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991.
Ipsen Kikki Lambrecht Zimmermann Regitze Kjær Nielsen Per Sieverts Birkved Morten 《The International Journal of Life Cycle Assessment》2019,24(7):1239-1253
The International Journal of Life Cycle Assessment - The purpose of the study is to quantify the environmental performance of Smart City Solutions at urban system level and thus evaluate their... 相似文献
992.
Simone Fior Per Ola Karis 《Cladistics : the international journal of the Willi Hennig Society》2007,23(4):362-372
The phylogeny of the genus Moehringia (Caryophyllaceae) is investigated by means of analyzing nuclear (ITS) and chloroplast (matK) sequence data in combination with morphological characters. Parsimony and Bayesian methods yield consistent results, and a common phylogenetic signal is shared by the nuclear and chloroplast data. Morphological characters are affected by a high level of homoplasy, but they provide valuable information when analyzed in combination with the molecular data. Moehringia is paraphyletic to Arenaria with the Iberian taxa belonging to Moehringia sect. Pseudomoehringia McNeill more closely related to Arenaria. This cladistic evidence led us to reinterpret the homology of the key character used in most, if not all, floras, to separate Moehringia from Arenaria, i.e., the seed strophiole. Thorough anatomical studies were carried out to elucidate the ontogeny of the strophiole, which proved different in Moehringia s. str. and the Iberian taxa. Within Moehringia s. str., two sister clades are recognized (i.e., Moehringia sect. Moehringia and M. sect. Latifoliae much as recognized by McNeill, whereas representatives of M. sect. Diversifoliae are assigned to either groups), and biogeographical events related to the Würm glaciation are considered to play a fundamental role in the evolution and present distribution of the genus. The variation of the strophiole is regarded as adaptability to ecological conditions and dispersal agents. We also propose two new combinations and two replacement names: Arenaria glochidisperma (J.M. Mont.) Fior et P.O. Karis, comb. nov., Arenaria tejedensis (Willk.) Fior et P.O. Karis, comb. nov., Arenaria suffruticosa Fior et P.O. Karis, nom. nov. for Moehringia intricata Willk., and Arenaria funiculata Fior et P.O. Karis, nom. nov. for Moehringia fontqueri Pau. © The Willi Hennig Society 2007. 相似文献
993.
In West Africa, policies for prescribed early fire, grazing and selective tree cutting in the savanna-woodlands are rarely based on long-term experimental studies. The purpose of this study was to provide scientific evidence based on field data from two case studies for an informed discussion on the long-term response of herbaceous abundance both at the community and individual species levels to fire, grazing, selective cutting and their interactions. A long-term factorial experiment was established in two State forest reserves in Burkina Faso that mainly differ in their soil attributes. Community abundance data recorded from line intercept sampling over 13 years were analyzed using a multivariate ordination technique known as principal response curves (PRC). 相似文献
994.
Per Strset Oddvar Stokke Egil Jellum 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1978,145(3):351-357
Gas chromatography—mass spectrometry with an on-line data system was used to identify monosaccharides and monosaccharide derivatives in human seminal plasma. The carbohydrates were converted into the methoxime—trimethylsilyl derivatives before separation in open tubular glass capillary columns coated with SE-30. Twenty-one different compounds were detected in the seminal fluid, of which twelve have not been recognized before. Seventeen of the monosaccharides have previously been identified in urine. Similar patterns of sugars were found both in fertile and infertile individuals, including one with azoospermia. The compounds identified are, with the possible exception of
-ribose, present as free monosaccharides at the time of ejaculation, and they do not seem to be preformed by spermatozoa. 相似文献
995.
In 283 dairy cows suffering from internal disorders the serum proteins were studied by agarose gel electrophoresis supplemented by total protein and albumin determinations. The clinical diagnoses could be grouped according to protein pattern. Group 1 (abomasal displacement and traumatic muscle injury) did not appreciably affect the serum protein concentrations and represented primarily non-inflammatory diseases or diseases of non-infectious origin. Group 2 (leukosis) occupied an exceptional position, with heavy lowering of albumin unaccompanied by a corresponding rise of total globulin. The γ-globulin concentration was significantly lowered. Group 3 (acute traumatic peritonitis) represented an acute inflammatory process with increase chiefly of the α-globulins, while the γ-globulin concentration was normal. Group 4 (chronic traumatic peritonitis, summer mastitis, chronic subclinical mastitis, chronic laminitis and polyarthritis, urinary tract infection, abscess, and sub-acute-chronic pneumonia) comprised diseases chiefly of chronic inflammatory character and with infectious origin. Especially characteristic was the heavy rise of globulins in general and of γ-globulin in particular. In most cases there was a large increase also of the α- and p-globulin fractions. 相似文献
996.
997.
Reports on serious artifacts associated with the use of cell fixation in studies of the cellular uptake of cell-penetrating peptides, also denoted protein transduction domains, have demonstrated the need for a reevaluation of the current understanding of peptide-mediated cellular delivery of large, hydrophilic molecules. In a recent study on the internalization in unfixed cells of penetratin and its analogues in which tryptophans are substituted for phenylalanines (Pen2W2F), lysines for arginines (PenArg), and arginines for lysines (PenLys), we revealed large dissimilarities in cell interactions among the peptides [Thorén et al. (2003) Biochem. Biophys. Res. Commun. 307, 100-107]. We here investigated possible correlations with their respective affinities for the lipid membranes of large unilamellar vesicles. The variations found in membrane affinity correlated qualitatively with differences in hydrophobicity among the peptides but were by far too small to account for the striking differences in cell membrane binding. Interestingly, we found that the inclusion of a small fraction of lipids conjugated to poly(ethylene glycol) (PEG) in the vesicles both stabilized the vesicle dispersion against peptide-induced aggregation and, furthermore, enhanced the binding of the peptides to the membrane. By use of PEG-conjugated lipids, it could be shown that vesicle aggregation drives an alpha-helix to beta-sheet conformational transition for these peptides. A similar transition was discovered at submicellar concentrations of sodium dodecyl sulfate in aqueous solution for all peptides except PenLys. Finally, significant changes of the contributions to CD spectra from aromatic residues due to their insertion into the membrane were observed. 相似文献
998.
Woldbaek PR Stromme TA Sande JB Christensen G Tønnessen T Ilebekk A 《American journal of physiology. Heart and circulatory physiology》2003,285(5):H2233-H2239
We have tested a new fiber-optic pressure recording system, Samba, with a thin fiber [outer diameter (OD) = 0.25 mm] and a pressure sensor (length and OD = 0.42 mm) attached to the end. The accuracy of the system tested in vitro was good, with a coefficient of variation of 2.54% at 100 mmHg. The drift was <0.45 mmHg/h, and the temperature sensitivity was approximately 0.07 mmHg/1 degrees C between 22 and 37 degrees C. The frequency response characteristics were similar to a 1.4-Fr Millar catheter (0-200 Hz). Introduction of the Samba sensor from the right carotid artery into the left ventricle in six mice caused no drop in mean aortic pressure, whereas introduction of a 1.4-Fr Millar catheter (OD = 0.47 mm; n = 6) caused a pressure drop from 91.6 +/- 9.2 to 65.1 +/- 6.2 mmHg; P < 0.05. Thus the Samba sensor system may represent a new alternative to assess hemodynamic variables in the murine cardiovascular system. 相似文献
999.
Human immunodeficiency virus type 1 attachment,coreceptor, and fusion inhibitors are active against both direct and trans infection of primary cells 总被引:1,自引:0,他引:1 下载免费PDF全文
Ketas TJ Frank I Klasse PJ Sullivan BM Gardner JP Spenlehauer C Nesin M Olson WC Moore JP Pope M 《Journal of virology》2003,77(4):2762-2767
Inhibitors of human immunodeficiency virus type 1 attachment (CD4-immunoglobulin G subclass 2), CCR5 usage (PRO 140), and fusion (T-20) were tested on diverse primary cell types that represent the major targets both for infection in vivo and for the inhibition of trans infection of target cells by virus bound to dendritic cells. Although minor cell-type-dependent differences in potency were observed, each inhibitor was active on each cell type and trans infection was similarly vulnerable to inhibition at each stage of the fusion cascade. 相似文献
1000.
Changes in cumulus-oocyte complexes of pregnant and non-pregnant camels (Camelus dromedarius) during maturation in vitro 总被引:2,自引:0,他引:2
Torner H Heleil B Alm H Ghoneim IM Srsen V Kanitz W Tuchscherer A Fattouh EM 《Theriogenology》2003,60(5):977-987
The aim of the present study was to examine the cumulus morphology and the oocyte chromatin quality of camel cumulus-oocyte complexes (COCs) at the time of recovery, and to monitor changes in oocyte chromatin configuration and apoptosis in cumulus cells from camel COCs during in vitro maturation (IVM) (0, 12, 24, 32, 36, 42, and 48 p.IVM) depending on pregnancy of donors. A total of 1023 COCs were isolated from sliced ovaries after slaughtering of 47 pregnant and 43 non-pregnant camels in an abattoir. The mean number of COCs per donor was 10.3 in pregnant and 12.5 in non-pregnant donors. The cumulus morphology of COCs was independent of the type of donor and was divided in COCs with compact (26.9 and 28%), dispersed (39.3 and 46%), corona radiata cumulus investment (27.9 and 21.7%) and without cumulus (6 and 4.2%), respectively for pregnant and non-pregnant donors. The highest proportion of COCs exhibited dispersed cumulus (P<0.05). Oocytes with meiotic stages of diplotene >50% were found only in compact (55 and 56.5%) and in dispersed COCs (58.4 and 60%), respectively for pregnant and non-pregnant donors. During IVM (0-48h) the first significant onset of specific meiotic stages were different in oocytes from pregnant donors: metaphase 1 (24-32h), metaphase 2 (36-42h), versus oocytes from non-pregnant donors: metaphase 1 (24h), metaphase 2 (32-48h) (P<0.05). The level of apoptotic cells in cumuli of matured COCs increased during IVM and was higher in matured COCs from non-pregnant donors for each time point during IVM (P<0.01). Camel oocytes meiosis during IVM is accompanied by a drastic increase of apoptosis in the surrounding cumulus cells 0-32 and 0-24h during IVM, respectively for pregnant and non-pregnant donors. The oocytes of pregnant camels require 36h of maturation to reach levels of >50% metaphase 2 stage in comparison to oocytes from non-pregnant donors where 32h are sufficient. The earlier onset of apoptosis in the COCs derived from non-pregnant donors possibly determines the faster progression of the oocytes through the final stages of meiosis. 相似文献