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11.
Thirty-five patients (23 males) with asymptomatic hyperuricemia for at least two years underwent two-dimensioal ultrasonography of knees and ankles. Urate deposits (tophi) in tendons, synovium, and other soft tissues were detected in 12 patients (34%). Increased vascularity (inflammation) was evident in 8 of these patients (23%). Tophi were more frequently found in knees than in ankles and were especially prevalent in the distal patellar tendon. The presence of tophi was unrelated to the known duration of hyperuricemia (mean, 5 years). Ultrasonography allows detection of tophi and inflammation in a third and in a fourth, respectively, of asymptomatic hyperuricemic patients.  相似文献   
12.
Technical aspects of creating an arteriovenous fistula in the mouse are discussed. Under general anesthesia, an abdominal incision is made, and the aorta and inferior vena cava (IVC) are exposed. The proximal infrarenal aorta and the distal aorta are dissected for clamp placement and needle puncture, respectively. Special attention is paid to avoid dissection between the aorta and the IVC. After clamping the aorta, a 25 G needle is used to puncture both walls of the aorta into the IVC. The surrounding connective tissue is used for hemostatic compression. Successful creation of the AVF will show pulsatile arterial blood flow in the IVC. Further confirmation of successful AVF can be achieved by post-operative Doppler ultrasound.  相似文献   
13.
周兢  李自清  徐琳琳  朱琳娜  高玉树  黄越 《生物磁学》2013,(35):6949-6951,6955
目的:探讨彩色多普勒超声技术测量椎动脉血流量对后循环缺血(PCI)的诊断价值。方法:选取2012年1月至2013年1月在本院神经内科住院并接受治疗的PCI患者58例作为观察组,另选取同期住院并确诊为非后循环缺血症的患者50例作为对照组。所有患者均接受颈部血管超声检查,测量椎动脉内径及血流量,观察组患者需行头颅CTA检查,比较两组患者的椎动脉内径、血流量及颈动脉硬化斑块发生率等。结果:观察组患者的椎动脉内径及血流量明显低于对照组,两组比较差异有统计学意义(P〈0.01);观察组颈动脉硬化斑块的发生率为77.5%(44例),对照组颈动脉硬化斑块的发生率为42%(21例),两组比较差异有统计学意义(P〈0.05)。无狭窄、轻度狭窄、重度狭窄及闭塞的椎动脉血流量的变化(此处所指的血流量是指小于200mL/min那部分患者)有明显差异(P〈0.05)。结论:与头颅CTA对比检查,彩色多普勒具有直接、准确、方便及可重复性等优点,可有效的诊断后循环缺血症状。  相似文献   
14.
15.
The beef industry has emphasized the improvement of feed utilization, as measured by modeling feed intake through performance traits to calculate residual feed intake (RFI). Evidence supports an inverse relationship between feed efficiency and reproductive function. The objective of this study was to determine the relationship of reproductive assessments and RFI unadjusted (RFIKoch) or adjusted for body composition (RFIus) and the relationship among fertility-related parameters. In total, 34 crossbred bulls were housed together for 112 days of performance evaluation, followed by assessment of scrotum IR imaging, scrotal circumference, testes ultrasonography and semen quality parameters at 377±33.4 days of age. Bulls were slaughtered at 389±34.0 days of age, and analyses of carcass composition, biometrics and histomorphometry of the testis and epididymis were conducted. Bulls were grouped into two subpopulations based on divergence of RFI, and within each RFI model either by including 50% of the population (Halves, high and low RFI, n=17) or 20.6% extremes of the population (Tails, high and low RFI, n=7). The means of productive performance and fertility-related measures were compared through these categories. Pearson’s correlation was calculated among fertility-related measures. In the Halves subpopulation of the RFIus, sperm of low-RFI bulls had decreased progressive motility (47.30% v. 59.90%) and higher abundance of tail abnormalities (4.30% v. 1.80%) than that of high-RFI bulls. In the Tails subpopulation of the RFIKoch, low RFI displayed less variation in the scrotum surface temperature (0.62°C v. 1.16°C), decreased testis echogenicity (175.50 v 198.00 pixels) and larger (60.90 v. 56.80 mm2) but less-developed seminiferous tubules than high-RFI bulls. The evaluation of fertility-related parameters indicated that a higher percentage of immature seminiferous tubules was correlated with occurrence of sperm with distal droplets (r=0.59), a larger temperature variation at the top of the scrotum was correlated with improved sperm progressive motility (r=0.38), a lower occurrence of sperm loose head abnormalities was correlated with larger temperature variation at the lower part of the scrotum (r=−0.43), and a lower minimum testis echogenicity (r=−0.59) and smaller scrotal circumference (r=0.72) were correlated with age. The adjustment for body composition (RFI determination) enabled distinct biological inferences about reproduction and feed efficiency when compared with the non-adjusted model. However, both RFI models and the correlation analysis supported the hypothesis that feed-efficient bulls have features of delayed sexual maturity. Overall, the assessment of fertility-related measurements is important to avoid the improvement of feed efficiency at the expense of reproductive function in young bulls.  相似文献   
16.
目的:探讨超声内镜(EUS)辅助下内镜黏膜下切除术(EMR)对食管癌前病变患者肿瘤标志物及应激反应指标的影响。方法:选择山东大学齐鲁医院青岛院区消化内科于2016年3月至2018年4月期间收治的食管癌前病变患者137例,采用随机数字表法将患者分为常规组(n=68,常规胃镜下行EMR)和EUS组(n=69,EUS辅助下行EMR),比较两组患者临床指标,比较两组术前、术后血清肿瘤标志物及应激反应指标水平,比较两组术前、术后1周相关遗传学分子水平。结果:EUS组手术时间、术后流质饮食时间均短于常规组(P0.05),并发食管黏膜小穿孔例数、使用钛夹止血例数均少于常规组(P0.05)。两组患者术后肿瘤特异性生长因子(TSGF)、细胞角蛋白19血清片段21-1(CYFRA21-1)、鳞状上皮细胞癌抗原(SCC-Ag)均较术前升高,但EUS组低于常规组(P0.05)。两组患者术后肾上腺素(E)、去甲肾上腺素(NE)、肾素(R)、血管紧张素Ⅱ(AngⅡ)、醛固酮均较术前升高,但EUS组低于常规组(P0.05)。两组患者术后1周细胞周期素E(Cyclin E)、转化生长因子-α(TGF-α)均较术前降低,且EUS组低于常规组(P0.05)。结论:相比于常规胃镜,经EUS辅助下EMR治疗食管癌前病变可有效改善患者的临床指标,减轻患者应激反应,有利于降低血清肿瘤标志物及遗传学分子水平。  相似文献   
17.
目的:探讨肺脏超声对新生儿呼吸窘迫综合征(NRDS)的诊断价值,并分析肺超声评分的临床应用价值。方法:本研究选择2017年5月至2018年5月于我院确诊的NRDS患儿45例作为观察组,选择同期于我院就诊的非肺病患儿45例作为对照组,所有患儿均行肺脏超声检查。分析NRDS患儿肺脏超声特征性征象,比较肺脏超声对两组患儿各种征象的检出率,分析肺脏超声对NRDS的诊断价值,比较两组肺超声评分。结果:NRDS患儿全部存在肺实质征象,超声下肺组织回声呈肝样伴支气管充气征,轻度的NRDS患儿于肺脏超声下表现为局灶性的肺实质,且支气管充气征不明显;重度的NRDS患儿于肺脏超声下表现为肺实质范围的进一步扩大,且支气管充气征随病情的加重而愈发明显。观察组肺实质、胸膜线异常、A线消失、弥漫性肺水肿、支气管充气征等征象的检出率显著高于对照组(P0.05),两组B线存在征象的检出率比较无统计学差异(P0.05)。肺实质、胸膜线异常和A线消失三种特征征象同时存在时对NRDS诊断的灵敏度和特异性均为100.00%,肺实质、胸膜线异常和支气管充气征三种特征征象同时存在时对NRDS诊断的灵敏度为80.00%,特异性为100.00%。观察组双肺、左肺、右肺、双侧肺、双肺底肺超声评分均高于对照组(P0.05)。结论:肺脏超声对NRDS的诊断价值较高,且肺超声评分可以评估NRDS患儿的病情严重程度,有助于指导患儿的治疗。  相似文献   
18.
The dynamic light scattering methods are widely used in biomedical diagnostics involving evaluation of blood flow. However, there exist some difficulties in quantitative interpretation of backscattered light signals from the viewpoint of diagnostic information. This study considers the application of the high‐speed videocapillaroscopy (VCS) method that provides the direct measurement of the red blood cells (RBCs) velocity into a capillary. The VCS signal presents true oscillation nature of backscattered light caused by moving RBCs. Thus, the VCS signal can be assigned as a reference one with respect to more complicated signals like in laser Doppler flowmetry (LDF). An essential correlation between blood flow velocity oscillations in a separate human capillary and the integral perfusion estimate obtained by the LDF method has been found. The observation of blood flow by the VCS method during upper arm occlusion has shown emergence of the reverse blood flow effect in capillaries that corresponds to the biological zero signal in the LDF. The reverse blood flow effect has to be taken into account in interpretation of LDF signals.   相似文献   
19.
目的:研究健康体检人群甲状腺结节多普勒超声检查结果及影响因素。方法:将从2018年1月~2019年12月,于医院接受体检的健康体检人员5270例纳入研究,对所有受试者均进行多普勒超声检查,分析超声检查结果和体检人群基线资料的关系,分析甲状腺结节多普勒超声特征。采用单因素以及多因素Logistic回归分析健康体检人群甲状腺结节的影响因素。结果:在5270例健康体检人群中,甲状腺结节检出率为51.86%(2733/5270),女性甲状腺结节检出率为52.83%(2355/4458),高于男性的46.55%(378/812),且随着年龄的不断增长,健康体检人群甲状腺结节检出率呈逐渐升高趋势(均P<0.05)。甲状腺结节患者的多普勒超声检查特征以低回声以及结节直径<2 cm为主(均P<0.05),但是结节数目以及病变部位比较无明显差异(均P>0.05)。经单因素分析发现:吸烟、甲状腺疾病家族史、高血压及糖尿病的健康体检人员甲状腺结节检出率高于不吸烟、无甲状腺疾病家族史、无高血压及无糖尿病的健康体检人员(均P<0.05),而不同民族、受教育年限、体质量指数(BMI)、是否饮酒的健康体检人员甲状腺结节检出率比较无统计学差异(均P>0.05)。经多因素Logistic回归分析发现:女性、年龄、吸烟、甲状腺疾病家族史、高血压及糖尿病均是健康体检人群甲状腺结节发生的独立危险因素(均OR>1,P<0.05)。结论:甲状腺结节多普勒超声检查特征以低回声以及结节直径≤2 cm为主,其影响因素包括年龄、性别、吸烟、甲状腺疾病家族史、高血压及糖尿病,值得临床重点关注。  相似文献   
20.
摘要 目的:分析心脏彩超检查联合血清B型钠尿肽(BNP)、白蛋白(ALB)、胱抑素C(CysC)在慢性心力衰竭(CHF)患者预后评估中的临床价值。方法:选取2017年6月-2018年5月我院收治的123例CHF患者,心脏彩超检查左心室射血分数(LVEF)、左心房内径(LAD)和左心室内径(LVD),实验室检测血清BNP、ALB、CysC水平。按照3年随访后患者是否死亡分为死亡组35例和存活组88例,收集临床资料,采用多因素Logistic回归分析CHF患者预后的影响因素。采用受试者工作特征(ROC)曲线分析心脏彩超检查联合血清BNP、ALB、CysC对CHF患者预后的评估价值。结果:死亡组患者的LAD、LVD及血清BNP、CysC水平高于存活组患者,而LVEF及血清ALB水平低于存活组患者(P<0.05)。心脏彩超指标LVEF、LAD、LVD及血清BNP、ALB、CysC是CHF患者预后的影响因素(P<0.05)。心脏彩超指标LVEF、LAD、LVD联合血清BNP、ALB、CysC检测对CHF患者预后评估的ROC曲线下面积(AUC)(0.95CI)为0.857(0.771~0.938),灵敏度及特异度分别为0.914(32/35)、0.795(70/88),均明显高于上述各指标单独检测。结论:心脏彩超指标LVEF、LAD、LVD和血清BNP、ALB、CysC均为CHF患者预后的影响因素,且联合检测对患者预后的评估价值较高,具有一定的临床应用价值。  相似文献   
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