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1.
Amphidinium klebsii cultures grown under different light intensities exhibited similar chlorophyll a content per cell. Among the accessory pigments, chlorophyll c concentration decreased slightly in cells exposed to increasing light intensities up to 0.129 ly/min. The concentration of the 2 major xanthophylls present in A. klebsii cells–peridinin and diadinoxanthin–however, varied according to the light background of the cells. Some biochemical pathways in the formation of peridinin in dinoflagellates are discussed.  相似文献   
2.
Molecular Biology Reports - Serotoninergic system is one of the most important neurotransmission systems investigated in the field of psychiatry. Extensive evidence reveals how alterations of this...  相似文献   
3.
4.
Starting from a orexin 1 receptor selective antagonist 4,4-disubstituted piperidine series a novel potent 5-azaspiro[2.4]heptane dual orexin 1 and orexin 2 receptor antagonist class has been discovered. SAR and Pharmacokinetic optimization of this series is herein disclosed. Lead compound 15 exhibits potent activity against orexin 1 and orexin 2 receptors along with low cytochrome P450 inhibition potential, good brain penetration and oral bioavailability in rats.  相似文献   
5.

Background

Kidney function declines considerably with age, but little is known about its clinical significance in the oldest-old.

Objectives

To study the association between reduced glomerular filtration rate (GFR) estimated according to five equations with mortality in the oldest-old.

Design

Prospective population-based study.

Setting

Municipality of Biella, Piedmont, Italy.

Participants

700 subjects aged 85 and older participating in the “Health and Anemia” Study in 2007–2008.

Measurements

GFR was estimated using five creatinine-based equations: the Cockcroft-Gault (C-G), Modification of Diet in Renal Disease (MDRD), MAYO Clinic, Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Berlin Initiative Study-1 (BIS-1). Survival analysis was used to study mortality in subjects with reduced eGFR (<60 mL/min/1.73m2) compared to subjects with eGFR ≥60 mL/min/1.73m2.

Results

Prevalence of reduced GFR was 90.7% with the C-G, 48.1% with MDRD, 23.3% with MAYO, 53.6% with CKD-EPI and 84.4% with BIS-1. After adjustment for confounders, two-year mortality was significantly increased in subjects with reduced eGFR using BIS-1 and C-G equations (adjusted HRs: 2.88 and 3.30, respectively). Five-year mortality was significantly increased in subjects with eGFR <60 mL/min/1.73m2 using MAYO, CKD-EPI and, in a graduated fashion in reduced eGFR categories, MDRD. After 5 years, oldest old with an eGFR <30 mL/min/1.73m2 showed a significantly higher risk of death whichever equation was used (adjusted HRs between 2.04 and 2.70).

Conclusion

In the oldest old, prevalence of reduced eGFR varies noticeably depending on the equation used. In this population, risk of mortality was significantly higher for reduced GFR estimated with the BIS-1 and C-G equations over the short term. Though after five years the MDRD appeared on the whole a more consistent predictor, differences in mortality prediction among equations over the long term were less apparent. Noteworthy, subjects with a severely reduced GFR were consistently at higher risk of death regardless of the equation used to estimate GFR.  相似文献   
6.
It has been suggested that both the menstrual cycle phase and postoperative changes in prolactin (PRL) secretion at the time of surgery may influence the prognosis of breast cancer. The present study was carried out to evaluate the relation between menstrual cycle period and surgery-induced PRL variations. We evaluated 32 premenopausal women with operable breast carcinoma; 17 were in perimenstrual phase (days 1-6 and 21-28) and 15 were in the mid-cycle (days 7-20) period at the time of surgery. To investigate serum levels of PRL, venous blood samples were collected before and 7 days after surgery. Postoperative hyperprolactinemia occurred in 17/32 patients and it was statistically more frequent in patients surgically treated during the perimenstrual phase than in the mid-cycle phase (12/17 vs 5/15; p less than 0.05), while no other parameter (including axillary node and estrogen receptor status) showed a significant influence on hyperprolactinemia rate. The results suggest that in premenopausal breast cancer patients surgery-induced hyperprolactinemia may be influenced by the menstrual cycle phase at the time of surgery.  相似文献   
7.
Extremophiles - Thermus filiformis is an aerobic thermophilic bacterium isolated from a hot spring in New Zealand. The experimental study of the mechanisms of thermal adaptation is important to...  相似文献   
8.
Spirals of human saphenous veins (HSV), mounted in a 5 ml organ bath containing Krebs-Henseleit solution (37 degrees C), when kept in contact with defibrotide (100-200 ug/ml) for 15 min, enhance (2 and 3 fold) their own basal release of 6-keto-PGF 1 alpha (61 +/- 1.3 pg/mg w.t. n = 12). The phenomenon was long lasting upon repeated washing and sensitive to indomethacin (1 ug/ml). Endothelin-1 (ET-1, 20-40 ng) induced a sustained contraction of HSV and concomitantly released from the venous tissue a proportional amount of 6-keto-PGF 1 alpha. Indomethacin (1 ug/ml), by inhibiting cyclo-oxygenase enzyme, potentiated the contractile activity of ET-1 in HSV whereas exogenous PGE2 (20 ng/ml) considerably reduced the tension developed by the peptide on this venous tissue. Defibrotide (200 ug/ml), by releasing 6-keto-PGF 1 alpha, and other vasoactive prostaglandins, antagonized the contractile effect ET-1 (20 ng) in HSV. This data indicates that the eicosanoid metabolism is involved in the modulation of the potent vasoconstrictor effect of ET-1 in HSV and that PGI2-releaser, such as defibrotide, may have therapeutical value against immoderate changes of venous tone.  相似文献   
9.
Histamine 2.5, 5, 10 or 20 μg/kg i.v. induce a pronounced bronchospasm in guinea-pigs, accompanied by a dose-related increase of TXA2 in arterial blood, as revealed by contraction of rabbit isolated aorta and by radioimmunoassay. Aspirin 10 mg/kg prevented formation of TXA2 like material without significantly modifying the severity of the bronchospasm. Bradykinin 0.5, 1 or 2 μg/kg i.v. acted similarly, except that pretreatment with aspirin blocked both the increased airway resistance and release of TXA2. Aspirin also blocked the increase in blood pressure and heart rate caused by histamine or bradykinin.  相似文献   
10.
Spirals of human saphenous veins (HSV), mounted in a 5 ml organ bath containing Krebs-Henseleit solution (37°C), when kept in contact with defibrotide (100–200 ug/ml) for 15 min, enhance (2 and 3 fold) their own basal release of 6-keto-PGF (61 ± 1.3 pg/mg w.t. n = 12). The phenomenon was long lasting upon repeated washing and sensitive to indomethacin (1 ug/ml). Endothelin-1 (ET-1, 20–40 ng) induced a sustained contraction of HSV and concomitantly released from the venous tissue a proportional amount of 6-keto-PGF.Indomethacin (1 ug/ml), by inhibiting cyclo-oxygenase enzyme, potentiated the contractile activity of ET-1 in HSV whereas exogenous PGE2 (20 ng/ml) considerably reduced the tension developed by the peptide on this venous tissue.Defibrotide (200 ug/ml), by releasing 6-keto-PGF, and other vasoactive prostaglandins, antagonized the contractile effect ET-1 (20 ng) in HSV. This data indicates that the eicosanoid metabolism is involved in the modulation of the potent vasoconstrictor effect of ET-1 in HSV and that PGI2-releaser, such as defibrptide, may have therapeutical value against immoderate changes of venous tone.  相似文献   
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