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91.
目的:探讨小切口入路锁定钢板治疗老年肱骨近端骨折的疗效。方法:选取了80例肱骨近端骨折患者,按随机数字表法分为两组,对照组(39例)给予三角肌入路锁定钢板,观察组(41例)给予小切口入路锁定钢板治疗,通过观察并记录围手术期指标,术前术后3个月的Neer评分,术后24 h的凝血指标,随访3个月期间的并发症发生情况,评价小切口入路锁定钢板治疗老年肱骨近端骨折的疗效。结果:观察组手术、住院、骨折愈合所需时间均短于对照组(P0.05),两组术中出血量相比,无统计学差异(P.05),术前观察组与对照组Neer评分相比,无统计学差异(P0.05),术后3个月,观察组与对照组Neer评分均明显增加,且观察组高于对照组(P0.05)。术前两组凝血指标无明显差异,术后24 h,两组国际标准化比率(International Normalized Ratio,INR)相比无明显变化,血浆凝血酶原时间(prothrombin time,PT),活化部分凝血活酶时间(activated partial thromboplastin time,APTT)均明显降低(P0.05)。对照组血浆纤维蛋白原(Plasma fibrinogen,FIB)水平明显升高,观察组FIB术前术后24 h无明显变化(P0.05),术后24 h,两组患者PT,APTT,INR相比无统计学差异(P0.05)观察组FIB水平明显低于对照组(P0.05)。随访3个月期间,两组均未出现切口感染、血管神经损伤等严重并发症。结论:小切口入路锁定钢板对老年肱骨骨折具有较好的治疗效果,能显著改善患者肩关节功能,对血液系统影响较小,术后并发症少,值得临床推广使用。  相似文献   
92.
We describe a rapid and efficient scheme for the isolation and purification of recombinant baculoviruses. The method is based on the detection of foreign proteins in cellular lysates of baculovirus-infected insect cells by antibody screening. The recombinant virus is purified by repeated serial dilutions. The method allows the identification and purification of recombinant viruses within 2 to 3 wk. This procedure selects for recombinant baculoviruses that highly overproduce the desired protein product.  相似文献   
93.
Scanning electron microscopy (SEM) of tracheary elements of roots of five species from four genera of Marattiaceae and of the rhizome of one species revealed vessel elements present in all. The secondary wall framework of perforation plates is the same as that of lateral wall pitting for vessel elements in all species. Thus, no specialization is present in perforation plates of Marattiaceae compared to the simplified morphology of perforation plates of some leptosporangiate ferns (e.g., Dryopteridaceae, Polypodiaceae, and Pteridaceae). The difference between lateral wall pitting and perforation plates in tracheary elements of Marattiaceae cannot be seen by light microscopy (in which pit membranes are transparent), but is evident with SEM. Diversity in structure of perforation plates (especially the alternation of wide and narrow perforations within a plate) and presence of web-like pit membrane remnants are evident. Vessels are widespread in both leptosporangiate and eusporangiate ferns, although specialization in perforation plates (e.g., bars few and more widely spaced in lateral wall pitting of a given vessel element) is to be expected only in ferns of habitats with marked fluctuation in water availability. Vessels of Marattiaceae lack such specializations and are thus are correlated with the mesic habitats characteristic for the family.  相似文献   
94.
Gas-liquid mass transfer properties of shaken 96-well microtiter plates were characterized using a recently described method. The maximum oxygen transfer capacity (OTR(max)), the specific mass transfer area (a), and the mass transfer coefficient (k(L)) in a single well were determined at different shaking intensities (different shaking frequencies and shaking diameters at constant filling volume) and different filling volumes by means of sulfite oxidation as a chemical model system. The shape (round and square cross-sections) and the size (up to 2 mL maximum filling volume) of a microtiter plate well were also considered as influencing parameters. To get an indication of the hydrodynamic behavior of the liquid phase in a well, images were taken during shaking and the liquid height derived as a characteristic parameter. The investigations revealed that the OTR(max) is predominantly dependent on the specific mass transfer area (a) for the considered conditions in round-shaped wells. The mass transfer coefficient (k(L)) in round-shaped wells remains at a nearly constant value of about 0.2 m/h for all shaking intensities, thus within the range reported in the literature for surface-aerated bioreactors. The OTR(max) in round-shaped wells is strongly influenced by the interfacial tension, determined by the surface tension of the medium used and the surface properties of the well material. Up to a specific shaking intensity the liquid surface in the wells remains horizontal and no liquid movement can be observed. This critical shaking intensity must be exceeded to overcome the surface tension and, thus, to increase the liquid height and enlarge the specific mass transfer area. This behavior is solely specific to microtiter plates and has not yet been observed for larger shaking bioreactors such as shaking flasks. In square-shaped microtiter plate wells the corners act as baffles and cause a significant increase of OTR(max), a, and k(L). An OTR(max) of up to 0.15 mol/L/h can be reached in square-shaped wells.  相似文献   
95.
Perforation plates are reported in aerial and subaerial axes of Psilotum nudum and in aerial axes of Tmesipteris obliqua. In Psilotum, both perforations lacking pit membranes and perforations with pit membrane remnants were observed. Perforation plates in Psilotum may consist wholly of one type or the other. In Tmespteris, perforations have threadlike pit membranes or consist of porose pit membranes. Wide perforations alternating with narrow pits, a conformation observed in various ferns, were observed in Psilotum (subaerial axes). In Psilotum, perforations are more common in metaxylem than in protoxylem; perforations in protoxylem consist of primary wall areas containing small circular porosities or relatively large circular to oval perforations. There are no modifications in the secondary wall framework of protoxylem or metaxylem in Psilotum or Tmesipteris that would permit one to distinguish presence of perforations or perforation plates with light microscopy, and scanning electron microscopy (SEM) is required for demonstration of porose walls or perforations. The tracheary elements of the Psilotaceae studied have no features not also observed in other ferns with SEM.  相似文献   
96.
A solid agar plate assay was devised to discriminate bacteriolytic from bacteriostatic activity for a given antibacterial agent. The assay uses a bacterial culture harboring β-galactosidase enzyme as reporter of cellular lysis. When a drop of bacteriolytic compound is placed on the agar, β-galactosidase is released from the bacteria to the external solid medium where it hydrolyzes X-Gal substrate analogue, developing a blue halo at the edge of the inhibition growth zone. The assay was successfully evaluated against several antibiotics with well-known mechanism of action. It was found that bacteriostatic compounds consistently did not display blue halo at the inhibition zone.  相似文献   
97.
Wood anatomy was examined in 16 species of Meryta (a genus of c . 35 species) and bark anatomy was studied in 12 species. All but two of these taxa form an assemblage corresponding to the Northern Arc clade, one of two major groups identified by a recent molecular phylogenetic study. M. sinclairii and M. tenuifolia (corresponding to the New Zealand/Fiji clade) differ distinctly by having more numerous simple perforation plates, multiseriate rays with few marginal rows, and the absence of sclerified cells in collapsed secondary phloem, a bark feature that has not yet been found elsewhere in Araliaceae. The increase in abundance of simple perforation plates in the wood of these two species is not accompanied by a decrease in the number of bars on scalariform perforation plates. The wood structure of Meryta bears a strong resemblance to members of the Pacific Schefflera clade, sharing similar ranges of variation of several features. Bark characters, such as the diameter of the cortical secretory canals, the types of crystal in cortical cells, the types of axial parenchyma cell in collapsed secondary phloem, and the presence of sheath cells by phloem rays, appear to be of diagnostic value for some species of Meryta .  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 363–379.  相似文献   
98.
目的:探讨胫前减张切口结合锁定加压钢板(LCP)内固定治疗老年胫腓骨远端骨折的临床效果。方法:选择2014年3月-2015年3月本院收治的老年胫腓骨远端骨折患者100例,根据手术方式不同分为减张组和内固定组。减张组行胫前减张切口结合锁定加压钢板内固定术,内固定组行锁定加压钢板内固定术。观察并比较两组患者的手术时间、术中出血量、住院时间、骨折愈合时间、并发症的发生率以及AOFAS评分。结果:两组手术时间、术中出血量及住院时间比较,差异无统计学意义(P0.05);减张组患者骨折愈合时间短于内固定组,并发症的发生率低于内固定组,差异具有统计学意义(P0.05);两组患者AOFAS评分比较,差异无统计学意义(P0.05)。减张组患者的手术优良率高于内固定组,差异具有统计学意义(P0.05)。结论:胫前减张切口结合LCP内固定治疗老年胫腓骨远端骨折的临床效果显著,值得推广应用。  相似文献   
99.
目的:研究胫骨远端锁定加压钢板(LCP)内固定与解剖型钢板内固定术治疗Pilon骨折的临床疗效,为其治疗提供临床依据。方法:选择2010年1月~2014年12月本院收治的Pilon骨折患者共90例,按照随机数字表法随机分为LCP组(采用胫骨远端LCP内固定治疗)和对照组(采用解剖型钢板内固定治疗),比较两组患者手术时间、术中出血量、骨折愈合时间和术后疗效。结果:LCP组患者手术时间、术中出血量和术后愈合时间均小于对照组,差异有统计学意义(P0.05);LCP组患者术后疗效总优良率为89.6%高于对照组的76.2%,差异有统计学意义(P0.05)。结论:胫骨远端LCP内固定治疗Pilon骨折,具有创伤小、手术时间和术后愈合时间短、术中出血量少、术后疗效总优良率高的优点,是治疗Pilon骨折的有效方法  相似文献   
100.
A total of 177 naturally contaminated water samples were analyzed by membrane filtration according to the Standard Methods for the Examination of Water and Wastewater published by the American Public Health Association. Filters were incubated in parallel on mHPC-agar and 3M™ Petrifilm™ Aerobic Count Plates (Petrifilm™ AC plates) for heterotrophic counts. Fecal coliforms and Escherichia coli were enumerated on mFC-agar and 3M™ Petrifilm™ E. coli/Coliform Count Plates (Petrifilm™ EC plates). Typical colonies on each media type were confirmed following standard procedures. Heterotrophic counts were between 103 and 104 CFU/mL and the average log10 counts obtained on Petrifilm™ AC plates were about two-fold lower than on mHPC-agar. Counts for fecal coliforms and E. coli were between 102 and 103 CFU/mL. Average log10 counts for confirmed fecal coliforms obtained on Petrifilm™ EC plates were slightly lower than on mFC agar with a correlation coefficient of 0.949. The average log10 counts for confirmed E. coli on Petrifilm™ EC plates and on mFC agar were statistically not different (P=0.126) with a correlation coefficient of 0.879. Specificity of Petrifilm™ EC plates and mFC agar was evaluated by comparing typical colony counts with confirmed counts. On mFC agar, counts for typical colonies were by 2 log10 CFU higher than the actual confirmed counts. In contrast, on Petrifilm™ EC plates typical colony counts were almost identical to confirmed colony counts for both fecal coliforms and E. coli. This comparison illustrates the high specificity of Petrifilm™ EC plates for enumeration of both fecal coliforms and E. coli in water.  相似文献   
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