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41.
Limnology - Despite the reduction in S and N emissions, acid deposition continues to be a problem for the inland water in Northeast Asia. However, catchment-scale studies on acid deposition in the...  相似文献   
42.
The ultrastructure of spermatozoa is a widely accepted source of characters for phylogenetic studies. In this study the fine structure of sperm cells of representatives of six different New and Old World families (Ammotrechidae, Daesiidae, Eremobatidae, Galeodidae, Karschiidae, Solpugidae) of solifuges (Arachnida, Solifugae) were investigated in order to reveal putative characters suitable for subsequent systematic and phylogenetic analyses. The spermatozoa of solifuges represent a relatively simple type of sperm cells. In general, their spermatozoa are roundish, oval shaped (Ammotrechidae, Daesiidae, Eremobatidae, Solpugidae) or plate-shaped (Karschiidae) with or without membrane protuberances and devoid of a flagellum. Only in Galeodidae, very conspicuous thin and elongated sperm cells occur. The spermatozoa either occur as single cells (Eremobatidae, Solpugidae) or in groups of loose knit cells (Ammotrechidae) or in highly ordered groups (Karschiidae). In contrast to the other families studied here, within the Galeodidae and in the genus Blossia (Daesiidae) sperm cells surrounded by a secretion sheath, clearly representing coenospermia, could be observed.  相似文献   
43.
Despite many years of research efforts and continued progress in the identification of urine markers for detection of bladder cancer, none of the markers described to date has been able to replace cystoscopy and urine cytology, the current gold standards for diagnosis. Here, we present a comprehensive gel-based proteomic study in which we have analyzed the presence and origin of fibrinogen (FG) and its degradation products (FDPs) in the urine of patients with and without urothelial carcinoma (UCs), with the aim of evaluating the potential of two-dimensional (2D) gel FDP profiling for detecting bladder cancer. A total of 151 urine samples collected from patients with Ucs of varying degrees of atypia and stages of invasion were compared with a control group consisting of 34 healthy volunteers with no clinical history of bladder cancer. The level and degree of degradation of FG in the urine were determined by 2D gel Western blotting in combination with enhanced chemilumenscence detection. Elevated levels of urine FG/FDPs were found in 99% of patients bearing superficial tumors, in 97% of the cases with early invasive disease, and in 96% of patients with highly invasive tumors. 2D gel profiling of urine FG/FDPs showed that the FG chains exhibited differential susceptibility to in situ proteolysis, with the α-chain being the most susceptible and the γ-chain the most resistant. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry identified peptide sequence regions in several of the most representative and common FDPs, which can be of value for producing novel specific antibodies to detect FG/FDPs in the urine. In addition, we present evidence indicating that FG is not produced by normal or malignant urothelium, although it is present both in the stroma of malignant tissue and tumor lesions. Taken together, the data indicate that increased levels of FG/FDPs amounts in the urine are a characteristic feature of bladder cancer, and emphasize the value of 2D gel profiling of urine FG/FDPs for detecting low-grade, noninvasive UCs.  相似文献   
44.
We have investigated the effects of AgCl and AgNO3 on the Cav3.1 calcium channels stably expressed in the HEK 293 cells. Ca2+ was used as a charge carrier. Both forms of Ag+ blocked the Cav3.1 channel and negatively shifted the I-V relations in a concentration-dependent manner. The inhibition of current amplitude by AgCl was voltage-dependent and increased with increasing amplitude of the depolarizing pulse. Furthermore, AgCl but not AgNO3 accelerated the kinetics of current activation. No effect on current inactivation or steady-state inactivation of the channel was observed for AgCl or AgNO3.  相似文献   
45.
Aging of the human skin is a complex process that consists of chronological and extrinsic aging, the latter caused mainly by exposure to ultraviolet radiation (photoaging). Here we present studies in which we have used proteomic profiling technologies and two-dimensional (2D) PAGE database resources to identify proteins whose expression is deregulated in the epidermis of the elderly. Fresh punch biopsies from the forearm of 20 pairs of young and old donors (21-30 and 75-92 years old, respectively) were dissected to yield an epidermal fraction that consisted mainly of differentiated cells. One- to two-mm3 epidermal pieces were labeled with [35S]methionine for 18 h, lysed, and subjected to 2D PAGE (isoelectric focusing and non-equilibrium pH gradient electrophoresis) and phosphorimage autoradiography. Proteins were identified by matching the gels with the master 2D gel image of human keratinocytes (proteomics.cancer.dk). In selected cases 2D PAGE immunoblotting and/or mass spectrometry confirmed the identity. Quantitative analysis of 172 well focused and abundant polypeptides showed that the level of most proteins (148) remains unaffected by the aging process. Twenty-two proteins were consistently deregulated by a factor of 1.5 or more across the 20 sample pairs. Among these we identified a group of six polypeptides (Mx-A, manganese-superoxide dismutase, tryptophanyl-tRNA synthetase, the p85beta subunit of phosphatidylinositol 3-kinase, and proteasomal proteins PA28-alpha and SSP 0107) that is induced by interferon-gamma in primary human keratinocytes and that represents a specific protein signature for the effect of this cytokine. Changes in the expression of the eukaryotic initiation factor 5A, NM23 H2, cyclophilin A, HSP60, annexin I, and plasminogen activator inhibitor 2 were also observed. Two proteins exhibited irregular behavior from individual to individual. Besides arguing for a role of interferon-gamma in the aging process, the biological activities associated with the deregulated proteins support the contention that aging is linked with increased oxidative stress that could lead to apoptosis in vivo.  相似文献   
46.
Novel and powerful technologies such as DNA microarrays and proteomics have made possible the analysis of the expression levels of multiple genes simultaneously both in health and disease. In combination, these technologies promise to revolutionize biology, in particular in the area of molecular medicine as they are expected to reveal gene regulation events involved in disease progression as well as to pinpoint potential targets for drug discovery and diagnostics. Here, we review the current status of these technologies and highlight some studies in which they have been applied in concert to the analysis of biopsy specimens.  相似文献   
47.
48.
Journal of Evolutionary Biochemistry and Physiology - The aim of the work was to conduct a retrospective analysis of the clinical data of patients with pneumonia caused by the SARS-CoV-2 virus, and...  相似文献   
49.
Care of the young by male and female common voles reared by both parents (complete families) or by females only (incomplete families) has been studied. It has emerged that the absence of an adult male in the common vole family groups, reducing the care of young (first and foremost, tactile stimulation), negatively influences their pair bonds and the subsequent parental behavior of the male offspring.  相似文献   
50.
The naked mole‐rat (Heterocephalus glaber) is used as an animal model in various studies, but not much is known on the genetic diversity of this animal. Here, on the basis of dataset collected from the most part of the distribution range of the naked mole‐rat, we reconstruct phylogenetic relationships between its different lineages using mitochondrial and nuclear markers. We also mapped the distribution of the main genetic lineages, dated the divergence using different Bayesian tree‐calibration techniques, and modeled the distribution of ecological niches for the period of last glacial maximum. Our results show the existence of two deeply divergent clades designated as the eastern clade (East Ethiopia) and the southern clade (South Ethiopia and North Kenya). Additional phylogeographic structure was demonstrated for each of these two clades. Divergence between these two main lineages dated back to the Middle Pleistocene (ca. 1.4–0.8 Mya) and may have been related to climate changes in Africa during the Mid‐Pleistocene Revolution. In light of substantial genetic differences between the eastern and southern lineages of the naked mole‐rat, these two clades can be considered as two deeply divergent subspecies or even as distinct species.  相似文献   
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