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1.
Ruxandra Ion L. Telvi Jean-Louis Chaussain Jacques Patrick Barbet Manoel Nunes Anne Safar Marie-Odile Réthoré Marc Fellous Ken McElreavey 《Human genetics》1998,102(2):151-156
In 46,XY individuals, testes are determined by the activity of the SRY gene (sex-determining region Y), located on the short arm of the Ychromosome. The other genetic components of the cascade
that leads to testis formation are unknown and may be located on the Xchromosome or on the autosomes. Evidence for the existence
of several loci associated with failure of male sexual development is indicated by reports of 46,XY gonadal dysgenesis associated
with structural abnormalities of the Xchromosome or of autosomes (chromosomes9, 10, 11 and 17). In this report, we describe
the investigation of a child presenting with multiple congenital abnormalities, mental retardation and partial testicular
failure. The patient had a homogeneous de novo 46,XY,inv dup(9)(pter→p24.1::p21.1 →p23.3::p24.1→qter) chromosome complement.
No deletion was found by either cytogenetic or molecular analysis. The SRY gene and DSS region showed no abnormalities. Southern blotting dosage analysis with 9p probes and fluorescent in situ hybridisation data
indicated that the distal breakpoint of the duplicated fragment was located at 9p24.1, proximal to the SNF2 gene. We therefore suggest that a gene involved in normal testicular development and/or maintenance is present at this position
on chromosome 9.
Received: 20 January 1997 / Accepted: 5 November 1997 相似文献
2.
Barreto da Silveira Ismênia Glauce de Oliveira da Silva Neto Jorge Alves da Silva Ferreira Jéssica Silva Tatiane Severo Holanda Ioná Santos Araújo 《Molecular biology reports》2021,48(10):6887-6895
Molecular Biology Reports - Leprosy is a chronic infectious disease caused by Mycobacterium leprae and persists as a serious public health problem in Brazil. This microorganism is inculturable,... 相似文献
3.
George Nicolae Daniel Ion George Mihai Nitulescu Costin Ioan Popescu 《Bioorganic & medicinal chemistry letters》2019,29(18):2527-2534
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), also known as Apo2L, has been investigated in the past decade for its promising anticancer activity due to its ability to selectively induce apoptosis in tumoral cells by binding to TRAIL receptors (TRAIL-R). Macromolecules such as agonistic monoclonal antibodies and recombinant TRAIL have not proven efficacious in clinical studies, therefore several small molecules acting as TRAIL-R agonists are emerging in the scientific literature. In this work we focus on systemizing these drug molecules described in the past years, in order to better understand and predict the requirements for a novel anti-tumoral therapy based on the TRAIL-R-induced apoptotic mechanism. 相似文献
4.
The chirality of the title heterocycles is discussed considering their genesis by desymmetrization of the corresponding adamantanes. Some rules for the specification of the absolute configurations of the enantiomers (R or S) for this type of compounds are proposed. © 1996 Wiley-Liss, Inc. 相似文献
5.
We have reviewed the experimental results which indicate that endogenous type I interferon (IFN) present either constitutively or possibly induced by the tumor plays an important role in limiting the development of transplantable tumors in mice. Thus, treatment with potent polyclonal neutralizing antibodies to IFN alpha/beta markedly enhanced the subcutaneous growth, invasiveness and metastases of xenogeneic tumor cells (uninfected or infected with RNA or DNA viruses) in athymic nude mice; enhanced the intraperitoneal transplantability of six different syngeneic murine tumors in three strains of immunocompetent mice; and completely abrogated the resistance of allogeneic C57Bl/6 (H-2(b)) or C3H (H-2(k)) mice to the multiplication of Friend erythroleukemia cells (H-2(d)) in the liver and spleen resulting in the death of most mice. The mechanisms by which mice respond to the injection of relatively few tumor cells appear to be multiple, to depend on the site of tumor growth, to occur early and prior to an immunologic response. Endogenous type I IFN appears to constitute an essential component of these defense mechanisms enabling the host to restrict tumor growth. 相似文献
6.
Halberg F Cornélissen G Stoynev A Ikonomov O Katinas G Sampson M Wang Z Wan C Singh RB Otsuka K Sothern RB Sothern SB Sothern MI Syutkina EV Masalov A Perfetto F Tarquini R Maggioni C Kumagai Y Siegelova J Fiser B Homolka P Dusek J Uezono K Watanabe Y Wu J Prikryl P Blank M Blank O Sonkowsky R Schwartzkopff O Hellbrügge T Spector NH Baciu I Hriscu M Bakken E 《Neuro endocrinology letters》2003,24(6):479-498
7.
离子注入技术是将某种元素的原子进行电离,并使其在电场中加速,在获得较高的速度后射入固体材料表面。在离子注入过程中,被电离的离子在电场作用下加速运动,离子靠着本身获得的动能进入基体表面,在表层中运动的离子与基体原子作用损失能量后在一定的位置停留下来。该技术自60年代问世以来,主要用于材料改性等方面。80年代中期,我国学者开始将其用于农作物育种方面的研究,大大拓宽了离子注入技术的应用领域。所用实验材料的基因及表现型见Tab3,我们将氢离子(E=35MeV)注入处于胚胎发育后期的家蚕卵内(Tab1),观察其对家蚕形态及遗传方面的影响,结果表明:(1)在家蚕胚胎发育的已4期注入氢离子,其半致死剂量LD50为1x1010~1x1011cm2这一区间之内;当剂量达到1x1012cm2时,已全部致死(Fig.1&Tab.2);(2)注入氢离子能够使家蚕在第1腹节上产生褐斑(Fig.2)的频率增高。并首次观察到因注入氢离子而导致家蚕出现非成对的褐斑(Fig.3&Tab.4)。(3)在氢离子注入剂量为1x1010cm2时,能够诱变产生大量的嵌合体家蚕,并且诱变频率高达38.5%(Fig.4&Tab.5),这样高的 相似文献
8.
Lithium Polyacrylate (LiPAA) as an Advanced Binder and a Passivating Agent for High‐Voltage Li‐Ion Batteries 下载免费PDF全文
Nicholas P. W. Pieczonka Valentina Borgel Baruch Ziv Nicole Leifer Vadim Dargel Doron Aurbach Jung‐Hyun Kim Zhongyi Liu Xiaosong Huang Sergey A. Krachkovskiy Gillian R. Goward Ion Halalay Bob R. Powell Arumugam Manthiram 《Liver Transplantation》2015,5(23)
Intensive studies of an advanced energy material are reported and lithium polyacrylate (LiPAA) is proven to be a surprisingly unique, multifunctional binder for high‐voltage Li‐ion batteries. The absence of effective passivation at the interface of high‐voltage cathodes in Li‐ion batteries may negatively affect their electrochemical performance, due to detrimental phenomena such as electrolyte solution oxidation and dissolution of transition metal cations. A strategy is introduced to build a stable cathode–electrolyte solution interphase for LiNi0.5Mn1.5O4 (LNMO) spinel high‐voltage cathodes during the electrode fabrication process by simply using LiPAA as the cathode binder. LiPAA is a superb binder due to unique adhesion, cohesion, and wetting properties. It forms a uniform thin passivating film on LNMO and conducting carbon particles in composite cathodes and also compensates Li‐ion loss in full Li‐ion batteries by acting as an extra Li source. It is shown that these positive roles of LiPAA lead to a significant improvement in the electrochemical performance (e.g., cycle life, cell impedance, and rate capability) of LNMO/graphite battery prototypes, compared with that obtained using traditional polyvinylidene fluoride (PVdF) binder for LNMO cathodes. In addition, replacing PVdF with LiPAA binder for LNMO cathodes offers better adhesion, lower cost, and clear environmental advantages. 相似文献
9.
Thermally-induced fluctuations of individual phospholipids in a bilayer lipid membrane (BLM) are converted into collective motions due to the intermolecular interactions. Here, we demonstrate that transbilayer stochastic pores can be generated via collective thermal movements (CTM). Using the elastic theory of continuous media applied to smectic-A liquid crystals, we estimate the pore radius and the energetic requirements for pore appearance. Three types of thermally-induced transbilayer pores could be formed through BLMs: open and stable, open and unstable, and closed. In most of the situations, two open and stable pores with different radii could be generated. Notably, the two pores have the same generation probability. Unstable pores are possible to appear across thin bilayers that contain phospholipids with a large polar headgroup. Closed pores are present throughout the cases that we have inspected. The effects of hydrophobic thickness, polar headgroup size of phospholipids, temperature, surface tension, and elastic compression on the pore formation and pore stability have been examined as well. 相似文献
10.
Walter H. Watson Zhenyuan Song Irina A. Kirpich Ion V. Deaciuc Theresa Chen Craig J. McClain 《生物化学与生物物理学报:疾病的分子基础》2011,1812(5):613-618
Methionine metabolism is disrupted in patients with alcoholic liver disease, resulting in altered hepatic concentrations of S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), and other metabolites. The present study tested the hypothesis that reductive stress mediates the effects of ethanol on liver methionine metabolism. Isolated rat livers were perfused with ethanol or propanol to induce a reductive stress by increasing the NADH/NAD+ ratio, and the concentrations of SAM and SAH in the liver tissue were determined by high-performance liquid chromatography. The increase in the NADH/NAD+ ratio induced by ethanol or propanol was associated with a marked decrease in SAM and an increase in SAH liver content. 4-Methylpyrazole, an inhibitor the NAD+-dependent enzyme alcohol dehydrogenase, blocked the increase in the NADH/NAD+ ratio and prevented the alterations in SAM and SAH. Similarly, co-infusion of pyruvate, which is metabolized by the NADH-dependent enzyme lactate dehydrogenase, restored the NADH/NAD+ ratio and normalized SAM and SAH levels. The data establish an initial link between the effects of ethanol on the NADH/NAD+ redox couple and the effects of ethanol on methionine metabolism in the liver. 相似文献