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21.
为建立一种检测活细胞数的方法,作者采用三磷酸腺苷(ATP)生物荧光液闪测定法检测小鼠纤维瘤细胞株L929.ATP标准曲线工作范围为10 -9~10-5mol/ml,相关系数r=0.9963(P<0.001);当活细胞数在3×1 02~106个/ml时与发光计数值有良好的线性关系,r=0.9922(P<0.001),变异系数 CV = 1%~3%.用ATP生物荧光液闪测定法检测活细胞数灵敏、简便、准确、重复性好,用液闪计数仪即可完成测定,有较大的实用价值.  相似文献   
22.
S Liu  Z Peng  H Wang  J Lou  B He  Q Tang  D Qiu 《华西医科大学学报》2000,31(2):260-1, 268
The method for detecting the number of living cells was studied. Using an adenosine triphosphate (ATP) bioluminescence assay, the present authors reported a perfect linear relationship between lg ATP concentrations and lg luminescence counts (r = 0.9963) as well as a relationship between lg number of cells and lg ATP luminescence counts (r = 0.9922). The detectable cells ranged from 10(2) to 10(6) cells/ml, the coefficients of variation 1-3%. This method is simple, accurate and sensitive and has a high reproducibility.  相似文献   
23.
Heat-shock protein protection   总被引:26,自引:0,他引:26  
  相似文献   
24.
Benign focal epilepsy of childhood (BFEC) is the most common form of epilepsy, in children from 3 to 12 years. Its prognosis is always favourable as far as the epilepsy is concerned. Nevertheless, recent clinical data suggest that children affected by BFEC are more likely to show learning difficulties and behavioural disturbances than their peers. We report here the preliminary findings of a prospective study of 22 children affected with BFEC. Electroclinical and neuropsychological changes observed during the first 18 months of the follow-up strengthen the conclusion of recent neuropsychological studies stressing the correlation between epilepsy and cognitive performances. The cognitive deficits affecting mainly non-verbal functions were significantly correlated with the frequency of seizures and spike-wave discharges and to the lateralization of the epileptic focus in the right hemisphere, whereas frontal functions like attention control, response organization and fine motor speed, were impaired in the presence of active BFEC independently of the lateralization of the epileptic focus. Our results indicate that maturing cognitive functions subserved by a cortical area distant from the epileptic focus are susceptible to interference with epilepsy. Copyright Copyright 1999 S. Karger AG, Basel  相似文献   
25.
The aim of this work was to explain the reasons of two unsuccessful blocks of sciatic nerve even if anaesthetic solution was injected through insulated needle on elicited twitch. The clinical cases were two outpatients undergoing diagnostic arthroscopy of knee under anaesthetic block of sciatic and femoral nerves. In both patients, the muscular twitch appeared when the ischiatic bone was kept in unexpected touch with needle tip. In spite of the attempt to locate correctly the needle (the touch with bone means that the nerve is not in front of the needle tip), the injection of anaesthetic solution was unsuccessful. In clinical environment, when electroinsulated needles gathered total amount of administered current on the needle tip, it was not possible to elicit a twitch just at the moment of touch of the needle with the bone. Referred events disagree with some experimental works performed out of clinical environment, which found that total amount of administered current through an insulated needle gathers always in front of the tip. Our clinical observations seems to confirm an electrolocation mistake called "electrical shadow". The ability of sheathed needles to work as occasional capacitor due to the alternation of two conductor layers (needle shaft and tissue) and of a dielectric (coating material) can explain some missing electrolocations, as the appearance of electric fields within dielectric needle sheathing.  相似文献   
26.
多普勒超声心动图评估左心室舒张末压的研究   总被引:1,自引:0,他引:1  
目的探讨多普勒超声心动图评估左室舒张末压的有效方法与指标。方法对68例病人采用左心导管测压及经胸多普勒超声心动图检测。结果对比研究显示,联合肺静脉与二尖瓣血流频谱分析优于二尖瓣血流频谱分析,肺静脉A峰和二尖瓣A峰时限差值(PAd-Ad)与左室舒张末压实测值呈最佳相关性(r=0.72,P<0.01)。结论认为应用多普勒超声心动图测定PAd与Ad,并以其差值估测左室舒张末压,是一项简便、可靠的无创性评估左室舒张末压的方法。PAd-Ad≥0可作为临床判断左室舒张末压增高[≥2.0kPa(15mmHg)]的一项半定量指标。  相似文献   
27.
We designed an open, non-randomized clinical study to assess as the first endpoint the feasibility of sparing surgery and of preserving organ/function by using neo-adjuvant chemotherapy (NAG) in oral cavity and oropharynx cancer patients, and, as the second endpoint, the clinical response to this treatment approach and its duration. Moreover, an attempt was made to scale the extent of surgery by means of an Arbitrary Scale assigning different percentages to the different extents of surgical resection. Twenty-five patients with primary oral cavity and oropharynx cancer (stage III-TV) were enrolled in the study and were assigned to either the classical Al-Sarrafs regimen (1) (n=15) or to a regimen (2) consisting of cisplatin 80 mg/m(2) i.v. on day 1, 5-FU 600 mg/m(2) on days 2-5 and vinorelbine 20 mg/m(2) on days 2 and 8 (n=10). The 25 patients were all evaluable for response to NAC and 20 of them were evaluable for organ preservation. The overall response (OR) rate was 86.6% (13/15 patients) for regimen 1 (cisplatin + 5-FU) and 80% (8/10 patients) for regimen 2 (cisplatin + 5-FU + vinorelbine). The median follow-up duration was 20.6 months. 5/20 (25%) patients completely avoided surgery, 5/20 (25%) patients had a reduced extent of surgical resection, while: 10/20 (50%) patients received the previously planned surgical resection. Altogether, 10/20 (50%) patients treated with NAC either avoided or achieved a reduction in the previously planned surgical resection. Moreover, organ function was evaluated to support the assessment of treatment outcome in our patients. For this purpose we selected the Performance Status Scale for Head and Neck Cancer Patients: as expected, no significant impairment was detected in the area of comprehensibility of speech, but we were rather surprised that no significant impairment was found in the two areas of eating in public and normalcy of diet. NAG-associated toxicity was moderate and similar in the two chemotherapy regimens. The most relevant contributions offered by our study are represented by i) a Scale aimed at measuring as precisely as possible the reduction of surgical resection made possible by NAC compared to surgery planned before NAC and ii) an attempt to support the results with an assessment of treatment outcome.  相似文献   
28.
楼明 《肉品卫生》2005,(10):26-29
本文作者根据我国鲜蛋生产的实际,提出鲜蛋品质安全控制措施防止食源性疾病发生,以确保鲜蛋的食品卫生与安全。  相似文献   
29.
VEGF、MMP-2、MMP-9在卵巢原发性与转移性癌中表达的研究   总被引:1,自引:0,他引:1  
目的 :探讨VEGF、MMP 2、MMP 9在卵巢原发上皮癌、库肯勃氏瘤中的表达差异及临床病理意义。方法 :采用免疫组化S P染色技术对 83例卵巢癌 (卵巢原发癌 4 5例、库肯勃氏瘤 38例 )进行分析 ,观察VEGF、MMP 2、MMP 9在卵巢癌中的表达。结果 :VEGF在卵巢原发癌和库肯勃氏瘤组织中的表达显著高于正常卵巢组织 (P <0 .0 5 ) ;MMP 2、MMP 9在正常卵巢组织中表达缺如 ;VEGF、MMP 2、MMP 9在卵巢原发癌与库肯勃氏瘤中表达均有显著差异 (P <0 .0 5 ) ;VEGF、MMP 2、MMP 9在库肯勃氏瘤中及卵巢原发癌中 ,任意两指标阳性表达均有正相关性 (P <0 .0 5 )。结论 :VEGF、MMP 2、MMP 9在库肯勃氏瘤的形成机制中起重要作用 ,与肿瘤的浸润转移密切相关 ,并可为鉴别卵巢原发癌与库肯勃氏瘤提供一定的依据  相似文献   
30.
Ramucirumab plus paclitaxel is considered the standard of care in the second-line treatment of gastric carcinoma (GC). The aim of this study was to evaluate plasma vascular endothelial growth factor-A (VEGF-A), VEGF-D, and circulating soluble VEGF receptor-2 (sVEGFR-2) as possible markers of resistance or response to ramucirumab administered with paclitaxel in pretreated metastatic GC patients. Plasma samples were collected at different time points (on days 1 and 15 of the first 3 cycles, at best radiologic response and at disease progression). VEGF-A, VEGF-D and sVEGFR-2 were analysed by ELISA. Correlations of biomarker baseline levels or dynamic changes with outcome measures were assessed. Progression-free survival (PFS) was the primary endpoint of the study. Forty-one patients were enrolled. VEGF-A and VEGF-D, but not sVEGFR-2, values significantly increased during treatment compared to baseline (P < 0.001). A positive correlation between VEGF-A and sVEGFR-2 at cycle 2 was found (P=0.045). At univariate analysis, higher baseline levels of VEGF-A were associated with worse OS (P=0.015). Early increase of sVEGFR-2 levels after the first treatment cycle was the only factor associated with longer PFS (6.6 vs. 3.6 months, P=0.049) and OS (18.6 vs. 5.2 months, P=0.008). Significance of sVEGFR-2 early increase was retained at multivariate analysis for OS (HR 0.32; 95% CI 0.12-0.91; P=0.032). The reported results confirmed the prognostic role of baseline VEGF-A and, with the limitations of the limited sample size and the lack of a control arm, suggested that the early increase of sVEGFR-2 after 1 cycle of treatment could be a potential predictive biomarker of benefit from second-line ramucirumab plus paclitaxel in GC.  相似文献   
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