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111.
Gunji H Hosaka K Huffman MA Kawanaka K Matsumoto-Oda A Hamada Y Nishida T 《Primates; journal of primatology》2003,44(2):145-149
We examined bone mineral density (BMD) of the femoral neck and lumbar vertebrae of four chimpanzee skeletons from Mahale Mountains
National Park, Tanzania, and four captive ones, with a dual energy X-ray absorptiometer. The BMD of Wansombo, an old female
chimpanzee from Mahale , was remarkably lower than the mean of the other six younger adult female chimpanzees and categorized
as osteoporosis. Posture, locomotion, and trunk-sacral anatomy of chimpanzees may have prevented fractures in Wansombo, whose
BMD was below human osteoporosis criteria.
Electronic Publication 相似文献
112.
113.
The purpose of this research was to improve the stability of carbamazepine (CBZ) bulk powder under high humidity by surface
modification. The surface-modified anhydrates of CBZ were obtained in a specially designed surface modification apparatus
at 60°C via the adsorption of n-butanol, and powder x-ray diffraction, Fourier-Transformed Infrared spectra, and differential
scanning calorimetry were used to determine the crystalline characteristics of the samples. The hydration process of intact
and surface-modified CBZ anhydrate at 97% relative humidity (RH) and 40±1°C was automatically monitored by using isothermal
microcalorimetry (IMC). The dissolution test for surface-modified samples (20 mg) was performed in 900 mL of distilled water
at 37±0.5°C with stirring by a paddle at 100 rpm as in the Japanese Pharmacopoeia XIII. The heat flow profiles of hydration
of intact and surface-modified CBZ anhydrates at 97% RH by using IMC profiles showed a maximum peak at around 10 hours and
45 hours after 0 and 10 hours of induction, respectively. The result indicated that hydration of CBZ anhydrate was completely
inhibited at the initial stage by surface modification of n-butanol and thereafter transformed into dihydrate. The hydration
of surface-modified samples followed a 2-dimensional phase boundary process with an induction period (IP). The IP of intact and surface-modified samples decreased with increase of the reaction temperature, and the hydration rate
constant (k) increased with increase of the temperature. The crystal growth rate constants of nuclei of the intact sample were significantly
larger than the surface-modified samples at each temperature. The activation energy (E) of nuclei formation and crystal growth process for hydration of surface-modified CBZ anhydrate were evaluated to be 20.1
and 32.5 kJ/mol, respectively, from Arrhenius plots, but the Es of intact anhydrate were 56.3 and 26.8 kJ/mol, respectively. The dissolution profiles showed that the surface-modified sample
dissolved faster than the intact sample at the initial stage. The dissolution kinetics were analyzed based on the Hixon-Crowell
equation, and the dissolution rate constants for intact and surface-modified anhydrates were found to be 0.0102±0.008 mg1/3 min−1 and 0.1442±0.0482 mg1/3·min−1. The surface-modified anhydrate powders were more stable than the nonmodified samples under high humidity and showed resistance
against moisture. However, surface modification induced rapid dissolution in water compared to the control. 相似文献
114.
Halberg F Cornélissen G Stoynev A Ikonomov O Katinas G Sampson M Wang Z Wan C Singh RB Otsuka K Sothern RB Sothern SB Sothern MI Syutkina EV Masalov A Perfetto F Tarquini R Maggioni C Kumagai Y Siegelova J Fiser B Homolka P Dusek J Uezono K Watanabe Y Wu J Prikryl P Blank M Blank O Sonkowsky R Schwartzkopff O Hellbrügge T Spector NH Baciu I Hriscu M Bakken E 《Neuro endocrinology letters》2003,24(6):479-498
115.
Ogura T Morita K Takeuchi M Otsuka F Iwasaki T Oe K Matsuura K Tobe K Mimura Y Kishida M Makino H Hirakawa M 《Hormone research》2003,59(1):30-34
AIM: The roles of adrenomedullin (AM) in body fluid balance under general anesthesia were investigated. METHODS: Time course changes in plasma osmolality, AM, arginine vasopressin (AVP), and urinary aquaporin 2 (AQP2) in 17 patients undergoing abdominal surgery under general anesthesia were examined. RESULTS: Increases in plasma AM levels were observed in parallel with increases in the levels of urinary AQP2/creatinine (Cr) before induction and 90 and 180 min after initiation of anesthesia. Significant correlations between plasma AM and urinary AQP2/Cr (r = 0.62, p < 0.0001) as well as urinary AVP/Cr and AQP2/Cr (r = 0.60, p < 0.0001) were uncovered. Multivariate stepwise analysis identified plasma AM as the critical independent factor affecting urinary AQP2/Cr level. CONCLUSION: A novel correlation of AM and AQP2 which overlays an AVP-AQP2 system may play a key role in fluid homeostasis during general anesthesia. 相似文献
116.
Activity-dependent mRNA splicing controls ER export and synaptic delivery of NMDA receptors 总被引:12,自引:0,他引:12
Activity-dependent targeting of NMDA receptors (NMDARs) is a key feature of synapse formation and plasticity. Although mechanisms for rapid trafficking of glutamate receptors have been identified, the molecular events underlying chronic accumulation or loss of synaptic NMDARs have remained unclear. Here we demonstrate that activity controls NMDAR synaptic accumulation by regulating forward trafficking at the endoplasmic reticulum (ER). ER export is accelerated by the alternatively spliced C2' domain of the NR1 subunit and slowed by the C2 splice cassette. This mRNA splicing event at the C2/C2' site is activity dependent, with C2' variants predominating upon activity blockade and C2 variants abundant with increased activity. The switch to C2' accelerates NMDAR forward trafficking by enhancing recruitment of nascent NMDARs to ER exit sites via binding of a divaline motif within C2' to COPII coats. These results define a novel pathway underlying activity-dependent targeting of glutamate receptors, providing an unexpected mechanistic link between activity, mRNA splicing, and membrane trafficking during excitatory synapse modification. 相似文献
117.
Hamasaki A Naka H Tamanoi F Umezawa K Otsuka M 《Bioorganic & medicinal chemistry letters》2003,13(9):1523-1526
A novel metal chelator comprising a 4-(naphthalen-1-yl)pyridine and 2-aminoethanethiol was synthesized. This showed inhibitory activity against human protein farnesyltransferase with IC(50) 1.9 microM, induced morphological change in K-ras-NRK cells at 0.5 microg/mL and showed growth inhibition of K-ras-NRK cells with IC(50) 0.32 microg/mL. 相似文献
118.
2',5'-isoDNA mimic chiral peptide nucleic acid (isoPNA) monomers derived from D- and L-aspartic acids were synthesized. These novel monomers were incorporated in aminoethylglycine peptide nucleic acid (aegPNA) thymine dodecamers, and the hybridization properties to RNA and DNA were demonstrated by UV thermal denaturation. 相似文献
119.
120.
The Caenorhabditis elegans nuc-1 gene has previously been implicated in programmed cell death due to the presence of persistent undegraded apoptotic DNA in nuc-1 mutant animals. In this report, we describe the cloning and characterization of nuc-1, which encodes an acidic nuclease with significant sequence similarity to mammalian DNase II. Database searches performed with human DNase II protein sequence revealed a significant similarity with the predicted C. elegans C07B5.5 ORF. Subsequent analysis of crude C. elegans protein extracts revealed that wild-type animals contained a potent endonuclease activity with a cleavage preference similar to DNase II, while nuc-1 mutant worms demonstrated a marked reduction in this nuclease activity. Sequence analysis of C07B5.5 DNA and mRNA also revealed that nuc-1(e1392), but not wild-type animals contained a nonsense mutation within the CO7B5.5 coding region. Furthermore, nuc-1 transgenic lines carrying the wild-type C07B5.5 locus demonstrated a complete complementation of the nuc-1 mutant phenotype. Our results therefore provide compelling evidence that the C07B5.5 gene encodes the NUC-1 apoptotic nuclease and that this nuclease is related in sequence and activity to DNase II. 相似文献