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11.
Qian Cui Eric J. Vanman Dongtao Wei Wenjing Yang Lei Jia Qinglin Zhang 《Social cognitive and affective neuroscience》2014,9(10):1472-1480
The ability of a deceiver to track a victim’s ongoing judgments about the truthfulness of the deceit can be critical for successful deception. However, no study has yet investigated the neural circuits underlying receiving a judgment about one’s lie. To explore this issue, we used a modified Guilty Knowledge Test in a mock murder situation to simultaneously record the neural responses involved in producing deception and later when judgments of that deception were made. Producing deception recruited the bilateral inferior parietal lobules (IPLs), right ventral lateral prefrontal (VLPF) areas and right striatum, among which the activation of the right VLPF contributed mostly to diagnosing the identities of the participants, correctly diagnosing 81.25% of ‘murderers’ and 81.25% of ‘innocents’. Moreover, the participant’s response when their deception was successful uniquely recruited the right middle frontal gyrus, bilateral IPLs, bilateral orbitofrontal cortices, bilateral middle temporal gyrus and left cerebellum, among which the right IPL contributed mostly to diagnosing participants’ identities, correctly diagnosing 93.75% of murderers and 87.5% of innocents. This study shows that neural activity associated with being a successful liar (or not) is a feasible indicator for detecting lies and may be more valid than neural activity associated with producing deception. 相似文献
12.
Yuanshan Cui Huantao Zong Chenchen Yang Huilei Yan Yong Zhang 《International urology and nephrology》2014,46(1):275-284
Purpose
Mirabegron, a potent and selective β3-adrenoceptor agonist, has been developed for the treatment of overactive bladder (OAB). We carried out a systematic review and meta-analysis to assess the efficacy and safety of the drug for treating OAB.Methods
A literature review was performed to identify all published randomized double-blind, placebo-controlled phase III trials of mirabegron for the treatment of OAB. The search included the following databases: MEDLINE, EMBASE and the Cochrane Controlled Trials Register. The reference lists of the retrieved studies were also investigated. A systematic review and meta-analysis of phase III trials were conducted.Results
Four publications involving a total of 5,761 patients were used in the analysis, including four phase III RCTs that compared mirabegron with placebo. We found that mirabegron was effective in treating OAB in our meta-analysis. Co-primary efficacy end points: the mean number of incontinence episodes per 24 h (the standardized mean difference (SMD) = ?0.44, 95 % confidence interval (CI) ?0.59 to ?0.29, p < 0.00001); the mean number of micturitions per 24 h (SMD = ?0.62, 95 % CI ?0.80 to ?0.45, p < 0.00001) and key secondary efficacy end points: mean volume voided per micturition; mean number of urgency episodes per 24 h indicated that mirabegron was more effective than the placebo. Safety assessments included common treatment-emergent adverse events (TEAEs) [OR 1.10, 95 % CI 0.93–1.31, p = 0.25), hypertension, cardiac arrhythmia TEAEs, urinary retention and discontinuations due to adverse event indicated that mirabegron was well tolerated.Conclusions
This meta-analysis indicates that mirabegron to be an effective and safe treatment for OAB symptoms with a low occurrence of side effects. It offers promise as an effective oral agent for the treatment of OAB with a distinct efficacy/tolerability balance. 相似文献13.
Bairen Zhu Hualing Zeng Junfeng Dai Zhirui Gong Xiaodong Cui 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(32):11606-11611
We report the observation of anomalously robust valley polarization and valley coherence in bilayer WS2. The polarization of the photoluminescence from bilayer WS2 follows that of the excitation source with both circular and linear polarization, and remains even at room temperature. The near-unity circular polarization of the luminescence reveals the coupling of spin, layer, and valley degree of freedom in bilayer system, and the linearly polarized photoluminescence manifests quantum coherence between the two inequivalent band extrema in momentum space, namely, the valley quantum coherence in atomically thin bilayer WS2. This observation provides insight into quantum manipulation in atomically thin semiconductors.Tungsten sulfide WS2, part of the family of group VI transition metal dichalcogenides (TMDCs), is a layered compound with buckled hexagonal lattice. As WS2 thins to atomically thin layers, WS2 films undergo a transition from indirect gap in bulk form to direct gap at monolayer level with the band edge located at energy-degenerate valleys (K, K′) at the corners of the Brillouin zone (1–3). Like the case of its sister compound, monolayer MoS2, the valley degree of freedom of monolayer WS2 could be presumably addressed through nonzero but contrasting Berry curvatures and orbital magnetic moments that arise from the lack of spatial inversion symmetry at monolayers (3, 4). The valley polarization could be realized by the control of the polarization of optical field through valley-selective interband optical selection rules at K and K′ valleys as illustrated in Fig. 1A (4–6). In monolayer WS2, both the top of the valence bands and the bottom of the conduction bands are constructed primarily by the d orbits of tungsten atoms, which are remarkably shaped by spin–orbit coupling (SOC). The giant spin–orbit coupling splits the valence bands around the K (K′) valley by 0.4 eV, and the conduction band is nearly spin degenerated (7). As a result of time-reversal symmetry, the spin splitting has opposite signs at the K and K′ valleys. Namely, the Kramer’s doublet |K ↑ ? and |K′ ↓ ? is separated from the other doublet |K′ ↑ ? and |K ↓ ? by the SOC splitting of 0.4 eV. The spin and valley are strongly coupled at K (K′) valleys, and this coupling significantly suppresses spin and valley relaxations as both spin and valley indices have to be changed simultaneously.Open in a separate windowFig. 1.(A) Schematic of valley-dependent optical selection rules and the Zeeman-like spin splitting in the valence bands of monolayer WS2. (B) Diagram of spin–layer–valley coupling in 2H stacked bilayer WS2. Interlayer hopping is suppressed in bilayer WS2 owing to the coupling of spin, valley, and layer degrees of freedom.In addition to the spin and valley degrees of freedom, in bilayer WS2 there exists an extra index: layer polarization that indicates the carriers’ location, either up-layer or down-layer. Bilayer WS2 follows the Bernal packing order and the spatial inversion symmetry is recovered: each layer is 180° in plane rotation of the other with the tungsten atoms of a given layer sitting exactly on top of the S atoms of the other layer. The layer rotation symmetry switches K and K′ valleys, but leaves the spin unchanged, which results in a sign change for the spin–valley coupling from layer to layer (Fig. 1B). From the simple spatial symmetry point of view, one might expect that the valley-dependent physics fades at bilayers owing to inversion symmetry, as the precedent of bilayer MoS2 (8). Nevertheless, the inversion symmetry becomes subtle if the coupling of spin, valley, and layer indices is taken into account. Note that the spin–valley coupling strength in WS2 is around 0.4 eV (the counterpart in MoS2 ∼ 0.16 eV), which is significantly higher than the interlayer hopping energy (∼0.1 eV); the interlayer coupling at K and K′ valleys in WS2 is greatly suppressed as indicated in Fig. 1B (7, 9). Consequently, bilayer WS2 can be regarded as decoupled layers and it may inherit the valley physics demonstrated in monolayer TMDCs. In addition, the interplay of spin, valley, and layer degrees of freedom opens an unprecedented channel toward manipulations of quantum states.Here we report a systemic study of the polarization-resolved photoluminescence (PL) experiments on bilayer WS2. The polarization of PL inherits that of excitations up to room temperature, no matter whether it is circularly or linearly polarized. The experiments demonstrate the valley polarization and valley coherence in bilayer WS2 as a result of the coupling of spin, valley, and layer degrees of freedom. Surprisingly, the valley polarization and valley coherence in bilayer WS2 are anomalously robust compared with monolayer WS2.For comparison, we first perform polarization-resolved photoluminescence measurements on monolayer WS2. Fig. 2A shows the photoluminescence spectrum from monolayer WS2 at 10 K. The PL is dominated by the emission from band-edge excitons, so-called “A” exciton at K and K′ valleys. The excitons carry a clear circular dichroism under near-resonant excitation (2.088 eV) with circular polarization as a result of valley-selective optical selection rules, where the left-handed (right handed) polarization corresponds to the interband optical transition at K (K′) valley. The PL follows the helicity of the circularly polarized excitation optical field. To characterize the polarization of the luminescence spectra, we define a degree of circular polarization as , where I(σ±) is the intensity of the right- (left-) handed circular-polarization component. The luminescence spectra display a contrasting polarization for excitation with opposite helicities: P = 0.4 under σ+ excitation and P = −0.4 under σ− excitation on the most representative monolayer. For simplicity, only the PL under σ+ excitation is shown. The degree of circular polarization P is insensitive to PL energy throughout the whole luminescence as shown in Fig. 2A, Inset. These behaviors are fully expected in the mechanism of valley-selective optical selection rules (3, 4). The degree of circular polarization decays with increasing temperature and drops to 10% at room temperature (Fig. 2B). It decreases as the excitation energy shifts from the near-resonance energy of 2.088 to 2.331 eV as illustrated in Fig. 2C. The peak position of A exciton emission at band edges shifts from 2.04 eV at 10 K to 1.98 eV at room temperature. The energy difference between the PL peak and the near-resonance excitation (2.088 eV) is around 100 meV at room temperature, which is much smaller than the value 290 meV for the low temperature off-resonance excitation at 2.331 eV. However, the observed polarization for off-resonance excitation at 10 K (P = 16%) is much higher than the near-resonance condition at room temperature (P = 10%). It clearly shows that the depolarization cannot be attributed to single process, namely the off-resonance excitation or band-edge phonon scattering only (10).Open in a separate windowFig. 2.Photoluminescence of monolayer WS2 under circularly polarized excitation. (A) Polarization resolved luminescence spectra with σ+ detection (red) and σ− detection (black) under near-resonant σ+ excitation (2.088 eV) at 10 K. Peak A is the excitonic transition at band edges of K (K′) valleys. Opposite helicity of PL is observed under σ− excitation. Inset presents the degree of the circular polarization at the prominent PL peak. (B) The degree of the circular polarization as a function of temperature. The curve (red) is a fit following a Boltzmann distribution where the intervalley scattering by phonons is assumed. (C) Photoluminescence spectrum under off-resonant σ+ excitation (2.33 eV) at 10 K. The red (black) curve denotes the PL circular components of σ+ (σ−).Next we study the PL from bilayer WS2. Fig. 3 shows the PL spectrum from bilayer WS2. The peak labeled as “I” denotes the interband optical transition from the indirect band gap, and the peak A corresponds to the exciton emission from direct band transition at K and K′ valleys. Although bilayer WS2 has an indirect gap, the direct interband optical transition at K and K′ valleys dominates the integrated PL intensity as the prerequisite of phonon/defect scattering is waived for direct band emission and the direct gap is just slightly larger than the indirect band gap in bilayers. Fig. 3A displays surprisingly robust PL circular dichroism of A exciton emission under circularly polarized excitations of 2.088 eV (resonance) and 2.331 eV (off resonance). The degree of circular polarization of A exciton emission under near-resonant σ± excitation is near unity (around 95%) at 10 K and preserves around 60% at room temperature. In contrast, the emission originating from indirect band gap is unpolarized in all experimental conditions.Open in a separate windowFig. 3.Photoluminescence of bilayer WS2 under circularly polarized excitations. (A) Polarization-resolved luminescence spectra with components of σ+ (red) and σ− (black) under near-resonant σ+ excitation (2.088 eV) at 10 K. Peak A is recognized as the excitonic transition at band edge of direct gap. Peak I originates from the indirect band-gap emission, showing no polarization. Inset presents the circular polarization of the A excitonic transition around the PL peak. Opposite helicity of PL is observed under σ− excitation. (B) The degree of circular polarization as a function of temperature (black). The curve (red) is a fit following a Boltzman distribution where the intervalley scattering by phonons is assumed. (C) Photoluminescence spectrum of components of σ+ (red) and σ− (black) under off-resonance σ+ excitation (2.33 eV) at 10 K. A nonzero circular polarization P is only observed at emissions from A excitons.To exclude the potential cause of charge trapping or substrate charging effect, we study the polarization-resolved PL of bilayer WS2 with an out-plane electric field. Fig. 4A shows the evolution of PL spectra in a field-effect-transistor-like device under circularly polarized excitations of 2.088 eV and an electric gate at 10 K. The PL spectra dominated by A exciton show negligible change under the gate bias in the range of −40 to 20 V. The electric-conductance measurements show that the bilayer WS2 stays at the electrically intrinsic state under the above bias range. The PL spectra can be safely recognized as emissions from free excitons. As the gate bias switches further to the positive side (>20 V), the PL intensity decreases, and the emission from electron-bounded exciton “X−,” the so-called trion emerges and gradually raises its weight in the PL spectrum (11, 12). The electron–exciton binding energy is found to be 45 meV. Given only one trion peak in PL spectra, the interlayer trion (formed by exciton and electron/hole in different layers) and intralayer trion (exciton and electron/hole in the same layer) could not be distinguished due to the broad spectral width (13). Both the free exciton and trion show slight red shifts with negative bias, presumably as a result of quantum-confined stark effect (14). At all of the bias conditions, the degree of circular polarization of the free exciton and trion stays unchanged within the experiment sensitivity as shown in Fig. 4C.Open in a separate windowFig. 4.Electric-doping-dependent photoluminescence spectrum of bilayer WS2 field-effect transistor. (A) Luminescence spectra of bilayer WS2 at different gate voltage under near-resonant σ+ excitation (2.088 eV) at 10 K. X and X− denote neutral exciton and trion, respectively. Green curve is a fitting consisting of two Lorentzian peak fits (peak I and X−) and one Gaussian peak fit (peak X). (B) Intensity of exciton and trion emissions versus gate. (Upper) The gate-dependent integral PL intensity consisting of exciton (X) and trion (X−). (Lower) The ratio of the integral PL intensity of exciton versus that of trion, as a function of the gate voltage. (C) Degree of circular polarization of exciton (X, red) and trion (X−, blue) versus the gate.It is also unlikely that the high polarization in bilayers results from the isolation of the top layer from the environments, as similar behaviors are observed in monolayer and bilayer WS2 embedded in polymethyl methaccrylate (PMMA) matrix or capped with a 20-nm-thick SiO2 deposition. The insensitivity of the circular-polarization degree on bias and environments rules out the possibility that the effects of Coulomb screening, charge traps, or charge transfers with substrates are the major causes for the robust circular dichroism in bilayers against monolayers.One potential cause may result from the shorter lifetime of excitons at K (K′) valley for bilayer system. The band gap shifts from K and K′ points of the Brillouin zone in monolayers to the indirect gap between the top of the valence band at Γ points and the bottom of the conduction band in the middle of K and Γ points in bilayers. Combining our time-resolved pump-probe reflectance experiments (Supporting Information) and the observed relative PL strength between monolayer and bilayer (10:1), we infer the exciton lifetime at K (K′) valleys around 10 ps, a fraction of that at monolayers. If we assume (i) the PL circular polarization , where P0 is the theoretical limit of PL polarization, and τk and τ denote the valley lifetime and exciton lifetime respectively; and (ii) the valley lifetime is the same for both monolayers and bilayers, the shorter exciton lifetime will lead to significantly higher PL polarization. However, the difference in exciton lifetime between bilayers and monolayers is not overwhelming enough to be the major cause of robust polarization observed in the time-integrated PL in bilayers.In monolayer WS2 under circularly polarized resonant excitations, the depolarization mainly comes from the K ? K′ intervalley scattering. In bilayers, the depolarization could be either via K ? K′ intervalley scattering within the layer in a similar way as in monolayers, or via interlayer hopping, which also requires spin flip. As we discussed above, the interlayer hopping at K valley is suppressed in WS2 as a result of strong SOC in WS2 and spin–layer–valley coupling, which were experimentally proved by the circular dichroism in PL from bilayers. The robust polarization in bilayers implies that the intervalley scattering within a layer is diminished compared with that in monolayers. There are two prerequisites for intervalley scattering within layers: conservation of crystal momentum and spin flip of holes. The crystal momentum conservation could be satisfied with the involvement of phonons at K points in the Brillouin zone or atomic size defects, presumably sharing the similar strength in monolayers and bilayers. Spin-flip process could be realized by three different spin scattering mechanisms, namely D’yakonov–Perel (DP) mechanism (15), Elliot–Yaffet (EY) mechanism (16), and Bir–Aronov–Pikus (BAP) mechanism (17, 18). The DP mechanism acts through a Lamor precession driven by electron wavevector k dependent spin–orbit coupling. It is thought to be negligible for spin flip along out-plane direction as the mirror symmetry with respect to the plane of W atoms secures a zero out-plane crystal electric field. Another possible driving force behind the DP mechanism could be the asymmetry owing to the interface with the substrate. This can be excluded by the similar behaviors, where the monolayers and bilayers WS2 are embedded in PMMA matrix or capped with a thin layer of SiO2. The negligible effect of electric gating on polarization also implies that the DP mechanism is weak in monolayer and bilayer WS2; the EY mechanism originates from scattering with phonons and defects. Its strength in bilayers and monolayers is likely to be at similar scale, and bilayers even have more low-frequency collective vibrational modes (19). Therefore, EY mechanism is unlikely to be the cause here; the BAP mechanism originates from the electron–hole exchange interaction. In monolayer and bilayer TMDCs, the optical features are dominated by the Wannier type, yet giant excitonic effect, and the exciton-binding energy in such intrinsic 2D semiconductors is estimated to be 0.6 ∼ 1 eV (20, 21). This giant exciton-binding energy indicates a mixture of electron and hole wavefunctions and, consequently, strong exchange interaction, which may contribute to the spin flip and intervalley scattering (5, 22). As the conduction band has a band mixing at K points, the spin flip of the electron would be a quick process. An analogous scenario is that the spin of holes relaxes in hundreds of femtoseconds or fewer in GaAs as a result of band mixing and spin–orbit coupling. The electron spin flip could lead to hole spin flip via strong exchange interaction accompanying intervalley scattering, which is realized by the virtual annihilation of a bright exciton in the K valley and then generation in the K′ valley or vice versa (22). This non-single-particle spin relaxation leads to valley depolarization instead of the decrease of luminescence intensity that results from coupling with dark excitons. Generally, the exciton-binding energy decreases with the relaxation of spatial confinement. However, first principle calculation shows that monolayer and bilayer WS2 share the similar band dispersion and effective masses around K valley in their Brillouin zone as a result of spin–valley coupling (7). It implies that the binding energy of excitons around K valley in bilayer WS2 is similar to or slightly less than that in monolayer WS2. As the exchange interaction is roughly proportional to the square of exciton binding energy, the spin-flip rate and consequently intervalley scattering via exciton exchange interactions is presumably comparable or smaller to some extent in bilayer WS2 (Supporting Information). Nevertheless, this is unlikely the major cause of the anomalously robust valley polarization in bilayer WS2.Another possibility includes extra spin-conserving channels via intermediate intervalley-interlayer scatterings in bilayer WS2, which are absent in monolayers (23). The extra spin-conserving channel may compete with the spin-flip process and reduce the relative weight of spin-flip intervalley scattering to some extent. However, the mechanism and the strength are unclear so far. Overall, the robust circular polarization in bilayers likely results from combined effects of the shorter exciton lifetime, smaller exciton-binding energy, extra spin-conserving channels, and the coupling of spin, layer, and valley degrees of freedom, indicating the relatively weak intervalley scattering in bilayer system. Further quantitative study is necessary to elaborate the mechanism.We also investigated the PL from bilayer WS2 under a linearly polarized excitation. A linearly polarized light could be treated as a coherent superposition of two opposite-helicity circularly polarized lights with a certain phase difference. The phase difference determines the polarization direction. In semiconductors, a photon excites an electron–hole pair with the transfer of energy, momentum, and phase information. The hot carriers energetically relax to the band edge in a quick process around 10−1 ∼ 101 ps through runs of inelastic and elastic scatterings, e.g., by acoustic phonons. During the quick relaxation process, generally the phase information randomizes and herein coherence fades. In monolayer TMDCs, the main channel for carrier relaxation is through intravalley scatterings including Coulomb interactions with electron (hole) and inelastic interactions with phonons, which are valley independent and preserve the relative phase between K and K′ valleys (24). In bilayer WS2, the suppression of intervalley scattering consequently leads to the suppression of inhomogeneous broadening in carrier’s phase term. Subsequently, the valley coherence demonstrated in monolayer WSe2 (24) is expected to be enhanced in bilayers (13). The valley coherence in monolayer and bilayer WS2 could be monitored by the polarization of PL under linearly polarized excitations.Fig. 5A shows the linearly polarized components of PL under a linearly polarized excitation of 2.088 eV at 10 K. The emission from indirect band gap is unpolarized and A exciton displays a pronounced linear polarization following the excitation. The degree of linear polarization is around 80%, where I(∥)(I(⊥)) is the intensity of PL with parallel (perpendicular) polarization with respect to the excitation polarization. In contrast, the linear polarization is much weaker in monolayer samples (4% under the same experimental conditions, as shown in Fig. 5B). As presented in Fig. 5C, the polarization of A exciton is independent of crystal orientation and exactly follows the polarization of excitations. The degree of the linear polarization in bilayer WS2 slightly decreases with the increased temperature and drops from 80% at 10 K to 50% at room temperature (Fig. 5D). This is the paradigm of the robust valley coherency in bilayer WS2.Open in a separate windowFig. 5.Linearly polarized excitations on monolayer and bilayer WS2. (A) Linear-polarization-resolved luminescence spectra of bilayer WS2 under near-resonant linearly polarized excitation (2.088 eV) at 10 K. Red (black) presents the spectrum with parallel (cross) polarization with respect to the linear polarization of excitation source. A linear polarization of 80% is observed for exciton A, and the indirect gap transition (I) is unpolarized. (B) Linear-polarization-resolved luminescence spectra of monolayer WS2 under near-resonant linearly polarized excitation (2.088 eV) at 10 K. Red (black) denotes the spectrum with the parallel (cross) polarization with respect to the linear polarization of excitation source. The linear polarization for exciton A in monolayer WS2 is much weaker, with a maximum value of 4%. (C) Polar plot for intensity of the exciton A in bilayer WS2 (black) as a function of the detection angle at 10 K. Red curve is a fit-following cos2(θ). (D) The degree of linear polarization of exciton A in bilayer WS2 (black) as a function of temperature. The curve (red) is a fit following a Boltzmann distribution where the intervalley scattering by phonons is assumed. (E) Electric doping dependence of the linear polarization of exciton A in bilayer WS2 at 10 K.The linear polarization of both exciton and trion in bilayer, contrasting to the circular polarization, which is insensitive to the electric field in the range, shows a weak electric gating dependence as shown in Fig. 5E. The PL linear polarization, presenting valley coherence, decreases as the Fermi level shifts to the conduction band. It does not directly affect intervalley scattering within individual layers and makes negligible change in circular dichroism. Nevertheless, the electric field between the layers induces a layer polarization and slightly shifts the band alignments between the layers by different amounts in conduction and valence bands (13, 25), although the shift is indistinguishable in the present PL spectra due to the broad spectral width. The layer polarization and the shift of band alignments may induce a relative phase difference between two layers and therefore affect the PL linear polarization via interference. Further study is needed to fully understand the mechanism.In summary, we demonstrated anomalously robust valley polarization and valley polarization coherence in bilayer WS2. The valley polarization and valley coherence in bilayer WS2 are the direct consequences of giant spin–orbit coupling and spin valley coupling in WS2. The depolarization and decoherence processes are greatly suppressed in bilayer, although the mechanism is ambiguous. The robust valley polarization and valley coherence make bilayer WS2 an intriguing platform for spin and valley physics. 相似文献
14.
We retrospectively studied 32 consecutive patients (32 hips) who underwent THA with a Durom large-head, MOM articulation between January 2008 and December 2010. Of the patients who underwent THA using a Trilogy metal on polyethylene prosthesis during the same period, 32 were chosen to form the Trilogy group. 32 volunteers were chosen to form the control group. At the last follow-up, serum metal ion levels, liver and kidney function and host immunologic immune responses were evaluated. The mean Co and Cr levels in the Durom group were 4.33- and 1.95-fold higher than those in the Trilogy group. CD3 +, CD4 + and CD8 + cell levels in the Durom group were significantly decreased. The INF-γ level in the Durom group was significantly higher than that in the Trilogy and control groups. 相似文献
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APACHEⅡ评分在外科ICU感染防治中的应用 总被引:3,自引:1,他引:3
外科 ICU(SICU)是三级甲等医院内重要的抢救单元 ,也是医院内感染的高发病区。急性生理学及慢性健康状况评分 系统 (APACHE )已广泛用于ICU疾病严重程度的评估及预后评价、疾病变化趋势的动态观察、动态评价救治水平、制订和修正医疗护理计划等各领域〔1 ,2〕 ,我们也探讨过其在 SICU中的应用价值〔3〕。现将 APACHE 用于SICU医院内下呼吸道感染发生和防治中的结果总结如下。1 临床资料1.1 病例 :我院 1999年 1月— 2 0 0 2年6月 SICU中 APACHE 评分准确者32 6例 ,其中男 2 5 0例 ,女 76例 ;年龄2~ 82岁 ,平均 (5 3.4 … 相似文献
20.
介绍了空肠营养的适应证、营养管的置入途径、空肠营养的时机、灌注方式、营养品的选择,阐明早期给予空肠营养对危重病人的重要意义及对现存问题的护理干预。 相似文献