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1.
We monitored the circadian profiles of cortisol, systolic and diastolic blood pressure (SBP and DBP) and heart rate (HR) in 33 matched normotensive subjects, 32 patients with essential hypertension and 16 patients with Cushing's Syndrome (8 pituitary adenomas, 6 adrenal adenomas and 2 adrenal carcinomas). Each subject underwent serial blood drawings at 4-hr intervals along the 24-hr cycle. BP and HR were automatically recorded every 30 min. Data were analyzed by conventional statistics and by chronobiological procedures (cosinor rhythmometry). Both the control subjects and essential hypertensives showed a circadian profile of BP and HR characterized by a peak in the early afternoon and a clear nocturnal fall (rhythm detection: P less than 0.001). The rhythmicity of BP was disrupted in patients affected by Cushing's Syndrome, whereas the 24-hr oscillation of HR was preserved (P less than 0.001). Our data are compatible with the view that glucocorticoids are involved in the control of BP circadian rhythm, whereas HR is not under their control.  相似文献   
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A number of studies performed in vitro and on experimental animals supported the view that pineal gland inhibits neoplastic growth. Data in humans are scanty and controversial. In the present study we measured serum melatonin (MT), prolactin (PRL) and growth hormone (GH) concentrations, at 08.00 and 24.00, in 132 cancer patients and in 58 healthy control subjects. The patients were stratified according to histology and stage of disease as follows: 30 stage I–II and 45 stage III–IV breast cancer (BC); 39 stage III–IV lung cancer; 18 advanced gastrointestinal (GI) cancer. We also measured MT levels, at the same time-points, in 20 women with primary BC before and after radical mastectomy. Finally, we evaluated the circadian rhythm of serum MT in 18 patients with advanced cancer. On the whole, the patients with advanced tumors showed serum MT levels significantly higher than controls, without any correlation with PRL and GH values. When looking at stage III–IV vs stage I–II BC patients, significantly higher MT levels have been found in the former group. The surgical removal of the primary BC was not associated with any changes in MT values at both time points considered. A highly significant rhythm of serum MT was recorded in advanced cancer patients and the rhythmic parameters were substantially superimposable on those of the control subjects.  相似文献   
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Nineteen host plant volatiles (HPVs) were screened for attractivity to adult codling moth Cydia pomonella (L.) as a fourth component of core blends (3K) including (E,Z)-2,4-ethyl decadienoate, (E)-4,8-dimethyl-1,3,7-nonatriene and acetic acid. Each new quaternary combination was compared with a previously reported attractive bisexual lure (4K), consisting of the 3K blend plus 6-ethenyl-2,2,6-trimethyloxan-3-ol (pyranoid linalool oxide, pyrLOX). All lure evaluations were conducted in apple, Malus domestica (Borkhausen). Several compounds were found to significantly lower total and/or female catches when added to the 3K blend, including (Z)-3-hexenol, (E)-2-hexanal and hexyl butanoate (female and total moths), and (Z)-3-hexenyl acetate and linalool (female moths). Other compounds when added to the 3K blend did not increase or decrease moth catches, including methyl salicylate, (E)-β-ocimene, limonene, β-caryophyllene, butyl hexanoate, farnesol, terpineol, terpinen-4-ol and α-pinene. A few added compounds significantly increased moth catches compared with the 3K blend, including β-pinene (male moths), (Z)-jasmone (male and total moths), (E)-β-farnesene and β-myrcene (female and total moths), and (E,E)-α-farnesene (male, female, and total moths). In addition, each of these five compounds when added to the 3K core blend performed similarly to the 4K lure (male, females, and total moths). Further studies should expand these results through tests of these and other new blends with a range of component ratios and total loading amounts. Field trials should also be replicated within all host crops of codling moth and across major geographical production regions.  相似文献   
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Planta - Cold-acclimation genes in woody dicots without winter-dormancy, e.g., olive-tree, need investigation. Positive relationships between OeFAD8, OeOSM , and OeLIP19 and olive-tree...  相似文献   
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Anion channels and transporters in plant cell membranes   总被引:2,自引:0,他引:2  
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Among the factors produced at inflammatory sites and those capable of modulating dendritic cell (DC) functions, PGD(2) may be important in the outcome of immune responses. The biological roles for PGD(2) are in part effected through two plasma membrane G protein-coupled receptors: the D prostanoid (DP) receptor and the chemoattractant receptor-homologous molecule expressed on Th2 lymphocytes (CRTH2). In this report, we studied the effects of PGD(2) and of its major physiological metabolite, 15-deoxy-Delta(12,14)-PGJ(2) (15d-PGJ(2)), on the functions of human monocyte-derived DC. First, we show that PGD(2) exerts in vitro chemotactic effects on monocytes via CRTH2 activation while it inhibits the chemokine-driven migration of monocyte-derived DC through DP. We also report that PGD(2) and 15d-PGJ(2) alter the LPS- and allergen-induced DC maturation and enhance the CD80/CD86 ratio on mature DC in a DP- and CRTH2-independent manner. Moreover, PGD(2) and 15d-PGJ(2) strongly reduce the secretion of the Th1 promoting cytokine IL-12 and affect the synthesis of chemokines involved in Th1 cell chemotaxis, particularly CXCL10. Inhibition of cytokine/chemokine secretion implicates at least in part DP, but not CRTH2. The effects exerted by PGD(2) are associated with the phosphorylation of CREB, but do not parallel with the deactivation of the NF-kappa B and mitogen-activated protein kinase pathways. In contrast, 15d-PGJ(2) seems to target other cellular proteins. Finally, in a model of Th CD45RA(+) differentiation induced by allergen- and superantigen-pulsed DC, PGD(2) impacts on the orientation of the immune response by favoring a Th2 response.  相似文献   
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