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41.
目的:通过检测STMN1及UBE2C基因在胃癌组织中的表达,探索其表达与临床病理因素间的关联及两基因表达间的关联。方法:采用免疫组化的方法检测180例胃癌病理标本及对应180例正常胃部黏膜标本中STMN1及UBE2C基因的表达情况。结果:STMN1在胃癌组织中的阳性表达率为85.6%,而在正常组织中阳性表达率为26.1%(P<0.05),STMN1的表达与患者性别、年龄及肿瘤分化程度无明显相关性,而与TNM分期、淋巴结转移及Lauren分型明显相关(P<0.05)。UBE2C在胃癌组织中的阳性表达率为73.3%,而在正常组织中阳性表达仅为24.4%(P<0.05),UBE2C的表达与患者性别、年龄及肿瘤分化程度均无显著相关,而与淋巴结转移、TNM分期及Lauren分型关联性显著(P<0.05)。Logistic多因素分析表明,淋巴结转移、Lauren分型、TNM分期与STMN1及UBE2C表达相关(P<0.05)。STMN1与UBE2C基因表达呈正相关(r=0.288,P<0.05)。结论:STMN1的表达与胃癌的产生、进展、浸润及转移密切相关,UBE2C可能通过PI3K/Akt信号通道调节STMN1。 相似文献
42.
国产PJ-I型电脑型人体平衡功能检测仪的应用 总被引:12,自引:1,他引:12
目的:客观、定量了解正常及多种疾病患者的静立平衡功能;检验国际上常用指标及新增指标的敏感性。方法:运用国产电脑型人体平衡功能检测仪对504例正常人及246例神经科、五官科、骨伤科患者进行检测,分析比较其静态姿势图。结果:该仪器大部分指标与年龄呈曲线关系,脑卒中、共济失调、颈椎病及非颈椎肱眩晖患者静立明显下降,帕金森病在0.01 ̄0.1Hz摆相对功率增加。四肢骨骼疾病患者静立稳定性较小。结论:该仪器 相似文献
43.
经鼻胃管与鼻空肠管营养在重症急性胰腺炎中应用的Meta分析 总被引:2,自引:0,他引:2
目的分析鼻胃管与鼻空肠管两种肠内营养方式在重症急性胰腺炎中的疗效。方法检索外文数据库PubMed、Wiley、Elseviser、Springer Link及中文数据库中国期刊全文数据库(CNKI)、中国科技期刊数据库(VIP)、万方数字化期刊全文数据库中关于鼻胃管与鼻空肠管两种肠内营养方式比较治疗重症急性胰腺炎的随机对照试验,由两个评价员对文献进行评价,意见不统一时通过讨论解决或由第三者判断。采用RevMan5.3软件对纳入研究进行Meta分析。结果共有6项随机对照试验纳入本研究,共纳入研究对象326例,其中NGEN组166例,NJEN组160例。分析结果显示:NGEN组在病死率(OR=0.82,95%CI0.40~1.68,P=0.59)、营养相关性腹泻(OR=1.36,95%CI0.57~3.24,P=0.49)、营养相关性腹痛(OR=1.43,95%CI0.64~3.21,P=0.39)、手术干预率(OR=2.03,95%CI0.48~8.57,P=0.34)、置管脱出率(OR=0.39,95%CI0.07~2.29,P=0.30)、胰腺坏死(OR=0.87,95%CI0.45~1.68,P=0.68)等方面与NJEN组差异无统计学意义;而感染性并发症(OR=0.46,95%CI0.24~0.88,P=0.02)鼻胃管组显著低于鼻空肠管组。结论鼻胃管给予营养可以达到与鼻空肠管相似的疗效,且操作方便,费用低廉,在感染性并发症发生率方面优于后者,具有代替鼻空肠管的可能性。 相似文献
44.
Xinge Yu Jeremy Smith Nanjia Zhou Li Zeng Peijun Guo Yu Xia Ana Alvarez Stefano Aghion Hui Lin Junsheng Yu Robert P. H. Chang Michael J. Bedzyk Rafael Ferragut Tobin J. Marks Antonio Facchetti 《Proceedings of the National Academy of Sciences of the United States of America》2015,112(11):3217-3222
Metal-oxide (MO) semiconductors have emerged as enabling materials for next generation thin-film electronics owing to their high carrier mobilities, even in the amorphous state, large-area uniformity, low cost, and optical transparency, which are applicable to flat-panel displays, flexible circuitry, and photovoltaic cells. Impressive progress in solution-processed MO electronics has been achieved using methodologies such as sol gel, deep-UV irradiation, preformed nanostructures, and combustion synthesis. Nevertheless, because of incomplete lattice condensation and film densification, high-quality solution-processed MO films having technologically relevant thicknesses achievable in a single step have yet to be shown. Here, we report a low-temperature, thickness-controlled coating process to create high-performance, solution-processed MO electronics: spray-combustion synthesis (SCS). We also report for the first time, to our knowledge, indium-gallium-zinc-oxide (IGZO) transistors having densification, nanoporosity, electron mobility, trap densities, bias stability, and film transport approaching those of sputtered films and compatible with conventional fabrication (FAB) operations.Metal-oxide (MO) semiconductors, especially in amorphous phases, represent an appealing materials family for next generation electronics owing to their high carrier mobilities, good environmental/thermal stability, mechanical flexibility, and excellent optical transparency (1–3). MO films complement organic semiconductors (4, 5), carbon/oxide nanomaterials (6), and flexible silicon (7, 8) for enabling new technologies, such as flexible displays and printed sensors. For fabricating high-performance electronics with acceptable fidelity, conventional processes require capital-intensive physical/chemical vapor deposition techniques. Capitalizing on the solubility of MO precursors in common solvents, solution methods have been used to fabricate semiconducting MO layers for thin-film transistors (TFTs). However, the fabrication process and field-effect mobilities of these TFTs are not competitive with the corresponding vapor-deposited (e.g., sputtered) devices (9), and developing routes to solution-derived MO TFTs with technologically relevant thicknesses and performance comparable to state of the art vapor-deposited devices is a critical milestone for MO electronics evolution.Sol-gel techniques are used extensively for MO film growth, including films for high-performance TFTs (10–13). However, the required sol-gel condensation, densification, and impurity removal steps typically require >400–500 °C processing temperatures, which are incompatible with inexpensive glasses and typical flexible plastic substrates (14). Progress toward significantly reducing the processing temperatures of sol gel-derived MO films has afforded excellent TFT mobilities; however, achieving both reproducible high-performance and stable device operation remains an unsolved issue for Ga-containing materials (15). Sol-gel on-a-chip for indium-zinc-oxide (3) and deep-UV irradiation of spin-coated MO precursor films (1) represent significant advances; however, challenges remain. Recently, this laboratory reported a low-temperature solution method, spin-coating combustion synthesis (spin-CS), for fabricating MO TFTs (SI Appendix, Fig. S1) (2, 16). By incorporating an oxidizer and a fuel in the precursor solution, localized, highly exothermic chemical transformations occur within the spin-coated films, effecting rapid condensation and M-O-M lattice formation at temperatures as low as 200–300 °C, which was assessed by thermal and X-ray diffraction (XRD) analysis, and yielding high-performance TFTs. Additional work has subsequently broadened the spin-CS fuel/oxidizer options and accessible MO compositions (17).Note, however, that independent of the particular solution processing method, significant quantities of gaseous H2O, N2, NOx, CO2, etc. are evolved, compromising film continuity and densification in single-step, thick-film growth processes (17–21). These issues also apply to combustion synthesis, especially because the exotherm is of short duration. Therefore, films must be sufficiently thin (typically <10–20 nm for conventional sol gel and <5–10 nm for combustion) to yield high-quality films (2, 3, 15). For MO TFT implementation in, for example, active-matrix display backplanes, semiconductor thicknesses must be 50–100 nm to avoid back-channel effects, delayed turn-on, and bias stress shifting (22, 23). Thus, for current generation MO TFT structures, suitable film thicknesses from conventional solution processes require inefficient multiple deposition and anneal sequences, which are time-consuming, and invariably create bulk trap states at the semiconductor interfaces.In contrast to spin coating, spray processes are readily adapted to continuous large-area, high-throughput coating as in roll-to-roll processing. Simple spray coating has been used to fabricate organic solar cells (24), organic TFTs (25), and MO electronics (26) using heated substrates. In pioneering work, spray-coated sol-gel ZnO TFTs achieved mobilities of ∼0.1 cm2 V−1 s−1 for 200 °C growth and ∼25 cm2 V−1 s−1 for 500 °C growth (26). These results raise the intriguing question of whether combustion processing can be combined with spray coating to realize, at low temperatures, dense high-mobility MO films having significant, precisely controlled thicknesses in a single step and specifically, growing the most technologically relevant oxide film materials: semiconducting indium-gallium-tin oxide (IGZO) and conducting indium-tin-oxide (ITO).Here, we report a low-temperature, nanometer-thickness, controlled solution route to high-performance MO electronics through spray-combustion synthesis (SCS). Reduced gaseous byproduct trapping yields dense, high-quality, macroscopically continuous films of both crystalline and amorphous MOs. Single-layer (50-nm-thick) IGZO TFTs with carrier mobilities 102–104× greater (7–20 cm2/Vs) than those achieved with sol gel and conventional combustion synthesis are demonstrated and rival those of magnetron-sputtered IGZO TFTs. Film characterization includes the first positron annihilation spectroscopy (PAS) measurements on oxide thin films to our knowledge, X-ray photoelectron spectroscopy (XPS), X-ray reflectivity (XRR), and capacitance-voltage (C-V) data, supporting the broad applicability of SCS. 相似文献
45.
Manman Lu Guangjin Hou Huilan Zhang Christopher L. Suiter Jinwoo Ahn In-Ja L. Byeon Juan R. Perilla Christopher J. Langmead Ivan Hung Peter L. Gor'kov Zhehong Gan William Brey Christopher Aiken Peijun Zhang Klaus Schulten Angela M. Gronenborn Tatyana Polenova 《Proceedings of the National Academy of Sciences of the United States of America》2015,112(47):14617-14622
Host factor protein Cyclophilin A (CypA) regulates HIV-1 viral infectivity through direct interactions with the viral capsid, by an unknown mechanism. CypA can either promote or inhibit viral infection, depending on host cell type and HIV-1 capsid (CA) protein sequence. We have examined the role of conformational dynamics on the nanosecond to millisecond timescale in HIV-1 CA assemblies in the escape from CypA dependence, by magic-angle spinning (MAS) NMR and molecular dynamics (MD). Through the analysis of backbone 1H-15N and 1H-13C dipolar tensors and peak intensities from 3D MAS NMR spectra of wild-type and the A92E and G94D CypA escape mutants, we demonstrate that assembled CA is dynamic, particularly in loop regions. The CypA loop in assembled wild-type CA from two strains exhibits unprecedented mobility on the nanosecond to microsecond timescales, and the experimental NMR dipolar order parameters are in quantitative agreement with those calculated from MD trajectories. Remarkably, the CypA loop dynamics of wild-type CA HXB2 assembly is significantly attenuated upon CypA binding, and the dynamics profiles of the A92E and G94D CypA escape mutants closely resemble that of wild-type CA assembly in complex with CypA. These results suggest that CypA loop dynamics is a determining factor in HIV-1''s escape from CypA dependence.Cyclophilin A (CypA), a peptidyl-prolyl isomerase, is a host factor critical in the regulation of the HIV-1 infection, involving a direct interaction with the capsid (CA) protein (1–3). The mechanism by which CypA modulates the viral infectivity is complex and poorly understood, being dependent on the CA protein primary sequence and the host cell type (4–6). For example, it is known that mutations in the CypA-binding loop of the CA protein dramatically reduce virus infectivity (7, 8). The A92E and G94D escape mutants bind CypA with similar affinity to wild-type CA, but exhibit only 10% of the activity of wild-type CA in the presence of CypA, and full infectivity can be restored if CypA is inhibited with cyclosporin A in the host cells (8), as shown schematically in SI Appendix, Fig. S1. Alas, the molecular mechanisms underlying CypA escape remain elusive, despite numerous virological, biochemical, and structural–biological studies.The present study investigates the internal conformational dynamics of a CA protein assembly. Although static structures of HIV-1 proteins and complexes with host factors provide important clues into their assembly architecture and conformational details of the interactions, structures alone are insufficient for understanding molecular mechanisms. It is well known that biological functions can be dynamically regulated, at multiple levels of organization, from internal dynamics of individual protein molecules (9) to entire cells. This dynamic regulation certainly also applies to HIV-1 because numerous dynamic processes are associated with HIV-1 assembly, disassembly, release, and maturation (10, 11). For example, we previously demonstrated that internal conformational dynamics of the CA protein and its structural plasticity determine its ability to assemble into pleiomorphic conical capsids (12, 13) (Fig. 1). We also uncovered that, in the HIV-1 CA-SP1 maturation intermediate, dynamic disorder in the SP1 peptide plays an important role in the final step of virus maturation, permitting condensation of CA into the cores of infectious virions (14).Open in a separate windowFig. 1.(A, Left) All-atom MD-derived model of mature HIV-1 capsid constructed on the basis of cryo-electron tomography (cryo-ET) and solution NMR studies (13). The capsid comprises 216 hexamers (orange) and 12 pentamers (blue) [Protein Data Bank (PDB) ID 3J3Y]. Structural organization of a hexamer of hexamers (HOH) building block is illustrated in the expansion. Color coded are individual hexameric units comprising the HOH building block. (A, Right) The 3D structure of CA monomer [HXB2 sequence polymorph [PDB file 3NTE (42)]. (B) Cosedimentation assay of CA with CypA illustrating the efficiency of cosedimentation for different CA/CypA molar ratios. S, supernatant; P, pellet. (C) Transmission electron microscopy (TEM) images of tubular assemblies of CA and CA/CypA. (C, Upper) CA NL4-3 (Left), CA NL4-3 A92E (Center), and CA NL4-3 G94D (Right). (C, Lower) HXB2 (Left) and CA HXB2/CypA (Right). (D) Expansions around the aliphatic region for 2D NCA and combined R2-driven (CORD) MAS NMR spectra for CA HXB2 (black) and CA HXB2/CypA (orange), illustrating the multiple chemical shift perturbations observed upon formation of the complex. These perturbations are mapped onto the structure of CA monomer (A) and are confined to flexible loops and residue variation sites. The spectra are recorded at 20.0 T and the MAS frequency of 14 kHz. (E) Expansions of glycine regions for 2D NCA MAS NMR spectra for (from left to right): HXB2, HXB2/CypA, NL4-3, NL4-3 A92E, and NL4-3 G94D. Dashed lines indicate the G89 cross-peaks associated with cis- and trans-P90.In this study, we examined the residue-specific mobility of CA protein from HXB2 and NL4-3 sequence polymorphs (SI Appendix, Fig. S2) in tubular assemblies on the nanoseconds to milliseconds timescales. In particular, we compared wild-type and A92E and G94D escape mutants of the NL4-3 strain as well as wild-type HXB2 CA alone and in complex with CypA. As discussed previously (14, 15), tubular assemblies recapitulate the hexameric lattice, the predominant symmetry arrangement of the conical HIV-1 capsid core, illustrated in Fig. 1A. Dipolar tensors and resonance intensities extracted from a series of 2D and 3D homonuclear and heteronuclear magic-angle spinning (MAS) NMR experiments revealed that certain regions in both HXB2 and NL4-3 wild-type CA are unusually dynamic on all timescales. These motions are significantly attenuated upon CypA binding. Most remarkably, the dynamic profiles of the A92E and G94D escape mutants closely resemble that of CA when bound by CypA. To gain further understanding of the sequence-dependent dynamics profiles of CA assemblies, we performed extensive molecular dynamics (MD) simulations. The motionally averaged dipolar tensors extracted from the MD trajectories are in remarkable quantitative agreement with the NMR results. Together, our results suggest that changes in the sequence-dependent conformational dynamics may be a key determinant in the escape mechanism of HIV-1 CA capsid mutants from CypA dependence. 相似文献
46.
目的:评价针刺蝶腭神经节治疗中重度持续性变应性鼻炎的临床疗效。方法本研究为非随机对照研究。将符合纳入标准的患者按就诊顺序以1∶1比例分为2组,每组25例。针刺蝶腭神经节组采用毫针刺激蝶腭神经节,1~2次/周;常规针刺组采用传统针刺方法,以迎香、印堂、风池、风府、足三里等为主穴,以上星、合谷、禾髎、肺俞、脾俞、肾俞、三阴交等为配穴,每次取主穴、配穴各1~2穴,2次/周。2组均连续治疗4周。采用鼻炎症状总分量表(2004版)、鼻炎症状总分量表(total nasal symptom score, TNSS)、鼻炎伴随症状总分量表(total non-nasal symptom score, TNNSS)评价症状改善情况;采用鼻结膜炎生活质量量表(rhinoconjunctivitis quality of life questionnaire, RQLQ)评价生活质量;比较2组患者针刺起效时间、疗效持续时间,以及治疗后1个月复发天数。结果针刺蝶腭神经节组治疗后鼻炎症状总分[(99.74±31.89)分比(196.83±31.22),t=-4.912]、TNSS[(165.18±51.06)分比(209.37±53.31)分,t=-4.032]、TNNSS[(33.63±12.37)分比(71.82±19.21),t=-3.463]均明显低于常规针刺组(P 均<0.05)。与常规针刺组比较,针刺蝶腭神经节组针刺后症状改善起效时间[(13.85±4.21)min 比(45.63±7.87)min;t=-1.763,P=0.008]更短,而疗效持续时间[(37.92±9.94)h 比(3.35±1.23)h;t=7.637,P<0.01]更长。针刺蝶腭神经节组治疗后4周RQLQ评分[(8.48±3.71)分比(37.68±12.46)分,F=-7.312]低于常规针刺组(P<0.01)。治疗后1个月针刺蝶腭神经节组复发天数[(4.12±2.15)d 比(23.53±4.63)d,t=-8.879]明显少于常规针刺组(P<0.01)。结论针刺蝶腭神经节治疗中重度持续性变应性鼻炎优于传统针刺方法。 相似文献
47.
目的 探讨陪护人员管理的方法。方法 采用生活满意度指数(LSR-A)量表及自制陪护人员陪护能力问卷调查,对45名陪护人员采用管理干预措施,采用前后对照的方法。结果 ①干预前大部分被调查人员生活满意度水平处于低水平(≤13的有41人,占有效调查者91.1% ),仅4人(8.9%)生活满意度处于中等水平。干预后生活满意度得到提高(≥14的有27人,占有效调查者60%),P<0.05。②陪护人员陪护能力情况:由于方便抽样,抽取的陪护人员均为熟手,因此干预前的陪护能力较高,分数为26.67±2.59(满分30分);干预后分数为28.89±1.17,P<0.05,干预后的陪护能力得到提高。结论 从管理上加强对陪护人员的支持能有效的提高其生活满意度,提高其陪护能力,进而提高对患者照顾的质量。 相似文献
48.
目的 观察短程三联疗法对功能性消化不良 (FD)Helicobacterpylori感染的根除效果。方法 73例H .pylori阳性的FD患者被随机分为A、B 2个治疗组 ,A组 (n =3 6) :奥美拉唑 2 0mgbid ,阿莫西林 1 0bid ,甲硝唑 0 4bid ,疗程 1周 ;B组 (n =3 7) :雷尼替丁 0 15bid ,阿莫西林 1 0bid ,甲硝唑 0 4bid ,疗程 1周 ;疗程结束时记录每组病人症状缓解情况 ,疗程结束后 1个月复查H .py lori。结果 H .pylori根除率分别为A组 5 2 8% (19/ 3 6)、B组 43 2 % (16/ 3 7) ,两组比较无统计学差异 (P >0 0 5 ) ,疗程结束时症状缓解率分别为A组 66 7% (2 4/ 3 6) ,B组 5 1 3 % (19/ 3 7) ,无统计学差异 (P >0 0 5 )。结论 本实验短程三联疗法对FD的H .pylori根除率及症状缓解率过低 ,不适合用于FD的H .pylori根治治疗 相似文献
49.
肿块型胰腺炎的CT诊断 总被引:4,自引:0,他引:4
目的:探讨肿块型胰腺炎的CT征象特征。方法:回顾性分析经病理证实的25例肿块型胰腺炎的CT资料,采用PQ5000V螺旋CT,平扫及增强,层厚及层距均为10mm。结果:25例中23例肿块位于胰头部,2例位于胰体部。16例肿块密度均匀,增强一致。5例可见钙化;胰管扩张15例,14例轻度,10例不规则扩张,6例穿过肿块;12例合并胆总管炎,5例胆总管内可见结石;肝外胆管扩张18例,15例轻度,12例下端逐渐变细;肾前筋膜增厚10例;胰前脂肪层模糊6例。结论:肿块型胰腺炎具有较可靠的CT征象,CT能对大多数的肿块型胰腺炎作出较准确诊断。 相似文献
50.
目的探讨经直肠常规超声在前列腺结节定性诊断中的应用价值。方法对临床怀疑前列腺疾病患者行经直肠二维超声、彩色多普勒超声及能量多普勒超声检查,检出前列腺实性结节患者43例共55个结节,分析良恶性结节超声图像特征,并将结果与病理结果对照。结果55个实性结节病理证实33个恶性(恶性组)、22个良性(良性组)。恶性组与良性组比较,良恶性结节在发生部位上差异有统计学意义(P〈0.05);而良恶性结节声像图在形态、边界、内部回声及血流分级上差异均无统计学意义(P〉0.05)。经直肠超声诊断前列腺癌的灵敏度、特异度、诊断准确度分别为60.6%、54.5%、58.2%。结论经直肠常规超声图像清晰,对前列腺结节分辨力高,在发现结节和定位诊断方面具有重要的临床应用价值,但前列腺良恶性结节声像图存在交叉重叠,经直肠超声对前列腺结节良恶性的鉴别价值有限。 相似文献