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Bone turnover markers (BTMs) are classified as either formation or resorption markers. Their concentrations in blood or urine of adults are considered to reflect the rate of bone remodelling and may be of use in the management of patients with bone disease. Major inter-method differences exist for BTMs, and harmonisation of methods is currently being pursued at an international level. Based on published data, this article describes age- and sex-specific Australian consensus reference intervals for adults for serum procollagen type I amino-terminal propeptide (s-PINP) and serum β-isomerised carboxy-terminal cross-linking telopeptide of type I collagen (s-CTX).  相似文献   
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报道了内蒙古清水河黄土丘陵地区发现的紫萼藓科1新变种——缨齿藓菱形变种[Jaffueliobryum wrightii(Sull.)Thér.var.rhombicumX.L.BaiSarula],该变种与干旱山地岩面生境中的原变种缨齿藓[Jaffueliobryum wrightii(Sull.)Thér.]相似,生境的变化导致其形态发生变化,主要表现在上部细胞菱形和细胞壁背部强烈加厚,未分化的叶上部边缘细胞、中肋横切面细胞不分化,叶片长0.7~0.8mm,毛尖长0.8~1.3mm。文中对缨齿藓及其新变种的形态学特征,分布和生境进行了描述,并提供了显微照片,另外,列出了缨齿藓属5个种的检索表。  相似文献   
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目的研究长爪沙鼠发情周期,揭示发情规律,优化判定方法。方法连续18 d采集50只长爪沙鼠阴道上皮脱落细胞涂片,采用角化细胞计数法研究长爪沙鼠发情周期规律。比较瑞氏染色、HE染色和直接镜检判定发情周期4个时相的优缺点。结果长爪沙鼠的发情周期有稳定型、不稳定型、假孕三种类型。其中稳定型占68.6%,发情周期为(106.3±35.0)h,可分为4个时相。4个时相角化细胞的比例分别为发情前期(13.5±7.8)%、发情期(86.7±9.9)%、发情后期(27.9±12.8)%和发情间期(3.3±2.8)%。结论角化细胞计数能准确地判定长爪沙鼠的发情周期及各个时相。直接镜检法能快速反映阴道脱落细胞的形态。  相似文献   
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人TRAIL基因cDNA的克隆及其在COS—7细胞中的表达   总被引:1,自引:0,他引:1  
TRAIL(TNFrelatedapoptosisinducingligand)是最近克隆的肿瘤坏死因子(TNF)家族的新成员,由于它的蛋白质结构和生物学效应类似于FAS/APO1L,因此,也被称为APO2L。在低浓度下,TRAIL能迅速地诱导多种肿瘤细胞系的?..  相似文献   
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Cytochrome c oxidase (COX) consists of 13 subunits, 3 encoded in the mitochondrial genome and 10 in the nucleus. Little is known of the role of the nuclear-encoded subunits, some of which exhibit tissue-specific isoforms. Subunit VIa is unique in having tissue-specific isoforms in all mammalian species examined. We examined relative evolutionary rates for the COX6A heart (H) and liver (L) isoform genes along the length of the molecule, specifically in relation to the tissue-specific function(s) of the two isoforms. Nonsynonymous (amino acid replacement) substitutions in the COX6AH gene occurred more frequently than in the ubiquitously expressed COX6AL gene. Maximum-parsimony analysis and sequence divergences from reconstructed ancestral sequences revealed that after the ancestral COX6A gene duplicated to yield the genes for the H and L isoforms, the sequences encoding the mitochondrial matrix region of the COX VIa protein experienced an elevated rate of nonsynonymous substitutions relative to synonymous substitutions. This is expected for relaxed selective constraints after gene duplication followed by purifying selection to preserve the replacements with tissue-specific functions.   相似文献   
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This study proposes Fourier Transform Infrared (FTIR) spectroscopy as a more sensitive, rapid, non‐destructive and operator‐independent analytical diagnostic method for bladder cancer recurrence from bladder wash than other routinely used urine cytology and cystoscopy methods. A total of 136 patients were recruited. FTIR spectroscopic experiments were carried out as a blind study, the classification results of which were then compared with those of cytology and cystoscopy. Firstly, 71 samples (n = 37; bladder cancer and n = 34; control) were studied with transmittance FTIR spectroscopy. After achieving successful differentiation of the groups, to develop a more rapid diagnostic tool and check the reproducibility of the results, the work was continued with different samples (n = 65 as n = 44; bladder cancer and n = 21; control), using the reflection mode (ATR) of FTIR spectroscopy by a different operator. The results revealed significant alterations in moleculer content in the cancer group. Based on the spectral differences, using transmittance FTIR spectroscopy coupled with chemometrics, the diseased group was successfully differentiated from the control. When only carcinoma group was taken into consideration a sensitivity value of 100% was achieved. Similar results were also obtained by ATR‐FTIR spectroscopy. This study shows the power of infrared spectroscopy in the diagnosis of bladder cancer.

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