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51.
The brain of Homo floresiensis was assessed by comparing a virtual endocast from the type specimen (LB1) with endocasts from great apes, Homo erectus, Homo sapiens, a human pygmy, a human microcephalic, specimen number Sts 5 (Australopithecus africanus), and specimen number WT 17000 (Paranthropus aethiopicus). Morphometric, allometric, and shape data indicate that LB1 is not a microcephalic or pygmy. LB1's brain/body size ratio scales like that of an australopithecine, but its endocast shape resembles that of Homo erectus. LB1 has derived frontal and temporal lobes and a lunate sulcus in a derived position, which are consistent with capabilities for higher cognitive processing.  相似文献   
52.
53.
Primary lens luxation (PLL) is a well-recognized, painful and potentially blinding inherited ocular condition in dogs. We screened PLL-affected dogs of 30 different breeds, to identify those which carried a previously described c.1473+1 G>A mutation in ADAMTS17 that is associated with PLL in Miniature Bull terriers, Lancashire Heelers, and Jack Russell terriers. This ADAMTS17 mutation was identified in PLL-affected dogs from 14 additional breeds. PLL-affected dogs from some breeds (most notably the Shar pei and the Brittany spaniel) did not carry the G1473+1A ADAMTS17 mutation, indicating they must suffer from a genetically distinct form of the condition. We also estimated the frequency of this ADAMTS17 mutation in some of the breeds. Our findings indicate the mutation segregates in a large number of different breeds of dog, many of which are terriers or breeds with terrier co-ancestry, but some of which have more diverse origins. Our results also indicate that the mutation is present at high frequency within most of the breeds in which it segregates. In the miniature bull terrier breed estimates of mutation frequency ranged from 0.27 to 0.39, corresponding to 7.3-15.2% PLL-affected dogs in this breed. We also identified an increased risk of PLL associated with heterozygosity at ADAMTS17, suggesting that carriers carry a low risk of developing PLL.  相似文献   
54.
The in vitro inhibitory activity of the rice Bowman-Birk inhibitor (rBBI) or soybean Bowman-Birk inhibitor (sBBI) against trypsin-catalyzed activation of pro-matrix metalloproteinase 1 or 9 (pro-MMP-1 or pro-MMP-9), respectively, was investigated using electrophoresis with silver staining, heparin-enhanced zymography, biotinylated gelatin, Biotrak assay, and fluorescence quenched substrate hydrolysis. rBBI at concentrations of 0.08-0.352 mg/mL dose-dependently inhibited the in vitro activation of 45 microg/mL pro-MMP-1 by trypsin. Heparin-enhanced zymography analysis of pro-MMP-1, trypsin-activated MMP-1, and a mixture of pro-MMP-1-trypsin-rBBI showed clear zones associated with trypsin-activated MMP-1 and the absence of clear zones in lanes containing pro-MMP-1 or a mixture of pro-MMP-1, trypsin, and rBBI. The results of the Biotrak assay also indicated that rBBI dose-dependently suppressed the activation of pro-MMP-1 by trypsin. sBBI dose-dependently inhibited the activation of 100 microg/mL of pro-MMP-9 by trypsin. Biotinylated gelatin assays demonstrated that pro-MMP-9 or pro-MMP-9 in the presence of trypsin and BBI did not hydrolyze gelatin, whereas p-aminophenylmercury acetate (APMA)-activated MMP-9 and trypsin-activated MMP-9 caused significant hydrolysis of gelatin. Quenched fluorescence substrate hydrolysis for total MMP activity showed that pro-MMP-1 or pro-MMP-9 did not hydrolyze the substrate Mca-Pro-Leu-Gly-Leu-Dpa-Ala-Arg-NH2; active MMP-1 or MMP-9 hydrolyzed the substrate, but lower substrate hydrolysis was obtained when pro-MMP-1 or pro-MMP-9 was incubated with trypsin in the presence of increasing concentrations of rBBI. The results are discussed in light of the role of MMP-1 and MMP-9 in the process of angiogenesis and the potential of rBBI or sBBI as a functional food ingredient.  相似文献   
55.
Based on several years of data from two populations of the endangered Apollo butterfly (Parnassius apollo, L. 1758), we study how the amount and spatial location of patches of larval (host-plant) and adult (nectar plant) resources affects the distribution of females and their larval offspring in the following year. In the coastal population (nectar-plant and host-plant patches spatially segregated), females moved frequently between patches to aggregate on larger host-plant patches close to nectar-plant patches. In the archipelago population (where nectar-plants and host-plants co-occur), the abundance of females increased with higher proximity to other host-plant patches and with more nectar-plants on the patch. Next year’s larval abundance correlated with the abundance of females in the previous season in both populations. A model of the population dynamics in the two populations in relation to the spatial configuration of nectar and host-plant patches showed that the spatial configuration of larval and adult resources had population-dynamical consequences. In many organisms, different life-history stages use different resources. Incorporation of information on the location and abundance of adult resources can provide additional insight for the suitability of a particular landscape in harbouring a population.  相似文献   
56.
Azima tetracantha L. (needle bush; bee sting bush; Salvadoraceae) is used as a food and for various herbal medicines in Africa, India, and Madagascar, but there is very little information on the secondary metabolites in this species. High concentrations of N-methoxy-3-indolylmethyl-glucosinolate, a common glucosinolate of Brassica crops such as Brussels sprouts and broccoli, were found in the roots and seeds of A. tetracantha. Lower concentrations were detected in the stems and young leaves. The roots also contained another indole glucosinolate that was provisionally identified, from MS data and comparison with indole glucosinolate standards, as N-hydroxy-3-indolymethyl-glucosinolate. The roots, stems, and leaves contained neoascorbigen (the condensation product of N-methoxy-indole-3-carbinol and ascorbic acid). The seeds of A. tetracantha contained a complex mixture of 26 flavonoids predominantly as glycosides and acyl-glycosides, with traces of aglycones. The core aglycones of these flavonoids were identified as quercetin, isorhamnetin (3'-O-methylquercetin), rhamnetin (7-O-methylquercetin), and rhamnazin (7, 3'-di-O-methylquercetin). No flavonoids or anthocyanins were detected in other tissues, and procyanidins were undetectable. The dimeric piperidine alkaloids azimine, azcarpine, and carpaine were found in all tissues of A. tetracantha.  相似文献   
57.
Nisin variants and fragments were reacted with glutathione, and the products of the reactions were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and liquid chromatography/mass spectrometry (LC-MS). Reactions between glutathione and either [Ala5]nisin or [Ala33]nisin resulted in products with two glutathione molecules conjugated to one nisin variant molecule. Only one glutathione molecule was added to [Ala5,Ala33]nisin. Fragmentation of the nisin molecule resulted in nisin 1-12, nisin 1-20, and nisin 1-32 fragments. Each fragment retained two dehydro residues, which subsequently underwent reaction with glutathione. The data indicated that the dehydroalanine residues of nisin are sites of addition for glutathione. Such addition renders the nisin molecule inactive.  相似文献   
58.
Juvenile hybrid striped bass ( Morone chrysops × M. saxatilis ) were fed one of eight diets to evaluate meat and bone meal as a source of crude protein and essential amino acids. Diets contained either 0, 15, 20, 25, 30, 35, 40 or 45% meat and bone meal substituted for an isonitrogenous amount of soybean meal and fish meal. All diets were fed for 7 wk, followed by a 2-wk digestibility trial. Mean consumption, weight gain, and feed conversion ratio were not significantly affected by addition of meat and bone meal into diets. Intraperitoneal and liver lipid concentrations were not significantly affected by meat and bone meal. Fillet proximate composition was not significantly different among treatments. Apparent crude protein, phosphorus, and amino acid availabilities were significantly lower in fish fed 45% meat and bone meal compared to fish fed 30% and lower concentrations and generally lower in fish fed greater than 30% meat and bone meal. Based on these data, it appears meat and bone meal can be used as the primary source of crude protein and essential amino acids in practical growout diets for hybrid striped bass, comprising as much as 45% of the diet. Nutrient availability values were lower in fish fed greater than 30% meat and bone meal and may restrict usage in some applications.  相似文献   
59.
By using the leaves with attached intercalary meristems from greenhouse grown stock plants, five cultivars of Cryptanthus were cultured on modified MS media with 4.5 μM NAA and IBA and 3 μM BA to induce adventitious shoot formation from callus tissue. Contamination was 17–21% for explants taken from stock plants which were sprayed weekly with Agribrom and 27–75% for those taken from stock plants which were not treated. More than 99% true to type plantlets were obtained from non-chimeric plants. Green and albino plantlets were obtained from chimeric plants. The chimeric C. ‘Coster's Favorite’ DeCoster also produced a few chimeric plantlets with intermarginal pink stripes in addition to the green and albino plantlets. Most of the non-chimeric plants took a shorter time to produce plantlets of transplantable size (8–12 mm) than the chimeric ones. Except for albino plantlets, survival rate of plantlets exceeded 95%. A minimum average of 500 rooted plantlets can be obtained in a year from a single well-callused leaf explant. The protocol in this report should speed up the mass production and introduction of desirable new cultivars and hybrids of non-chimeric Cryptanthus.  相似文献   
60.
OBJECTIVE: To describe and evaluate a technique for radical resection of the lateral body wall for treatment of fibrosarcoma with reconstruction using polypropylene mesh and a caudal superficial epigastric axial pattern flap in cats. STUDY DESIGN: Prospective, clinical study. ANIMALS OR SAMPLE POPULATION: Six client-owned cats with fibrosarcoma. METHODS: Six cats with histologically confirmed fibrosarcoma of the lateral body wall were staged using radiography and/or computer tomography scanning. Preoperative radiotherapy was used in 3 cats. All cats had the lateral abdominal wall resected and reconstructed with polypropylene mesh. A caudal superficial epigastric flap was mobilized and rotated to close the skin deficit. The animals were evaluated after surgery for wound complications, tumor recurrence, and metastasis. Outcome was assessed by patient examination and client consultation. RESULTS: Minor dehiscence of the skin flaps occurred in 2 cats, and 1 other cat was successfully resuscitated from respiratory and cardiac arrest after surgery. All tissue specimens were tumor-free at the surgical margins. Follow-up times ranged from 12 to 21 months, with a mean time of 17.2 months. None of the cats had evidence of local tumor recurrence or metastasis; outcome was judged good to excellent in all cats. CONCLUSIONS AND CLINICAL RELEVANCE: Radical lateral body-wall resection and reconstruction is an effective technique for achieving local tumor control with acceptable patient morbidity. Further studies are needed to assess whether the technique will result in improved tumor-free intervals and survival times.  相似文献   
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