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991.
目的观察比较基质金属蛋白酶(MMPs)和基质金属蛋白酶抑制物(TIMPs)在异位、在位和正常子宫内膜中的表达,探讨其与子宫内膜异位症(内异症)的关系.方法应用免疫组化LSAB法和KS 400图像分析系统,检测MMP-9和TIMP-3在26例卵巢子宫内膜异位囊肿患者的异位子宫内膜和其中15例在位子宫内膜中的表达,分析阳性细胞的分布规律,以20例正常子宫内膜作为对照.结果 MMP-9和TIMP-3在正常和异位子宫内膜的腺上皮细胞、基质细胞中均有不同程度的表达.异位子宫内膜组织中MMP-9呈高表达状态, TIMP-3表达减少,与正常子宫内膜和在位内膜相比有显著差异 (P<0.05);在位子宫内膜与正常子宫内膜MMP-9和TIMP-3的表达无显著差异(P>0.05).结论提示异位内膜组织具有更强的侵袭力,其在子宫内膜异位症发病中起重要作用.  相似文献   
992.
目的:研究双益方、组方中药及有效成分对骨骼肌细胞胰岛素抵抗模型葡萄糖消耗量及人肝癌HepG2细胞糖原合成,己糖激酶(hexokinase,HK),丙酮酸激酶(pyruvate kinase,PK)活性的影响,初步探讨其作用机制,为其临床应用奠定基础。方法:采用高胰岛素方法建立骨骼肌细胞的胰岛素抵抗(IR)模型,观察双益方低、中、高剂量组、组方中药(黄芪、山茱萸、黄连、桑白皮、葛根、佩兰),有效成分(黄芪甲苷,毛蕊异黄酮葡萄糖苷,熊果酸,马钱苷,小檗碱,1-脱氧野尻霉素,葛根素)组(30,120,480μg·L-1)对骨骼肌细胞胰岛素抵抗模型的葡萄糖消耗量的影响,蛋白质免疫印迹法(Western blot)测定骨骼肌细胞蛋白酪氨酸磷酸酶-1B(protein tyrosine phosphatase-1B,PTP-1B),葡萄糖转运蛋白4(glucosetransporters 4,GLUT4)表达;建立HepG2细胞的胰岛素抵抗模型,研究双益方、组方中药及其有效成分对HepG2细胞糖原合成及己糖激酶、丙酮酸激酶活性的影响。结果:双益方,黄芪,山茱萸,黄芪甲苷,1-脱氧野尻霉素,葛根素可降低骨骼肌细胞细胞上清液葡萄糖浓度(P0.05),以480μg·L-1双益方,黄芪甲苷组及葛根素组效果较好;与模型组比较,双益方、黄芪及有效成分组方可降低PTP-1B,提高GLUT-4的表达(P0.05,P0.01)。与正常组比较,模型组糖原合成量及HK,PK活性显著降低(P0.01);与模型组比较,各浓度组单味中药及有效成分均能一定程度的增加糖原合成量及HK,PK活性(P0.05,P0.01),其中黄芪甲苷、黄芪提取液增加糖原合成及提高HK活性作用较好;双益方提取液及葛根素增加PK活性作用较好。结论:双益方、组方中药及有效成分对骨骼肌,HepG2细胞胰岛素抵抗具有一定缓解作用,降低PTP-1B表达、提高GLUT4表达、增加糖原合成、提高HK,PK活性可能是其作用机制。  相似文献   
993.
Samples of Jamaican plants used as bush teas were collected from households in high soil-cadmium (Cd) areas of central Jamaica and analysed by graphite furnace atomic absorption spectrophotometry for total cadmium and for cadmium extractable with a hot water brew as prepared for human consumption to determine their contribution to dietary cadmium exposure. The concentrations ranged from < 0.03 to 6.85 μg/g for total Cd, between 1 and 15% of which was extracted with a hot water brew. One cup (200 ml) of the teas examined was found to contain < 0.04–1.18 μg of Cd and would contribute 0.1 – 0.3 μg of Cd to a person''s dietary intake. This is significantly below the provisional tolerable weekly intake (PTWI) of 7 μg Cd/kg body weight established by the World Health Organization (WHO). While this suggests that bush tea consumption does not contribute significantly to the PTWI, some of the teas examined exceed the WHO recommendation of less than 0.3 mg/kg Cd for medicinal plants.  相似文献   
994.
995.
996.
Miller  ME; Boxer  LA; Kawaoka  EJ; Border  WA 《Blood》1981,57(1):22-24
Cell elastimetry has been applied to the measurement of antineutrophil antibodies. This technique measures, under direct visualization, the negative pressure required of aspirate PMNs into small-pored pipettes. Two groups of studies were carried out: (A) In the first group of studies, normal PMNs were incubated with 1 of 8 known antineutrophil serums. Each serum significantly decreased membrane deformability-- i.e., cells became more rigid. The study was conducted in an entirely blind fashion. Randomly coded serums from patients and controls were studied for deformability by observers unaware of the code. (B) In the second group of studies, sera containing immune complexes were incubated with normal PMNs. No significant effects were noted upon deformability. As a single cell assay that partially reflects membrane rigidity, elastimetry may, therefore, have potential in the further characterization of mechanisms by which such antineutrophil antibodies compromise neutrophil functions.  相似文献   
997.
目的:观察百令胶囊佐治小儿反复呼吸道感染的疗效。方法:采用百令胶囊佐治小儿反复呼吸道感染27例,并设对照组观察。结果:治疗组总有效率为96.2%,对照组总有效率为75.0%;治疗组疗效优于对照组(P0.05)。结论:百令胶囊可通过增强机体免疫力和抗病能力来提高治疗小儿反复呼吸道感染临床疗效。  相似文献   
998.
Objective To investigate the iodine nourishment in women of child-beating age in high risk region of iodine deficiency disorders (IDD) in Qinghai Province. Methods According to The Notice to Launch a Reinforced Survey on IDD in High Risk Region issued by The Ministry of Public Health, 17 counties in 6 districts were selected as investigated area in Qinghai Province in 2007, using two stage cluster sampling and combining The National IDD Preliminary Surveillance Scheme, 30 women aged from 18 to 40 years were selected in each village, 1 or 2 villages in each town, 3 to 5 towns in each county, who were divided into newly wedding, pregnant, lactation and other women of child-bearing age. Iodine concentration in urine was detected by the method of As3+-Ce4+catalytic spectrophotometry. Results One thousand six hundreds and four urine iodine samples were analyzed. The median was 93.3 μg/L,52.1%(836/1604),31.8%(510/1604) and 12.4%(199/1604) was lower than 100,50 and 20 μg/L, respectively. It was 70.5%(527/747) and 43.0%(128/298) of women in Yushu and Haixi that had urinary iodine lower than 100 μg/L, respectively, while it was 50% of women in the 6 districts, to be specific, 88.3%(91/103) in Nangqian, 83.8% (62/74) in Zaduo and 70.7%(118/167) in Zhiduo Counties respectively. The median of urinary iodine in women who were not lactating and not pregnant was only 88.6 μg/L, of whom 53.9% (763/1415) lower than 100 μg/L. Conclusions The women of reproductive age in high risk region of IDD are deficient of iodine in Qinghai Province.  相似文献   
999.
The mechanism(s) responsible for the release of brain natriuretic peptide (BNP), a cardiac hormone of ventricular origin, are still not completely understood. We measured plasma atrial natriuretic peptide (ANP) and BNP in 15 subjects (10 men, mean age 67 ± 3 years) with a dual chamber pacemaker and unimpaired heart function during ventricular pacing, which is known to induce an increase in atrial pressure and plasma ANP concentration. Under ECC monitoring, all subjects received sequential atrioventricular pacing for 30 minutes and ventricular pacing for 30 minutes, at the same rate of 80 beats/min. Arterial pressure and plasma BNP and ANP levels were measured every 10 minutes throughout the study. Ventricular pacing led to atrioventricular dissociation in eight subjects and to retrograde ventriculo-atrial conduction in seven. Arterial pressure remained unchanged in all subjects. In the group with atrioventricular dissociation, plasma ANP increased from 10.14 ± 0.58 to 16.72 ± 0.92 fmol/mL at the 60th minute (P < 0.0001), whereas plasma BNP did not change at all (fiom 1.26 ± 0.07 to 1.16 ± 0.09 fmol/mL). In the group with retrograde conduction, plasma ANP concentration doubled (fiom 10.95 ± 1.66 to 21.40 ± 1.51 fmol/mL, P < 0.0001), BNP increased 1.5-fold (from 1.16 ± 0.06 to 1.64 ± 0.14 fmol/mL, P < 0.001), and the ANP: BNP ratio augmented fiom 10:1 to 13.4:1. These results indicate that the release of ANP and BNP is regulated by different mechanisms, supporting the view that there is a dual natriuretic peptide system, comprising ANP fiom the atria and BNP fiom the ventricles.  相似文献   
1000.
Cardiac resynchronization therapy (CRT) improves myocardial performance in patients with heart failure (HF) and left bundle-branch block (LBBB). Tissue Doppler echocardiography (TDE) has already been used to guide the selection of candidates for CRT. The objective of this study is to correlate the effects of CRT on left ventricular (LV) systolic function with wall motion synchrony assessed by TDE. High frame TDE data were obtained in 15 patients (mean age = 68.9 years, 11 men) with LBBB (QRS = 163 ± 13 ms) to derive temporal intraventricular horizontal asynchrony indexes, expressed as the time difference at the onset of shortening between the septum and the lateral (S-L) and antero-inferior (A-I) walls, and measure the amount of delayed longitudinal contraction (DLC) within the LV. All measurements were made at baseline, 24 hours after implantation, and at 1 year of follow-up. The results show that LV ejection fraction (EF) increased from 25 ± 6.2% at baseline to 36.9 ± 7.9% at 1 year, and was strongly related to DLC, expressed either by time duration (DLCd, r =−0.51; P < 0.0001) or percent of the basal segments (%DLC, r =−0.50; P < 0.001). New York Heart Association functional class, which decreased from 3.6 ± 0.5 to 2.3 ± 0.8, was correlated with %DLC (r = 0.50) and DLCd (r = 0.48, P < 0.001). Weaker correlations were found between LVEF and S-Li (r =−0.40) and between NYHA and S-Li (r = 0.40). It is concluded that DLC was the best among intraventricular asynchrony indexes in predicting increases in LVEF after CRT. DLC may be useful to identify responders to CRT.  相似文献   
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