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981.
This article discusses the importance of cultural sensitivity in providing nursing services to Native Americans. This necessitates general information about cultural universals that transcend specific tribes as well as cultural-specific knowledge. Cultural sensitivity also requires an understanding of the centuries-long oppression of Native Americans and their cultures by the dominant society.  相似文献   
982.
Large arrays of multifunctional rolled-up semiconductors can be mass-produced with precisely controlled size and composition, making them of great technological interest for micro- and nano-scale device fabrication. The microtube behavior at different temperatures is a key factor towards further engineering their functionality, as well as for characterizing strain, defects, and temperature-dependent properties of the structures. For this purpose, we probe optical phonons of GaAs/InGaAs rolled-up microtubes using Raman spectroscopy on defect-rich (faulty) and defect-free microtubes. The microtubes are fabricated by selectively etching an AlAs sacrificial layer in order to release the strained InGaAs/GaAs bilayer, all grown by molecular beam epitaxy. Pristine microtubes show homogeneity of the GaAs and InGaAs peak positions and intensities along the tube, which indicates a defect-free rolling up process, while for a cone-like microtube, a downward shift of the GaAs LO phonon peak along the cone is observed. Formation of other type of defects, including partially unfolded microtubes, can also be related to a high Raman intensity of the TO phonon in GaAs. We argue that the appearance of the TO phonon mode is a consequence of further relaxation of the selection rules due to the defects on the tubes, which makes this phonon useful for failure detection/prediction in such rolled up systems. In order to systematically characterize the temperature stability of the rolled up microtubes, Raman spectra were acquired as a function of sample temperature up to 300°C. The reversibility of the changes in the Raman spectra of the tubes within this temperature range is demonstrated.  相似文献   
983.
Tuberculous meningitis (TBM) remains common in Hong Kong. From January 1996 to June 1997, 11 adult patients with TBM presented to Queen Mary Hospital, a regional hospital in Hong Kong. The annual incidence of TBM was estimated at 1.8 per 100,000 population. Nine patients were local Chinese, and only one patient had the acquired immune-deficiency syndrome (AIDS). In contrast to the classical presentation as a chronic indolent disease, our patients presented acutely: the mean duration from onset of symptoms to presentation was 4.8 days (range 0-10). The most common presenting symptoms were headache (64%), fever (46%), or both (36%), with focal deficits occurring in 64% of patients. Cerebrospinal fluid (CSF) culture and polymerase chain reaction (PCR) were positive in 30% and 29% of cases. Mean CSF cell count, protein and glucose levels were 340 x 10(6)/L, 267 mg/dL, and 2.3 mmol/L, respectively. Extra-neural tuberculosis occurred in 46% of cases. All patients survived and responded to treatment. Drug-induced hepatotoxicity was common; 64% of patients developed biochemical hepatitis.  相似文献   
984.
Shoots of higher plants grow upward in response to gravity. To elucidate the molecular mechanism of this response, we have isolated shoot gravitropism (sgr) mutants in Arabidopsis thaliana. In this report, we describe three novel mutants, sgr4-1, sgr5-1 and sgr6-1 whose inflorescence stems showed abnormal gravitropic responses as previously reported for sgr1, sgr2 and sgr3. These new sgr mutations were recessive and occurred at three independent genetic loci. The sgr4-1 mutant showed severe defect in gravitropism of both inflorescence stem and hypocotyl but were normal in root gravitropism as were sgr1 and sgr2. The sgr5-1 and sgr6-1 mutants showed reduced gravitropism only in inflorescence stems but normal in both hypocotyls and roots as sgr3. These results support the hypothesis that some mechanisms of gravitropism are genetically different in these three organs in A. thaliana. In addition, these mutants showed normal phototropic responses, suggesting that SGR4, SGR5 and SGR6 genes are specifically involved in gravity perception and/or gravity signal transduction for the shoot gravitropic response.  相似文献   
985.
A discontinuous or thin cement mantle of a socket is associated with increased polyethylene wear and cement fractures. In a retrospective radiological analysis we examined the quality of the cement mantle in cups without (group I = 100 Charnley-Mueller cups) and with (group II = 100 Contemporary cups, Howmedica) bone cement spacers. Under-filling (0-2 mm) and over-filling (> 8 mm) of the cement mantle were noted and classified. Statistics show significantly less under-filling of the cement mantle in group II than in group I (P = 0.001), in particular when comparing separate cup regions (thirds: P < 0.001). Furthermore, there is no significant difference in the frequency of overfilling with cement between groups I and II (P = 0.108). To sum up, utilization of an acetabular component with performed bone cement spacers considerably improves the quality of the cement mantle without additional cost.  相似文献   
986.
Clinical observation suggests that deformities of the foot and ankle are common in children with cerebral palsy. Two hundred children with cerebral palsy attending the Central Remedial Clinic were examined and photographed. The children had no previous surgical intervention and were between 1.5 and 19 years of age. Deformities were assessed and related to the type of cerebral palsy and mobility status.  相似文献   
987.
Insulin and growth factors elicit rapid increases in protein synthesis by stimulating mRNA translation. PHAS/4E-BPs, a recently discovered family of elF4E-binding, proteins, appear to play a key role in this process, as well as in the control of cell proliferation.  相似文献   
988.
1. Male rats given daily intraperitoneal injections of fluoxetine (10 mg/kg) were slower to escape foot shock by jumping a low barrier. 2. When switched to a shuttle task requiring two crosses to terminate shock, the FLU-treated animals failed to learn in 55 trials. 3. A second experiment found FLU-treated animals could learn a one-way avoidance response, but were significantly slower to learn than control animals. 4. FLU-treated animals were no different than controls on tests of sensory thresholds for foot shock or heat. 5. Tests of motor behaviors revealed no differences in latency to traverse a narrow beam to reach a goal box, however FLU-treated animals were less active in an open field. 6. Several hypotheses can account for these data, the most promising being that a central motivational system (fear) is less active in FLU-treated animals.  相似文献   
989.
X-ray tubes having similar resolution capabilities along the central ray were compared for their wide-field characteristics. It has been suggested that focal spot size, and therefore resolution capability, along the cathode-anode axis may vary in a manner which is dependent upon the tube target angle. The authors show that differences beyond the effects of target angle occur, the extent of those differences varying from tube to tube. Although 2 different-sized focal spots may be adjusted to have equivalent central beam resolution capabilities, they can exhibit different imaging capabilities at wide-angle (off central axis) position. More than one parameter (equivalent focal spot size) is needed to characterize the behavior of a focal spot.  相似文献   
990.
The effects of local anesthetic agents (lidocaine, procaine, cocaine) and diphenylhydantoin (DPH) were studied on the slow electrical responses induced by isoproterenol or caffeine in cardiac muscle preparations rendered inexcitable by tetrodotoxin (TTX) or by partial depolarization with elevated K+ (26 mM). In such inexcitable cells, we previously demonstrated that addition of some positive inotropic agents, such as catecholamines, histamine, and methylxanthines, rapidly increase the number of available slow Ca2+--Na+ channels, thus allowing slowly rising electrical responses resembling the plateau component of the cardiac action potential. In embryonic chick (16-20-day-old) myocardial cells (ventricular) studied as intact perfused hearts or as reaggregated cell cultures of trypsin-dispersed cells, high concentrations (10-(3) M) of all of the above drugs blocked the induced slow responses with their associated contractions; low concentrations (10-(5) M) of these agents reduced the maximal rate of rise (+Vmax) of the slow responses and depressed the contractions. For comparison with their effects on the slow response, the actions of these drugs on the normal action potential were also studied. As with the slow response, all of these drugs depressed the rate of rise of the action potential (10-(4) M) or blocked it at higher concentrations (10-(3) M); in contrast, low concentrations (10-(5) M) of lidocaine and DPH increased +V max. These findings suggest that local anesthetics, which interact with the lipid phase of the cell membrane, lead to blockade of the slow Ca2+--Na+ channels as well as of the fast Na+ channels in the myocardial sarcolemma.  相似文献   
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