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31.
Male rats have been observed to display erections when exposed to inaccessible estrous females, and it was suggested that these "noncontact erections" (NCEs) represent a species-typical response that may index sexual arousal. Initial efforts in other laboratories to repeat and extend this research were unsuccessful, and it appeared that differences in the rat strains being used might be responsible. To address this question NCE tests were given to rats of two albino strains, Wistar and Sprague-Dawley, and two pigmented strains, hooded Long-Evans and inbred Brown Norway. A high proportion of Long-Evans and Brown Norway rats displayed NCEs, whereas Wistar and Sprague-Dawley albino rats rarely did. Additional experiments did not reveal the reasons for the strain difference in NCE, but they provided evidence against hypotheses based on the relative erectogenic effect of albino and hooded estrous females, the attention paid to estrous females, the motor repertoire, or erectile function per se. Albinism-related neural pathology, possibly outside of the visual system, may contribute to the deficit in NCE in albino rats.  相似文献   
32.
The TR1C fragment of turkey skeletal muscle TnC (residues 12-87) comprises the two regulatory calcium binding sites of the protein. Complete assignments of the 1H-NMR resonances of the backbone and amino acid side chains of this domain in the absence of metal ions have been obtained using 2D 1H-NMR techniques. Sequential (i,i+1) and short-range (i,i+3) NOE connectivities define two helix-loop-helix calcium binding motifs, and long-range NOE connectivities indicate a short two-stranded beta-sheet formed between the two calcium binding loops. The two calcium binding sites are different in secondary structure. In terms of helix length, site II conforms to a standard "EF-hand" motif with the first helix ending one residue before the first calcium ligand and the second helix starting one residue after the beta-sheet. In site I, the first helix ends three residues before the first calcium ligand, and the second helix starts three residues after the beta-sheet. A number of long-range NOE connectivities between the helices define their relative orientation and indicate formation of a hydrophobic core between helices A, B, and D. The secondary structure and global fold of the TR1C fragment in solution in the calcium-free state are therefore very similar to those of the corresponding region in the crystal structure of turkey skeletal TnC [Herzberg, O., & James, M.N.G. (1988) J. Mol. Biol. 203, 761-779].  相似文献   
33.
BACKGROUND: After-hours telephone calls are a stressful and frustrating aspect of pediatric practice. At the request of private practice pediatricians in Denver, a metropolitan area-wide system was created to manage after-hours pediatric telephone calls and after-hours patient care. This system, the After-Hours Program (AHP), uses specially trained pediatric nurses with standardized protocols to provide after-hours telephone triage and advice for the patients of 92 Denver pediatricians, representing 56 practices. OBJECTIVES: This report describes the AHP, presents data from 4 years' experience with the program, and describes results of our evaluation of the following aspects of the program: subscribing physician satisfaction, parent satisfaction, the accuracy and appropriateness of telephone triage, and program costs. METHODS: After-Hours Program records (including quality assurance data) for all 4 years of operation were retrospectively reviewed, tabulated, and analyzed. The results of two subscribing physician surveys and one parent caller satisfaction survey are presented. A retrospective review of after-hours patient care encounter forms assessed the necessity for after-hours visits triaged by the AHP. An analysis of the total cost of this program to 10 randomly selected subscribing physicians was conducted using current AHP data and a survey of the 10 physicians. RESULTS: In 4 years, 107,938 calls have been successfully managed without an adverse clinical outcome. Minor errors in using protocols occurred in one call out of 1450 after-hours calls. After-hours phoen calls necessitated an after-hours patient visit 20% of the time and generated one after-hours hospital admission out of every 88 calls. Just over half of the patients were managed with home care advice only, and 28% were given home care advice after-hours and seen the next day in the primary physician's office. Of all patients directed by the telephone triage nurses to be seen after hours, 78% were determined to have a condition necessitating after-hours care. Data are presented regarding call volumes by time of day, day of week, patient age, and patient's initial complaint. The 6 most common complaints accounted for more than one half of the calls, and 38 complaints accounted for more than 95% of all after-hours calls. Utilization by subscribing physicians is described. Satisfaction among subscribing pediatricians was 100%, and among parents was 96% to 99% on a variety of issues. The total cost to participating Denver pediatricians (which includes revenues "given up" as a result of not seeing patients after hours) ranged from 1% to 12% of their annual net income, depending on a variety of factors. CONCLUSIONS: Large-scale after-hours telephone coverage systems can be effective and well-received by patients, parents, and primary physicians. Data presented in this report can assist in planning the training of personnel who provide after-hours telephone advice and triage. Controversies associated with this type of program are discussed. Suggestions are made regarding the direction of future programs and research.  相似文献   
34.
Twenty infrequently reported species of gram-negative anaerobic bacilli other than Fusobacterium nucleatum, Fusobacterium necrophorum, and members of the genus Bacteroides were studied with regard to their role in infection and their susceptibility to antimicrobial agents. In addition, the literature regarding the recovery of these organisms from both the normal flora and infections of humans was reviewed. During a six-year period at the Wadsworth Clinical Anaerobic Bacteriology Research Laboratory (Veterans Administration Wadsworth Medical Center, Los Angeles, Calif.), 39 (6%) of 679 specimens obtained from anaerobic infections yielded "other gram-negative anaerobic bacilli" (OGNAB). Fusobacterium naviforme, Fusobacterium gonidiaformans, Fusobacterium varium, Fusobacterium mortiferum, and Fusobacterium russii were the most commonly isolated OGNAB. Most of the OGNAB tested were resistant to erythromycin, and most strains, except for F. varium, were susceptible to beta-lactam antibiotics and clindamycin. Chloramphenicol and metronidazole were active against all strains of OGNAB tested. Certain Fusobacterium species are undoubtedly previously unrecognized members of the normal flora of the oropharynx, upper respiratory tract, or urogenital tract and may be present in infections derived from these floras.  相似文献   
35.
"Stimulus-secretion" processes, and notably those in which the stimulus is provided by the formation of an antigen-antibody complex at the cell surface, require the presence of external Ca++. To test the possiblity that effector cells, in non-T cell mediated cytolysis, might be triggered to release a cytolytic product by a similar mechanism, we investigated the requirements of this phenomenon for divalent cations. We found that Ca++ is not sufficient, not necessary, and not inhibitory, whereas Mg++ is necessary and sufficient. Other cations were tested, and we found that Mn++ behaved like Mg++. The Ca++ data suggest that no conventional "stimulus-secretion" process is operative in non-T cell mediated cytolysis of antibody-coated sheep red blood cells.  相似文献   
36.
A time-of-flight trigger based on a time-to-amplitude converter and differential discriminator is described. The trigger has a short decision time (60 ns) and high (100%) efficiency of useful event selection.  相似文献   
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The last six months of 2001 and beginning of 2002 were a time of serious planned changes in foreign classifications of motor oils.  相似文献   
40.
The contributions of the various ulnar-innervated muscles of the hand to the hypothenar compound muscle action potential (CMAP) were estimated by directly stimulating individual muscles and by analyzing CMAP shape changes resulting from manipulations that changed individual muscle lengths. The results show that the first peak of the negative phase of the hypothenar CMAP comes from the hypothenar muscles, but that the second peak is due to a large volume-conducted potential from the interosseous muscles. The interosseous contribution affects both the amplitude and the area of the CMAP, and makes these parameters sensitive to changes in the configuration of the fingers and the temperature gradient in the hand. To reduce the interosseous contribution, a "balanced reference" consisting of two reference electrodes, one over each tendon, is proposed.  相似文献   
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