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991.
Inhibin activity in goat seminal plasma was measured by in vitro assay throughout successive 9 months and its relationship with the serum FSH, LH and testosterone concentrations was investigated. Total inhibin activity (TIA) in seminal plasma gradually increased from spring to summer, reduced in autumn (P<0.05) and recovered toward winter (P<0.05). Serum FSH and LH reached a peak in mid-summer (P<0.01) and returned to the low levels in autumn. Serum testosterone also increased in mid-summer and kept the high levels until the early winter (P<0.05). Some positive correlation was found in monthly levels between seminal TIA and serum FSH (r=0.305; P<0.05). Results suggest that the summer increase of inhibin activity in seminal plasma relates with the mid-summer rise of serum FSH levels in the male goat. 相似文献
992.
Pairs of neurons were differentially stained by intracellular injection of the divalent cations, nickel and cobalt. Pairs of neuronal tracts could be similarly labelled following immersion of their axon bundles in the markers described. Use of nickel and a 4 : 6 mixture of cobalt and nickel according to the protocols presented here revealed the morphology of cricket neuron processes as thin as 1 μm in diameter and yielded a favourable contrast between the cells marked, as well as with respect to the background of unstained tissue. 相似文献
993.
Johnson L Kim HK Tanabe M Gorcsan J Schwartzman D Shroff SG Pinsky MR 《American journal of physiology. Heart and circulatory physiology》2007,293(5):H3046-H3055
The goal of the present study was to assess the effects of left ventricular (LV) pacing sites (apex vs. free wall) on radial synchrony and global LV performance in a canine model of contraction dyssynchrony. Ultrasound tissue Doppler imaging and hemodynamic (LV pressure-volume) data were collected in seven anesthetized, opened-chest dogs. Right atrial (RA) pacing served as the control, and contraction dyssynchrony was created by simultaneous RA and right ventricular (RV) pacing to induce a left bundle-branch block-like contraction pattern. Cardiac resynchronization therapy (CRT) was implemented by adding simultaneous LV pacing to the RV pacing mode at either the LV apex (CRTa) or free wall (CRTf). A new index of synchrony was developed via pair-wise cross-correlation analysis of tissue Doppler radial strain from six midmyocardial cross-sectional regions, with a value of 15 indicating perfect synchrony. Compared with RA pacing, RV pacing significantly decreased radial synchrony (11.1 +/- 0.8 vs. 4.8 +/- 1.2, P < 0.01) and global LV performance (cardiac output: 2.0 +/- 0.3 vs. 1.4 +/- 0.1 l/min and stroke work: 137 +/- 22 vs. 60 +/- 14 mJ, P < 0.05). Although both CRTa and CRTf significantly improved radial synchrony, only CRTa markedly improved global function (cardiac output: 2.1 +/- 0.2 l/min and stroke work: 113 +/- 13 mJ, P < 0.01 vs. RV pacing). Furthermore, CRTa decreased LV end-systolic volume compared with RV pacing without any change in LV end-systolic pressure, indicating an augmented global LV contractile state. Thus, LV apical pacing appears to be a superior pacing site in the context of CRT. The dissociation between changes in synchrony and global LV performance with CRTf suggests that regional analysis from a single plane may not be sufficient to adequately characterize contraction synchrony. 相似文献
994.
For the first step toward resolution of the higher-level relationships of the order Aulopiformes (Teleostei: Eurypterygii)
using longer DNA sequences, we determined the complete mitochondrial DNA sequence for Aulopus japonicus (Aulopodidae). The entire genome was purified by gene amplification using a long PCR technique, and the products were subsequently
used as templates for PCR with 63 fish-versatile and 3 species-specific primers that amplify contiguous, overlapping segments
of the entire genome. Direct sequencing of the PCR products demonstrated that the genome (16 653 base pairs [bp]) contained
the same 37 mitochondrial genes (2 ribosomal RNA, 22 transfer RNA, and 13 protein-coding genes) as found in other vertebrates,
with the gene order identical to that in typical vertebrates. Maximum-parsimony analysis using nucleotide sequences from the
concatenated 12 protein-coding genes (no third codon positions and excluding the ND6 gene) plus 22 tRNA genes (stem regions
only) from eight teleosts placed A. japonicus in a reasonable phylogenetic position; those from individual protein-coding genes and the concatenated 22 tRNA genes alone,
however, did not reproduce the expected phylogeny with few exceptions, probably owing to insufficient phylogenetic information
in these smaller data sets. This result suggests that further taxonomic sampling and sequencing efforts may clarify limits
and intra- and interrelationships of this morphologically and ecologically diverse group of fishes using mitochondrial genomic
(mitogenomic) data.
Received: August 31, 2000 / Revised: December 20, 2000 / Accepted: January 23, 2001 相似文献
995.
Kashiwagi S Iwamoto-Kihara A Kojima M Nonaka T Futai M Nakanishi-Matsui M 《Biochemical and biophysical research communications》2008,365(2):227-231
A complex of γ, ε, and c subunits rotates in ATP synthase (FoF1) coupling with proton transport. Replacement of βSer174 by Phe in β-sheet4 of the β subunit (βS174F) caused slow γ subunit revolution of the F1 sector, consistent with the decreased ATPase activity [M. Nakanishi-Matsui, S. Kashiwagi, T. Ubukata, A. Iwamoto-Kihara, Y. Wada, M. Futai, Rotational catalysis of Escherichia coli ATP synthase F1 sector. Stochastic fluctuation and a key domain of the β subunit, J. Biol. Chem. 282 (2007) 20698-20704]. Modeling of the domain including β-sheet4 and α-helixB predicted that the mutant βPhe174 residue undergoes strong and weak hydrophobic interactions with βIle163 and βIle166, respectively. Supporting this prediction, the replacement of βIle163 in α-helixB by Ala partially suppressed the βS174F mutation: in the double mutant, the revolution speed and ATPase activity recovered to about half of the levels in the wild-type. Replacement of βIle166 by Ala lowered the revolution speed and ATPase activity to the same levels as in βS174F. Consistent with the weak hydrophobic interaction, βIle166 to Ala mutation did not suppress βS174F. Importance of the hinge domain [phosphate-binding loop (P-loop)/α-helixB/loop/β-sheet4, βPhe148-βGly186] as to driving rotational catalysis is discussed. 相似文献
996.
Kamamoto Naoya Tano Taishi Fujimoto Koichi Shimamura Masaki 《Journal of plant research》2021,134(3):457-473
Journal of Plant Research - The spiral arrangement (phyllotaxis) of leaves is a shared morphology in land plants, and exhibits diversity constrained to the Fibonacci sequence. Phyllotaxis in... 相似文献
997.
Reira Suzuki Takashi Ueda Takuji Wada Masaki Ito Takashi Ishida Shinichiro Sawa 《Plant Biotechnology》2021,38(1):1
Root-knot nematodes (RKN; Meloidogyne incognita) are phytoparasitic nematodes that cause significant damage to crop plants worldwide. Recent studies have revealed that RKNs disrupt various physiological processes in host plant cells to induce gall formation. However, little is known about the molecular mechanisms of gall formation induced by nematodes. We have previously found that RNA expression levels of some of genes related to micro-RNA, cell division, membrane traffic, vascular formation, and meristem maintenance system were modified by nematode infection. Here we evaluated these genes importance during nematode infection by using Arabidopsis mutants and/or β-glucronidase (GUS) marker genes, particularly after inoculation with nematodes, to identify the genes involved in successful nematode infection. Our results provide new insights not only for the basic biology of plant–nematode interactions but also to improve nematode control in an agricultural setting. 相似文献
998.
Kun Joong Kim Moran Balaish Masaki Wadaguchi Lingping Kong Jennifer L. M. Rupp 《Liver Transplantation》2021,11(1):2002689
The introduction of new, safe, and reliable solid-electrolyte chemistries and technologies can potentially overcome the challenges facing their liquid counterparts while widening the breadth of possible applications. Through tech-historic evolution and rationally analyzing the transition from liquid-based Li-ion batteries (LIBs) to all-solid-state Li-metal batteries (ASSLBs), a roadmap for the development of a successful oxide and sulfide-based ASSLB focusing on interfacial challenges is introduced, while accounting for five parameters: energy density, power density, longterm stability, processing, and safety. First taking a strategic approach, this review dismantles the ASSLB into its three major components and discusses the most promising solid electrolytes and their most advantageous pairing options with oxide cathode materials and the Li metal anode. A thorough analysis of the chemical, electrochemical, and mechanical properties of the two most promising and investigated classes of inorganic solid electrolytes, namely oxides and sulfides, is presented. Next, the overriding challenges associated with the pairing of the solid electrolyte with oxide-based cathodes and a Li-metal anode, leading to limited performance for solid-state batteries are extensively addressed and possible strategies to mitigate these issues are presented. Finally, future perspectives, guidelines, and selective interface engineering strategies toward the resolution of these challenges are analyzed and discussed. 相似文献
999.
1000.
The latitudinal decline of species richness is a general spatial pattern of biodiversity, and it applies to marine species as well. Based on a latitudinal gradient of marine species richness, potential stocks of marine ecosystem services are expected to be higher in lower latitudes through increment in biodiversity. However, little is known about the relationships of the marine ecosystem services with latitude and biodiversity. We estimated the latitudinal patterns and relationships with the biodiversity of potential stocks of three major reef fish-based ecosystem services (fisheries production, aquarium fish production, and recreational diving) at ten coral habitats from tropical to temperate zones in the Kuroshio Current region (8°37′N–33°24′N) using field survey data and information from relevant websites and administrative statistics. We found a latitudinal declin from south to north in potential stocks of aquarium fish production and diving in this region, whereas the peaks of fisheries production were found around both tropical and sub-tropical zones. Our results also showed strong positive effects of biodiversity on potential stocks of the three ecosystem services, highlighting the importance of conserving diverse fish species to sustain multiple services at high levels. Broad spatial patterns of the reef fish-based ecosystem services are useful as baselines for future evaluation of their changes. As the effects of climate change on reef fishes are predicted to vary among different latitude zones, our estimates of the ecosystem services infer specific management and economic actions for the respective zones against climate change. 相似文献