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1.
中西医结合医院单病种的质量管理及其作用   总被引:1,自引:0,他引:1  
针对中西医结合医院单病种质量评定没有现成的、规范的标准的现状,就中西医结合单病种的质量管理方法及其在中西医结合医院建设中的作用进行了论述。  相似文献   
2.
Two azobenzene dyes, [Cu(azobenzene-4,4′-dicarboxylate) diethylenediamine]n (ADD), [Cd(4,4′-diazenediyldibenzoato)(H2O)]n (DDB), have been designed, synthesized, and characterized as efficient co-sensitizers for dye-sensitized solar cells (DSSC). The optical, charge-transfer, electrochemical and photovoltaic properties of ADD and DDB are investigated by UV-visible spectroscopy, transient surface photovoltage measurement, cyclic voltammetry, and photocurrent–photovoltage measurement. The combination of ADD and DDB in DSSC leads to a wide spectral absorption over the whole visible range (350–700 nm). DSSC with ADD and DDB exhibits a short-circuit photocurrent density as high as 16.96 mA cm−2, open-circuit photovoltage of 0.73 V, a fill factor of 0.57, and overall light conversion efficiency of 7.1% under standard global AM1.5 solar irradiation conditions.

The combination of two azobenzene dyes leads to a wide spectral absorption and overall light conversion efficiency of 7.1%.  相似文献   
3.
Herein, an urchin-like Sb2S3 nanostructure has been synthesized without a surfactant via a wet chemical method. The crystal structure, morphology, composition and optical properties were characterized using XRD, TEM, SEM, EDS, Raman spectroscopy, and diffuse reflectance absorption spectroscopy. The factors, including the reaction time, temperature, and ratio of the raw materials, influencing the evolution of the urchin-like morphology have been discussed, and a plausible formation mechanism for the urchin-like Sb2S3 has been proposed. The urchin-like Sb2S3 micro/nanostructure exhibits high catalytic performance towards the degradation of MB under visible light irradiation. The photodegradation ratio of MB is up to 99.32% under visible light irradiation of 130 min. Our synthesis method will be extended to prepare other photocatalysts.

Urchin-like Sb2S3 has been successfully synthesized without a surfactant using a wet chemical method. The as-prepared unique nanostructure provides a high specific surface area, leading to superior catalytic performance under visible light irradiation.

In recent years, nanomaterials with controllable size and novel morphologies have been extensively studied due to their unique physical and chemical properties.1–5 For instance, AgBr nanoplates,6 AgCl octahedrons7 and NaTi2(PO4)3 nanocubes8 show unique photocatalytic activities and electrochemical performances. Hierarchical flower-like SnO2 nanospheres9 or TiO2 nanorod arrays10,43 exhibit highly efficient gas sensing and photoelectrochemical properties.As an important V–VI compound, antimony sulfide (Sb2S3) is considered as a promising material for energy conversion due to its suitable band gap (1.5–2.2 eV), which covers the range of the solar spectrum.11–13 To the best of our knowledge, Sb2S3 nanomaterials with different morphologies have been mainly synthesized using various surfactants.14 Surfactants can regulate the morphology and structure of the nanoparticles effectively by parceling on the surface of the particles through the coordination or charge effect.15 By adding surfactants such as cetyltrimethylammonium bromide (CTAB),16 polyethylene glycol (PEG),17 dodecyltrimethylammonium bromide (DTAB)18 and polyvinylpyrrolidone (PVP),19–21 some nanostructures including straw-tied-like, nanorod22,23, nanosheet,24 nanotube, dandelion-like, double cauliflower-like,25 bar,26 dumbbell-like, and nanowire bundle structures have been successfully prepared, which show potential applications in photocatalysis and energy storage areas. However, how to effectively synthesize Sb2S3 crystals and control their morphology via a simple method is still challenging for materials scientists. Herein, we report a simple wet chemical method to synthesize an urchin-like Sb2S3 nanostructure without any surfactant. Moreover, we have examined the photocatalytic activity of Sb2S3 by the degradation of MB under simulated visible light irradiation. Our study presents an Sb2S3 nanostructure with good application in the visible-light photocatalytic field.The morphology and size of the products were revealed by the SEM and TEM images. Fig. 1a shows the SEM image of the urchins-like Sb2S3 prepared under refluxing conditions at 160 °C for 5 h. The as-prepared Sb2S3 products mainly consist of the uniform urchin-like structure. The magnified SEM image shows that the urchin-like structure consists of nanorods stretching radially from the same central point (Fig. 1b). The TEM image further confirms that the urchin-like Sb2S3 is made up of many individual nanorods with lengths about 10 μm and diameters of 100 nm (Fig. 1b and c). The measured spacing of the crystallographic planes is 0.309 nm, which is consistent with the (320) plane lattice distance of orthorhombic Sb2S3 (Fig. 1d).Open in a separate windowFig. 1(a) SEM, (b and c) TEM and (d) HRTEM images, (e) XRD pattern and (f) EDS spectrum of urchin-like Sb2S3.The XRD pattern of the obtained sample is shown in Fig. 1e. All the diffraction peaks in the XRD pattern can be readily indexed to orthorhombic Sb2S3 (JCPDS no. 42-1393) with the calculated lattice parameters of a = 1.120 nm, b = 1.128 nm and c = 0.383 nm. No characteristic peaks for impurities are observed. The fact that the reflection peaks of Sb2S3 are strong and sharp indicates that Sb2S3 is highly crystalline (Fig. 1e). The EDS spectrum reveals that the as-prepared products consist of S and Sb elements, and the observed C and Cu peaks are due to the carbon-coated Cu grid27 (Fig. 1f). Furthermore, the elemental distribution ratio of S and Sb in the compound was found to be about 3 : 2 through the quantification calculation of the EDS peaks, which was consistent with the chemical formula of antimony sulfide.28The effects of the reaction time, reaction temperature and the ratio of the raw materials on the as-obtained products were carefully studied to investigate the formation of the urchin-like morphology. Fig. 2 reveals the SEM images of the as-obtained samples prepared at different reaction times. Initially, no product was formed. When the reaction time was prolonged to 2 h, amorphous antimony sulfide was formed (Fig. 2a). After 3 h, single units with slight splitting were observed (Fig. 2b). Upon increasing the reaction time, uniform urchin-like Sb2S3 was obtained. When the reaction time was further increased to 6 h, the urchin-like structure was transformed into a rod-flower structure in which the thorns of the urchin-like structure were thicker (Fig. 2c). As shown in Fig. 2d and e, after 9 h, the rod-flower structure began to rupture and finally converted into irregular nanorods with lengths of about 15 μm, as shown in Fig. 2f.Open in a separate windowFig. 2SEM images of the Sb2S3 prepared at 160 °C for different times: (a) 2 h, (b) 3 h, (c) 6 h, (d) 9 h, (e) 12 h, and (f) 15 h.The reaction temperature also has a significant effect on the morphologies of the final products. As shown in Fig. 3a, amorphous nanoparticles with an irregular shape were formed at 140 °C. When the temperature was increased to 150 °C, a simple splitting phenomenon appeared. Upon further increasing the temperature, the urchin-like micro/nanostructure was formed. A further increase in the reaction temperature led to the formation of rod flowers. When the reaction temperature was 180 °C, some rod-like structures appeared.Open in a separate windowFig. 3SEM images of Sb2S3 prepared for 5 h at different reaction temperatures: (a) 140 °C, (b) 150 °C, (c) 170 °C and (d) 180 °C.We examined the effect of the ratio of the raw materials on the product. Only rod particles were observed at a ratio of S/Sb = 1 : 1 (Fig. 4a). When the ratio was increased to 1 : 3, the urchin shapes were observed. A further increase in the concentration of the sulfur source led to the appearance of nest structures. Irregular spherical particles were finally generated when the ratio of the raw materials was 1 : 7.Open in a separate windowFig. 4SEM images of Sb2S3 prepared with different ratios of S and Sb: (a) S/Sb = 1 : 1, (b) S/Sb = 1 : 3, (c) S/Sb = 1 : 5, and (d) S/Sb = 1 : 7.Based on the experimental results, a plausible reaction for the synthesis of the Sb2S3 crystals can be interpreted as follows:CH3CSNH2 + 2OH → S2− + CH3COO + NH4+1[Sb2(C4H4O6)2]2− → 2Sb3+ + 2(C4H4O6)4−22Sb3+ + 3S2− → Sb2S3↓3According to the abovementioned experimental results, we speculated the formation mechanism of the urchin-like Sb2S3 structure. Sb2S3 is a highly anisotropic semiconducting material with infinite ribbon-like (Sb4S6) polymers and layers in its orthorhombic crystal structure.29,30 As already reported in the literature, Sb2S3 tends to easily form one-dimensional nanorods along the c-axis due to intermolecular attraction between the antimony and sulfur atoms.31–34 Because of the fast and anisotropic crystal growth, many newborn clusters agglomerate together to deposit on a particular particle face, causing crystal splitting when the solution is in the excess saturation state.35,36 Then, each of the nanorods starts to grow into urchin-like crystals. This is similar to the chain-like crystalline structure of Bi2S3; this further ascertains that Sb2S3 has a strong splitting ability.37,38 Our research suggests that the degree of splitting is increased when the reaction time is prolonged. In the subsequent stage, the nanorods are detached from the urchin-like structures; this results in well-dispersed nanorods due to the instability of the surface energy.39 The whole process of this morphological evolution is shown schematically in Fig. 5. The amorphous nanoparticles of Sb2S3 appeared with no splitting. Upon increasing the reaction time, the Sb2S3 nanostructures change from small sheaves with simple splitting to urchin-like structures.Open in a separate windowFig. 5A schematic of the formation of the urchin-like Sb2S3 structure.The fact that the optical properties of the as-prepared Sb2S3 are determined using the absorption spectrum (Fig. 6a) provides a simple and effective method to estimate the band gap of the urchin-like Sb2S3.40,41 The band gap value of 1.64 eV determined by other researchers is quite comparable to the values reported in the bibliographical information.42 Furthermore, it can be seen that optical absorption occurs in nearly all the visible light region; this suggests that the as-synthesized Sb2S3 can be stimulated by visible light. Raman spectrum of the urchin-like Sb2S3 is shown in Fig. 6b. The appearance of sharp peaks at 147, 198, 257, 305, and 452 cm−1 suggests the formation of a highly crystalline product, which is consistent with the XRD results.43 Due to suitable band gap of urchin-like Sb2S3, the photocatalytic activity of urchin-like Sb2S3 was assessed by depositing an organic dye (MB) in an aqueous solution under visible light irradiation. The concentration of MB dye was monitored at 665 nm using an UV/vis spectrophotometer. From the blank experiment (Fig. S2), we can see a slight drop in the curve due to self-degradation of MB dye under visible light irradiation. Therefore, we can conclude that the dye is almost photo-stable under these conditions. It can be clearly observed from Fig. 6c that the organic dye is slightly degraded by Sb2S3 in the dark. According to Fig. 6d, the organic dye could be degraded by only 23.1% using H2O2, whereas the degradation efficiency for MB dye was 99.34% in the presence of Sb2S3 and H2O2 after 130 min; this indicated that the degradation of the organic dye was mainly attributed to the excellent photocatalytic activity of Sb2S3. The photoluminescence spectra of the as-prepared urchin-like Sb2S3 shows a low signal, suggesting the good charge separation properties of our samples (Fig. S1a). Fig. S1b shows the IT curves of the FTO/Sb2S3 photoelectrode, of which the photocurrent intensity is 36.057 μA cm−2 at a potential of 0 V versus Ag/AgCl, and this fast photocurrent response is consistent with the PL results. Fig. 6e shows the photocatalytic degradation of an aqueous solution of MB at different concentrations by urchin-like Sb2S3. However, with an increase in the concentration of MB, the degradation efficiency is reduced. Furthermore, the cycling performance of urchin-like Sb2S3 was measured using the same photodegradation process. The photocatalyst was obtained by centrifugation and washed with deionized water after each cycle. The degradation ratio decreased slightly after reuse for 5 times; the slight decay in the photodegradation activity was partially ascribed to the inevitable loss of the photocatalyst during the washing and centrifugation process; this suggested that Sb2S3 exhibited prominent photocatalytic stability (Fig. 6f).Open in a separate windowFig. 6(a) The diffuse reflectance absorption spectrum of the as-prepared Sb2S3 sample (the inset presents the corresponding plots of (αhυ)2versus photon energy). (b) The room-temperature Raman spectrum. (c) The degradation curve for MB in the dark. (d) The degradation curves for MB using the different catalyst systems (e) the degradation curves at different MB concentrations. (f) The cycling runs for the degradation of MB.The promising photocatalytic activity of Sb2S3 can be mainly attributed to its relatively narrow band gap (1.64 eV), making it a perfect photocatalyst to efficiently absorb and utilize visible-light energy. As is known, the urchin-like nanostructure has been extensively investigated due to its potential applications in many areas such as in varistors, electronic devices, UV-absorbers, and catalysis.47,48 This kind of nanostructure has a high specific surface area, which endows it with a large contact area with the dye and superior light harvesting efficiency in the field of photocatalysis.49 Moreover, the single crystalline nanorod-assembled urchin-like nanostructure is favorable for fast electron transfer and thus facilitates electron and hole separation.46,50,51 In particular, when urchin-like Sb2S3 is irradiated by visible light of energy greater than its band gap, electron–hole pairs will be generated and partially separated. The electrons and holes react with the adsorbed surface substances, such as O2 and OH, to form the reactive species ·O2−, ·OH, which are the major oxidative species in the decomposition of organic pollutants. Then, the oxidative species degrade the organic pollutant into small molecules such as CO2 and H2O.44,45p-Benzoquinone (BQ) and isopropyl alcohol (IPA) were used as additive agents to trap the active species ·O2 and ·OH, respectively. Fig. S2 shows the degradation curves for MB after the addition of the different capture agents. It can be seen that IPA has a significant inhibitory effect on the degradation of MB, whereas the effect of BQ is less; this indicates that ·OH plays a major role in the photocatalytic process.The degradation of the organic dye was accomplished via a series of parallel and consecutive redox reactions as show in eqn (2.1)–(2.5).Sb2S3 + → Sb2S3 (h+VB + eCB)2.1O2 + eCB → ·O22.2H2O → H+ + OH2.3OH + h+VB → ·OH2.4MB + ·OH + ·O2− → CO2 + H2O + …2.5In summary, an urchin-like Sb2S3 nanostructure was successfully prepared without surfactants using a wet chemical method. The corresponding crystal splitting formation mechanism of urchin-like Sb2S3 was tentatively suggested. The narrow band gap of the urchin-like Sb2S3 was evaluated to be 1.64 eV, which was close to the best photoelectric conversion value reported to date. In addition, urchin-like Sb2S3 exhibited excellent photocatalytic performance; the degradation efficiency for the organic dye was 99.34% after exposure to visible-light irradiation for 130 min. The high photocatalytic activity of Sb2S3 was mostly due to its narrow band gap and wide absorption range of visible light. Our investigation demonstrates that Sb2S3 with urchin-like nanostructures has great potential to be applied in the degradation of organic contaminants.  相似文献   
4.
[背景]观察苦碟子注射液治疗心绞痛的临床疗效.[病例报告]将120例心绞痛患者分为2个组,给予治疗组患者苦碟子注射液静脉滴注,对照组患者给予丹参注射液,疗程为15d,观察两组患者临床症状、心电图表现及血液流变学变化情况,治疗组各项指标均明显优于对照组.[讨论]苦碟子注射液是治疗心绞痛的有效药物.  相似文献   
5.
孙方纬 《中国热带医学》2008,8(8):1385-1386
目的探讨奥扎格雷钠治疗进展型脑梗死疗效及安全性。方法在神经科常规治疗的基础上加用奥扎格雷钠治疗60例,并设相应的对照组。治疗前后做血液流变学指标及血脂测定。结果总有效率治疗组91.7%,对照组86.7%。显效率治疗组68.3%,对照组45.0%。两组比较差异有显著性(P〈0.01)。实验室指标也有相应变化。结论奥扎格雷钠是治疗进展型脑梗死安全有效的方法。  相似文献   
6.
张志宏  陈定法  刘菲 《吉林医学》2010,(35):6431-6433
目的:对没有神经症状的胸腰椎爆裂性骨折手术和非手术治疗的疗效进行比较,探讨治疗方法的选择。方法:复习从2002年1月~2006年1月共收治不伴有神经症状的胸腰椎爆裂性骨折病例98例,其中非手术治疗47例,手术治疗51例。对骨折遗留后凸畸形、矫正后椎体高度丢失、腰部疼痛改善和患者功能恢复进行分析及统计学处理。结果:平均随访2.2年,随访结果发现,手术组患者局部或者整体后凸畸形及椎体高度丢失情况明显较保守治疗组轻;而保守治疗组腰部疼痛改善及功能评分明显较手术组理想,但差异没有统计学意义(P>0.05)。结论:对没有神经症状的胸腰椎爆裂性骨折,与非手术治疗相比,手术治疗在长期疗效方面并没有优势。保守治疗似乎应该是最优先的选择,只有当这种选择失效时再进行手术治疗。  相似文献   
7.
我国卫生部于2009年1月颁发了《医务人员手卫生规范》,手卫生是预防和控制医院感染最简单、最方便、最有效的方法,为医务人员洗手、手卫生消毒和外科手消毒的总称。目前,中西医结合医院在日常诊疗过程中.医务人员手卫生现状令人担忧。为降低隐患,加强医务人员的手卫生的工作预防和控制医院感染,本文笔者从本院中西医结合角度出发,在中医操作过程中,通过对医务人员手卫生依从性的现状分析,提出了改进措施,并取得了一定的成效。  相似文献   
8.
任杰  张威  赵洪伟  任天赋 《吉林医学》2009,30(5):419-420
目的:探讨应用AO锁骨钩钢板(CHP)治疗锁骨远端骨折伴肩锁关节脱位的实用价值。方法:对1999年8月-2007年4月收治的锁骨远端骨折伴肩锁关节脱位28例,均采用AO锁骨钩钢板(CHP)内固定治疗,对其临床资料进行回顾性分析。结果:全部骨性愈合,随访8~48个月,平均23个月。无钢板断裂、螺钉松动、感染及再脱位,无骨折不愈合病例,肩关节功能均恢复良好。CHP取出时间8—17个月,平均11个月。结论:CHP对锁骨远端骨折并肩锁关节脱位治疗效果理想,骨折不愈合可以避免,并且可以早期功能练习,使骨折愈合与功能恢复同步进行,而且具有操作简单、易掌握、损伤小、疗效确切的特点,值得临床应用推广,是目前有效治疗此种损伤的最佳方法。  相似文献   
9.
目的:比较内固定和人工关节置换在高龄不稳定性股骨转子间骨折治疗中的疗效。方法:75岁以上患者97例,分别采用内固定(DHS、DCS、PFN)和人工关节置换术治疗,对其术后半年、1年和3年疗效分别进行比较。结果:术后半年、1年人工关节置换组疗效优于内固定组,术后3年两组疗效无显著性差异。结论:人工关节置换术对于高龄股骨转子间骨折的治疗,尤其是存在严重骨质疏松、骨折粉碎难以内固定者,具有一定优势。  相似文献   
10.
魏本立  张敏 《中国民康医学》2011,23(10):1186-1187
目的:研究中药远志改善学习记忆障碍的药理作用。方法:观察远志煎剂对东莨菪碱所致记忆获得障碍模型小鼠学习记忆功能的影响和远志煎剂对亚硝酸钠所致记忆巩固障碍模型小鼠记忆功能的影响。结果:远志煎剂中、高剂量组对东莨菪碱所致记忆获得障碍小鼠在学习和记忆中实验潜伏期较模型组延长,错误次数减少,差异有统计学意义(P<0.05,P<0.01)。亚硝酸钠所致记忆巩固障碍模型小鼠远志煎剂中、高剂量组较模型组潜伏期延长,错误次数减少,差异有统计学意义(P<0.05~0.01)。结论:远志煎剂可以改善东莨菪碱所致记忆获得障碍模型小鼠学习记忆功能,也能改善记忆巩固障碍模型小鼠的记忆能力。  相似文献   
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