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611.
612.
FP Zuspan 《Canadian Metallurgical Quarterly》1976,126(7):955-964
Urinary amines were measured in 122 drug-addiction pregnancies. The profile of the patient indicates that 86 per cent were black and had a total of 2.98 pregnancies and 1.97 living children. She made 5.4 prenatal visits to our special drug-abuse prenatal clinic. The 208 antepartum 24 hour urine determinations indicated a mean excretion of epinephrine to be 28 +/- 1.6 mug which rises to 60 mug on the first day post partum. These values indicate increased adrenal gland activity and are more than six times greater than seen in normal pregnancy. The antepartum mean 24 hour urine excretion of norepinephrine is 49.7 +/- 2.6 mug which does not change on the first postpartum day. The antepartum norepinephrine values are 50 per cent higher than seen in normal pregnancy. Drug-addiction pregnancy in patients who are well controlled on methadone have markedly increased adrenal gland activity as evidence by increased levels of epinephrine. The sympathetic nervous system activity as evidenced by urinary norepinephrine is only slightly increased. Drug addiction alters the normal homeostatic mechanisms of pregnancy. 相似文献
613.
Yun Hua Michael D. Bentley Barbara J. W. Cole Kathleen D. Murray A. Randall Alford 《木材化学与工艺学杂志》2013,33(4):503-516
Twelve pentacyclic triterpenes were isolated from the outer bark of river birch, Betula nigra. 3β-Acetoxyolean-11-oxo-12-ene-28-oic acid was isolated for the first time from a Betula species. 3β-Caffeatoxyolean-12-ene-28-oic acid has been spectrally characterized for the first time. 3β-Acetoxyolean-12-ene-28-oic acid and 3β-acetoxyolean-11-oxo-12-ene-28-oic acid have been demonstrated to be active as antifeedants for the Colorado potato beetle, Leptinotarsa decemlineata. 相似文献
614.
Fang Xie Jing S. Pang Anthony Centeno Mary P. Ryan D. Jason Riley Neil M. Alford 《Nano Research》2013,6(7):496-510
Potential utilization of proteins for early detection and diagnosis of various diseases has drawn considerable interest in the development of protein-based detection techniques. Metal induced fluorescence enhancement offers the possibility of increasing the sensitivity of protein detection in clinical applications. We report the use of tunable plasmonic silver nanostructures for the fluorescence enhancement of a near-infrared (NIR) dye (Alexa Fluor 790). Extensive fluorescence enhancement of ~2 orders of magnitude is obtained by the nanoscale control of the Ag nanostructure dimensions and interparticle distance. These Ag nanostructures also enhanced fluorescence from a dye with very high quantum yield (7.8 fold for Alexa Fluor 488, quantum efficiency (Qy) = 0.92). A combination of greatly enhanced excitation and an increased radiative decay rate, leading to an associated enhancement of the quantum efficiency leads to the large enhancement. These results show the potential of Ag nanostructures as metal induced fluorescence enhancement (MIFE) substrates for dyes in the NIR “biological window” as well as the visible region. Ag nanostructured arrays fabricated by colloidal lithography thus show great potential for NIR dye-based biosensing applications. 相似文献
615.
RA Bank M Krikken B Beekman R Stoop A Maroudas FP Lafeber JM te Koppele 《Canadian Metallurgical Quarterly》1997,16(5):233-243
Intact triple helical collagen molecules are highly resistant to proteolytic enzymes, whereas degraded (unwound) collagen is easily digested. This fact was exploited to develop a simplified method for the quantification of the amount of degraded collagen in the collagen network of connective tissues. Essentially, the method involves extraction of proteoglycans with 4 M guanidinium chloride, selective digestion of degraded collagen by alpha-chymotrypsin, hydrolysis in 6 M HCl of the released fragments as well as the residual tissue, and then measurement of the amount of hydroxyproline in both pools. Since the digestion of degraded collagen by alpha-chymotrypsin and measurement of hydroxyproline is not restricted to a specific collagen type, this technique can be applied to a wide variety of connective tissues. The method was validated with articular cartilage. Levels of in situ degraded collagen were about four-fold higher in degenerated (fibrillated) cartilage than in its healthy counterpart derived from the same donor. More detailed investigations revealed that the collagen damage in degenerated cartilage is more extensive at the cartilage surface than in the region adjacent to bone. This was not the case in healthy cartilage; identical low values were obtained at the surface and close to the bone. An impaired collagen network has been hypothesized to be the reason for the swelling of cartilage in osteoarthritis (OA). The present paper presents the first experimental evidence to support this hypothesis: more damage to the collagen network (i.e., more degraded collagen molecules within fibrils) is linearly related to more extensive swelling of the OA tissue in hypotonic saline. 相似文献
616.
Mitochondria undergo structural and functional remodeling to meet the cell demand in response to the intracellular and extracellular stimulations, playing an essential role in maintaining normal cellular function. Merging evidence demonstrated that dysregulation of mitochondrial remodeling is a fundamental driving force of complex human diseases, highlighting its crucial pathophysiological roles and therapeutic potential. In this review, we outlined the progress of the molecular basis of mitochondrial structural and functional remodeling and their regulatory network. In particular, we summarized the latest evidence of the fundamental association of impaired mitochondrial remodeling in developing diverse cardiac diseases and the underlying mechanisms. We also explored the therapeutic potential related to mitochondrial remodeling and future research direction. This updated information would improve our knowledge of mitochondrial biology and cardiac diseases’ pathogenesis, which would inspire new potential strategies for treating these diseases by targeting mitochondria remodeling. 相似文献