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91.
92.
The binomial test is applied for the problem of testing a hypothesis based on a sample of independent, but non-identically distributed random variables. The used basic idea is that each random variable indicates the presence of the hypothesis. Hence each random variable is transformed such that the binomial test can be used as a simple procedure.  相似文献   
93.
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   
94.
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   
95.
96.
The Tasmanian devil is suffering from a severe population decline due to the fatal Devil Facial Tumour Disease (DFTD). The development of assisted reproductive technologies such as AI and long-term sperm storage could facilitate genetic management of captive insurance populations. The aim of this study was to characterise semen samples collected post-mortem, and to develop a suitable diluent for short-term preservation of devil sperm. Low numbers of sperm (1.33 ± 0.85 × 106 sperm per male) were extracted from the epididymides of 17 males. Devil sperm sample characteristics such as concentration and morphology were similar to other dasyurids. The most commonly observed morphological abnormalities were midpiece separation, tail curling, and tail twisting (on the axial plane). Changes in motility occurred throughout the regions of the epididymis with (mean ± SD) 29.4 ± 16.8, 46.8 ± 13.6 and 29.4 ± 18.1% of sperm exhibiting motility, and 88.9 ± 11.4, 32.0 ± 24.3 and 0.1 ± 0.2% of motile sperm exhibiting forward progressive motility in the cauda, corpus and caput, respectively. Sperm from the cauda and corpus epididymis maintained 31.7 ± 26.6 and 80.6 ± 85.9%, respectively, of initial motility after 12 h at 15 °C in a TEST yolk buffer diluent. These findings provided new information regarding devil sperm biology and short-term sperm storage; such information is necessary for future development of long-term sperm preservation methods in the Tasmanian devil.  相似文献   
97.
Matschie's tree kangaroo (Dendrolagus matschiei) is an endangered species that has been bred in captivity since the 1970s. In 1992, the Tree Kangaroo Species Survival Plan® (TKSSP) was established to coordinate the captive management of Association of Zoos and Aquariums (AZA) D. matschiei. The TKSSP makes annual breeding recommendations primarily based on the mean kinship (MK) strategy. Captive breeding programs often use the MK strategy to preserve genetic diversity in small populations—to avoid the negative consequences of inbreeding and retain their adaptive potential. The ability of a captive breeding program to retain the population's genetic diversity over time can be evaluated by comparing the genetic diversity of the captive population to wild populations. We analyzed DNA extracted from blood and fecal samples from AZA (n = 71), captive (n = 28), and wild (n = 22) D. matschiei using eight microsatellite markers and sequenced the partial mitochondrial DNA control region gene. AZA D. matschiei had a similar expected heterozygosity (He = 0.595±0.184) compared with wild D. matschiei (He = 0.628±0.143), but they had different allelic frequencies (FST = 0.126; P<0.001). AZA D. matschiei haplotype diversity was almost two times lower than wild D. matschiei (). These data will assist management of AZA D. matschiei and serve as a baseline for AZA and wild D. matschiei genetic diversity values that could be used to monitor future changes in their genetic diversity. Zoo Biol 30:636–646, 2011. © 2010 Wiley Periodicals, Inc.  相似文献   
98.
Recorded in several species including humans, geophagia or soil eating has been observed in both wild and domesticated horses and has generally been regarded as an indication of nutritional deficiency or "boredom". Studies of soils consumed by different species have led to several theories as to the identity of soil constituents that stimulate geophagia. In this study, geochemical analysis of 13 equine geophagic sites from different parts of Australia was undertaken. Significantly larger concentrations of iron and copper were found in soil samples from geophagic sites when compared to paired control samples, suggesting that these elements provide the stimulus for geophagia.  相似文献   
99.
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   
100.
Diethylcarbamazine (DEC) was active in vitro against infective larvae and microfilariae of Brugia pahangi but only at high concentrations. When fed to mosquitoes which were infected with B. pahangi it had little or no activity. In jirds it was inactive against B. pahangi microfilariae and adults when administered at 300 mg/kg for 5 days either by the intraperitoneal or oral route. In cats given 25 or 50 mg DEC/kg intraperitoneally on 3 or 5 occasions it was not microfilaricidal, but most of the adult worms died within 30 days of the end of treatment. Although most microfilariae disappeared from the blood of cats immediately (i.e., within an hour) after treatment, they reappeared within a few hours in the same numbers. Microfilarial levels were reduced after treatment but there was no precipitate decline as occurs in human B. malayi patients.  相似文献   
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