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91.
Soft-tissue expansion: concepts and complications   总被引:10,自引:0,他引:10  
Soft-tissue expansion complements existing reconstructive techniques and provides new vistas for the plastic surgeon. The technique finds use for overcoming a shortage of tissue, for obtaining skin with special desirable qualities, for creation of flaps otherwise not possible because of the resultant donor site or limited vascularity, for creation of flaps with functioning muscle and overlying soft tissue, and for minimizing flap donor-site problems. Careful planning should include patient counseling, optimum incision placement, and time for a leisurely, complete expansion. The surgery can often be performed under local anesthesia and expansion is tolerated well. Patients should be counseled that the incidence of major complications in an unselected series is 1 in 4 patients. Major complications, however, typically result in a delay in reconstruction and not tissue loss.  相似文献   
92.
Summary. Forty AI bulls were tested for BoLA class I antigens by means of eight specific polyclonal reagents. By means of immobilization and sperm penetration tests these antigens were not detected on sperm cells. Isoimmunization studies with the use of sperm as antigenic stimuli and insemination of frozen spermatozoa diluted in specific reagents did not prove the presence of BoLA class I antigens on bovine spermatozoa. The cytotoxic tests used in this investigation were not reliable.  相似文献   
93.
The number and concentration of haemopoietic stem cells in the femoral bone marrow and spleen of Wistar rats of different ages were investigated. Stem cells were assayed by the spleen colony technique in irradiated rat recipients. The ability of the recipient spleen to harvest transplanted tissue as a macroscopic colony was found to be dependent on the recipient's age. Changes with senescence were observed also in the concentration and the size of the stem cell compartment both in the marrow and spleen. No differences were demonstrated in the seeding of transplanted colony-forming units into the spleen of recipients of 1 and 4 months of age. A rats-mice strain difference in the effect of senescence on the haemopoietic stem cells is discussed.  相似文献   
94.
The in vitro effects of the analgesic drugs, lornoxicam, indomethacin, tenoxicam, diclofenac sodium, ketoprofen and lincomycine, on the activity of purified human serum paraoxonase (hPON1) (EC 3.1.8.1.) were evaluated. hPON1 was purified from human serum with a final specific activity of 3840 U mg?1 and a purity of 25.3 % using simple chromatographic methods, including DEAE-Sephadex anion exchange and Sepharose 4B-L-tyrozine-1-napthylamine hydrophobic interaction chromatography. SDS-polyacrylamide gel electrophoresis indicated a single protein band corresponding to hPON1. The six analgesics dose-dependently decreased in vitro hPON1 activity, with IC50 values for lornoxicam, indomethacin, tenoxicam, diclofenac sodium, ketoprofen and lincomycine of 0.136, 0.195, 0.340, 1.639, 6.23 and 9.638 mM, respectively. Ki constants were 0.009, 0.097, 0.306, 0.805, 13.010 and 11.116 mM, respectively. Analgesics showed different inhibition mechanisms: lornoxicam, diclofenac sodium and lincomycine were uncompetitive, indomethacin and tenoxicam were competitive, ketoprofen was noncompetitive. According to the results, inhibition potency was lornoxicam>indomethacin>tenoxicam> diclofenac sodium>ketoprofen> lincomycine.  相似文献   
95.
Commercial probiotic capsules that contain probiotic bacteria, kefir, koumiss and yogurt contain beneficial microorganisms that affect cholesterol levels and immune response, and are used for treatment of some diseases. We investigated using immunohistochemistry the effects of kefir, koumiss, yogurt and a commercial probiotic formulation on the expression levels of peroxisome proliferator-activated receptor-α (PPARα) and peroxisome proliferator-activated receptor-β/δ (PPAR-β/δ), which are members of the nuclear steroid hormone receptor superfamily in mouse kidney. Mice were assigned to five groups: group 1, commercial probiotic capsules; group 2, kefir; group 3, koumiss; group 4, yogurt; group 5, control. After oral administration for 15 days, body weights were recorded and kidney tissue samples were obtained. Hematoxylin & eosin staining and the streptavidin-biotin peroxidase complex (ABC) method were applied to tissue sections to examine histology and to determine the localization of PPARα and PPAR-β/δ in the kidneys. We found that the weights of the mice in the kefir, koumiss, yogurt and commercial probiotic capsules groups were increased compared to controls. No differences in kidney histology were observed in any of the experimental groups. Kefir, koumiss, yogurt and the commercial probiotic preparation increased PPARα and PPAR-β/δ expressions.  相似文献   
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98.
Deep tissue injury (DTI) is a severe form of pressure ulcer where tissue damage starts in deep tissues underneath intact skin. In the present study, the contributions of deformation, ischemia, and reperfusion to skeletal muscle damage development were examined in a rat model during a 6-h period. Magnetic resonance imaging (MRI) was used to study perfusion (contrast-enhanced MRI) and tissue integrity (T2-weighted MRI). The levels of tissue deformation were estimated using finite element models. Complete ischemia caused a gradual homogeneous increase in T2 (~20% during the 6-h period). The effect of reperfusion on T2 was highly variable, depending on the anatomical location. In experiments involving deformation, inevitably associated with partial ischemia, a variable T2 increase (17-66% during the 6-h period) was observed reflecting the significant variation in deformation (with two-dimensional strain energies of 0.60-1.51 J/mm) and ischemia (50.8-99.8% of the leg) between experiments. These results imply that deformation, ischemia, and reperfusion all contribute to the damage process during prolonged loading, although their importance varies with time. The critical deformation threshold and period of ischemia that cause muscle damage will certainly vary between individuals. These variations are related to intrinsic factors, such as pathological state, which partly explain the individual susceptibility to the development of DTI and highlight the need for regular assessments of individual subjects.  相似文献   
99.
Endemic atyids of southern Europe have been ascribed to Dugastella, and to subterranean Typhlatya and Troglocaris: Dugastella is epigean, and Typhlatya and Troglocaris are subterranean. An extensive collection from all centres of distribution in southern Europe (excepting the Caucasus) was morphologically examined. A taxonomic redefinition of the group, at different levels, is based on recently published and newly generated molecular phylogeny, whereas newly established taxa have also been morphologically defined. The accordance between the phylogenetic tree and the geographical distributions suggested that a re‐evaluation of some traditionally used morphological characters should generate the most parsimonious solution: this enabled a novel taxonomic division. Gallocaris gen. nov. is erected for the French Troglocaris inermis Fage, 1937, which is more closely related to the epigean Dugastella valentina (Ferrer Galdiano, 1924) than to its supposed congeners. Both western Mediterranean Typhlatya species are closely related to their Caribbean congeners. All other European cave shrimps constitute a monophylum, Troglocaris, which is divisible into subgenera (already with available names): the holo‐Dinaric Troglocaris (Troglocaris) Dormitzer, 1853, south‐eastern mero‐Dinaric Troglocaris (Troglocaridella) Babi?, 1922, and Troglocaris (Spelaeocaris) Matja?i?, 1956, and the Caucasian Troglocaris (Xiphocaridinella) Sadovsky, 1930. Four new species are described: Troglocaris (Troglocaris) bosnica sp. nov. , Troglocaris (Spelaeocaris) prasence sp. nov. , Troglocaris (Spelaeocaris) kapelana sp. nov. , and Troglocaris (Spelaeocaris) neglecta sp. nov. The distribution of all established species is shown, and the value of the morphological characters is discussed. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 786–818.  相似文献   
100.
Sendino, C., Zágor?ek, K. & Taylor, P.D. 2012: Asymmetry in an Ordovician conulariid cnidarian. Lethaia, Vol. 45, pp. 423–431. Conulariids are fossils of the presumed polyps of an extinct scyphozoan cnidarian group. Their cone‐shaped skeletons normally show perfect tetraradial symmetry. However, in the Ordovician species Metaconularia anomala ( Barrande 1867 ) from Drabov (Czech Republic), tetraradial symmetry is compromised in three ways: (1) the skeleton often shows torsion; (2) the four sides may vary in width at the same level within one individual; and (3) one side may be deleted to give a triradial skeleton. Almost 2000 specimens were studied in museum collections. About 56% of analysed specimens are twisted in an anticlockwise direction (sinistral) when viewed from the apex towards the aperture, 28% show no torsion, 1% exhibit clockwise torsion (dextral) and the remaining 15% cannot be classified. Maximum measured torsion rate was 1.5°/mm. A significant negative correlation between torsion rate and length suggests that more highly torted individuals may have survived less well. Almost 5% of individuals show loss of one side for at least part of their lengths. Although many individuals have four sides of equal width, in a significant proportion the sides are of unequal width, up to a maximum/minimum side width ratio of 2 (i.e. widest face twice the width of the narrowest). In the absence of a satisfactory taphonomic model to explain the asymmetries, they are regarded as mirroring asymmetries in the living conulariids, with the strong preference for sinistral torsion interpreted as an example of a fixed asymmetry that was genetically controlled and heritable. It is speculated that the signalling protein Nodal as well as Hox‐like genes were involved in controlling the asymmetries described in M. anomala.  相似文献   
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