire group, p15 and p16 alteration and positive TGF-alpha (> or =cutoff value) were significantly expressed in schistosomal bladder cancer (68.1%, 60.9%, and 65.2%), and squamous cell carcinoma type (SCC) (69.1%, 64.7% and 72.1%) compared to those with non-schistosomal bladder cancer (29.4%, 7.8%, and 37.3%) or transitional cell carcinoma (TCC) (28.8%, 3.8%, and 28.8), respectively. A significant association between p15 and p16 deletion and TGF-alpha positivity with high SPF, aneuploid DNA pattern, late stages, and high histological grades was also documented. CONCLUSION: Alteration of p15 and p16 genes and overexpression of TGF-alpha appears to be an event in bladder cancer that occurs more frequently in schistosomal bladder cancer and SCC, and may play an important role in their development. These observations may provide insight into treatment guided by molecular changes.  相似文献   
177.
[目的]研究采用SPF-290分析仪及一种新型载体聚甲基丙烯酸甲酯板对防晒产品的抗水性能进行评价的可行性。[方法]对15个经人体试验证实具有抗水性能的防晒化妆品用SPF-290分析仪及振荡水槽进行测定。[结果]抗水性的测试结果与相应的人体试验结果相当吻合,符合率为14/15。[结论]用本法取代人体法来测定防晒化妆品的抗水能力是可行的。  相似文献   
178.
SPF小型猪血液学、血液生化正常参考值、尿常规值测定   总被引:1,自引:0,他引:1  
本实验选用20头60dSPF小型猪,雌雄各半,对其26项血液常规、生化正常值和18项尿常规值进行测定,并将雌雄SPF小型猪血液常规、生化常值、尿常规值进行比较.结果表明SPF小型猪血、尿值变动幅度更小,SPF小型猪血液成分变化趋势与文献报道SPF大、小鼠血液成分变化趋势一致,红细胞(RBC)总数、血红蛋白(Hgb)量较高,白细胞(WBC)总数、中性粒细胞(NEUTRO)较低.淋巴细胞(LYM)、中性粒细胞分叶型(NEUTROl)、血清球蛋白(GLOb)、白球比(ABG)相差非常显著(P<0.01);淋巴细胞、白球比雌性高于雄性,中性粒细胞分叶型、血清球蛋白雄性高于雌性;血小板总数(PLT)、酸性粒细胞(EO)、血液pH值(pH)、血清白蛋白(ALB)、血清氯(Cl)、血清钠(Na)、血清钙(Ca)、血清磷(P)相差显著(p<0.05);血液pH值、血清白蛋白、血清钙、血清磷雌性高于雄性;血小板总数、酸性粒细胞、血清氯、血清钠雄性高于雌性;其他血液常规、生化常值及18项尿常规值,雌雄SPF小型猪相差不显著(p>0.05).  相似文献   
179.
Seabuckthorn (Hippophae rhamnoides L.) has been traditionally used as medicine and nutritional supplement for a long period of time. However, information on the systemic toxicity and safety evaluation of seabuckthorn and its extracts is still scarce. The purpose of this study was to evaluate the potential toxicity of seabuckthorn oil by an acute oral toxicity study in mice and a 90-day repeated oral toxicity study in rats. No mortality or signs of toxicity was observed in mice treated with 20 mL/kg body weight seabuckthorn oil in the acute toxicity study. In the subchronic toxicity study, 80 Sprague-Dawley rats (10 animals per sex per treatment group) were administrated with 10, 5, 2.5 and 0 (control) mL/kg body weight of seabuckthorn oil daily for 90 days by gavage. There were no signs of toxicity and treatment-related changes in rats treated with seabuckthorn oil on mortality, body and organ weights, food consumption, blood biochemistry and hematology, gross necropsy and histopathological examinations. Based on the finding of this study, the maximum tolerated dose of seabuckthorn oil was >20 mL/kg for mice for acute toxicity study, and the no-observed-adverse-effect level was 10 mL/kg body weight for both male and female rats for 90-day toxicity study.  相似文献   
180.
Timosaponin BII (TBII), a major steroidal saponin isolated from Anemarrhena asphodeloides Bge., displays a variety of promising pharmacological activities, such as neuroprotection, enhancement of learning and memory, vascular protection and inhibition of platelet aggregation; therefore, it has been developed as a pharmaceutical for prevention or treatment of dementia. Given the safety concerns surrounding timosaponins and the absence of studies on the safety of TBII, the potential toxicity of TBII was evaluated in toxicity and toxicokinetic studies in rats. In the acute oral toxicity study, loose stools were observed in rats receiving 4000 mg/kg, and the symptoms recovered within 1 day. In the 28-day repeated-dose oral toxicity and toxicokinetic study, rats receiving 540 mg/kg showed loose stools and a slight deceleration of body weight growth in both sexes, and the females also showed a slight decrease in food consumption. Moreover, urinalysis indicated reversible treatment-related toxicity in rats receiving 540 mg/kg. The toxicokinetic study demonstrated a dose-dependent increase in systematic exposure to TBII after 28 successive days of oral treatment with TBII. The accumulation coefficients of TBII were 4.35, 1.70 and 1.81, respectively, in rats that received 60, 180 and 540 mg/kg. The no-observed-adverse-effect level (NOAEL) is proposed to be 180 mg/kg.  相似文献   
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