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21.
Idiopathic adhesive capsulitis usually responds to gentle physical therapy or, if that fails, to closed manipulation with the patient under anesthesia. In some patients, however, loss of motion may be refractory to either of these treatments and an operative release may be indicated. We are reporting on the technique and results of arthroscopic capsular release as a new alternative for the management of such patients. During a three-year period, we managed twenty-three patients who had idiopathic adhesive capsulitis that had failed to respond to physical therapy or closed manipulation. These patients had an arthroscopic anterior capsular release and received forty-eight hours of intensive physical therapy as inpatients. During the physical therapy, the patients received an interscalene regional analgesic with use of repeated nerve blocks or with a continuous infusion through an interscalene catheter. This was followed by a supervised outpatient physical-therapy program. Six patients also had an arthroscopic acromioplasty for the treatment of impingement. There were no complications related to any of the procedures. At a mean of thirty-nine months (range, twenty-four to sixty-four months) after the arthroscopic procedure, the improvement in the score of Constant and Murley averaged 48 points (range, 13 to 77 points). The mean improvement in motion was 49 degrees (range, 0 to 105 degrees) for flexion; 42 degrees (range, 10 to 80 degrees) and 53 degrees (range, 0 to 100 degrees) for external rotation in adduction and abduction, respectively; and eight spinous-process levels (range, three to fourteen levels) and 33 degrees (range, 30 to 60 degrees) for internal rotation in adduction and abduction, respectively. These gains in motion were all significant (p < 0.01) compared with the preoperative values and were within a mean of 7 degrees of the values for the contralateral, normal shoulder. We concluded that, in patients who have loss of motion that is refractory to closed manipulation, arthroscopic capsular release improves motion reliably with little operative morbidity.  相似文献   
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Organolanthanides are highly efficient catalysts for inter- and intramolecular hydroamination of various C-C unsaturations such as alkenes, alkynes, allenes, and dienes. Attractive features of organolanthanide catalysts include very high turnover frequencies and excellent stereoselectivities, rendering this methodology applicable to concise synthesis of naturally occurring alkaloids and other polycyclic azacycles. The general hydroamination mechanism involves turnover-limiting C-C multiple bond insertion into the Ln-N bond, followed by rapid protonolysis by other amine substrates. Sterically less encumbered ligand designs have been developed to improve reaction rates, and metallocene and nonmetallocene chiral lanthanide complexes have been synthesized for enantioselective hydroamination.  相似文献   
24.
We demonstrate in vivo optical coherence tomography using a Fourier-domain optical delay line constructed with a commercially available polygonal scanner. The 20-faceted polygonal mirror array, capable of scanning at rates up to 15 kHz, is implemented at 4 kHz to acquire 500 x 500 pixel images at 8 frames/s with a signal-to-noise ratio of 80 dB. Features of this delay line include scalability to high repetition rates, 98.6% linearity in group delay over 2 mm, and bandwidth support exceeding 150 nm. Images are obtained in an animal model (Xenopus laevis), and limitations due to phase-delay nonlinearity and polygon asymmetry are discussed.  相似文献   
25.
Larry Marks 《EDPACS》2013,47(2):17-18
Abstract

Telecommunications Management, Control, and Audit, by Bernard Plagman and Anne O'Laughlin. Altamonte Springs FL: The Institute of Internal Auditors Research Foundation, 1988, 207 pp, $45.00 (order item 776). (Discount available to IIA members).

Handbook for Information Security: A Guide Toward Information Security Standards, by J.C.H. Aalders, I.S. Herschberg, A. van Zanten, A. Augustinus, J. Brouwer, C.A. Hendricks, H. Onderstal, and C.J. Dickerson. New York: North Holland, 1985, 761 pp, $175.

The Complete Guide to Software Testing, second ed, by Bill Hetzel. Wellesley MA: QED Information Sciences, 1988, 280 pp, $24.95.  相似文献   
26.
Acetylcholine has been implicated as an important neurotransmitter in the mechanisms of thalamic activation. Cholinergic mechanisms are thought to directly underlie the high level of excitability observed in thalamic relay neurons during waking and rapid eye movement sleep. We sought to determine if the cholinergic responsiveness of neurons in the ventroposterior nuclei of the thalamus in rat is consistent with this view. Neurons in the chloral hydrate-anesthetized rat were studied with extracellular recording and microiontophoretic application of cholinergic agents. In most cases (63% of 63 cells), the ejection of the agonist, carbachol, had no observable effect on spontaneous activity. Facilitation (25%), inhibition (8%) and inhibition followed by facilitation (3%) were also observed. Carbachol ejections that by themselves were ineffective in altering spontaneous activity proved capable, in 93% of 28 cells, of antagonizing the uniformly facilitatory responses produced by glutamate ejection. The putative M1-selective, cholinergic agonist, McN-A-343, was also ineffective alone in altering spontaneous activity in the majority of cases (74% of 27 cells) and produced only inhibitory responses in the remaining seven neurons studied. Interacting applications of McN-A-343 and glutamate resulted, in all cases, in antagonism of glutamate facilitation (N = 12). The various responses to applied cholinergic agonists were all capable of being antagonized by muscarinic receptor-blocking agents. Both the high proportion of inhibitory responses and the antagonism of glutamate facilitatory responses suggest that ventroposterior neurons in the rat differ from other thalamocortical relay neurons in the rat and cat with regard to cholinergic responsiveness. Additionally, the lack of predominantly facilitatory responding renders it unlikely that cholinergic mechanisms directly underlie increases in excitability of ventroposterior neurons observed during waking and rapid eye movement sleep.  相似文献   
27.
The Lewis acid initiated cationic homopolymerization of Norway fish oil ethyl ester (NFO) or the corresponding conjugated fish oil (CFO) and their copolymerization with various alkene comonomers is investigated. Among the Lewis acids employed, boron trifluoride diethyl etherate (BFE, BF3 · OEt2) is found to be the most effective initiator for cationic polymerization of the NFO and CFO systems. The BFE‐initiated homopolymerization of NFO generally results in low molecular weight viscous oils, while that of CFO leads to a solid elastic gel with a gel time of more than 72 h at room temperature. Copolymerization of the NFO or CFO with some alkene comonomers significantly facilitates gelation. The gel times are largely dependent upon the stoichiometry, the type of fish oil, and the alkene comonomer. After postcuring at elevated temperatures, the cationic copolymerization affords polymers ranging from soft rubbery materials to rigid plastics. These NFO and CFO polymers are composed of highly crosslinked materials and a certain amount of free oils and are found to be fully cured thermosets. Generally, CFO polymers appear to be harder than the corresponding NFO polymers. However, the thermal properties of the bulk polymers are similar to each other, and their insoluble extracts exhibit much higher thermal stability than the bulk thermosets. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2001–2012, 2001  相似文献   
28.
29.
Simian virus 40 (SV40) DNA replication requires the coordinated action of multiple biochemical activities intrinsic to the virus-encoded large tumor antigen (T antigen). We report the preliminary biochemical characterization of the T antigens encoded by three SV40 mutants, 5030, 5031, and 5061, each of which have altered residues within or near the ATP binding pocket. All three mutants are defective for viral DNA replication in cultured cell lines. However, while 5030 and 5031 can be complemented in vivo by providing a wild-type T antigen in trans, 5061 exhibits a strong trans-dominant-negative phenotype. In order to determine the basis for their replication defects and to explore the mechanisms of trans dominance, we purified the T antigens encoded by each of these mutants and examined their activities in vitro. The 5061 T antigen had no measurable ATPase activity and failed to hexamerize in response to ATP, and its affinity for the SV40 origin of DNA replication (ori) DNA was not increased by ATP. In contrast, the 5030 and 5031 T antigens exhibited at least some ATPase activity and both readily formed hexamers in the presence of ATP. These mutants differed in that 5030 was very defective in an ori-dependent unwinding assay while 5031 retained significant activity. Both the 5030 and 5031 T antigens bound to ori-containing DNA, but the binding was less efficient than that of wild-type T antigen and was not affected by the presence of ATP. These results suggest that 5030 and 5031 are defective in some aspect of communication between the ATP binding and DNA binding domains and that the ability of ATP to induce T-antigen hexamerization is distinct from its action to increase the affinity for ori. Finally, all three mutants were defective for the ability to support SV40 DNA replication in vitro. Both the 5031 and 5061 T antigens inhibited wild-type-T-antigen-stimulated replication in vitro, while the 5030 T antigen did not. The fact that the 5031 T antigen was trans dominant in the in vitro assays but not in vivo indicates that the in vitro system does not accurately reflect events occurring in vivo.  相似文献   
30.
[Correction Notice: An erratum for this article was reported in Vol 103(1) of Psychological Bulletin (see record 2008-10686-001). The block quotation on page 73 should be attributed to Crocker (1981). The two sentences immediately preceding this quotation should read: 'Friendship groups typically exhibit a high degree of internal similarity with respect to members' beliefs, attitudes, values, and interests. Crocker (1981) reported the following:".] Ten years of research on the false-consensus effect (Ross, Greene, & House, 1977) and related biases in social perception (e.g., assumed similarity and overestimation of consensus) are examined in the light of four general theoretical perspectives: (a) selective exposure and cognitive availability, (b) salience and focus of attention, (c) logical information processing, and (d) motivational processes. The findings indicate that these biases are influenced by a host of variables and that no single explanation can account for the range of data. Instead, each theoretical perspective appears to have its own domain of application, albeit with some degree of overlap into other domains. The data further suggest that two or more specific mechanisms may operate simultaneously or in concert to produce assumed similarity and false-consensus effects. Discussion focuses on identifying the process or sets of processes operating in specific situations. We identify several gaps in the knowledge of mediating relationships and suggest directions for future research. We also discuss issues related to definition and measurement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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