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1.
Isoflavones (ISOs) are bioactive food ingredients of the traditional East Asian diet and currently discussed as alternatives to classical hormone replacement therapies and for reducing the prevalence of hormone-dependent cancers. Although there are many studies on ISOs, not much is known about their long-term effects.Therefore, we performed an animal experiment analyzing the effects of three different diets: a phytoestrogen-free diet, a diet supplemented with genistein (700 μg/g diet) and an ISO-high diet (232 μg daidzein and 240 μg genistein/g) at two distinct time points, juvenile (21 days) and adult (97 days). Exposure started prior to mating of the parents and throughout the life of the offspring.We observed a stronger increase of uterine wet weights in juvenile offspring with genistein exposure (1018 ± 350 mg/kg BW) than with ISO-high diet (497 ± 133 mg/kg BW). Whereas the expression of proliferation related genes (PCNA; Ki67; IGF-1; IGF-1R), analyzed by real-time-qPCR and Western blot, were significantly down-regulated in juvenile animals exposed to genistein. Additionally, genistein exposure led to estrogenic responses, observed upon increase of complement C3 and decrease of estrogen receptors gene expressions, while the exposure to ISO-high diet did not show these effects.In conclusion, both the time point on which phytoestrogen exposure starts together with the composition of the ingested phytoestrogen containing diet are of great importance for the biological response of the offspring.  相似文献   
2.
In the present study we report on the effects of commonly used nonsteroidal antiinflammatory drugs on metallothionein (MT) and MT-I mRNA levels. A single dose of chloroquine (100 mg/kg), diclofenac (100 mg/kg), indomethacin (10 mg/kg), or piroxicam (100 mg/kg) was administered ip to C57B1 mice. After 18 h, MT levels were determined with a Cd-saturation radioassay. MT-I mRNA levels were measured by Northern Blot analyses using a probe containing the mouse MT-I gene. All drugs tested caused an increase in the MT content of the liver but not of the kidneys and lung. The lowest and highest effects were observed with chloroquine (8 times the control value) and diclofenac (18 times), respectively. In accordance with the stimulation of MT synthesis, increased accumulation of hepatic MT-I mRNA could be demonstrated. These results indicate that elevated MT levels may contribute to the effectiveness of nonsteroidal antiinflammatory drugs in the treatment of rheumatoid arthritis (RA).  相似文献   
3.
Summary Immunohistochemical properties of the terminal nerve network in the rat heart were assessed by use of the elution-restaining method. The colocalization of the enzymes involved in catecholamine synthesis (tyrosine hydroxylase — TH, dopamine--hydroxylase — DBH) as well as the respective distributions of the neuropeptides associated with the adrenergic nervous system (neuropeptide tyrosine — NPY, C-terminal flanking peptide of neuropeptide Y — C-PON) were studied in series of serial sections throughout the interatrial septum and the atrioventricular junction. Our data suggest that ganglion cells of sulcus terminalis as well as the epicardial ganglia enclosed between the superior vena cava and ascending aorta are VIP- and TH-negative, but neuropeptide Y- and DBH-immunoreactive. They give rise to three intraseptal nerves directed towards the specialised structures of the atrioventricular junction. These nerve fascicles contain abundant, thick TH-immunoreactive nerve fibres and scarce, thin NPY- and DBH-immunoreactive fibres. The cell bodies of the intramural ganglion cells localized between the right and left branches of the bundle of His (Moravec and Moravec 1984) are strongly TH- and DBH-immunoreactive. They are innervated by thick nerve fibres having the same immunohistochemical properties (NPY- and DBH-immunoreactivities) as those of a subpopulation of the epicardial ganglion cells and seem to supply some of the TH-immunoreactive nerve fibres directed via the intraseptal nerves to the epicardial ganglia. The existence of a multicomponent nerve network, characterized by a reciprocal innervation of the sinus node and atrioventricular node areas, is suggested by our immunohistochemical data.  相似文献   
4.
Summary We describe a previously unreported glucose-6-phosphate dehydrogenase (G6PD) variant. G6PD Huntsville was found in a Caucasian male, resident of Huntsville, Alabama who was investigated for otherwise unexplained chronic hemolytic anemia. An unusual feature of this unique, apparently hemolytic, G6PD mutant is that its red cell enzymatic activity has not been decreased. The mutant enzyme is unstable. Additionally, the enzyme variant is characterized by normal electrophoretic mobility, biphasic and slightly alkaline pH optimum, and abnormal kinetics for the natural substrates G6PD and NADP as well as the artificial substrates deamino NADP. Its activity for another artificial substrate 2-deoxy G6PD is normal. The inhibition constant for NADPH is normal. The subject has had no evidence of episodic jaundice.  相似文献   
5.
Cluster analyses by different methods and a minimum spanning tree were used to study phenetic relationships in the genusChlerodendrum. 129 species were scored for 52 morphological characters corresponding to 119 character states. The phenetic results suggest a classification into 7 distinct groups, which may be grouped into two subgenera. This classification is supported by the iridoid distribution as well as by some phylogenetic considerations.  相似文献   
6.
The bookK. Richter, Plantae europeae, Vol. 1, 1890, is analyzed from the viewpoint of nomenclature of subspecies names. 264 subspecies names interesting from the standpoint of contemporary taxonomy and nomenclature are selected from the total number of 840 subspecies names for a commented list. Seventeen important cases are dealt with separately in greater detail. Eleven new nomenclatural combinations (two for species, nine for subspecies) are proposed in the Appendix. Types for two generic names (Acorellus Palla andJuncellus C. B. Clarke) are proposed. A new term “parabasionym” is applied for names establishing the priority of infraspecific epithets in the rank in question. The need to respect the newly accepted principle of priority of autonymic subspecies names at proposing new nomenclatural combinations is stressed. Examples ofRichter’s subspecies names having priority, subspecies names with necessary changes in their authorship and names having a possible importance as parabasionyms are enumerated in separate lists.  相似文献   
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8.
本研究的目的是在氯醛糖麻醉、颈动脉窦、主动脉弓去神经和切断迷走神经的猫中探讨室旁核和室旁核α_1肾上腺素受体在刺激肾神经传入纤维引起的升压反应中的作用。刺激肾神经中枢端可引起动脉血压明显升高。这种血压升高由两个成分组成。第一成分可被植物性神经阻断剂六烃季铵和阿托品所阻断,第二成分不能被植物性神经阻断剂所阻断。双侧室旁核毁损后,植物性神经阻断前、后刺激肾神经中枢端引起的升压反应都明显减弱。侧脑室和室旁核微量注射α_1肾上腺素受体拮抗剂哌唑嗪,可显著抑制刺激肾神经传入纤维引起的升压反应。这些结果表明,室旁核和中枢的,尤其在室旁核的α_1肾上腺素受体在刺激肾神经传入纤维引起的升压反应中起重要作用。  相似文献   
9.
Abstract A protein with an M r of 55000 was isolated from glucose-grown Streptococcus faecalis cells. The protein becomes phosphorylated in a phosphoenolpyruvate-dependent reaction catalyzed by enzyme I and HPr of the bacterial phosphotransferase system. It did not stimulate phosphoenolpyruvate-dependent glucose phosphorylation. Several sugars were tested for their ability to dephosphorylate the phosphorylated protein in the presence of membrane fragments. Even though some of the sugars were able to dephosphorylate phospho-HPr quickly, the factor III-like 55-kDa protein remained phosphorylated. We therefore assumed that this protein is not involved in any sugar uptake reaction but that it exerts a regulatory function in Gram-positive bacteria comparable to the function of factor III specific for glucose in Escherichia coli .  相似文献   
10.
Metaphase chromosome bands were induced in Allium flavum (Liliaceae) by protecting the chromosomal DN A with DN A-binding compounds of different base specificities against DNase digestion. The bands obtained represented different subsets of C-band heterochromatin.  相似文献   
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