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51.
Infertility is a major health issue affecting over 48.5 million couples around the world, with the male factor accounting for about 50% of the cases. The conventional semen analysis recommended by the World Health Organization (WHO) is the cornerstone in the evaluation of male fertility status. It includes macroscopic and microscopic evaluation of the ejaculate, which reflects the production of spermatozoa in the testes, the patency of the duct system and the glandular secretory activity. Evaluation of seminal fructose, sperm vitality and leucocytes (Endtz test) are useful adjuncts to semen analysis that provide information on specific clinical conditions. Though several computer-assisted sperm analysis (CASA) systems have been developed, conventional methods for semen analysis are still widely accepted in clinical practice. This review summarises the conventional techniques used in routine semen analysis and their diagnostic value in clinical andrology.  相似文献   
52.
目的观察不同b值条件下心脏体素内不相干运动(IVIM)成像相关参数的一致性。方法对30名健康志愿者行左心室中间部IVIM扫描,以双指数模型获取IVIM参数值慢速表观弥散系数(ADCslow)、快速ADC(ADCfast)及灌注分数f。比较9个b值(0、20、50、80、100、120、200、300、500 s/mm^2)与7个b值(0、20、80、100、200、300、500 s/mm^2)条件下所测参数值的差异,采用组内相关系数(ICC)分析2名医师测量参数结果的一致性,以Bland-Altman检验分析不同b值条件下所测参数的一致性。结果9个与7个b值条件下ADCslow、ADCfast及f差异均无统计学意义(P均>0.05),且2名医师测量IVIM参数的组内及组间一致性均较好(ICC均≥0.66,P均<0.05)。Bland-Altman图显示,9个与7个b值时ADCslow的平均偏差为-0.07×10-3 mm^2/s,一致性界限(-1.87,1.73);ADCfast的平均偏差1.57×10-3 mm^2/s,一致性界限(-72.64,75.77);f的平均偏差1.17%,一致性界限(-13.45,15.79)。结论9个与7个b值条件下心脏IVIM成像各参数值的一致性较好。  相似文献   
53.
目的:分析子痫前期(PE)患者血清甲胎蛋白(AFP)、D-二聚体(D-dimer)及胎盘生长因子(PLGF)水平对母体及妊娠结局的影响。方法:将本院2016年1月-2018年9月收治的330例PE患者分轻度PE组(n=117)、重度PE组(n=213),另选同期本院住院待产的正常妊娠产妇30例为对照组,检测各组孕妇血清AFP、D-dimer、PLGF水平,绘制受试者工作特征(ROC)曲线分析对PE的诊断预测效能;Spearman相关性分析各检测指标与病情的相关性;对PE患者妊娠结局的预测效能。结果:PE组与对照组AFP比较无差异(P>0.05),但D-dimer水平PE组高于对照组,PLGF低于对照组(P<0.05);D-dimer AUC值最高(387.51μg/L),预测PE的敏感度、特异度为80.6%、100.0%;PLGF AUC值次之(217.33pg/ml),预测PE的敏感度为96.7%,高于D-dimer。不同病情严重程度的PE患者血清AFP、PLGF水平未见差异(P>0.05),但D-dimer轻度PE组低于重度PE组(P<0.05)。AFP与PE病情程度未见相关性(r=0.093,P=0.078),D-dimer与PE病情程度正相关(r=0.796,P=0.000),PLGF与PE病情程度负相关(r=0.114,P=0.031)。PE患者中,母体发生并发症、胎儿结局不良者血清D-dimer水平高于无并发症、胎儿结局良好者(P<0.05),AFP、PLGF未见差异(P>0.05);D-dimer对PE患者并发症可发挥一定预测效能,以579.53μg/L为cut-off,预测PE患者并发症的敏感度、特异度为80.9%、61.9%,另两项血清指标对妊娠结局的预测效能不佳。结论:血清AFP、D-dimer、PLGF3个指标中,D-dimer对PE的预测价值及其与PE病情的相关性最为显著,用于预测PE患者母体并发症具有一定敏感度,但特异度不佳。  相似文献   
54.
猪粪饲养家蝇幼虫的营养成分研究   总被引:3,自引:3,他引:0  
目的 :分析猪粪饲养家蝇 (Muscadomestica)幼虫的营养成分。方法 :引种野生家蝇 ,用猪粪饲养幼虫 ,收获 3期老熟幼虫 ,测定粗蛋白、粗脂肪、氨基酸和脂肪酸构成及微量元素含量 ,用粮食与农业组织 世界卫生组织 (FAO WHO)提出的参考蛋白模式评价 ,并与麦麸饲养的幼虫及鱼粉比较。结果 :每公斤猪粪平均可产(0 13± 0 0 4)~ (0 2 0± 0 12 )kg鲜蛆 ,鲜蛆烘干比为 1∶0 31± 0 12 ,粗蛋白 42 36 %~ 5 2 33 % ,必须氨基酸含量占总氨基酸的 45 10 % (E % ) ,必须氨基酸与非必需氨基酸总量的比值 (E/N)为 0 82 ,E % /T为 3 0 1,脂肪酸含量为 13 73 %~ 16 83 % ,油酸、亚油酸及亚麻酸等必需脂肪酸分别为 36 99% ,7 6 1%和 0 35 % ,Fe 2 91 5mg/kg ,Cu 87 5 5mg/kg ,Zn 2 46 8mg/kg ,Mn 2 49 45mg/kg ,比麦麸饲养幼虫更接近参考蛋白模式 ,营养价值优于鱼粉。结论 :猪粪饲养的家蝇幼虫比麦麸饲养的幼虫更接近参考蛋白模式 ,营养价值优于鱼粉  相似文献   
55.
Several scores based on symptoms and signs have been developed to assess the presence of heart failure. The goal of this study was to compare six heart failure scores in non-hospitalised subjects and to determine their usefulness in population based research. The scores were applied to 54 participants of a population based study. All underwent a complete medical examination, including chest X-ray, electrocardiography and Doppler echocardiography. Using all information available, a cardiologist, unaware of the results of the scores, clinically classified participants as having no, possible or definite heart failure. Sensitivity, specificity, predictive values and receiver operating characteristics were calculated, using the cardiologist's assessment as a gold standard. The cardiologist judged definite or possible heart failure to be present in 17 persons. All scores had a high sensitivity for the detection of definite heart failure, whereas the study of men born in 1913 and Walma's score had the highest sensitivity for the combination of possible and definite heart failure. Gheorgiade's and the Boston score had the highest positive predictive values. In conclusion, five of the six scores we studied are broadly similar in the detection of heart failure. The men born in 1913 score relies heavily on the assessment of dyspnea, resulting in a relatively large number of false positives. Although the scores are useful in detecting manifest heart failure, objective measurements of cardiac function appear necessary to reduce the false positive rate and accurately detect early stages of heart failure.  相似文献   
56.
The aim of the present study was to evaluate the effect of age and human papillomavirus (HPV) infection associated cellular changes on the predictive value of cervical cytology. In a group of 671 women with Papanicolaou smears suggesting low grade squamous intraepithelial lesion (LSIL), high grade squamous intraepithelial lesion (HSIL) or invasive cervical cancer, cervical cytology was correlated with the histological finding. Predictive values were calculated and related to severity of the lesion, age and HPV associated changes. The predictive values of Papanicolaou (cervical) smears suggesting LSIL, HSIL and invasive carcinoma were 40%, 86%, and 78%, respectively. A poor predictive value of smears suggesting LSIL was found among older women. HPV associated changes were diagnosed in 80% of women 25 years of age, 66% in the age group 26 to 35 years, 51% in the age group 36 to 45 years and 38% in women aged 46 years (P = 0.03). The presence of HPV associated cellular changes led to a significantly higher number of overdiagnoses (9% with HPV infection compared to 4% without HPV infection) and HPV negative cases were more frequently associated with underdiagnosis (15% without HPV infection compared to 8% with HPV infection,P = 0.0011). This result remained significant after adjustment for age (P = 0.004). Cellular changes associated with HPV infection most frequently occurred in young women. HPV infection should therefore be acknowledged as source of overdiagnosis in the cytological evaluation of SIL especially in woung women.Supported by the Research Grant of the Mayor of Vienna (no. 1045 [to Dr. Kainz])  相似文献   
57.
Urinary delta-aminolaevulinic acid (-ALA) excretion was evaluated in random urine samples of 191 healthy children, aged 2–14 years, with blood lead levels <0.8 mol/l (mean ± SD: 0.34±0.13), erythrocyte zinc-protoporphyrin <70 mol/mol haem (mean ± SD: 50.4±8.0) and blood haemoglobin >6.8 mmol/l (mean ± SD: 8.2±0.5). It was found that uncorrected -ALA concentration and -ALA/creatinine ratio are age-dependent, whereas the ratio of -ALA/logarithm of creatinine concentration (mean ± SD: 55.3±13.5 mol/log mmol) is independent of age and sex. The authors recommend the use of this parameter for the assessment of -ALA excretion in random urine samples in children  相似文献   
58.
目的:为制定中国健康中青年女性全血比粘度参考值的统一标准提供科学依据。方法:收集了中国各地用毛细管法测定的健康中青年女性全血比粘度参考值,并对其与海拔高度的关系进行了研究。结果:发现随着海拔高度的逐渐增大,健康中青年女性全血比粘度参考值也在逐渐增大,相关性很显著。用一元回归分析的方法推导出一个回归方程。结论:如果知道了中国某地的海拔高度,就可以用回归方程估算这个地区的健康中青年女性全血比粘度参考值。  相似文献   
59.
短小芽胞杆菌E601抗电离辐射性的研究   总被引:1,自引:0,他引:1  
目的 短小芽胞杆菌E601 已在中国确定为辐射灭菌指示菌。为使指示菌在灭菌过程中的应用标准化、规范化,保证灭菌质量,需要对其固有抗辐射性和影响因素,以及如何制备抗辐射稳定的生物指示剂作详尽研究。方法 应用钴60γ射线和高能电子束对短小芽胞杆菌E601 进行辐照,测定不同条件下的D10 值。结果 ①因载体、介质不同,D10 值变化在1 .60 ~2.53kGy 之间。②不同温度下保存一年,指示菌片芽胞抗辐射性无明显变化。但随着保存时间延长,菌片上存活菌数逐渐减少。③载体、介质影响存活率,电子束与钴60 结果一致。结论 短小芽胞杆菌D10 值在1 .60~2.53kGy 之间,且抗性稳定。本试验条件下制备的可溶性菌片抗力高,D10 值为2 .53kGy,可长期保存,适宜作指示剂应用  相似文献   
60.
Objective: This study investigated the relative value of adverse drug events reported by doctors, nurses and patients. Methods: The study was conducted on a total of four wards: the paediatric and internal medicine wards (including geriatric patients) of two peripheral hospitals in the Netherlands. Adverse drug events were collected by spontaneous reporting (doctor and nurse reports) and by daily ward visits, during which the patients were interviewed by a hospital pharmacist (patient reports). Criteria for relative value of the reported adverse drug events were the number of potentially serious reactions, the number of reactions not mentioned in the patient information leaflet and the number of reactions reported to new drugs (5 years or less on the Dutch market). No formal causality assessment was applied. Results: Over a period of 2 months in 1996 (Hospital I) and 2 months in 1997 (Hospital II) a total of 620 patients were included in the study and adverse drug events were reported in 179 (29%) of these cases. Doctors reported a statistically significant larger number of serious (26% of all doctor reports; odds ratio (OR) 3.2; confidence interval (CI) 1.2–8.7) and unknown (39%; OR 2.5; CI 1.0–6.0) adverse drug events than patients themselves during the daily ward visit. Doctors also reported more serious and unknown adverse drug events than nurses. Adverse reactions to new drugs were reported during the daily ward visit only (8% of all daily ward visit reports). Conclusion: This study reconfirms that doctors are the main source for reports of serious and unknown adverse drug events in hospitalized patients. However, patients themselves seem to report more adverse reactions to new drugs (during the daily ward visit). By focusing on patients using new drugs, the daily ward visit might become cost-effective. This needs to be explored in future studies. Received: 10 September 1998 / Accepted in revised form: 30 November 1998  相似文献   
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