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排序方式: 共有126条查询结果,搜索用时 250 毫秒
101.
PD Dr. rer. nat. et med. habil. D. Prawitt T. Enklaar B. Zabel 《Medizinische Genetik》2010,22(4):399-404
The Beckwith-Wiedemann syndrome (BWS) is a pediatric overgrowth syndrome with a variable clinical appearance. The phenotype normalizes with age but the diagnosis of BWS is important as syndrome-specific complications may develop, in particular as a result of a 400-fold increased risk of patients developing certain tumor entities, predominantly nephroblastomas (Wilms’ tumors) and hepatoblastomas, within the first years of life. BWS displays a clinical overlap with other syndromes so that an unambiguous molecular diagnostic is required for risk assessment and appropriate therapy. At the molecular level BWS is associated with the chromosomal region 11p15.5, where two clusters with imprinted genes are located. In patients both genetic mutations and in most cases aberrant DNA methylation can be observed, which pathogenically affect the gene dosage of functionally available monoallelically expressed 11p15.5 genes. Currently only a very incomplete genotype-phenotype correlation exists for BWS. Current research projects provide insights in the molecular etiopathogenesis of the syndrome by identifying interacting partners which modify the epigenetic regulation of imprinted 11p15.5-genes. 相似文献
102.
PD Dr. Pio Fioroni 《Zoomorphology》1970,67(3):263-306
The present study of the development of the different organs of the gut, the vitellophags (primary yolk cells) and the other cell-types concerned with the resorption of the yolk gives the first detailed analysis of an Anomuran development.
Verzeichnis der Abkürzungen in den Abbilduugen A 1 1. Antenne - A 2 2. Antenne - Ab Abdomen - Au Auge - B Blastoderm - Bb Blastodermbildung - Bl Blutlakunensystem - Bm Blastomer (Furchungszelle) - Bp Blastoporus - BZ Blutzelle - Ca Cardiamagen - Cf Carapaxfalte - Cp Caudalpapille - DI Drüsenfilter (Magen) - zDk zentraler Dotterkörper - Do Dorsalorgan - pDp primare Dotterpyramide - tDp tertiare Dotterpyramide (Vitellophagenepithel) - DR Rest des intraembryonalen Dottersackes - ieDS intraembryonaler Dottersack - bDv blastodermale Dottervakuole - sDZ sekunddre Dotterzelle - tDZ tertiare Dotterzelle - sE sekunddre Epithelialisierung (der Vitellophagen) - Ec Ectoderm - Ed Enddarm - Eh Eihiille (Chorion) - Ep Entodermplatte - Et Entodermtrichter - Ex Extremitdt (bsw. Extremitätenanlage) - Fsp Furchungsspindel (Teilungsspindel) - H Herz - ID Innendotter - Im Immigration (des Mesentoderms) - In Invagination (des Mesentoderms) - Ke Kern - KL Kopflappen (optischer Lobus) - KM Kaumuskulatur - L Darmlumen - M Mitose - Ma Magen - Md Mitteldarm - dMd dorsaler Mitteldarmdivertikel (dorsaler Mitteldarmblindsack) - Me Mesoderm - McEn Mesentoderm - Mddr Mitteldarmdrüse - Ml Mandibel - Mp 1 1. Maxilliped (1. Kieferfuß) - Mp 2 2. Maxilliped (2. Kieferfuß) - Mp 3 3. Maxilliped (3. Kieferfuß) - Mu Muskulatur - M1 1. Maxille - M2 2. Maxille - N Ganglien des Nervensystems - Ni Niere (Antennendrüse) - Oe Oesophagus - Ol Oberlippe - Pl Plasma - Py Pylorusmagen - Qv Querverbindung zwischen den Kopflappen - pR perivitelliner Raum - Seg Segment - Sf Sternalfurche - Sto Stomodaeum (Anlage des Vorderdarmes) - TA Thoracoabdominalanlage - Te Telson - Ul Urdarmlumen - V Vitellophage (primare Dotterzelle) - V 1 Vitellophage 1 (1. Vitellophagengeneration) - V 2 Vitellophage 2 (2. Vitellophagengeneration) - dV degenerierende Vitellophage - V intravitelline Vitellophage - IV Initialvitellophage (Lumenbildung) - pV perivitelline Vitellophage - Va Vakuole - Vi gelöster Dotter (im Darmlumen) - fZ freie Zellen (im perivitellinen Raum) Ausgeführt mit Mitteln des Schweizerischen Nationalfonds zur Förderung der wissenschaftlichen Forschung and der Freiwillig Akademischen Gesellschaft der Stadt Basel. 相似文献
Verzeichnis der Abkürzungen in den Abbilduugen A 1 1. Antenne - A 2 2. Antenne - Ab Abdomen - Au Auge - B Blastoderm - Bb Blastodermbildung - Bl Blutlakunensystem - Bm Blastomer (Furchungszelle) - Bp Blastoporus - BZ Blutzelle - Ca Cardiamagen - Cf Carapaxfalte - Cp Caudalpapille - DI Drüsenfilter (Magen) - zDk zentraler Dotterkörper - Do Dorsalorgan - pDp primare Dotterpyramide - tDp tertiare Dotterpyramide (Vitellophagenepithel) - DR Rest des intraembryonalen Dottersackes - ieDS intraembryonaler Dottersack - bDv blastodermale Dottervakuole - sDZ sekunddre Dotterzelle - tDZ tertiare Dotterzelle - sE sekunddre Epithelialisierung (der Vitellophagen) - Ec Ectoderm - Ed Enddarm - Eh Eihiille (Chorion) - Ep Entodermplatte - Et Entodermtrichter - Ex Extremitdt (bsw. Extremitätenanlage) - Fsp Furchungsspindel (Teilungsspindel) - H Herz - ID Innendotter - Im Immigration (des Mesentoderms) - In Invagination (des Mesentoderms) - Ke Kern - KL Kopflappen (optischer Lobus) - KM Kaumuskulatur - L Darmlumen - M Mitose - Ma Magen - Md Mitteldarm - dMd dorsaler Mitteldarmdivertikel (dorsaler Mitteldarmblindsack) - Me Mesoderm - McEn Mesentoderm - Mddr Mitteldarmdrüse - Ml Mandibel - Mp 1 1. Maxilliped (1. Kieferfuß) - Mp 2 2. Maxilliped (2. Kieferfuß) - Mp 3 3. Maxilliped (3. Kieferfuß) - Mu Muskulatur - M1 1. Maxille - M2 2. Maxille - N Ganglien des Nervensystems - Ni Niere (Antennendrüse) - Oe Oesophagus - Ol Oberlippe - Pl Plasma - Py Pylorusmagen - Qv Querverbindung zwischen den Kopflappen - pR perivitelliner Raum - Seg Segment - Sf Sternalfurche - Sto Stomodaeum (Anlage des Vorderdarmes) - TA Thoracoabdominalanlage - Te Telson - Ul Urdarmlumen - V Vitellophage (primare Dotterzelle) - V 1 Vitellophage 1 (1. Vitellophagengeneration) - V 2 Vitellophage 2 (2. Vitellophagengeneration) - dV degenerierende Vitellophage - V intravitelline Vitellophage - IV Initialvitellophage (Lumenbildung) - pV perivitelline Vitellophage - Va Vakuole - Vi gelöster Dotter (im Darmlumen) - fZ freie Zellen (im perivitellinen Raum) Ausgeführt mit Mitteln des Schweizerischen Nationalfonds zur Förderung der wissenschaftlichen Forschung and der Freiwillig Akademischen Gesellschaft der Stadt Basel. 相似文献
103.
PD Dr. Hartmut Greven 《Cell and tissue research》1980,212(1):147-162
Summary The uterine epithelium of pregnant females of the terrestrial ovoviviparous Salamandra salamandra is characterized by a considerable enlargement of its basolateral surface. Chloride and cations (among others sodium), preferentially within the intercellular spaces, can be demonstrated ultrahistochemically. There is indirect evidence of Na+-K+-ATPase activity along the basolateral plasma membranes of the epithelial cells using the Sr-technique for demonstration of a K+-NPPase and 3H-ouabain autoradiography. Preliminary measurements reveal a potential difference across the uterine wall of 15–25mV, the lumenal (mucosal) surface being negative with respect to the coelomic (serosal) surface, and a short circuit current of 200–300 A. The possibly electrogenic ion transport is ouabain-sensitive. The results are in agreement with the model of a forward transporting, i.e. absorptive epithelium. An active transport of solute out of the uterine lumen across the epithelium to the subjacent connective tissue and the blood vessels may be involved in the regulation of an intrauterine milieu appropriate for the development of the offspring.I am indebted to Miss Dr. U. Beigel, Zoologisches Institut der Universität Münster, for linguistic help 相似文献
104.
Prof. Dr. Gerd Flajs Dipl.-Geol. Manfred Vigener Prof. Dr. Helmut Keupp Prof. Dr. Dieter Meischner Dipl.-Geol. Fritz Neuweiler PD Dr. Josef Paul Prof. Dr. Joachim Reitner Dr. Klaus Warnke PD Dr. Helmut Weller Dipl.-Geol. Patrick Dingle Dipl.-Geol. Christian Hensen Prof. Dr. Priska Schäfer Dr. Pascale Gautret Prof. Dr. Reinhold R. Leinfelder PD Dr. Hansmartin Hüssner Dipl.-Geol. Bernd Kaufmann 《Facies》1995,32(1):1-69
Summary This research report contains nine case studies (part II to X) dealing with Palaeozoic and Mesozoic mud mounds, microbial
reefs, and modern zones of active micrite production, and two parts (I and XI) summarizing the major questions and results.
The formation of different types ofin situ formed micrites (automicrites) in close association with siliceous sponges is documented in Devonian, Carboniferous, Triassic,
Jurassic and Cretaceous mounds and suggests a common origin with a modern facies found within reef caves. Processes involved
in the formation of autochthonous micrites comprise: (i) calcifying mucus enriched in Asp and Glu, this type presumably is
linked to the formation of stromatolites, thrombolites and massive fabrics; (ii) protein-rich substances within confined spaces
(e.g. microcavities) result in peloidal pockets, peloidal coatings and peloidal stromatolites, and (iii) decay of sponge soft
tissues, presumably enriched with symbiotic bacteria, lead to the micropeloidal preservation of parts of former sponge bodies.
As a consequence, there is strong evidence that the primary production of micrite in place represents the initial cause for
buildup development. The mode of precipitation corresponds to biologically-induced, matrix-mediated mineralization which results
in high-Mg-calcites, isotopically balanced with inorganic cements or equilibrium skeletal carbonates, respectively. If distinct
automicritic fabrics are absent, the source or origin of micrite remains questionable. However, the co-occurring identifiable
components are inadequate, by quantity and physiology, to explain the enhanced accumulation of fine-grained calcium carbonate.
The stromatolite reefs from the Permian Zechstein Basin are regarded as reminiscent of ancestral (Precambrian) reef facies,
considered the precursor of automicrite/sponge buildups. Automicrite/sponge buildups represent the basic Phanerozoic reef
type. Analogous facies are still present within modern cryptic reef habitats, where the biocalcifying carbonate factory is
restricted in space. 相似文献
105.
Evolutionary relationships among the male and female mitochondrial DNA lineages in the Mytilus edulis species complex 总被引:1,自引:0,他引:1
A novel form of mitochondrial DNA (mtDNA) inheritance has previously been
documented for the blue mussel (Mytilus edulis). Female mussels inherit
their mtDNA solely from their mother while males inherit mtDNA from both
their mother and their father. In males, the paternal mtDNA is
preferentially amplified so that the male gonad is highly enriched for the
paternal mtDNA that is then transmitted from fathers to sons. We
demonstrate that this mode of mtDNA inheritance also operates in the
closely related species M. galloprovincialis and M. trossulus. The
evolutionary relationship between the male and female mtDNA lineages is
estimated by phylogenetic analysis of 455 nucleotides from the large
subunit ribosomal RNA gene. We have found that the male and female lineages
are highly divergent; the divergence of these lineages began prior to the
speciation of the three species of blue mussels. Further, the separation
between the male and female lineages is estimated to have occurred between
5.3 and 5.7 MYA.
相似文献
106.
107.
108.
This paper demonstrates the application of a design tool called BioTRIZ. Its developers claim that it can be used to access biological strategies for solving engineering problems. Our aim is to design a roof for hot climates that gets free cooling through radiant coupling with the sky. The insulation in a standard roof stops the sun and convection from warming the thermal mass. But it also restricts the mass's longwave view of the cool sky. Different solutions to this conflict are offered by BioTRIZ. The chosen solution is to replace the standard insulation component with an open cell honeycomb. The vertical cells would allow longwave radiation to pass, while arresting convection. The solutions offered by BioTRIZ's technological counterpart include no such changes in structure. It is estimated that the thermal mass in the biomimetic roof would remain on average 4.5℃ cooler than in a standard roof over a year in Riyadh, Saudi Arabia. 相似文献
109.
M Gaertner L Müller J F Roos G Cani A R Santos R Niero J B Calixto R A Yunes F Delle Monache V Cechinel-Filho 《Phytomedicine》1999,6(1):41-44
The present study was conducted in order to isolate and identify the phytochemical constituents responsible for analgesic effects shown by a methanolic extract obtained from Sebastiania schottiana roots. Conventional chromatographic procedures led to the isolation of moretenone, glutinol, beta-sitosterol and stigmasterol. The structural elucidation of these compounds was done on the basis of spectral data (IR, 1H- and 13C-NMR) and comparison with authentic samples. Either glutinol or moretenone exhibited marked analgesic action against acetic acid induced abdominal constrictions in mice by intraperitoneal route, indicating 16 to 26-fold higher efficacy than aspirin and paracetamol. When analyzed in a formal-in test, both compounds and standard drugs inhibited only the second phase (inflammatory pain). Our results suggest that the roots of S. schottiana contain analgesic compounds which justify, at least partially, the popular use of this plant for the treatment of urinary problems. 相似文献
110.
Gut Microbes and Health: A Focus on the Mechanisms Linking Microbes,Obesity, and Related Disorders 下载免费PDF全文
The past decade has been characterized by tremendous progress in the field of the gut microbiota and its impact on host metabolism. Although numerous studies show a strong relationship between the composition of gut microbiota and specific metabolic disorders associated with obesity, the key mechanisms are still being studied. The present review focuses on specific complex pathways as well as key interactions. For instance, the nervous routes are explored by examining the enteric nervous system, the vagus nerve, and the brain, as well as the endocrine routes (i.e., glucagon‐like peptide‐1, peptide YY, endocannabinoids) by which gut microbes communicate with the host. Moreover, the key metabolites involved in such specific interactions (e.g., short chain fatty acids, bile acids, neurotransmitters) as well as their targets (i.e., receptors, cell types, and organs) are briefly discussed. Finally, the review highlights the role of metabolic endotoxemia in the onset of metabolic disorders and the implications for alterations in gut microbiota‐host interactions and ultimately the onset of diseases. 相似文献