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991.
Molecular Biology Reports - Benign metastasizing leiomyoma (BML) is a rare disease characterized by extrauterine benign leiomyomatosis in patients with a previous or concomitant history of uterine...  相似文献   
992.
The plant hormone abscisic acid (ABA) is present and active in humans, regulating glucose homeostasis. In normal glucose tolerant (NGT) human subjects, plasma ABA (ABAp) increases 5-fold after an oral glucose load. The aim of this study was to assess the effect of an oral glucose load on ABAp in type 2 diabetes (T2D) subjects. We chose two sub-groups of patients who underwent an oral glucose load for diagnostic purposes: i) 9 treatment-naive T2D subjects, and ii) 9 pregnant women with gestational diabetes (GDM), who underwent the glucose load before and 8–12 weeks after childbirth. Each group was compared with matched NGT controls. The increase of ABAp in response to glucose was found to be abrogated in T2D patients compared to NGT controls. A similar result was observed in the women with GDM compared to pregnant NGT controls; 8–12 weeks after childbirth, however, fasting ABAp and ABAp response to glucose were restored to normal in the GDM subjects, along with glucose tolerance. We also retrospectively compared fasting ABAp before and after bilio-pancreatic diversion (BPD) in obese, but not diabetic subjects, and in obese T2D patients, in which BPD resulted in the resolution of diabetes. Compared to pre-BPD values, basal ABAp significantly increased 1 month after BPD in T2D as well as in NGT subjects, in parallel with a reduction of fasting plasma glucose. These results indicate an impaired hyperglycemia-induced ABAp increase in T2D and in GDM and suggest a beneficial effect of elevated ABAp on glycemic control.  相似文献   
993.
In the search for a durable pest control management, biological control agents and photoselective covers are suitable candidates to be implemented in greenhouse crops. In this work, we studied the effects of a 50 mesh photoselective cover compared to a standard with similar characteristics but without UV-absorbing additives on the performance of Aphidius ervi Haliday (Hymenoptera: Braconidae), a widely used parasitoid to control aphids in vegetable crops. Four field experiments were conducted in La Poveda Experimental Farm (Central Spain) where a lettuce crop was grown during the years 2008–2010. Lettuce plants were infested by Macrosiphum euphorbiae (Thomas) (Hemiptera: Aphididae) and the parasitoid A. ervi was released and monitored throughout the crop cycle to evaluate any constraint in its performance produced by UV-absorbing nets. The ability of A. ervi to find and parasitize the host was not modified by the photoselective cover during the four seasons studied. Thus, we suggest that both strategies could be combined in the context of IPM in vegetable crops where this natural enemy is released.  相似文献   
994.
We propose to model the functional architecture of the primary visual cortex V1 as a principal fiber bundle where the two-dimensional retinal plane is the base manifold and the secondary variables of orientation and scale constitute the vertical fibers over each point as a rotation–dilation group. The total space is endowed with a natural symplectic structure neurally implemented by long range horizontal connections. The model shows what could be the deep structure for both boundary and figure completion and for morphological structures, such as the medial axis of a shape.  相似文献   
995.
Summary Kidneys of adult male and female lizards were studied by electron microscopy, in order to understand the ultrastructure of the collecting duct and a differentiated part thereof, the sexual segment, which is an important accessory sexual organ. First portion of sexual segment in males: The cells are filled with large secretory granules of a wide range of opacities. The granular endoplasmic reticulum is abundant; basal formations of superimposed flat cisternae are frequent. Distended vesicles and microvesicles prevail in the supranuclear, well developed Golgi apparatus. Evidences indicate that secretion of these cells is holocrine. Second portion of sexual segment in males: All of the secretory granules are apical in location and relatively electron-opaque; they show a denser core. This core is formed by a substance which, after lying in contact with ribosomes, enters the secretory vesicles of the highly developed Golgi apparatus. A lighter substance is then condensed around it. The secretion of the granules is merocrine. The granular endoplasmic reticulum is very abundant in these cells, but basal ergastoplasmic formations are lacking. Sexual segment in females: The cells show features similar to those of the male first portion, but they are smaller. Undifferentiated collecting duct: Most of the cells are mucigenic. They have small ovoid, apical secretory granules. The density of the granules varies from cell to cell; when they are electron-lucent, they exhibit laminar or dotted opaque figures. Moderately developed Golgi apparatus and granular endoplasmic reticulum, as well as elongated mitochondria, occur in mucigenic cells. Intercalated among the latter are non-secretory cells. They have very abundant mitochondria, numerous microvilli, many pinocytic and smooth-membrane vesicles, whereas the organelles participating in synthetic processes are poorly developed; their function is most likely related to active solute transport.  相似文献   
996.
997.
Notothenioidei, the taxonomic group of teleosts that dominates the Southern Ocean and dwell in the Ross Sea at large, provide an example of marine species that underwent unique adaptations to life at low temperatures and high oxygen concentrations, resulting in morphological, physiological, genomic, and biochemical peculiarities in comparison with warm-water fish. Global Warming raises concerns over the fate of these stenothermal fish, as their adaptation has been accompanied by irreversible genomic losses, which suggest a poor genetic potential to adapt to warmer climates. Specifically, this review focuses on adaptation of proteins belonging to the globin superfamily, which include the respiratory proteins hemoglobin and myoglobin and the non-respiratory proteins neuroglobin and cytoglobin. Here, we describe their molecular adaptations to cold temperatures in the framework of the physiology of oxygen transport and management of oxidative stress in fish species largely populating the Ross Sea.  相似文献   
998.
999.
The developmental competence of bovine oocytes meiotically arrested with specific cdk2 inhibitor roscovitine was studied. After removal of the 32-h block with roscovitine, 82.7 +/- 5.4% reached the metaphase II stage at the end of maturation, which was lower than in controls (96.3 +/- 1.3%, p < 0.001). The process of polar body formation started at 11 h of maturation in the roscovitine group, that is 4 h earlier than in controls and its kinetics was quite similar to controls up to 16 h of maturation, when nearly 70% of oocytes extruded their polar bodies. The rate of blastocyst formation of roscovitine oocytes and their cell number after IVF, parthenogenetic activation, and nuclear transfer (NT) were equal to controls, which demonstrates the possibility of artificially maintaining bovine oocytes in the GV stage for 32 h without altering their preimplantation developmental competence. This approach can be very useful for the management of an NT program where enucleated oocytes are required at specific times or locations.  相似文献   
1000.
hGTSE-1 (human G(2) and S phase-expressed-1) is a cell cycle-regulated protein mainly localized in the cytoplasm and apparently associated with the microtubules. hGTSE-1 is able to down-regulate levels and activity of the p53 tumor suppressor protein: it binds the C-terminal region of p53 and represses its ability to induce apoptosis after DNA damage. Here we report that, after DNA damage, hGTSE-1 becomes stabilized in a p53-independent way and accumulated in the nucleus. Further characterization of hGTSE-1 localization revealed increased nuclear staining in unstressed cells after treatment with the nuclear export inhibitor leptomycin B, or when a nuclear export signal (NES) located in its C-terminal region was mutated. Finally, we provide evidence that hGTSE-1 ectopic expression, in addition to p53 protein levels down-regulation, is able to enhance cytoplasmic localization of p53. Interestingly, NES-mutated hGTSE-1 accumulates in the nucleus, binds p53 but looses its ability to enhance cytoplasmic redistribution of p53 and to regulate p53 protein levels. Similarly, when wild type hGTSE-1 functions on p53 were analyzed in cells lacking Mdm2, it failed in regulating both p53 localization and protein levels, thus indicating that hGTSE-1 requires an intact NES and functional Mdm2 for the regulation of p53. Our results provide new insights into the mechanism of hGTSE-1 function, whereby its characterized nucleo-cytoplasmic shuttling ability is required to regulate p53.  相似文献   
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