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991.
Two new sesquiterpenoids have been isolated from Cremanthodium ellisii Kitam. Their structures were established on the basis of spectral analysis (IR, MS, 1H-1H COSY, NOESY, 1H-13C COSY, and COLOC) and chemical evidence. 相似文献
992.
人眼小梁细胞体外表达表皮生长因子mRNA和表皮生长因子受体 总被引:6,自引:2,他引:4
目的 了解培养的小梁细胞分泌表皮生长因子(epidermal growth factor,EGF)及细胞膜上表皮生长因子受体(epidermal growth factor receptor,EGFR)的情况。方法 进行人眼小梁细胞体外培养。用EGF cDAN探针,α^-32p同位素标记及斑点杂交放射自显影法,检测小梁细胞分泌EGFmRNA的情况。结果 人眼小梁细胞体外培养成功。免疫组化染色显示小 相似文献
993.
Until now, no large series studies on the clinicopathological features of primary liver tumors (PLTs) in mainland China have been reported. The authors retrospectively investigated 3,160 cases of PLTs surgically resected at Shanghai Oriental Hospital of Hepatobiliary Surgery between January 1982 and January 1996. Most of them are true neoplasms, others are tumor-like lesions. The 3,160 cases of PLTs could be divided into 3 groups of 25 types arising from three germinal layers, of which tumor-like lesions (Group 1) were of 4 types involving 112 cases (3.5%), benign PLTs (Group 2) were of 10 types involving 499 cases (15.8%) and malignant PLTs (Group 3) were of 11 types involving 2,549 cases (80.7%). The most common type of lesion in each group was solitary necrotic nodule, cavernous hemangioma and hepatocellular carcinoma (HCC), accounting for 73.2%, 74.3% and 96.6% of their respective groups. The patients ranged in age from 5 months to 79 years (mean, 45.7 years), but the age distribution and sex ratio varied reciprocally from group to group and from lesion to lesion. For example, the mean age of the patients in Group 1 was 39.1 years of age, whereas in Group 2 and Group 3, it was 45.9 years and 49.6 years, respectively. The sex ratio of men to women was 2.6:1 in Group 1, 1:1.1 in Group 2 and 7.7:1 in Group 3. The rates of serum HBsAg positivity and concomitant liver cirrhosis in the patients with HCC were 74.4% and 72%, respectively, and the concomitant rate of cirrhosis in small HCC (<3 cm in diameter) was as high as 83.3% (P<0.05), demonstrating a close relationship of HCC with HBV infection and liver cirrhosis. HCC amounts to 78.4% of the total 3,160 PLTs in this series, indicating that HCC is the most common malignant tumor of the liver in China. 相似文献
994.
International emergency medical services (EMS) consultation requires many sensitivities to cross-cultural issues. Contemporary EMS models in developed countries have, by necessity, a systems framework. This study compares evolving EMS systems in the United States and China. It is concluded, that, no matter what the potential and cultural differences might be, a systems framework inherently will emerge in EMS development. As such, the EMS components recognized often will expose an evolving systems approach with more similarities than differences and can reveal strategies for improvement. Providing a developmental comparison process is a necessary first phase in analysis of a country's systems development or restructuring. 相似文献
995.
Edna H. G. Venneker Willem J. Remme MD PhD Diederik C. A. van Hoogenhuyze X. Hanno Krauss G. Louis Bartels Dick A. C. M. Kruijssen Cock J. Storm Dick van Schelven 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1994,8(2):211-219
Summary Antiischemic effects of 1-blocking agents are based on intrinsic negative inotropic and chronotropic properties. Partial 1-agonistic activity, although useful in preserving cardiac function, may counteract such antischemic properties by modulating the intrinsic negative cardiac effects of beta-blockade. To investigate the acute hemodynamic and antiischemic profile of epanolol, a cardioselective 1-antagonist and partial agonist, 20 patients with left coronary artery disease underwent two incremental atrial pacing tests, 45 minutes before (APST I) and 15 minutes after (APST II) 4 mg intravenous epanolol, administered over 5 minutes. Additional measurements were carried out at 1, 3, 5, 10, and 15 minutes after epanolol, at basal and fixed heart rates. Epanolol immediately reduced heart rate with a maximum of 10% at 15 minutes and decreased contractility (Vmax) by 7% (both p<.05), whereas cardiac output fell temporarily by 9% (p<.05). Other hemodynamic parameters did not change, except for a significant 11% reduction in myocardial oxygen demand. Despite comparable pacing conditions, both the double product and contractility decreased significantly less during APST II, resulting in a 17% lower myocardial oxygen consumption (p<.05). Myocardial ischemia was markedly reduced, indicated by normalization of lactate metabolism [lactate extraction 16±7% vs. –7±8% (APST I)], less ST depression (21%), and modulation of LV end-diastolic pressure postpacing (all p<.05 vs. APST I), whereas angina was absent or less in 14 patients. None of the patients reported an adverse effect. Thus, under resting conditions intravenous epanolol induces moderate, short-lasting negative chronotropic and inotropic effects, but does not alter cardiac pump function or vascular resistance, reflecting its additional 1-agonistic properties. Alternatively, during pacing it still reduces ischemia through negative inotropic effects and diminishes myocardial oxygen demand, reflecting its 1-antagonistic profile. 相似文献
996.
Tyagi NK Bharambe MS Garg BS Mathur JS Goswami K 《Indian journal of maternal and child health : official publication of Indian Maternal and Child Health Association,》1994,5(4):99-102
During 1981-1991 at a rural teaching hospital (Kasturba Hospital) of Mahatma Gandhi Institute of Medical Sciences in Sevagram, Wardha, India, 454 of 13,939 newborns died during the early neonatal period for an early neonatal mortality rate (ENMR) of 33.7/1000 live births. The ENMR for boys was not significantly different from that for girls (36.1 vs. 28.6). Community medicine specialists analyzed data on these early neonatal deaths to examine distribution of early neonatal mortality, especially its relationship with prematurity, low birth weight, birth order, and by sex. They calculated average percent deaths (APD) per hour to examine the dynamics in early neonatal mortality. The mean age at death was lower among newborns of birth order greater than 2 than those of birth order less than 2 (23.47 vs. 26.85 hours; p 0.001). ENMR was higher for newborns of birth order greater than 2 than those of birth order less than 2 (41.74% vs. 27.35%; P 0.001). The mean age at death increased as gestation increased (10.34 for 28 weeks; 24.27 for 28-33 weeks, 31.53 for 33-37 weeks, and 34.43 for 37 weeks; p 0.001). ENMR decreased as gestation increased (850 for 28 weeks; 375 for 28-33 weeks, 147.02 for 33-37 weeks, and 8.77 for 37 weeks; p 0.001). The mean age at death increased as birth weight increased for newborns weighing less than 1500 gms through 2000-2500 gms (23.36-37.13 hours; p 0.001). It was lowest among those weighing more 3000 gms (11.55 gms). ENMR fell as birth weight increased (614.33 for 1500 gms, 116.19 for 1500-2000 gms, 19.38 for 2000-2500 gms, 10.99 for 2500-3000 gms, and 5.41 for 3000 gms; p 0.001). The APD/hour for the first hour of life was 3.74% for a relative risk of 12.9. It decreased steadily as the hours of life increased (3.08% for 1-6 hours, 1.19% for 6-24 hours, 0.67% for 24-72 hours, and 0.29% for 72-168 hours). Knowledge of time of likely death can help providers know where they need to focus their attention to prevent early neonatal deaths. 相似文献
997.
Several studies have demonstrated a paradoxical form of antinociception induced by the repeated administration of opioid antagonists accompanied by exposure to a painful stimulus. The underlying mechanism of this naloxone-induced antinociception (NIA) is still unknown, but the results of several studies suggest that it is a non-opioid response. This study was designed to investigate serotonergic and noradrenergic involvement in NIA. Rats were treated daily with systemic injections of 5 mg/kg naloxone, followed by a 45-s hot plate test of nociception (temperature=51.5 ± 0.5°C). After rats reached plateau levels of NIA, they received a test trial in which they were treated with various doses of different selective 5-HT or 2 adrenoceptor antagonists in addition to naloxone before the hot plate test. Rats treated with 0.16, 0.32 and 0.63 mg/kg pirenperone or 2.5 mg/kg ritanserin showed significant reductions in paw lick latency with respect to rats treated with vehicle. In addition, high doses of yohimbine (7.5–10 mg/kg) also effectively reversed NIA. In contrast, NIA was not affected by acute blockade of 5-HT1 or 5-HT3 receptors by methiothepin or MDL 72222, respectively, or by the 2 adrenoceptor blocker idazoxan. None of the 5-HT or 2 adrenoceptor antagonists had any effect on the paw lick latencies of saline-treated rats. A possible role of 5-HT2 receptors in the antinociception induced by opioid receptor blockade is discussed. 相似文献
998.
Water-soluble vitamins, amino acids, and nontoxic pharmaceutical excipients were studied as solubilizing agents for poorly water-soluble adenine (nucleic acid base), guanosine (nucleoside), and structurally related drugs (acyclovir and triamterene). The apparent solubility of the substrates (adenine, guanosine, acyclovir, or triamterene) was appreciably increased by forming complexes with the ligands (vitamins, amino acids, or other ligand). Apparent association constants (K
a ) values were measured at 25°C in pH 7 phosphate buffer using phase solubility analysis. The effect of combination ligands on substrate solubility was also studied. Additive solubility enhancement was obtained for several ligand pairs. 相似文献
999.
The effects of acute and chronic stages of carrageenan-induced air-pouch inflammation on the pharmacokinetics of prednisolone were studied in male Wistar rats. Chronic inflammation produced a significant increase in the area under the curve (AUC) of prednisolone compared to control animals (6594 ± 2144 vs 3530 ± 2164 µg · hr/ L). The effect of acute inflammation was not significant (AUC = 4996 ± 3813). Both acute and chronic inflammation also reduced thein vitro plasma protein binding of prednisolone, the reduction being much greater after chronic inflammation. The AUC of free prednisolone after chronic inflammation was 3141 µg · hr/L, compared to 1121 µg · hr/L in the control group and 1823 µg · hr/L after acute inflammation. The mean values of half-life and apparent volume of distribution at steady-state in each group were similar. These results indicate that prednisolone must be used with caution in the treatment of inflammatory diseases because of higher free concentrations of the steroid. 相似文献
1000.
Seventy paired tumor and blood samples from patients with upper aerodigestive tract squamous cell carcinoma (UADT SCC) were tested for allelic loss on chromosome 13. Increased loss of heterozygosity (LOH) was observed at 11 of 13 different highly polymorphic microsatellite 'CA' dinucleotide repeat-containing loci. Increasing percent LOH correlated with lymph node metastasis (N Stage) (p=0.016). LOH was also detected in 10 of 16 (63%) informative samples of histologically normal mucosa adjacent to the tumors. These findings demonstrate that allelic loss on chromosome 13 is a frequent event in UADT SCC. Furthermore, these genetic alterations can be detected prior to histological changes in normal mucosa adjacent to these tumors. 相似文献