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1.
Observed the sexual behavior of 10 male rhesus monkeys before and after castration and during replacement therapy with testosterone propionate. In 10 tests before castration, all of the Ss ejaculated at least once, and in Weeks 21-25 and 51-55 after castration, 50 and 30%, respectively, ejaculated at least once. In the 35 postcastration tests given over a 55-wk period, 2 males did not ejaculate. 50% of the Ss achieved intromission 1 yr after castration. The percentage of castrated Ss showing intromission and ejaculation and the frequency of these responses were higher than those reported for most nonprimate species but did not differ greatly from those reported for the dog. Within 1 wk testosterone propionate restored whatever aspects of behavior were affected to precastration levels. (22 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
F. C. Magne R. R. Mod G. Sumrell W. E. Parker R. E. Koos 《Journal of the American Oil Chemists' Society》1974,51(3):93-100
A number of N-mono and N,N-disubstituted amides of substituted and unsubstituted C18 fatty acids have been prepared and evaluated as base lubricants and lubricant additives. The neat epithioamides possess extreme
pressure lubricant characteristics and are noncorrosive at normal temperatures. The epithioamides also frequently function
as extreme pressure additives and antiwear agents for paraffinic or diester base oils, sometimes in both capacities for both
base oils. The intensiveness of these properties correlated directly with the degree of thiirane substitution in the compound.
Performance in both these capacities at the same levels of epithioation was dependent upon the N- or N,N-substituent groups
present.
One of 12 papers presented in the symposium “Novel Uses of Agricultural Oils” at the AOCS Spring Meeting, New Orleans, April
1973.
ARS, USDA. 相似文献
3.
H. B. Knight Lee P. Witnauer W. E. Palm R. E. Koos Daniel Swern 《Journal of the American Oil Chemists' Society》1959,36(9):382-388
Summary Thirty-one acyloxy or aryloxy esters prepared from hydroxystearic acids have been evaluated as plasticizers for a vinyl chloride-vinyl
acetate copolymer (95∶5). Many of them were found to be primary plasticizers, having outstanding low-temperature performance
when employed at the 35% level. Formulations with these compounds compared quite favorably in tensile properties with those
containing the di-2-ethylhexyl esters of phthalic, sebacic, azelaic, and adipic acids. Volatility losses were similar to those
of the four di-2-ethylhexyl esters. The loss of plasticizer through migration was equal to or less than that from compositions
containing the esters of sebacic, azelaic, and adipic acids but was greater than that of the phthalate ester.
A mechanistic scheme of plasticizer-polymer interaction has been presented, proposing that the rate of diffusion of plasticizer
through the polymer mass is a controlling factor in both good low-temperature performance and the resulting high migration
losses. Methyl esters, some aromatic esters, and esters containing three or more polar centers have improved permanence but
show a more rapid change in torsional modulus as the temperature is lowered during the determination of the Clash-Berg stiffening
temperature.
Eastern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture. 相似文献
4.
Minten IJ Wilke KD Hendriks LJ van Hest JC Nolte RJ Cornelissen JJ 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(7):911-919
The cowpea chlorotic mottle virus (CCMV) is a versatile building block for the construction of nanoreactors and functional materials. Upon RNA removal, the capsid can be reversibly assembled and disassembed by adjusting the pH. At pH 5.0 the capsid is in the native assembled conformation, while at pH 7.5 it disassembles into 90 capsid protein dimers. This special property enables the encapsulation of various molecules, such as protein and enzymes, but only at low pH. It is possible to stabilize the capsid at pH 7.5 by addition of negatively charged polyelectrolytes or negatively charged particles, but these methods all fill the interior of the capsid, leaving little or no space for other cargo molecules. This pH restriction therefore severely limits the range of enzymes that can be encapsulated, and hampers the investigation of the CCMV capsid as a nanoreactor for the study of enzymes in confined spaces. Herein, the interaction of N-terminal histidine-tag-modified capsid proteins with several metal ions is reported. Depending on the conditions used, nanometer-sized protein particles or capsidlike architectures are formed that are stable at pH 7.5. This metal-mediated stabilization methodology is employed to form stable capsids containing multiple proteins at pH 7.5, thereby greatly expanding the scope of the CCMV capsid as a nanoreactor. 相似文献
5.
Xin Zhao Antal A. Koos Bryan T.T. Chu Colin Johnston Nicole Grobert Patrick S. Grant 《Carbon》2009,47(3):561-569
High performance perfluoro alkoxy (PFA) and chemical vapor deposition-grown multi-walled carbon nanotube (MWCNT) composite films with thicknesses of 30 μm were prepared using a scalable spray deposition technique. A homogeneous distribution of MWCNTs within the PFA matrix was confirmed by electron and optical microscopy. Dielectric and AC conductivity measurements showed a significant enhancement of dielectric permittivity for PFA/MWCNT films at low frequencies, and a very weak dependence of dielectric permittivity on temperature in the range 25-230 °C. Very low percolation threshold volume fractions of ca. 0.0043 and 0.0017 were attained for MWCNTs with two different aspect ratios, which have been explained by an inherent feature of spray route, a microcapacitor model and percolation theory. The combination of PFA/MWCNT composites and the spray deposition route provides a promising approach for the fabrication of industrial scale composite films with well-controlled dielectric properties for micro-electronic and high temperature applications. 相似文献
6.
Britta Marko Paulina Heurich Patrick Thon Frieda Zimmer Lars Bergmann Hartmuth Nowak Katharina Rump Bjrn Koos Michael Adamzik Matthias Unterberg Tim Rahmel 《International journal of molecular sciences》2022,23(14)
The functionally important NF-κB1 promoter polymorphism (−94ins/delATTG) significantly shapes inflammation and impacts the outcome of sepsis. However, exploratory studies elucidating the molecular link of this genotype-dependent pattern are lacking. Accordingly, we analyzed lipopolysaccharide-stimulated peripheral blood mononuclear cells from both healthy volunteers (n = 20) and septic patients (n = 10). All individuals were genotyped for the −94ins/delATTG NF-κB1 promoter polymorphism. We found a diminished nuclear activity of the NF-κB subunit p50 in ID/DD genotypes after 48 h of lipopolysaccharide stimulation compared to II genotypes (p = 0.025). This was associated with higher TNF-α (p = 0.005) and interleukin 6 concentrations (p = 0.014) and an increased production of mitochondrial radical oxygen species in ID/DD genotypes (p = 0.001). Although ID/DD genotypes showed enhanced activation of mitochondrial biogenesis, they still had a significantly diminished cellular ATP content (p = 0.046) and lower mtDNA copy numbers (p = 0.010) compared to II genotypes. Strikingly, these findings were mirrored in peripheral blood mononuclear cells taken from septic patients. Our results emphasize the crucial aspect of considering NF-κB subunits in sepsis. We showed here that the deletion allele of the NF-κB1 (−94ins/delATTG) polymorphism was associated with the lower nuclear activity of subunit p50, which, in turn, was associated with aggravated inflammation and mitochondrial dysfunction. 相似文献
7.
8.
A new anthropometric landmark of the face, called the maxillozygion (mz; right, left) is presented. The bilateral landmark is the most prominent point of the maxillozygomatic suture line, identified by palpation of the most anterior protruding contours on the frontal aspect of the face, located below the lateral third of the right and left bony orbits. The reliability of locating the landmark on both sides of the face by palpation is discussed. Preliminary data determining the position of the maxillozygion in the vertical, sagittal, and horizontal planes in white and Asian sample populations is presented. In general, the Asian face tends to be the same width (zygion [zy]-zy) as the white face; however, the maxillozygion is located more laterally on the Asian face compared with the white face. 相似文献
9.
10.
K Roessler K Ungersboeck M Aichholzer W Dietrich H Goerzer C Matula T Czech WT Koos 《Canadian Metallurgical Quarterly》1998,49(3):282-8; discussion 288-9
BACKGROUND: The Zeiss MKM System is a recently developed computerized operating microscope for image-guided neurosurgery. The clinical advantages, reliability, accuracy, and limitations of this technique were investigated. METHODS: Since February 1995, 78 consecutive frameless stereotactic image-guided procedures were performed in 73 patients (30 males, 43 females; mean age, 46.9 years; range, 16-77 years) for tumor surgery (50/64.1%), cavernoma removal (16/20.5%), and functional procedures (12/15.4%). Skin markers (74 cases) or bone markers (4 cases) and a standard imaging protocol (2-mm cranial computed tomography (CCT) in 59 cases/1.5-mm magnetic resonance imaging (MRI) in 19 cases) were used. RESULTS: The main advantages were pre-operative skin incision, craniotomy and corticotomy planning, and determination of lesion boundaries. Useful registration and system reliability were noted in 97% (76/78) of the procedures. A significant improvement in registration accuracy was observed over the test period from a mean of 4.8 mm (SD = 3.36; Cases 1-25) to a mean of 2.2 mm (SD = 0.86; Cases 26-78). This resulted in an improvement in application accuracy from <5 mm in 71% (Cases 1-25) to <2 mm in 95% (Cases 26-78) of cases, and the accuracy led to successful localization of the lesion in every case. Accuracy was reliable at the beginning of every procedure, but degraded to values >5 mm by the end of the procedure in 29% (22/78) of cases. MRI cases achieved higher application accuracy values (2.1 mm mean) than CT cases (3.7 mm mean). CONCLUSIONS: The system offers a reliable alternative to frame-assisted stereotactic craniotomies in lesion targeting, but would need an intraoperative image update for resection guidance. 相似文献