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71.
HE Bronheim G Fulop EJ Kunkel PR Muskin BA Schindler WR Yates R Shaw H Steiner TA Stern A Stoudemire 《Canadian Metallurgical Quarterly》1998,39(4):S8-30
This practice guideline seeks to provide guidance to psychiatrists who regularly evaluate and manage patients with medical illnesses. The guideline is intended to delineate the knowledge base, professional expertise, and integrated clinical approach necessary to effectively manage this complex and diverse patient population. This guideline was drafted by a work group consisting of psychiatrists with clinical and research expertise in the field, who undertook a comprehensive review of the literature. The guideline was reviewed by the executive council of the Academy of Psychosomatic Medicine and revised prior to final approval. Some of the topics discussed include qualifications of C-L consultants, patient assessment, psychiatric interventions (e.g., psychotherapy, pharmacotherapy), medicolegal issues, and child and adolescent consultations. 相似文献
72.
J. R. Yates K. J. Miller 《Fatigue & Fracture of Engineering Materials & Structures》1988,11(5):321-330
Abstract— A novel mixed-mode loading frame has been designed to fit a uniaxial servo-hydraulic test machine. The frame allows fatigue tests to be performed on circurnferentially slit round bars under combined in-phase torsion and bending loads at positive mean stresses. The growth of fatigue cracks was monitored using a direct current potential drop technique. An empirical equation relating crack depth and voltage is presented. 相似文献
73.
PJ Trotter WI Wu J Pedretti R Yates DR Voelker 《Canadian Metallurgical Quarterly》1998,273(21):13189-13196
In an effort to understand molecular mechanisms of intracellular lipid transport, we have focused upon specific events required for de novo aminophospholipid synthesis in the yeast Saccharomyces cerevisiae. A genetic system for examining the steps between phosphatidylserine (PtdSer) synthesis in the endoplasmic reticulum and its transport to and decarboxylation by PtdSer decarboxylase 2 in the Golgi/vacuole has been developed. We have isolated a mutant, denoted pstB1, that accumulates PtdSer and has diminished phosphatidylethanolamine formation despite normal PtdSer decarboxylase 2 activity. The lesion in PtdSer metabolism is consistent with a defect in interorganelle lipid transport. A genomic DNA clone that complements the mutation was isolated, and sequencing revealed that the clone contains the STT4 gene, encoding a phosphatidylinositol 4-kinase. The pstB1 mutant exhibits a defect in Stt4p-type phosphatidylinositol 4-kinase activity, and direct gene replacement indicates that STT4 is the defective gene in the mutant. Creation of an STT4 null allele (stt4Delta::HIS3) demonstrates the gene is essential. These results provide evidence that implicates phosphoinositides in the regulation of intracellular aminophospholipid transport. 相似文献
74.
SR Cummings DM Black DE Thompson WB Applegate E Barrett-Connor TA Musliner L Palermo R Prineas SM Rubin JC Scott T Vogt R Wallace AJ Yates AZ LaCroix 《Canadian Metallurgical Quarterly》1998,280(24):2077-2082
CONTEXT: Alendronate sodium reduces fracture risk in postmenopausal women who have vertebral fractures, but its effects on fracture risk have not been studied for women without vertebral fractures. OBJECTIVE: To test the hypothesis that 4 years of alendronate would decrease the risk of clinical and vertebral fractures in women who have low bone mineral density (BMD) but no vertebral fractures. DESIGN: Randomized, blinded, placebo-controlled trial. SETTING: Eleven community-based clinical research centers. SUBJECTS: Women aged 54 to 81 years with a femoral neck BMD of 0.68 g/cm2 or less (Hologic Inc, Waltham, Mass) but no vertebral fracture; 4432 were randomized to alendronate or placebo and 4272 (96%) completed outcome measurements at the final visit (an average of 4.2 years later). INTERVENTION: All participants reporting calcium intakes of 1000 mg/d or less received a supplement containing 500 mg of calcium and 250 IU of cholecalciferol. Subjects were randomly assigned to either placebo or 5 mg/d of alendronate sodium for 2 years followed by 10 mg/d for the remainder of the trial. MAIN OUTCOME MEASURES: Clinical fractures confirmed by x-ray reports, new vertebral deformities detected by morphometric measurements on radiographs, and BMD measured by dual x-ray absorptiometry. RESULTS: Alendronate increased BMD at all sites studied (P<.001) and reduced clinical fractures from 312 in the placebo group to 272 in the intervention group, but not significantly so (14% reduction; relative hazard [RH], 0.86; 95% confidence interval [CI], 0.73-1.01). Alendronate reduced clinical fractures by 36% in women with baseline osteoporosis at the femoral neck (>2.5 SDs below the normal young adult mean; RH, 0.64; 95% CI, 0.50-0.82; treatment-control difference, 6.5%; number needed to treat [NNT], 15), but there was no significant reduction among those with higher BMD (RH, 1.08; 95% CI, 0.87-1.35). Alendronate decreased the risk of radiographic vertebral fractures by 44% overall (relative risk, 0.56; 95% CI, 0.39-0.80; treatment-control difference, 1.7%; NNT, 60). Alendronate did not increase the risk of gastrointestinal or other adverse effects. CONCLUSIONS: In women with low BMD but without vertebral fractures, 4 years of alendronate safely increased BMD and decreased the risk of first vertebral deformity. Alendronate significantly reduced the risk of clinical fractures among women with osteoporosis but not among women with higher BMD. 相似文献
75.
A blind adaptive decorrelating detector for CDMA systems 总被引:6,自引:0,他引:6
The decorrelating detector is known to eliminate multiaccess interference when the signature sequences of the users are linearly independent, at the cost of enhancing the Gaussian receiver noise. We present a blind adaptive decorrelating detector which is based on the observation of readily available statistics. The algorithm recursively updates the filter coefficients of a desired user by using the output of the current filter. Due to the randomness of the information bits transmitted and the ambient Gaussian channel noise, the filter coefficients evolve stochastically. We prove the convergence of the filter coefficients to a decorrelating detector in the mean squared error (MSE) sense. We develop lower and upper bounds on the MSE of the receiver filter from the convergence point and show that with a fixed step size sequence, the MSE can be made arbitrarily small by choosing a small enough step size. With a time-varying step size sequence, the MSE converges to zero implying an exact convergence. The proposed algorithm is distributed, in the sense that no information about the interfering users such as their signature sequences or power levels is needed. The algorithm requires the knowledge of only two parameters for the construction of the receiver filter of a desired user: the desired user's signature sequence and the variance of the additive white Gaussian (AWG) receiver noise. This detector, for an asynchronous code division multiple access (CDMA) channel, converges to the one-shot decorrelating detector 相似文献
76.
OBJECTIVE: Changes in the health care environment have placed a greater responsibility on psychiatrists to deliver basic primary care services. The study assessed baseline knowledge and attitudes about clinical preventive medical services among psychiatric faculty and psychiatric residents at a tertiary care medical center. METHODS: Residents and faculty in psychiatry and general internal medicine completed a structured questionnaire, including 20 case scenarios, that assessed their baseline knowledge of clinical preventive medical services, their attitudes concerning delivery of those services, and their beliefs about the effectiveness of those services in changing patients' behavior. The case scenarios and knowledge questions were based on the clinical preventive medical services recommendations outlined by the U. S. Preventive Services Task Force. RESULTS: Psychiatrists reported more frequent assessment of and counseling about the use of illicit drugs and weapons, and internists were more likely to query about measures related to physical health such as cancer screening and immunizations. The two groups reported similar attitudes toward the need for and the efficacy of preventive medical services. Commonly cited barriers to the delivery of preventive care included lack of time and education. Psychiatrists scored reasonably well on baseline knowledge about guidelines for preventive medical services, particularly given their recent lack of specific education in these matters. CONCLUSIONS: Psychiatrists believe clinical preventive services are important and express interest in their delivery. Additional educational interventions are needed to train psychiatrists in clinical preventive services to avoid missed clinical opportunities for intervention in psychiatric populations that may have poor access to other medical care. 相似文献
77.
A family of binary sequences exists with the property that the cross-correlation function of each member with a reference m-sequence has a unique pattern of four peaks with equal offsets from a constant base level. The positive peak is position invariant and knowledge of the locations of the remaining three peaks, which are negative, identifies the sequence. A simple method for generating the sequences is given and an application in the form of a system for data transmission by code modulation of an m-sequence carrier is proposed. 相似文献
78.
79.
We define complex systems, from molecular ensembles and networks to galactic clusters, as fluid-plastic-elastic systems in which bulk/shear viscosity ratios are large, with the consequence that interactions among parts at any level lead to internalization of action (energy × time) and to variable process delays between external inputs and outputs. Living systems are notably complex by this measure. Complex systems can be comprehended dynamically through an extended statistical mechanics, irreversible thermodynamics, and nonlinear mechanics, in the form of an electrohydrodynamic field physics. Chemical reactivity (making, breaking, or exchanging bonds) is subsumed in the generalized mechanics as a diffusive process. In this paper we apply this physical construct to the problems of dynamic regulation and coordination among parts in the forms of life found in the more than 300 families of flowering plants. We choose to use these particular plants rather than vertebrates, mammals, or man, as exemplars of our theory to show how effective “chemical languages” can be, without the obfuscating arrangements of nervous systems and muscles designed to support locomotion. 相似文献
80.
Stable isotope-enriched molecules are used as internal standards and as tracers of in vivo substrate metabolism. The accurate conversion of measured ratios in the mass spectrometer to mole ratios is complicated because a polyatomic molecule containing enriched atoms will result in a combinatorial distribution of isotopomers depending on the enrichment and number of "labeled" atoms. This effect could potentially cause a large error in the mole ratio measurement depending on which isotope peak or peaks were used to determine the ratio. We report a computational method that predicts isotope distributions over a range of enrichments and compares the predicted distributions to experimental peptide isotope distributions obtained by Fourier transform ion cyclotron resonance mass spectrometry. Our approach is accurate with measured enrichments within 1.5% of expected isotope distributions. The method is also precise with 4.9, 2.0, and 0.8% relative standard deviations for peptides containing 59, 79, and 99 atom % excess (15)N, respectively. The approach is automated making isotope enrichment calculations possible for thousands of peptides in a single muLC-FTICR-MS experiment. 相似文献