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1.
Ureteroenterocutaneous stoma is a surgical procedure for urinary diversion by which an intestinal segment is used as a conduit or reservoir for the urine. The intestinal mucosa continues to produce a mucous gel containing desquamated epithelial cells. This mucous gel is easily obtainable from the urine. Glycosphingolipids were isolated from such gels and analyzed with immunological methods using a thin-layer chromatography overlay assay and mass spectrometry. The glycosphingolipids obtained mainly belong to the lacto-type I series comprising ABH, Lea, and Leb determinants. These observations support the intestinal origin of the glycosphingolipids. A regional distribution of the ABH and Lewis antigens, which is in accordance with previous immunohistochemical findings, was observed. 相似文献
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In a chalk grassland in north-western France, vegetation and seed rain were studied along two transects. We compared the efficiency of three types of seed traps (funnel traps, sticky traps, pots exposed in the field) to estimate the annual seed rain and to reveal various processes involved in plant community regeneration. Data were analysed to compare seed density, species richness and composition across seed traps and vegetation. Geostatistical analyses (semivariograms. were used to detect possible autocorrelation and to examine patterns of spatial variation in seed rain and vegetation. The results show that (1) funnel traps are most efficient (56 species, 8079 seeds.m–2). (2) Each type of seed traps brings different information about the processes involved in seed dispersal and seedling establishment. Sticky traps help to understand import and export of seeds in a community through anemochory. Funnel traps may provide a measure of the auto-regeneration capacity of the vegetation through its local seed production. Pot traps integrate various processes involved between seed dispersal and seedling emergence. (3.) The exposition to environmental conditions generates marked spatial patterns in species richness measured in pots and in vegetation, selecting species able to survive. Pot traps indicate that numerous species producing seeds in standing vegetation are unable to establish in the field through seedling recruitment. Our study emphasizes the need of using different types of seed traps and spatial sampling configurations to assess the regenerative potential of standing vegetation and the various mechanisms involved in seed dispersal. A standardised protocol for seed rain sampling was finally developed. 相似文献
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甘蔗三种砍种方式的抗旱性比较研究 总被引:4,自引:0,他引:4
以桂糖 1 1号和新台糖 1 6号作试验材料 ,分剥叶砍种、剥叶不砍种、不剥叶不砍种 3种砍种处理。试验结果表明 :在干旱条件下 ,桂糖 1 1号剥叶不砍种处理的出苗率高 ,死苗率低 ,不剥叶不砍种处理株高和绿叶数数值最大。在生理生化方面 ,干旱区桂糖 1 1号各处理萌芽期间 ,种茎中氨基酸含量 1 4 .2 5~ 1 8.0 0 mg/g Fw,还原糖含量 1 .0 6~ 2 .5 8mg/ g Fw,新台糖 1 6号在干旱区各处理则相反 ,种茎中氨基酸含量 1 .5 0~ 2 .6 3mg/ g Fw,还原糖含量达 1 8.75~ 2 9.5 3mg/ g Fw,种茎近于中度肋迫 ;而桂糖 1 1号在干旱区剥叶不砍种、不剥叶不砍种处理的自然饱和亏缺值与非干旱区各处理基本相同 ,而新台糖 1 6号的则比对照大大提高。因此 ,丘陵坡地应选用桂糖 1 1号剥叶不砍种技术 相似文献
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M. V. Moldaver E. B. Dashinimaev K. S. Vishnyakova P. M. Chumakov Y. E. Yegorov 《Biochemistry (Moscow) Supplemental Series A: Membrane and Cell Biology》2007,1(4):284-293
Three primary cell cultures were derived from a single donor: skin fibroblasts (SF), dermal papilla cells (DP), and mesenchimal stromal cells from lipoaspirate (LA). After a high efficiency introduction of the gene of human telomerase catalytic component (hTERT) in lentiviral construct, we obtained three different strains of immortalized cells. All cells were cultured in a low oxygen (3%) environment. When telomerized cells were grown in atmospheric conditions (21% oxygen), growth retardation was observed after a period of 18–40 days. SF-hTERT and DP-hTERT overcame this retardation. In 30–45 days the rate of their growth became as high as it was in 3% oxygen. LA-hTERT cells were incapable to restore the previous growth rate and after several passages ceased proliferation. We found that telomerized cells were heterogeneous in their ability to form colonies at low density (3 cells per 1 cm2): they made 0–9 population doublings in 7 days. At the same time, mean growth rate of SF-hTERT did not change, while the growth of DP-hTERT and LA-hTERT cells was considerably accelerated in comparison with their growth in mass culture. Transfer of telomerized cells to 21% oxygen reduced their ability to form colonies to a different extent. The total number of cells grown in 21% oxygen was 3 times less than the number grown in 3% oxygen for SF-hTERT and DP-hTERT, and 6 times less for LA-hTERT. Original cells (with the exception of LA) were more sensitive to oxygen level than the corresponding telomerized cells. The total number of cells of all three strains (SF, DP, LA) grown in 21% oxygen was 6–7 times less. We discuss the reasons of incapability of LA-hTERT cells to adapt to atmospheric oxygen. 相似文献
6.
An inhibition reactivation technique was used for histochemical staining of human skeletal muscle sections. Myofibrillar ATPase activity was inhibited by sodium hydroxymercuribenzoate (2.5 mM in 0.1 M Tris-HCl buffer, pH 7.2-7.5, 30 min) and successively reactivated by cysteine which was added to incubation solution (10 mM cysteine-HCl, 2.5 mM ATP-disodium salt, 50 mM potassium chloride and 27 mM calcium chloride in barbital buffer, pH 9.4, 35 min at 37 C). This technique allows the distinction of three fiber categories with different staining intensities in single cross-section. Dark, intermediate and light fibers correspond to IIB, I, and IIA types, respectively. Storage of air dried sections in the freezer at -20 C for one month had no influence on staining characteristics. 相似文献
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ABSTRACT: BACKGROUND: Single incision laparoscopic surgery (SILS) is a newly growing technique to replace a more invasive conventional multiple portal laparoscopic surgery. The objective of this study was to compare single (SILS) with three portal (Conventional) laparoscopic splenectomy in dogs. Mongrel dogs (n = 18), weighting 15 +/- 3 kg, were selected for this study (n = 12 SILS; n = 6 conventional). The area from xiphoid to pubis was prepared under aseptic conditions in dorsal recumbency with the head down and tilted 30 degree in the right lateral position. Pneumoperitoneum was established by CO2 using an automatic high flow pressure until achieving 12 mm Hg. Instrumentation used consisted of curved flexible-tip 5 mm Maryland forceps and ultracision harmonic scalpel for sealing and cutting of the vessels and splenic attachments. RESULTS: All dogs recovered uneventfully. The splenectomy procedure using SILS and conventional methods were significantly different in the respective operative time (29.1 +/- 1.65 vs. 42.0 + 2.69 min) and the length of the surgical scar (51.6 +/- 1.34 mm vs. 72.0 +/- 1.63 mm; P < 0.001). There were no post-operative wound complication including inflammation, infection, hernia formation and dehiscence up to one month after surgery. Meanwhile, the conversion to open surgery or application of additional portals was not required in both approaches. CONCLUSION: This study demonstrated that SILS is a safe and feasible operation and could be used as an alternative approach to three portal (Conventional) for splenectomy in dog. 相似文献
8.
《Endocrine practice》2011,17(2):177-184
ObjectiveTo describe the clinical presentation, localization modalities, and management of patients with tumor-induced osteomalacia (TIO).MethodsWe performed a retrospective analysis of case records of patients diagnosed with TIO between January 1996 and March 2010 at our institution in Mumbai, India.ResultsNine patients (6 female and 3 male) with a mean age of 37.5 ± 17.5 years with biochemical and imaging evidence of TIO were included in the study. Overall, patients presented with proximal muscle weakness and pain. Three patients had neurofibromatosis 1, one had isolated schwannoma, and one had epidermal nevus syndrome. The mean delay in diagnosis was 7.67 years. Biochemical studies revealed normal serum calcium (mean, 9.2 ± 0.8 mg/dL), low serum phosphorus (mean, 1.36 ± 0.54 mg/dL), and low maximal tubular reabsorption of phosphorus factored for glomerular filtration rate (mean, 0.94 ± 0.49 mg/dL). Fibroblast growth factor-23 was increased in 3 of the patients without neurofibromatosis but was normal or near-normal in all the patients with neurofibromas. A fludeoxyglucose F 18 positron emission tomography (FDG PET) scan helped to localize the tumors in 4 of the 5 patients with diagnoses other than neurofibromatosis. Three patients underwent surgical excision and were cured. One patient underwent biopsy and partial excision. Histopathologic findings were suggestive of phosphaturic mesenchymal tumor, benign fibrous histiocytoma, nonossifying fibroma, and sciatic nerve schwannoma.ConclusionThere is a well-known delay in the diagnosis of TIO. FDG PET is a useful modality for localization of tumors. Preoperative localization increases the odds for cure after surgical excision. (Endocr Pract. 2011;17: 177-184) 相似文献
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Comparison of single seed descent and anther culture-derived lines of three single crosses of rice 总被引:2,自引:0,他引:2
B. Courtois 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,85(5):625-631
Summary Distribution parameters (mean, variance, skewness and kurtosis) of 12 quantitative traits were evaluated for inbred lines generated through single seed descent (SSD) and anther culture (AC) of two japonica x japonica hybrids and one japonica x indica hybrid of rice. For most of the traits the data were normally distributed, and the means and variances were found to be identical for SSD- and AC-derived lines of the given hybrids. However, for some other traits, differences between the two population types were observed, mainly in the lines derived from the intra-japonica crosses. A tentative explanation for these differences is given. Nevertheless, our results suggest that SSD and AC are equally effective breeding techniques for producing agronomically useful lines of rice. 相似文献
10.
Comparison of three methods to estimate the center of mass during balance assessment 总被引:5,自引:0,他引:5
Evaluation of postural control is generally based on the interpretation of the center of pressure (COP) and the center of mass (COM) time series. The purpose of this study is to compare three methods to estimate the COM which are based on different biomechanical considerations. These methods are: (1) the kinematic method; (2) the zero-point-to-zero-point double integration technique (GLP) and (3) the COP low-pass filter method (LPF). The COP and COM time series have been determined using an experimental setup with a force plate and a 3D kinematic system on six healthy young adult subjects during four different 30 s standing tasks: (a) quiet standing; (b) one leg standing; (c) voluntary oscillation about the ankles and (d) voluntary oscillation about the ankles and hips. To test the difference between the COM trajectories, the root mean square (RMS) differences between each method (three comparisons) were calculated. The RMS differences between kinematic-LPF and GLP-LPF are significantly larger than kinematic-GLP. Our results show that the GLP method is comparable to the kinematic method. Both agree with the unified theory of balance during upright stance. The GLP method is attractive in the clinical perspective because it requires only a force plate to determine the COP-COM variable, which has been demonstrated to have a high reliability. 相似文献
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浑善达克沙地不同植物功能型光合作用和水分利用特征的比较 总被引:1,自引:2,他引:1
为了比较不同植物功能型在沙地生境下光合作用和水分利用效率的差异,测定了浑善达克沙地3种功能型的代表种的气体交换特征来比较它们的光合碳固定能力和水分利用状况。3个代表种的气体交换日变化结果表明乔木的光合速率和水分利用效率比草本和灌木的低,而蒸腾速率和气孔导度较高,经过中午的光合午休后,乔木的光合速率在下午没有恢复,而草本和灌木都有不同程度的恢复。在所测定的所有代表物种中,研究地全部的乔木(3种)和灌木(6种)以及典型的草本(2 5种) ,气孔导度与光合速率和蒸腾速率都成显著的正相关关系;另外,在同样的叶片水势情况下,乔木植物的气孔导度最低,在同样的蒸腾速率情况下,乔木植物的光合速率最低。这些结果表明乔木在CO2 同化和H2 O蒸腾平衡上具有低的水分利用效率。从这个角度考虑,我们认为在对沙地进行恢复时,一些草本和灌木种比乔木更合适 相似文献
13.
Copper is found incorporated into the crystal structure of cytosine monohydrate grown from aqueous solution of commercially available cytosine. Upon ionizing irradiation, the crystals exhibited the electron paramagnetic resonance (EPR) spectra characteristic of Cu(II) complex. Planar coordination bonding to the cupric ion, having three nitrogen atoms and an oxygen as ligands, is interpreted to bridge two cytosine molecules, replacing the two cytosine-cytosine hydrogen bonds present in pure crystals. The EPR signals are much stronger for crystals grown from the solutions to which small amount of copper powder were added. 相似文献
14.
Three different methods were used to prepare conjugates for the detection of rods of the Bacteroides fragilis group by direct immunofluorescence. Lyophilized conjugates were prepared. Three sets (five in each) of monovalent conjugates against serotype strains of B. fragilis (including conjugate E/E1 + E2) and polyvalent conjugate (A + B + C + D + E1 + E2) were obtained. Each conjugate was prepared in two variants: 1. unabsorbed, 2. absorbed with tissue powder prior to lyophilization. Conjugates obtained by precipitation of sera with 50% ethanol and direct coupling of gammaglobulins with stain were found to meet the requirement for good fluorescence reagents and are well suited for the detection of B. fragilis by direct immunofluorescence. Absorption of the conjugates with tissue powder before lyophilization did not affect their quality. 相似文献
15.
F. R. Adler 《Journal of mathematical biology》1990,28(6):695-713
Armstrong and McGehee (1980) have shown that two species modeled in continuous time can coexist on a single resource provided
that one species oscillates autonomously. This paper demonstrates the parallel result in discrete time. I consider a deterministic
model of two asexual types in a single patch competing for a single resource, and show that such systems generically produce
oscillatory coexistence or bistability if one of the types displays periodic or chaotic behavior in isolation. The conditions
for coexistence or bistability are derived in terms of the convexity of the functions describing fitness as a function of
resource availability. I also analyze whether or not a stable type, a type with a stable equilibrium population size when
considered in isolation, can invade a periodic orbit of an unstable type, and show that the same convexity condition distinguishes
these two cases. The widely considered exponential or Ricker model for population dynamics lies on the boundary between the
two cases and is highly degenerate in this context. 相似文献
16.
Three sludge types from the same treatment stream (undigested liquid, anaerobically digested liquid and dewatered, anaerobically digested cake) were used in a field based tub study. Amendments (4, 8, and 16 Mg dry solid (ds)ha(-1)) were incorporated into the upper 15 cm of a sandy loam soil prior to sowing with rye-grass (Lolium perenne L.). Nitrogen transformations in the soil were determined for the 80 d period following incorporation. Nitrogen uptake and crop yield were measured in the cut sward 35 and 70 d after sowing. The study showed that application of sewage sludge at rates as low as 4 Mgha(-1) can have a nutritional benefit to rye-grass over the two harvests. Differences in N transformation, and hence crop nutritional benefit, between sludge types were evident throughout the experiment. In particular, the dewatering process changed the mineral N characteristics of the anaerobically digested sludge, which, when not dewatered, outperformed the other sludges in terms of yield and mineralisation rate at both harvests. The dewatered sludge produced the lowest yield of rye-grass. The undigested liquid sludge had the lowest foliar N and soil NO(3)-N concentrations, possibly immobilised as the large oxidisable C component of this sludge was metabolised by the microbial biomass. Correlation data support the concept of preferential uptake of NH(4)-N over NO(3)-N in Lolium perenne. Results are discussed in the context of managing sludge type and application for a plant nutrient source and NO(3)-N release. 相似文献
17.
Comparison of denitrification characteristics among three habitat types of a large river floodplain: Atchafalaya River Basin,Louisiana 总被引:1,自引:0,他引:1
Mobile forms of nitrogen leach from upland environments into aquatic systems, often discharging to coastal zones. Addition of nitrogen to once N-limited systems results in a host of changes ranging from eutrophication to loss of biodiversity. Floodplains can ameliorate these changes by removing and sequestering nitrogen. In many coastal floodplains, sedimentation causes lakes to transition to baldcypress swamps, and ultimately to bottomland hardwood (BLHW) forests. These habitats differ in their contact with floodwater, which directly and indirectly affects their ability to process nutrients, but the effects of habitat change on denitrification at the floodplain scale cannot be predicted because of lack of suitable data. This study compared denitrification characteristics among the aforementioned habitats within the Atchafalaya River Basin (ARB). Microcosms were established in the laboratory, and the acetylene block technique was used to estimate four denitrification characteristics: background denitrification rates, maximum rates, time to reach maximum rates, and the linear response of denitrification to nitrate concentration. There were significant differences in denitrification characteristics among the three habitat types; specifically, all habitats differed in the time required for denitrification to respond to nitrate in the overlying water, and denitrification in lake habitats differed from both BLHWs and baldcypress swamps. Landscape-scale models should account for different linear relationships between denitrification and nitrate concentrations, and different response times to nitrate concentrations for different habitats. Because denitrification characteristics differ across habitats within the ARB, continued habitat change within the floodplain will alter nutrient discharge to coastal waters. 相似文献
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Summary Hairy roots of Catharanthus roseus were cultivated in three different types of bioreactors. The best growth and indole alkaloid production was achieved in an airsparged bioreactor with no other mixing. In the stirred bioreactor or in the bioreactor with medium circulation the roots did not grow, suggesting that hairy roots of C. roseus are more sensitive to stress than root cultures of many other plant species. 相似文献
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Sami Akbulut Ilker Arer Alper Kocbiyik Mahmut Can Yağmurdur Hamdi Karakayalı Mehmet Haberal 《International Seminars in Surgical Oncology : ISSO》2009,6(1):4