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1.
Testicular development in the adult male F1 sturgeon hybrid, the bester ( Huso huso L. female x Acipenser ruthenus L. male), was examined monthly in relation to serum sex steroid levels. Spermatogenesis lasted for 1 year, with meiosis generally starting in September and spermiogenesis in November, although there was considerable variation in testicular developmental stages between fish sampled monthly. Testicular development continued, slowly, during the winter months until April. Fish did not exhibit spontaneous spermiation, and phagocytotic activity of Sertoli cells became prominent from May onwards. Androgen levels increased during Spermatogenesis and remained high throughout the pre-spermiation period. In the degeneration stage, 11-ketotestosterone concentrations declined to low levels, while testoster- one levels remained high. The serum concentration of 17,20β-dihydroxy-4-pregnen-3-one was low throughout the reproductive cycle. Based on these results, it is suggested that the time appropriate for induction of final maturation would be from November–December to April when the testes are in the late stage of development.  相似文献   
2.
Absorption and imagery locate immune responses in the body   总被引:2,自引:0,他引:2  
Imagery instructions specifying mucosal immunity should alter mucosal immunoglobulin A (m-IgA) levels in high absorbers, whose intent concentration evokes intense physiological responses. After screening for health status, 121 high or low absorbers were randomly assigned to either Relaxation Alone (R), Relaxation with Mucosal Immune Imagery (RI), or Vigilance Task control (VT). Before and after one 60-min intervention, subjects reported theory-relevant psychological variables and provided 5ml whole saliva, which was immediately frozen and assayed lateren masse with enzyme-linked immunoabsorbence (ELISA). MANOVA analysis of psychological variables replicated past research. ANOVA on residualized m-IgA found Time × Absorption interaction and Condition main effects. High more than low absorbers responded to relaxation with mucosal immune imagery by producing higher m-IgA. High absorbers appear able to locate where their immune systems will respond. Individual differences like absorption level need to be emphasized in diagnosis and treatment responsiveness.National Institutes of HealthM. Banks (Jasnoski) Gregerson, Department of Psychology, The George Washington University, changed to The Family Therapy Institute; Ingram M. Roberts, The George Washington University Medical Center, changed to Department of Medicine, Bridgeport Hospital; and Michael M. Amiri, The George Washington University Medical Center, changed to the Department of Neuroscience, NINDS Branch, National Institutes of Health. This research supported by an intra-mural BioMedical Research Grant from The George Washington University, was presented at the 1992 Annual Meeting of the Eastern Psychological Association, Boston, Massachusetts. Special thanks are extended to the following students who assisted instrumentally at various stages: undergraduates Lina Alathari, S. Theodor King, Beth Lieberman, Parisa Lotfi, Anita McClenon, and Karen Siscoe, and graduate student Mariken Hasert.  相似文献   
3.
Twenty three fused carbazole–imidazoles 6a–w were designed, synthesized, and screened as new α-glucosidase inhibitors. All the synthesized fused carbazole-imidazoles 6a-w were found to be more active than acarbose (IC50?=?750.0?±?1.5?µM) against yeast α-glucosidase with IC50 values in the range of 74.0?±?0.7–298.3?±?0.9?µM. Kinetic study of the most potent compound 6v demonstrated that this compound is a competitive inhibitor for α-glucosidase (Ki value?=?75?µM). Furthermore, the in silico studies of the most potent compounds 6v and 6o confirmed that these compounds interacted with the key residues in the active site of α-glucosidase.  相似文献   
4.
In this study, concentration of mercury was determined in the trophic levels of benthic, benthopelagic, pelagic fish species, and river birds from Arvand River, located in the Khuzestan province in the lowlands of southwestern Iran at the head of the Persian Gulf. The order of mercury concentrations in tissues of the fish species was as follows: liver>gill>muscle and in tissues of the kingfisher species was as follows: feather>liver>kidney>muscle. Therefore, liver in fish and feather in kingfisher exhibited higher mercury concentration than the other tissues. There was a positive correlation between mercury concentrations in fish and kingfisher species with size of its food items. We expected to see higher mercury levels in tissues of female species because they are larger and can eat larger food items. The results of this study show that the highest mean mercury level were found in the kingfisher (Anas crecca), followed by benthic (Epinephelus diacanthus), benthopelagic (Chanos chanos), and pelagic fish (Strongylura strongylura). Mean value of mercury in fish species, S. strongylura were (0.61 μg g?1 dry weight), C. chanos (0.45 μg g?1 dry weight), E. diacanthus (0.87 μg g?1 dry weight), and in kingfisher species A. crecca was (2.64 μg g?1 dry weight). Significant correlation between mercury concentration in fish and kingfisher may be related to high variability of mercury in the fish.  相似文献   
5.
International Journal of Peptide Research and Therapeutics - LL-37 is a 37 amino acid long cationic peptide belonging to the cathelicidin family of antimicrobial peptides. Limited investigations...  相似文献   
6.

Colloidal nanoparticles (NPs) interact with biological fluids such as human plasma to form a protein coating (corona) on the surface of NPs (NP-protein complex). However, the impact of size and type of NPs on binding of the hard corona to the surface of NPs as well as damping of their optical spectra has not been systematically explored. To elucidate the interaction between biological environment (human plasma) and NPs, a photophysical measurement was conducted to quantify the interaction of two different types of NPs (gold (Au) and silver (Ag)) with common human plasma proteins. The colloidal AuNPs and AgNPs were electrostatically stabilized and varied in diameter from 10 to 80 nm in the presence of common human plasma. The sizes of the NPs were determined using transmission electron microscopy (TEM). Optical absorption spectra were obtained for the complexes. Dynamic light scattering (DLS) measurement and zeta potential were used to characterize the sizes, hydrodynamic diameters, and surface charges of the protein-NPs complexes. Protein separation was performed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to isolate and identify the protein bands. The absorption of proteins to the NPs was found to be strongly dependent on the size and type of NPs. The distance between surface of NPs by absorbed protein bound to the NPs gradually increased with size of NPs, particularly for AgNPs with primary diameter of < 50 nm. The chi-square test proved that AgNPs are a good candidate in sensing the protein complex in human plasma compared with AuNPs mainly for the AgNPs with diameter sized 50 nm.

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7.

We propose the use of the electron cloud generated by quasi-particle waves called polariton dipoles, which oscillated within a silicon microring-embedded gold grating system for quantum consciousness processing model. An embedded gold grating is coupled by a whispering gallery mode beam generated by a soliton pulse, from which the polariton waves oscillated with the plasma frequency at the Bragg wavelength. The excited polariton cloud by the external stimuli can be detected at the system output ports. The two states of the polariton (electron) are spin-up and spin-down that can process automatically and deliver to the network and cloud. In manipulation, the results obtained show the electron density increased by increasing the input power into the system. In application, the cell polariton cloud coupled by the external stimuli and patterned by the quantum cellular automata results, which localized in the cloud network and connected to the nerve cell access nodes. The coded polaritons connected to the nerve cell memory clouds, while the required commands are delivered to resonant cells via the network link. More stenographic codes can also be generated by other external stimuli sources, which can process similarly.

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8.

Noble metals, especially Ag and Au nanostructures, have unique and adjustable optical attributes in terms of surface plasmon resonance. In this research, the effect of Ag and Au nanoparticles with spherical and rod shapes on the light extraction efficiency and the FWHM of OLED structures was investigated using the finite difference time domain (FDTD) method. The simulation results displayed that by changing the shape and size of Ag and Au nanostructures, the emission wavelength can be adjusted, and the FWHM can be reduced. The presence of Ag and Au nanoparticles in the OLEDs showed a blue and red shift of the emission wavelength, respectively. Also, the Ag and Au nanorods caused a significant reduction in the FWHM and a shift to the longer wavelengths in the structures. The structures containing Ag nanorods showed the narrowest FWHM and longer emission wavelength than the other structures.

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9.
Diabetic retinopathy (DR), a leading cause of vision loss and a significant source of morbidity, is the most common ocular complication of prolonged diabetes mellitus. Most therapeutic approaches address DR by preventing or destroying neovasculature; however, this fails to eliminate pathogenic causes. Mesenchymal stem cells (MSCs) are a promising candidate for cell therapy because they have unique regenerative potential and provide an option to manage retinal injuries. Transplantation of MSCs in rats with diabetes induced by streptozocin administration was shown to ameliorate DR. However, the poor viability and homing of MSCs after transplantation may reduce the efficacy of cell therapy. Intravitreal transplantation of MSCs was shown to augment vascular endothelial growth factor (VEGF). More recent studies have found a central role for VEGF in vascular lesion formation in DR and proposed blockage of VEGF as an effective approach to manage DR. Atorvastatin, a 3-hydroxy-3-methyl-glutaryl coenzyme A reductase inhibitor, has been proven to decrease VEGF production of MSCs under hypoxic conditions. It has also been demonstrated that atorvastatin increases the viability of MSCs through the adenosine monophosphate-activated protein kinase-endothelial nitric oxide synthase signaling pathway. There is also evidence that nitric oxide improves homing of MSCs by increasing chemokine-related receptor CXCR4 expression. It could be hypothesized that co-administration of MSCs with atorvastatin may be a significant step forward in development of an efficient MSC therapy of DR through preventing excess VEGF production by MSCs under hypoxic conditions as well as increasing the viability and homing of transplanted MSCs.  相似文献   
10.
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