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beta-glucuronidase, cathepsin D, acid and alkaline phosphatases were studied in rhesus monkey endometrium during the menstrual cycle (day -6 to day +10) and pre-implantation stages (day +3 to day +6) of gestation, with day 0 considered as the day of ovulation. Acid hydrolases exhibited low levels in proliferative phase endometria followed by their gradual rise in the secretory phase of the menstrual cycle. Despite no shifts in the levels of serum progesterone and estradiol-17 beta, the pre-implantation period was, however, associated with distinct changes in enzyme profiles characterized by lower absolute levels (P less than 0.05) of acid phosphatase and beta-glucuronidase on days 3 to 6 of gestation, whereas cathepsin D activity declined significantly (P less than 0.05) on days 5 and 6. Alkaline phosphatase showed a characteristic rise during the pre-ovulatory period with a gradual lowering of its level in post-ovulatory phase endometria of a non-fertile cycle; in contrast, during early gestation, alkaline phosphatase activity showed a marked elevation (P less than 0.05) on days 5 and 6 of gestation. The significance of these findings is discussed.  相似文献   
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To evaluate the effect of Er:YAG etching on topography, microstructure, compressive strength, and shear bond strength (SBS) of All-Bond Universal adhesive  相似文献   
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Abstract Vaginal bacterial communities play an important role in human health and have been shown to influence HIV infection. Pigtailed macaques (Macaca nemestrina) are used as an animal model of HIV vaginal infection of women. Since the bacterial microbiota could influence retrovirus infection of pigtailed macaques, the genital microbiota in 10 cycling macaques was determined by pyrosequencing. The microbiota of all macaques was polymicrobial with a median of 13 distinct genera. Strikingly, the genera Sneathia and Fusobacterium, both in the phylum Fusobacteria, accounted for 18.9% and 13.3% of sequences while the next most frequent were Prevotella (5.6%), Porphyromonas (4.1%), Atopobium (3.6%), and Parvimonas (2.6%). Sequences corresponding to Lactobacillus comprised only 2.2% of sequences on average and were essentially all L. amylovorus. Longitudinal sampling of the 10 macaques over an 8-week period, which spanned at least one full ovulatory cycle, showed a generally stable presence of the major types of bacteria with some exceptions. These studies show that the microbiota of the pigtailed macaques is substantially dissimilar to that found in most healthy humans, where the genital microbiota is usually dominated by Lactobacillus sp. The polymicrobial makeup of the macaque bacterial populations, the paucity of lactobacilli, and the specific types of bacteria present suggest that the pigtailed macaque microbiota could influence vaginal retrovirus infection.  相似文献   
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We have established a model that shows cooperative interaction among preimplantation embryos and the role of growth factors on their development and growth. Two-cell mouse embryos cultured singly in 25-microliters microdrops had inferior development to blastocysts and lower cell numbers per blastocyst compared with those cultured in groups of 5 or 10. The inferior development of singly cultured embryos was markedly improved by addition of epidermal growth factor (EGF) or transforming growth factor alpha or beta 1 (TGF-alpha or TGF-beta 1) to the culture medium. The stage of embryonic development, primarily affected by these treatments, was between eight-cell/morula and blastocyst. Furthermore, blastocysts developed from eight-cell embryos cultured in groups or singly in the presence of EGF showed a higher incidence of zona hatching compared with those cultured singly in the absence of EGF. Detection of EGF receptors on the embryonic cell surface at eight-cell/morula and blastocyst stages suggests beneficial effects of EGF or TGF-alpha on preimplantation embryo development and blastocyst functions. Insulin-like growth factor I (IGF-I) had no influence on embryo development. To further document the cooperative interactions among embryos, the volume of the culture medium was doubled to 50 microliters. This increase in culture volume was even more detrimental to the development of singly cultured embryos. However, this detrimental effect was significantly reversed by EGF and reversed even more markedly by a combination of EGF and TGF-beta 1 but not by TGF-beta 1 alone. Although TGF-beta 1 plus IGF-I caused a modest improvement of embryo development, the response was not as great as shown by EGF alone. Furthermore, IGF-I had no additive effect on EGF-induced embryonic development. The study presents clear evidence that specific growth factors of embryonic and/or reproductive tract origin participate in preimplantation embryo development and blastocyst functions in an autocrine/paracrine manner.  相似文献   
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Mammalian fertility absolutely depends on synchronized development of the blastocyst to the stage when it is competent to implant, and the uterus to the stage when it is receptive to implantation. However, the molecular basis for the reciprocal interaction between the embryo and the uterus remains largely unexplored. One potentially important mechanism involves signaling between an evolutionarily conserved G protein-coupled protein cannabinoid receptor, CB1, that is expressed at high levels on the surface of the trophectoderm and anandamide (N-arachi-donoylethanolamine), an endocannabinoid ligand found to be produced at higher levels by the uterus before implantation and then down-regulated at the time of implantation. Using genetic, pharmacological, and physiological approaches, we show here that anandamide within a very narrow range regulates blastocyst function and implantation by differentially modulating mitogen-activated protein kinase signaling and Ca2+ channel activity via CB1 receptors. Anandamide at a low concentration (7 nM) induces extracellular regulated kinase phosphorylation and nuclear translocation in trophectoderm cells without influencing Ca2+ channels, and renders the blastocyst competent for implantation in the receptive uterus. In contrast, anandamide at a higher concentration (28 nM) inhibits Ca2+ channel activity and blastocyst competency for implantation without influencing mitogen-activated protein kinase signaling. Besides uncovering a potentially important regulatory mechanism for synchronizing blastocyst and uterine competency to implantation, this observation has high clinical relevance, because elevated levels of anandamide induce spontaneous pregnancy loss in women.  相似文献   
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Stingrays are common inhabitants in the northern waters of the Persian Gulf and Oman Sea. In the present study, the clinical aspects of injuries induced in three patients bitten by stingrays in Hormozgan province waters were first examined. The LD50 of crude venom extract obtained from the most common stingray in Hormozgan province (Himantura gerrardi) was then estimated by up-and-down dosing and double dose methods in mice. Third and finally, the cardiac symptoms induced by injection of the extract from the venomous spines were evaluated in rats. Intense pain was noticed in all human cases. Redness was observed in two cases, and spasm and seizure were each recorded in only one case. LD50 of the venom extract in mice was about 100 mg kg−1. The observed cardiac symptoms in rats included an increase in pulse rate and various changes in electrocardiogram (ECG) parameters such as T and Q values, and PR and RR intervals.  相似文献   
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Agonist-induced Ca(2+) entry via store-operated Ca(2+) (SOC) channels is suggested to regulate a wide variety of cellular functions, including salivary gland fluid secretion. However, the molecular components of these channels and their physiological function(s) are largely unknown. Here we report that attenuation of SOC current underlies salivary gland dysfunction in mice lacking transient receptor potential 1 (TRPC1). Neurotransmitter-regulated salivary gland fluid secretion in TRPC1-deficient TRPC1(-/-) mice was severely decreased (by 70%). Further, agonist- and thapsigargin-stimulated SOC channel activity was significantly reduced in salivary gland acinar cells isolated from TRPC1(-/-) mice. Deletion of TRPC1 also eliminated sustained Ca(2+)-dependent potassium channel activity, which depends on Ca(2+) entry and is required for fluid secretion. Expression of key proteins involved in fluid secretion and Ca(2+) signaling, including STIM1 and other TRPC channels, was not altered. Together, these data demonstrate that reduced SOC entry accounts for the severe loss of salivary gland fluid secretion in TRPC1(-/-) mice. Thus, TRPC1 is a critical component of the SOC channel in salivary gland acinar cells and is essential for neurotransmitter-regulation of fluid secretion.  相似文献   
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