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11.
目的:探讨直立倾斜试验对儿童不明原因晕厥的诊断价值,为临床诊断提供科学依据。方法:对208例不明原因晕厥的儿童给予进行直立倾料试验检查,持续进行心电监护监测,记录其血压、心率变化,分析试验结果。结果:145例(69.71%)出现阳性的血管迷走神经反应,73例(50.34%)为血管抑制型反应;19例(13.10%)呈心脏抑制型反应;53例(36.55%)为混合型反应型,并且诱发因子多为持久站立。结论:不明原因晕厥患者在直立倾斜试验中以血管迷走反应为主,持久站立是血管迷走神经性晕厥的主要诱因。  相似文献   
12.
目的:探讨经会阴二维超声对自然分娩女性产后盆底三腔室运动和早期盆底功能的评估价值。方法:选取2019年2月~2019年7月于我院进行自然分娩的产妇284例作为研究组,另选取同期于我院接受诊治的未育女性200例作为对照组。两组均进行经会阴二维超声检查,比较两组静息期、张力期、缩肛期的肛管直肠连接部(ARJ)、宫颈外口(CV)、尿道膀胱连接部(UVJ)的位置及运动变化情况,对比两组静息状态下以及最大Valsaval动作下盆底超声参数。结果:研究组静息期、张力期、缩肛期的CV距离水平参照线的垂直长度(CV-VD)、UVJ距离水平参照线的垂直长度(UVJ-VD)均低于对照组(均P0.05)。研究组张力期对应静息期垂直长度△r-s CV-VD、△r-s UVJ-VD均高于对照组,而缩肛期对应静息期垂直长度△r-s CV-VD、△r-s UVJ-VD均低于对照组(均P0.05)。研究组静息状态下膀胱颈位置(BNP)低于对照组,而膀胱尿道后角(PUA)高于对照组(均P0.05);研究组最大Valsaval动作下膀胱颈移动度(BND)、PUA、尿道旋转角(URA)均高于对照组(均P0.05)。结论:经会阴二维超声可对自然分娩女性产后盆底三腔室运动和早期盆底功能进行有效观察,有助于评估女性盆底结构、功能变化,具有一定的临床推广应用价值。  相似文献   
13.
卧床前后压力感受性反射机能变化的研究   总被引:2,自引:0,他引:2  
许多数据表明长期失重以后立位耐力降低可能与压力感受性反射功能的改变有关。本文比较了两组被试者15天低动力卧床前后的立位耐力。以血压调节模型为基础分析了两种不同方式卧床前后单纯立位和下身负压加立位时压力感受性反射功能的改变,并用颈部加压及下身负压对中枢调节功能改变进行了观察。结果表明严格的头低位卧床后,立位耐力下降及压力感受性反射功能改变明显大于半日平卧半日倚坐者。而压力感受性反射功能的改变,特别是中枢神经系统调节功能的紊乱,是卧床后立位耐力降低的主要原因。从这种考虑为基础,作者提出了改变失重或模拟失重状态下的血液分布,调整对压力感受器的刺激,可能是预防心血管失调的有效方法。  相似文献   
14.
目的:探讨女性盆底功能障碍性疾病的相关因素及盆底超声测定压力性尿失禁SUI的临床意义。方法:选取我院2019年-2020年共收治的63例盆底功能障碍性疾病患者作为研究对象,将其分为研究组,另取同期来我院进行体检的63例健康女性作为对照组,对所有女性应用盆底超声检测,对比两组女性静息状态下和Valsalva状态下的盆底超声检查指标,对通过问卷调查方式,调查两组女性的一般临床治疗,对于女性盆底功能障碍性疾病的相关因素进行单因素分析与多因素分析,最终得出盆底肌功能障碍性疾病的相关因素。结果:在静息状态下通过盆底超声发现,研究组与对照组膀胱尿道后角、肛提肌裂孔面积、尿道倾斜度对比差异显著(P<0.05),两组女性膀胱颈位置、膀胱位置对比无明显差异(P>0.05);在Valsalva状态下通过盆底超声发现,研究组与对照组膀胱尿道后角、肛提肌裂孔面积、尿道倾斜度、膀胱颈位置、膀胱位置对比差异显著(P<0.05);两组女性年龄、BMI、孕次、产次、绝经情况以及白带清洁度是否≥Ⅲ度情况对比差异显著(P<0.05),两组女性子宫肌瘤史情况对比无显著差异(P>0.05);logistic回归分析结果显示,年龄、绝经情况、子宫肌瘤史和白带清洁度≥Ⅲ度不是盆底功能障碍性疾病的独立危险因素(P>0.05),BMI、孕次、产次为盆底功能障碍性疾病的独立危险因素(P<0.05)。结论:盆底肌超声在对盆底功能障碍性疾病患者压力性尿失禁的诊断中具有重要价值,在静息状态下和Valsalva状态下发现患者的膀胱经移动情况与尿道倾斜情况。年龄、BMI、孕次、产次、绝经情况以及白带清洁度是否≥Ⅲ度可能与盆底功能障碍性疾病具有一定关系,BMI、孕次、产次为盆底功能障碍性疾病的独立危险因素。  相似文献   
15.
Several investigators have suggested the presence of a link between Chronic Low Back Pain (CLBP) and lower limbs kinematics that can contribute to functional limitations and disability. Moreover, CLBP has been connected to postural and structural asymmetry. Understanding the movement pattern of lower extremities and its asymmetry during walking can provide a basis for examination and rehabilitation in people with CLBP. The present study focuses on lower limbs kinematics in individuals with CLBP during walking. Three-dimensional movements of the pelvic, hip, knee and ankle joints were tracked using a seven-camera Qualysis motion capture system. Functional dada analysis (FDA) was applied for the statistical analysis of pelvic and lower limbs motion patterns in 40 participants (20 CLBP and 20 controls). The CLBP group showed significantly different hip motion pattern in the transvers plane, altered knee and ankle motion pattern in the sagittal plane on the dominant side and different hip motion pattern in the transvers and frontal planes on the non-dominant side in comparison with the control group over the stance phase. In terms of symmetry, in the CLBP group, hip and knee moved through a significantly different motion patterns in the transvers plane on the dominant side in comparison with the non-dominant side. In the control group, knee moved through a significantly different motion pattern in the transvers plane on the dominant side in comparison with the non-dominant side. In conclusion, low back pain lead to altered movement patterns of the main joints of lower limbs especially on the dominant side during stance phase. Therefore, care should be taken to examine dominant lower limb movement pattern in CLBP to make a better clinical decision.  相似文献   
16.
目的:探讨P物质(substance P,SP)在子宫内膜异位症(endometriosis,EM)中的表达及其意义。方法:采用免疫组织化学法检测2012年10月至2013年4月在哈尔滨医科大学附属第一医院经腹腔镜及病理证实的EM患者异位子宫内膜组织20例,与其配对的在位子宫内膜组织10例以及因非EM(子宫肌瘤)行腹腔镜下子宫全切术或肌瘤核除患者的正常子宫内膜组织20例中SP的表达情况,并分析和比较术中盆腔粘连发生情况。结果:SP在EM患者的异位子宫内膜、在位子宫内膜及非EM患者的正常子宫内膜的阳性表达率分别为75%、80%、20%,异位子宫内膜和在位子宫内膜比较无显著性差别(P=1.0),但均高于非EM患者的正常子宫内膜,差异均有统计学意义(P=0.002,P=0.004);EM组盆腔粘连的阳性率高于非EM组,EM患者异位子宫内膜中SP阳性组盆腔粘连阳性率高于SP阴性组,差异均有统计学意义(P=0.001,P=0.032),非EM患者正常子宫内膜中SP阳性组盆腔粘连阳性率与SP阴性组相比,差异不具有统计学意义(P=0.061)。结论:SP在EM的异位子宫内膜和在位子宫内膜中的表达上调,并与EM合并盆腔粘连有关,其具体机制尚有待进一步的研究。  相似文献   
17.
Assemblies of Photosystem II and light-harvesting proteins were purified from the liverwort Marchantia polymorpha and investigated by two- and three-dimensional transmission electron microscopy of negatively stained specimens. By single-particle analysis, it was determined that about 25% of the particles are rectangular or slightly S-shaped with dimensions of 285 A in length, 144 A in width, 84 A in height, while the membrane part is about 52 A thick. This structure reveals the same architecture as that of a Photosystem II-light-harvesting assembly from seed plants. An overlay of the projection structure of the liverwort's complex with a projection structure deduced from stained trimeric LHC II crystals from pea confirmed the locations of trimeric LHC II within the liverwort's complex. Remarkably tight associations of LHC II and other chlorophyll a/b binding proteins with the PS II core complex are observed. More than 50% of the Photosystem II particles from the liverwort carry one or two additional masses. These extra masses are found to consist of an additional LHC II trimer and probably a chlorophyll a/b binding protein. For the first time, a three-dimensional structure of such a large assembly is defined.  相似文献   
18.
摘要 目的:探讨电针阴部神经刺激疗法联合Kegel盆底康复训练对产后压力性尿失禁(SUI)患者盆底肌力、尿流动力学和生活质量的影响。方法:选取2019年6月~2021年11月期间于我院就诊的产后SUI患者109例,按照入院就诊奇偶顺序分为两组,其中对照组54例,接受Kegel盆底康复训练,研究组55例,接受电针阴部神经刺激疗法联合Kegel盆底康复训练。对比两组疗效、漏尿量、尿失禁程度、盆底肌力、尿流动力学和生活质量。结果:研究组的临床总有效率高于对照组(P<0.05)。两组治疗后盆底肌肌力各指标(手测肌力和Ⅰ类肌纤维最大值、Ⅱ类肌纤维平均值)均升高,且研究组高于对照组(P<0.05)。两组治疗后漏尿量、尿失禁程度评分均下降,且研究组低于对照组(P<0.05)。两组治疗后尿流动力学相关指标[腹压漏尿点压(AL-PP)、最大尿流率(Qmax)和最大尿道闭合压力(MUCP)]均升高,且研究组高于对照组(P<0.05)。两组治疗后尿失禁生活质量量表(I-QOL)各维度(限制性行为、心理影响、社交活动受限)评分及总分均升高,且研究组高于对照组(P<0.05)。结论:电针阴部神经刺激疗法联合Kegel盆底康复训练可有效改善产后SUI患者的盆底肌肌力和尿失禁情况,减少漏尿量,同时可促进尿流动力学恢复,进而提高患者的生活质量。  相似文献   
19.
NADPH-diaphorase (NADPH-D) activity and immunoreactivity for neural and endothelial nitric oxide synthase (nNOS and eNOS, respectively) were used to investigate nitric oxide (NO) regulation of penile vasculature. Both the histochemical and immunohistochemical techniques for NOS showed that all smooth muscles regions of the penis (dorsal penile artery and vein, deep penile vessels, and cavernosal muscles) were richly innervated. The endothelium of penile arteries, deep dorsal penile vein, and select veins in the crura and shaft were also stained for NADPH-D and eNOS. However, the endothelium of cavernous sinuses was unstained by both techniques. Fewer fibers were seen in the glans penis, those present being associated with small blood vessels and large nerve bundles near the trabecular walls. All penile neurons in the pelvic plexus, located by retrograde transport of a dye placed in the corpora cavernosa penis, were stained by the NADPH-D method. Essentially similar results were obtained with an antibody to nNOS. These data suggest that penile parasympathetic neurons comprise a uniform population, as all seem capable of forming nitric oxide. However, in contrast to the endothelium of penile vessels, the endothelium lining the cavernosal spaces may not be capable of nitric oxide synthesis.  相似文献   
20.
A hydrophobic pulmonary surfactant protein, SP-C, has been implicated in surface-associated activities thought to facilitate the work of breathing. Model surfactant films composed of lipids and SP-C display a reversible transition from a monolayer to surface-associated multilayers upon compression and expansion at the air/water (A/W) interface. The molecular-level mechanics of this process are not yet fully understood. The current work uses atomic force microscopy on Langmuir–Blodgett films to verify the formation of multilayers in a dipalmitoylphosphatidylcholine, dipalmitoylphosphatidylglycerol, cholesterol, and SP-C model system. Isotherms of SP-C-containing films are consistent with exclusion and essentially complete respreading during compression and expansion, respectively. Multilayer formation was not detected in the absence of SP-C. Most notable are the results from IR reflection–absorption spectroscopy (IRRAS) conducted at the A/W interface, where the position and intensity of the Amide I band of SP-C reveal that the predominantly helical structure changes its orientation in monolayers versus multilayers. IRRAS measurements indicate that the helix tilt angle changed from approximately 80° in monolayers to a transmembrane orientation in multilayers. The results constitute the first quantitative measure of helix orientation in mixed monolayer/multilamellar domains at the A/W interface and provide insight into the molecular mechanism for SP-C-facilitated respreading of surfactant.  相似文献   
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