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11.
Prediction equations for estimating lung volumes have been determined for Caucasians, African-Americans, and Mexican-Americans. These separate equations were determined because of differences in thoracic morphology between people of various racial groups, making it impossible to use one prediction formula to accurately estimate lung volumes for all individuals. One hundred ninety-one adolescent Navajo children (males, n = 110; females, n = 81) between 11 and 18 yr of age volunteered for the study and underwent a series of pulmonary function tests (PFT). New pulmonary function prediction equations for Navajo youth were generated for estimating pulmonary volumes and capacities that more accurately predict expected PFT outcomes than formulas in common use for Caucasian, Mexican-American, or African-American youth. 相似文献
12.
Oligonucleotide N3'-->P5' phosphoramidates (3'-phosphoramidates) are DNA analogs that are presently under investigation as potential therapeutic agents. These compounds may also hold promise as a diagnostic tool. Here, we describe a rapid method for the analysis of single-stranded RNA fragments utilizing 3'-phosphoramidate oligonucleotides as probes in conjunction with capillary gel electrophoresis (CGE). 3'-Phosphoramidate 9-mers were mixed with complimentary RNA, and CGE was used to monitor duplex formation. Complimentary strands of RNA and 3'-phosphoramidate formed duplexes that gave unique relative mobilities based on an internal standard. The ability of CGE to discriminate between perfect duplexes and duplexes that contain a base mismatch was also investigated. However, the primary focus of this work was to determine CGE's ability to detect the presence of the 3'-phosphoramidates/RNA duplex under routine electrophoretic running conditions. Polyacrylamide gel electrophoresis analysis was utilized to verify duplex formation. 相似文献
13.
Contamination of enteral diets may play an essential role in formula tolerance and safety for patients. Contaminated enteral formula commonly support microbiological growth. Commercially sterile liquid formulas received from the manufacturer are required by the Food & Drug Administration (FDA) to be shelf-stable and free from enteric pathogens. This study examined the use of large volume, closed system containers in a typical nursing home. Large volume (1500 mL) containers with unique pierceable caps and piercing spikes were studied to determine their ability to reduce the incidence of microbiological contamination due to their design and ability to decrease handling requirements. This study took place in a room of a typical nursing home. In this clinical setting, 211 containers and administration spike sets were evaluated following a 36-h hangtime. Contamination was virtually nondetectable. Nursing staff in a clinical facility can effectively utilize a large volume, prefilled, ready-to-use feeding system to achieve delivery of noncontaminated product for up to 36 h hangtime. 相似文献
14.
W. R. Vogler A. C. Olson S. Okamoto M. Shoji R. L. Raynor J. F. Kuo W. E. Berdel H. Eibl J. Hajdu H. Nomura 《Lipids》1991,26(12):1418-1423
Alkyl lysophospholipids have been shown to be cytooxic to a number of neoplastic tissues. One, ET-18-OCH3, has been used to selectively purge leukemic cells from mixtures with normal marrow progenitor cells,in vitro andin vivo. We have measured the 50% inhibitory (IC50) effect of a series of ether, lipids (EL) on leukemic cells (HL60, K562, Daudi, KG-1, KG-1a) and normal marrow progenitor
cells. Cells were incubated with varying concentrations of EL for 4 hr and assayed for viability, [3H]thymidine incorporation and clonogenicity in semi-solid media. The effect on protein kinase C (PKC) activity was assayed
for each compound. Compounds tested included three glycerophosphocholine analogs-ET-18-OCH3, ET-16-NHCOCH3, and BM 41.440. In addition, a lipoidal amine, CP 46665, an ethyleneglycolphospholipid, AEPL, and four single chain alkylphosphocholine
analogs, HePC2, HePC3, HePC4 and HePC6 were also tested. During the period of incubation, the cells remained viable (>70%) as judged by trypan blue dye exclusion.
The glycerophosphocholines were the most active and showed the highest therapeutic index. The lipoidal amine was active, but
toxic to normal marrow progenitor cells. The ethyleneglycolphospholipid was active against HL60, but not against the other
cell lines. The single chain alkylphosphocholine analogs were less active. All of the compounds inhibited PKC activity; however,
the glycerophosphocholines were the most inhibitory.
Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl
Ether Lipids, Tokyo, Japan, May 1989. 相似文献
15.
A series of new alkene and octenyloxy monomers containing 4′-[oligo(ethylene oxide)] n monomethyl ether 4-biphenyl ether carboxyl benzoate [MS3BDBEn] (n = to 3) and 1- (p-methoxydiphenyl)–(carboxyl benzoate) [oligo(ethylene oxide)]n [MSm+2BEnDB] (m = 1, 6; n = 1 to 3) as end groups were synthesized. The molecular structure of the monomers was charaterized using nuclear magnetic resonance (NMR) spectroscopy. These monomers were grafted onto poly(methylhydrosiloxane)s (PMHS) by the platinun-catalyzed hydrosilylation process. The thermal transition temeratures and mesophase textures of the monomers and the polysiloxane polymers have been determined by diffential scanning calorimetry (DSC) and by polarized optical microscopy. The effect of changes in chemical structure on the mesophase properties, glass transition temperature, isotropic temperature, and mesophase texture of the monomers and the polysiloxane polymers is discussed. Polymers PS3BDBEn showed smectic and nematic phases which were not analogous to their precursor nematic monomers MS3BDBEn. Both monomers MSm+2BEnDB and their polymeric homologous PSm+2BEnDB did not exhibit mesophase properties. This demonstrated that the polymer effect could not stabilize the mesophase obtained from mesogenic core which contained a flexible oligo(ethylene oxide) unit interconnecting aromatic group. © 1995 John Wiley & Sons, Inc. 相似文献
16.
<正>作者等过去的工作已经证实,由于扩散过程的影响、温度范围的不同、或化学组成的差异,二氧化硫在钒催化剂上的氧化动力学方程式可能具有不同的形式。反应物及生成物与催化剂之间的相互作用,可能使催化剂具有不同的颜色与活性,因而即使温度相同,由于催化剂在层内所处的部位不同,其催化活性可能并不一致。这些复杂性给工业设计带来了很大的困难。因此,合理的简化是完全必要的。 作者等选取了几种不同的工业钒催化剂,用实验方法求得了适用于它们的动力学方程式,进行比较和讨论,提出了一个简便的、合理的、可以用作设计基础的动力学方程式。 相似文献
17.
Multimedia Tools and Applications - Rate distortion optimization technique is adopted by H.264/AVC to select the best intra and inter prediction modes. It achieves remarkable improvement in... 相似文献
18.
MD Ercegovac N Vojvodi? Soki?DV SM Jankovi? J Drulovi? N Stojsavljevi? Z Levi? 《Canadian Metallurgical Quarterly》1998,126(9-10):335-344
CONCLUSION: We conclude that despite inevitable variability the clinical picture of JME is characteristic. It is easy to diagnose JME if one thinks of it while the history should be thoroughly analyzed. An EEG recording during sleep confirms the diagnosis. An early diagnosis of JME permits adequate prognosis of the subsequent course of epilepsy, and adequate therapy brings remission in most of the patients. If treatment starts following the large number of severe GTC seizures, the response to therapy is incomplete. The persistency of the illness throughout the life, the need for continuous medication and therapeutic unresponsiveness in cases with late diagnosis, do not justify the increasing misconception that JME is of benign nature. Diagnosis of JME is rare because of insufficient familiarily of physicians with the illness. BACKGROUND: Juvenile myoclonic epilepsy (JME) is an idiopathic generalized epileptic syndrome characterized with the combination of myoclonic, generalized tonic-clonic (GTC) and absence seizures that are readily provoked by sleep deprivation. PATIENTS: Forty-three patients, aged from 14 to 51 years, participated in a 5-year follow-up study. Diagnosis was made according to the criteria (Table 1) for diagnosis of JME set by Panayiotopoulos et al. (1994). Nineteen patients made their first contact with a neurologist at the Institute of Neurology and were diagnosed as JME, while the remaining 24 were referred to from other medical institutions with a diagnosis of therapy resistant to focal epilepsy. All patients underwent a somatic and neurological examination, "mini mental test," EEG in waking and CT scan of the brain. Some patients had EEG performed during sleep and some had MRI of the head. RESULTS: JME began between 9 and 26 (average 17) years. All patients had myoclonic seizures, 98% had GTC and 23% absence seizures. The first myoclonic seizure occurred between 9 and 24 years while the frst GTC seizure occurred between 10 and 32 years. Myoclonic seizures (83% of patients) and GTC seizures (70% of patients) occurred most often immediately after awaking. The most frequent provocative factors were insufficient sleep, alcohol abuse and tiredness. Epilepsy in the family was present in 39%, focal neurological deficiency in 9% and pathological findings on of CT and MRI in 7% of patients. Waking EEG was pathological in 77% of patients; it included generalized spike-wave discharges in 73%, multiple spike-wave complexes in 33% and focal discharges in 12% of patients, respectively. In all 26 patients tested, sleep EEG was pathological most often with multiple spike-wave complexes in 85% and 3-4 Hz spike-wave complexes in 57% of patients. The correct diagnosis of JME following a comprehensive examination was made in 24 (56%) patients after a delay of 1 to 35 years. In 24 patients with delayed diagnosis of JME the replacement of earlier medication with valproic acid (VPA) induced remission in 18 patients (75%) while 1 patient (4%) experienced a reduction in the number of seizures. Five patients (21%) did not respond to VPA medication: 2 due to a weak compliance, another 2 due to inefficient medication and 1 because of the preexistent malabsorption syndrome. In 19 patients (44%) with initial diagnosis of JME, VPA was introduced immediately upon diagnosis. Of them, 15 (79%) had excellent response to VPA, 1 refused therapy and for 3 patients there is no information. In 2 patients VPA was substituted due to side effects (hepatotoxicity and alopetia) with lamotrigine (low doses), which brought about decrease in frequency and mitigation in myoclonic seizures. 相似文献
19.
Reliable methods of estimating doses are essential for the use of beta emitting radionuclides for radiotherapy. The passage of electrons through matter is a very complex phenomenon due to the large number of elastic and inelastic interactions resulting in scattering and energy losses. The analytical solution for the electron transport being intractable, the problem has been addressed by the Monte Carlo technique. Empirical or semiempirical less time consuming methods, such as the scaling factor method, may appear more preferable in practice when dealing with complicated source distributions. The method, proposed by Cross and co-workers [AECL Report Nos. AECL-1617 (1982), AECL 10521 (1992)] consists in the derivation of beta-ray dose distribution in other media from those in water by using a "scaling factor" or "relative attenuation factor" on distance and a closely related renormalization factor imposed by the energy conservation. This work investigates the accuracy of the scaling factor method using a statistical approach, a generalized chi 2 test, focusing on the particular case of potential interest, the scaling factor for water to bone. The direct comparison of the shapes of the depth dose deposition curves in the two media indicates discrepancies of less than 5% up to at least 60% of the range in bone, a depth within which 95% of the initial energy is deposited. The scaling factor derived by this method, 0.9720 +/- 0.0012, confirms the existing experimentally determined value of 0.973 +/- 1% [AECL Report No. AECL-10521 (1992)]. The accuracy of the determination is increased by almost a factor of 10. A way of improving the scaling method, especially for depth over the 60% continuous slowing down approximation range, by using a modulation function is also proposed. 相似文献
20.
In this study, an adaptive fuzzy time series model for forecasting Taiwan’s tourism demand is proposed to further enhance the predicted accuracy. We first transfer fuzzy time series data to the fuzzy logic group, assign weights to each period, and then use the proposed adaptive fuzzy time series model for forecasting in which an enrollment forecasting values is applied to obtain the smallest forecasting error. Finally, an illustrated example for forecasting Taiwan’s tourism demand is used to verify the effectiveness of proposed model and confirmed the potential benefits of the proposed approach with a very small forecasting error MAPE and RMSE. 相似文献