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101.
Rhabdomyosarcoma (RMS) is a rare mesenchymal tumor. The aim of the present study was to develop a patient-derived orthotopic xenograft (PDOX) mouse model of RMS and compare the PDOX model to a subcutaneous (s.c.)-transplant model. A patient RMS from a striated muscle was grown orthotopically in the right biceps femoris muscle and right quadriceps muscle of nude mice to establish a PDOX model, as well as under the skin to establish an s.c. model. PDOX tumors grew at a statistically-significant faster rate compared to the s.c. tumors. Recurrence after surgical resection occurred only in PDOX tumors, not in the s.c. model. Histologically, only the PDOX model was shown to be invasive. In conclusion, these results indicate that the PDOX model of adult RMS is malignant and the subcutaneous model is benign. These results emphasize that a proper tumor microenvironment is necessary for patient-like behavior of a tumor in a mouse model.  相似文献   
102.
目的:探讨肝门部胆管癌术后口服胆汁患者的疗效。方法:采用病例对照法,回顾性分析2015年10月-2016年9月期间我科收治的肝门部胆管癌患者,术前行经皮肝穿刺胆道引流术(PTCD)并接受肝门部胆管癌根治术的患者89例,根据术后是否口服胆汁,将肝门部胆管癌患者分为两组,即口服胆汁组(51例)及对照组(38例)。所有患者均为术后3日开始进食。口服胆汁组:胆汁口服应遵循的条件为引流出的胆汁呈金黄色、无血性。术后第三天,胆汁满足口服的条件时,每6小时收集一次,经双层纱布过滤,胆汁中加入蜂蜜少量多次、随餐服下。对照组:除外口服胆汁,其余进食及治疗均相同。术后主要结局观察指标包括腹泻发生率、术后7天血清白蛋白水平,腹腔感染发生率;次要结局指标即住院时间。观察术后患者腹泻发生率、术后7天血清白蛋白水平,腹腔感染发生率和住院时间。结果:两组患者腹腔感染、腹泻发生及住院时间有统计学差异,p值均小于0.05,两组间白蛋白水平无统计学差异。结论:口服胆汁是一种有效、简便且经济的方法。术后腹腔感染并发症少,缩短住院时间,腹泻发生率较低。  相似文献   
103.
目的:探讨并对比经尿道电切术(TURBT)与经尿道双极等离子电切术治疗非肌层浸润性膀胱肿瘤(NMIBC)的疗效。方法:选取2012年1月到2016年1月在我院接受治疗的NMIBC患者76例,按照随机数字表法将患者分为观察组和对照组各38例,观察组采用经尿道双极等离子电切术进行治疗,对照组采用TURBT进行治疗。对比两组患者手术时间、术中出血量、术后导尿管留置时间、住院时间和手术并发症发生率,对比两组患者1年内复发率。结果:观察组的手术时间、术中出血量、术后导尿管留置时间、住院时间均显著少于对照组,差异有统计学意义(P0.05)。两组患者膀胱穿孔和尿道内口狭窄发生率比较差异无统计学意义(P0.05)。观察组闭孔神经反射发生率为7.89%(3/38),显著低于对照组的28.95%(11/38),差异有统计学意义(P0.05)。观察组患者1年内复发率为7.89%(3/38),对照组患者1年内复发率为10.53%(4/38),两者比较差异无统计学意义(P0.05)。结论:经尿道双极等离子电切术治疗NMIBC能有效减少手术时间、术中出血量、术后导尿管留置时间、住院时间和闭孔神经反射发生率,安全有效,与TURBT相比优势明显,值得临床推广应用。  相似文献   
104.
目的:对比分析传统开胸手术和胸腔镜下肺叶切除对老年性早期周围型肺癌的疗效及生存曲线的差异。方法:选取我院行肺癌手术治疗的患者65例,均为周围型肺癌。采用非随机对照方法,将患者随机分为传统开胸手术组和胸腔镜组,其中开胸手术组34例,胸腔镜组31例。按照既定分组方案实施手术,对比分析两组患者一般属性资料、手术相关指标;术后随访至2016年6月,采用Kaplan-Meier法对比2组患者5年总生存率(OS)、无复发生存率(RFS)。结果:胸腔镜手术组手术时间明显长于开胸组(p0.05)。胸腔镜组拔出胸腔引流管天数明显缩短(p0.05)。胸腔镜组术中出血量少于开胸组(p0.05)。胸腔镜组术后并发症发生率、VAS评分、住院时间低于开胸组(p0.05)。但胸腔镜组住院总费用多于开胸组(p0.05)。开胸组组5年RFS为65.27%,胸腔镜组67.13%,差异无统计学意义(p0.05)。开胸组患者5年OS为53.73%,胸腔镜组为55.34%,差异有统计学意义(p0.05)。结论:相比传统开胸手术,胸腔镜下早期肺癌切除术出血量少,恢复快,术后并发症发生率低,术后5年总生存率高于传统开胸术。  相似文献   
105.
目的:探讨直肠系膜切除术对直肠癌根治术后局部复发患者血清基质金属蛋白酶、肿瘤标志物(CEA、CA199)及生存率的影响。方法:收集直肠原发癌位于直肠中下段的病例,行直肠癌根治术复发再入院患者48例(均为本院2010年4月-2014年3月手术后的病例),按照手术方式的不同分为2组,分别24例。对照组采用姑息性手术治疗,研究组采用直肠系膜切除术治疗,采用ELISA法测定血清MMP-2、MMP-9、CEA、CA199水平,记录所有患者术后并发症状况,术后进行随访时间为3年,比较两组1年、3年的生存率状况。结果:对照组在手术时间、出血量、住院时间上高于研究组,(P0.05);对照组在肛门排气时间上低于研究组,(P0.05);与治疗前比较,两组患者治疗2周后MMP-2、MMP-9表达水平降低,治疗2周后血清CEA、CA199表达水平降低(P0.05);与对照组比较,研究组患者治疗2周后MMP-2、MMP-9表达水平较低,治疗2周后血清CEA、CA199表达水平较低(P0.05);两组患者治疗期间并发症无差异(P0.05);两组间术后1年生存率,无差异(P0.05);研究组术后3年生存率(66.67%)高于对照组(37.50%),(P0.05)。结论:直肠系膜切除术可提高直肠癌根治术后局部复发患者的长期生存率,降低血清MMP-2、MMP-9、CEA、CA199水平,安全性高,值得广泛推广。  相似文献   
106.
Trabecular bone is viscoelastic under dynamic loading. However, it is unclear how tissue viscoelasticity controls viscoelasticity at the apparent-level. In this study, viscoelasticity of cylindrical human trabecular bone samples (n = 11, male, age 18–78 years) from 11 proximal femurs were characterized using dynamic and stress-relaxation testing at the apparent-level and with creep nanoindentation at the tissue-level. In addition, bone tissue elasticity was determined using scanning acoustic microscope (SAM). Tissue composition and collagen crosslinks were assessed using Raman micro-spectroscopy and high performance liquid chromatography (HPLC), respectively. Values of material parameters were obtained from finite element (FE) models by optimizing tissue-level creep and apparent-level stress-relaxation to experimental nanoindentation and unconfined compression testing values, respectively, utilizing the second order Prony series to depict viscoelasticity. FE simulations showed that tissue-level equilibrium elastic modulus (Eeq) increased with increasing crystallinity (r = 0.730, p = .011) while at the apparent-level it increased with increasing hydroxylysyl pyridinoline content (r = 0.718, p = .019). In addition, the normalized shear modulus g1 (r = −0.780, p = .005) decreased with increasing collagen ratio (amide III/CH2) at the tissue-level, but increased (r = 0.696, p = .025) with increasing collagen ratio at the apparent-level. No significant relations were found between the measured or simulated viscoelastic parameters at the tissue- and apparent-levels nor were the parameters related to tissue elasticity determined with SAM. However, only Eeq, g2 and relaxation time τ1 from simulated viscoelastic values were statistically different between tissue- and apparent-levels (p < .01). These findings indicate that bone tissue viscoelasticity is affected by tissue composition but may not fully predict the macroscale viscoelasticity in human trabecular bone.  相似文献   
107.
Glaucoma is a very common disorder of the eye wherein the disturbance of the structural or functional integrity of the optic nerve causes characteristic atrophic changes in the optic nerve, which may lead to specific visual field defects over time. Primary open angle glaucoma (POAG) is most frequent among the three principle glaucoma subtypes. With well-established role of genes like Myocilin (MYOC), Optineurin (OPTN) and WD repeat Domain 36, (WDR36), at least 29 genetic loci have been found till date to be linked to POAG. Moreover, association studies have found 66 loci with 76 genes associated to POAG till date with conflicting results. This particular study is to summarize the current knowledge regarding the change in glaucoma prevalence worldwide and in India from 1993 onwards and compiles all the studied genes that are involved in POAG pathogenesis in Indian population.  相似文献   
108.
摘要 目的:探讨CD64指数、可溶性白细胞分化抗原14(sCD14)、可溶性白细胞分化抗原163(sCD163)与胸腔镜肺癌根治术后并发重症肺部感染的关系。方法:选择2020年1月至2023年1月南通市肿瘤医院收治的行胸腔镜肺癌根治术治疗的非小细胞肺癌(NSCLC)患者共415例。根据术后是否并发重症肺部感染将患者分为感染组(21例)和未感染组(394例)。检测外周血CD64指数和血清sCD14、sCD163水平。多因素Logistic回归分析影响胸腔镜肺癌根治术后并发重症肺部感染的因素。受试者工作特征(ROC)曲线分析CD64指数、sCD14、sCD163预测胸腔镜肺癌根治术后并发重症肺部感染的价值。结果:感染组外周血CD64指数、血清sCD14、sCD163水平高于未感染组(P<0.05)。多因素Logistic回归分析显示高CD64指数、sCD14、sCD163、降钙素原(PCT)是胸腔镜肺癌根治术后并发重症肺部感染的危险因素(P<0.05),高呼气峰值流量(PEF)是保护因素(P<0.05)。CD64指数、sCD14、sCD163、PCT预测胸腔镜肺癌根治术后并发重症肺部感染的曲线下面积为0.834、0.815、0.842、0.784,联合预测曲线下面积为0.928,高于单独预测。结论:血清CD64指数、sCD14、sCD163、PCT水平升高是胸腔镜肺癌根治术后并发重症肺部感染的危险因素。联合CD64指数、sCD14、sCD163、PCT可较好地预测术后重症肺部感染的风险。  相似文献   
109.
Abstract

The present paper describes a geometrically and physically nonlinear continuum model to study the mechanical behaviour of passive and active skeletal muscle. The contraction is described with a Huxley type model. A Distributed Moments approach is used to convert the Huxley partial differential equation in a set of ordinary differential equations. An isoparametric brick element is developed to solve the field equations numerically. Special arrangements are made to deal with the combination of highly nonlinear effects and the nearly incompressible behaviour of the muscle. For this a Natural Penalty Method (NPM) and an Enhanced Stiffness Method (ESM) are tested. Finally an example of an analysis of a contracting tibialis anterior muscle of a rat is given. The DM-method proved to be an efficient tool in the numerical solution process. The ESM showed the best performance in describing the incompressible behaviour.  相似文献   
110.
The intrinsic permeability of bone plays an important role in the transport of nutrients and minerals within the tissue, and affects the mechanical stimuli that are related to the fate of the stem cells. The objective of this study was to establish a method to assess trabecular bone permeability using experimental and finite element (FE) modeling approaches based on micro computed tomography (µCT) images. Human cadaveric tibia cube specimens (N=23) were scanned with µCT. The permeability was measured experimentally using a custom-developed constant-head permeameter, and computationally by a poroelastic formulation to simulate the fluid flow within the discretized bone matrix and pore phase. The average of the experimentally measured permeability was 4.84×10−10 m2 with a standard deviation of 3.70×10−10 m2. A regression model of the µCT determined that the maximum bone area to total area ratio (maxBA/TA) for all slices that are perpendicular to the direction of fluid flow explained 84% of the variability of the natural logarithm of the experimentally measured permeability. The 2D measure of maxBA/TA performed better than 3D measures in general, although some parameters were reasonably well associated with permeability such as bone volume ratio (BV/TV, r=−0.71), the bone surface/bone volume (BS/BV, r=0.73), and the trabecular thickness (TbTh, r=−0.71). The correlation between the permeability predicted with FE models and experimentally measured permeability was reasonable (r=0.69), but the FE approach did not accurately represent the wide variability of permeability measured experimentally. The results of this study suggest that the changes in the trabecular bone microarchitecture have an exponential relationship with permeability, and the use of µCT-based 2D measurement of maxBA/TA performs well at predicting permeability, thus providing a convenient approach to measure this important aspect affecting biomechanical functions in the tissue.  相似文献   
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