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71.
The ventral arc of the pubis is frequently used for sexing adult human hip bones. This study addresses the issues of the anatomical and developmental bases for the ventral arc. Dissection of seven adult pelves (four females and three males) demonstrates that the sexes are identical in the muscular and ligamentous attachments to this ridge of bone. The tendons of gracilis and adductor brevis, which are fused for a variable extent, arise from the ridge of bone, and the fibers of the ventral pubic ligament attach to its medial border. Lateral placement of the ventral arc is defined in terms of the minimum distance between the ridge of bone and the inferior border of the symphyseal face of the pubis. The hypothesis that lateral placement of the ventral arc is positively correlated with pubic length was tested using two random samples of adult female hip bones (N = 50 for both whites and blacks) from the Hamann-Todd collection. The correlation between these variables is significant. The results support the argument that lateral placement of the ventral arc is related to the amount of postadolescent growth occurring at the symphyseal border of the pubis. Therefore, the ventral arc should not be considered as an independent criterion from pubic length in sexing adult hip bones.  相似文献   
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The M2 protein from influenza A virus is a 97-amino-acid protein with a single transmembrane helix that forms proton-selective channels essential to virus function. The hydrophobic transmembrane domain of the M2 protein (M2TM) contains a sequence motif that mediates the formation of functional tetramers in membrane environments. A variety of structural models have previously been proposed which differ in the degree of helix tilt, with proposed tilts ranging from approximately 15 degrees to 38 degrees . An important issue for understanding the structure of M2TM is the role of peptide-lipid interactions in the stabilization of the lipid bilayer bound tetramer. Here, we labeled the N terminus of M2TM with a nitroxide and studied the tetramer reconstituted into lipid bilayers of different thicknesses using EPR spectroscopy. Analyses of spectral changes provide evidence that the lipid bilayer does influence the conformation. The structural plasticity displayed by M2TM in response to membrane composition may be indicative of functional requirements for conformational change. The various structural models for M2TM proposed to date--each defined by a different set of criteria and in a different environment--might provide snapshots of the distinct conformational states sampled by the protein.  相似文献   
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Dienogest (DNG) administration is a well-established treatment for endometriosis but bleeding irregularities remain its main disadvantage. Changes in diet, mainly to vegetable consumption, are beneficial in the treatment of estrogen-related pathologies but their use for endometriosis has been poorly studied. In this study, addition of the phytochemical 3,3′-diindolylmethane (DIM) to DNG therapy has been investigated in in vitro and ex vivo models for endometriosis and in a small cohort of women with endometriosis. Endometrial Ishikawa cells were treated with DNG or DIM at dosages from 10?10?M to 10?5?M for up to 72?h. Cell proliferation was measured by assessing BrdU incorporation. Endometrial tissue from women with endometriosis and controls was incubated with DNG or a combination of DNG and DIM. Tissue viability was determined using a modified colorimetric MTS assay. 17β-estradiol secretion was quantified by an electro-chemiluminescence immunoassay. Finally, DNG as monotherapy or in combination with DIM was randomly administered to women with endometriosis (n?=?8) over 3 months. Bleeding patterns and associated pelvic pain were assessed by Visual Analogue Scale (VAS). DNG and DIM significantly reduced cell proliferation in Ishikawa cells. Ex vivo, DIM reduced viability and estradiol secretion specifically in endometriotic but not in normal endometrial tissue. This effect was enhanced by combination with DNG. Endometriosis associated pelvic pain was significantly reduced in patients taking the DNG-DIM combination therapy compared to those taking DNG alone. Bleeding pattern (number and duration of episodes) was significantly improved by addition of DIM to the DNG treatment. In conclusion, addition of DIM enhances effects of DNG ex vivo and may ameliorate bleeding patterns in endometriosis patients.  相似文献   
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目的:分析因症状性盆腔器官脱垂(POP)接受手术治疗患者的临床资料,探讨不同手术方式的疗效及临床应用。方法:选择2010年7月至2014年12月在青岛大学附属医院因POP接受手术治疗的176例患者为研究对象,其中全盆底重建术97例,阴道骶骨固定术22例,传统手术(经阴子宫切除+阴道壁修补术)57例。回顾性分析不同术式患者的临床资料、手术疗效及病人生活质量评分及性生活影响等相关资料。结果:1三组手术患者在手术时间、出血量及住院费用上均存在不同的差别。其中盆底重建组手术时间及出血量明显低于传统手术组及骶骨固定组(P=0.00)。2176例患者中有163例患者完成术后12个月随访。其中传统手术组患者的客观治愈率低于其他两组患者,差异有统计学意义(P0.05)。3三种术式术后6、12个月PFDI-20评分均较术前下降,且差异有统计学意义(P0.05),三组间术前及术后6个月PFDI-20评分比较无差异;术后12个月传统手术组评分高于其他两组,差异有统计学意义(P0.05)。4在术后恢复性生活的患者当中,盆底重建组及传统组中有患者出现不同程度的性交痛,而骶骨固定组其性生活较前术前明显改善,三组间差异有统计学意义(P0.05)。三组患者术后新发尿失禁的比率无统计学意义。结论:三种术式各具优缺点,但均为症状性POP的有效治疗方式。在临床应用中,要综合评估患者的年龄、合并症、性生活要求及经济情况等,制定和选择最合理的个体化方案。  相似文献   
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坐标旋转对东北山地森林涡动通量的影响   总被引:2,自引:2,他引:0  
王兴昌  王传宽 《生态学杂志》2016,27(9):2779-2788
坐标旋转是复杂地形条件下涡动协方差(EC)通量观测的必要步骤,系统评价不同坐标旋转方法的影响有助于提高EC通量观测的精度.以处于山谷坡面的帽儿山温带落叶阔叶林为例,采用标准主轴法探讨了复杂地形条件下不同倾斜校正方法对感热通量(H)、潜热通量(LE)、CO2通量(Fc)、能量平衡、摩擦风速(u*)和垂直速度(w)的影响.结果表明: 与校正前的通量相比,二次旋转(DR)、平面拟合(PF)、垂直速度无偏平面拟合(NBPF)、月尺度平面拟合(MPF)、三次旋转(TR)和月尺度分风向区平面拟合(MSWPF)得到的H变幅依次为+1.5%、+3.8%、+3.1%、+3.3%、-1.3%和-7.1%.对LE来说,NBPF和DR分别升高1.0%和0.4%,PF增加0.671 W·m-2,MPF降低0.4%,但截距增加0.747 W·m-2,MSWPF和TR则分别降低4.5%和15.1%.坐标旋转后Fc降幅为6.0%(DR)~12.1%(TR).不同倾斜校正方法中,PF使能量平衡闭合平均提高约2%,TR却降低约6%.从校正后的u*w看,TR和NBPF不宜用于风速仪倾斜校正.考虑到EC观测精度和应用,帽儿山站坐标系统应优先选择PF,其次为DR.此结果为复杂地形条件下EC通量观测的风速仪倾斜校正提供参考.  相似文献   
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Given the substantial literature on the use of Monte Carlo (MC) simulations to verify treatment planning system (TPS) calculations of radiotherapy dose in heterogeneous regions, such as head and neck and lung, this study investigated the potential value of running MC simulations of radiotherapy treatments of nominally homogeneous pelvic anatomy. A pre-existing in-house MC job submission and analysis system, built around BEAMnrc and DOSXYZnrc, was used to evaluate the dosimetric accuracy of a sample of 12 pelvic volumetric arc therapy (VMAT) treatments, planned using the Varian Eclipse TPS, where dose was calculated with both the Analytical Anisotropic Algorithm (AAA) and the Acuros (AXB) algorithm. In-house TADA (Treatment And Dose Assessor) software was used to evaluate treatment plan complexity, in terms of the small aperture score (SAS), modulation index (MI) and a novel exposed leaf score (ELS/ELA). Results showed that the TPS generally achieved closer agreement with the MC dose distribution when treatments were planned for smaller (single-organ) targets rather than larger targets that included nodes or metastases. Analysis of these MC results with reference to the complexity metrics indicated that while AXB was useful for reducing dosimetric uncertainties associated with density heterogeneity, the residual TPS dose calculation uncertainties resulted from treatment plan complexity and TPS model simplicity. The results of this study demonstrate the value of using MC methods to recalculate and check the dose calculations provided by commercial radiotherapy TPSs, even when the treated anatomy is assumed to be comparatively homogeneous, such as in the pelvic region.  相似文献   
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Protein association in lipid membranes is a complex process with thermodynamics directed by a multitude of different factors. Amino-acid sequence is a molecular parameter that affects dimerization as shown by limited directed mutations along the transmembrane domains. Membrane-mediated interactions are also important although details of such contributions remain largely unclear. In this study, we probe directly the free energy of association of Glycophorin A by means of extensive parallel Monte Carlo simulations with recently developed methods and a model that accounts for sequence-specificity while representing lipid membranes faithfully. We find that lipid-induced interactions are significant both at short and intermediate separations. The ability of molecules to tilt in a specific hydrophobic environment extends their accessible interfaces, leading to intermittent contacts during protein recognition. The dimer with the lowest free energy is largely determined by the favorable lipid-induced attractive interactions at the closest distance. Finally, the coarse-grained model employed herein, together with the extensive sampling performed, provides estimates of the free energy of association that are in excellent agreement with existing data.  相似文献   
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