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71.
Establishment of predictive variables associated with testicular sperm retrieval in men with non-obstructive azoospermia 总被引:2,自引:0,他引:2
Although testicular biopsy for sperm extraction is a procedure with a potential for complications, sperm retrieval is successful in 30-70% of patients with non-obstructive azoospermia. In order to predict the probability of retrieving at least one testicular spermatozoon we conducted a prospective study of a set of variables in 40 patients with non-obstructive azoospermia. Using the receiver operating characteristic curves, we determined the probability estimates of testicular volume, plasma follicle stimulating hormone (FSH) concentration, Johnsen score and visualization of testicular spermatids in discriminating between patients with successful and failed testicular sperm extraction. Visualization of testicular spermatids provided the best estimate of success of testicular sperm extraction. Of the factors studied using logistic-regression analysis (age, maternal and paternal age at birth, body mass index, luteinizing hormone, testosterone, FSH, testicular volume, the presence of testicular spermatids and Johnsen score), only the presence of spermatids and Johnsen score were independent variables able to predict the success of testicular sperm extraction. The visualization of the presence of spermatids gave a correct prediction of 77% and Johnsen score of 71%. The diagnostic model derived from these independent predictors when validated in 40 patients using the Jackknife technique gave a correct overall prediction of 87%. The probability of successful testicular sperm extraction in patients with non-obstructive azoospermia could be objectively predicted on the basis of simple histopathological criteria represented by the visualization of testicular spermatids and Johnsen score. 相似文献
72.
THOMAS PENZEL 《Journal of sleep research》1995,4(S1):15-20
SUMMARY Arterial blood pressure is influenced by sleep-related breathing disorders. As cardiovascular consequences can be diagnosed by an accurate recording and analysis of blood pressure, new recording methodologies and an approach to analysis are presented here. Invasive continuous blood pressure recording is the common reference for all methodologies. As blood pressure varies rapidly in parallel with sleep-related breathing disorders it is indispensible to record blood pressure continuously. To introduce non-invasive methodology the Finapres system was used during sleep studies; a validation study showed severe limitations. This study was followed by the validation of an improved system called Portapres, which is portable, has two finger cuffs and a hydrostatic height compensation.
Analysis of continuous blood pressure in patients with sleep apnoea is carried out to detect mechanisms which influence the cardiovascular risk. Spectrum analysis of systolic blood pressure showed two different major oscillations present in patients with obstructive sleep apnoea. One oscillation (<0.06 Hz) occurs in parallel with each apnoeic episode and the other oscillation (0.2-0.4 Hz) occurs in parallel with the obstructive efforts during each apnoea and in parallel with respiration during periods of snoring. These two oscillations were so specific that the use of non-invasive continuous blood pressure recording allowed an estimation of the extent of underlying breathing disorders, and assessment of cardiovascular risk in a patient with obstructive apnoea in terms of hypertension and on the basis of ambulatory monitoring. 相似文献
Analysis of continuous blood pressure in patients with sleep apnoea is carried out to detect mechanisms which influence the cardiovascular risk. Spectrum analysis of systolic blood pressure showed two different major oscillations present in patients with obstructive sleep apnoea. One oscillation (<0.06 Hz) occurs in parallel with each apnoeic episode and the other oscillation (0.2-0.4 Hz) occurs in parallel with the obstructive efforts during each apnoea and in parallel with respiration during periods of snoring. These two oscillations were so specific that the use of non-invasive continuous blood pressure recording allowed an estimation of the extent of underlying breathing disorders, and assessment of cardiovascular risk in a patient with obstructive apnoea in terms of hypertension and on the basis of ambulatory monitoring. 相似文献
73.
张丹 《中国卫生标准管理》2021,(6):95-98
目的探究肿瘤M2型丙酮酸激酶检测在结肠癌诊断中的临床价值。方法选取本院经病理诊断确诊为结肠癌的50例患者与结肠腺瘤的60例患者分别设为结肠癌组与结肠腺瘤组,选择90例健康人设为正常组,分别使用ELISA、化学发光法(CL)检测血浆M2-PK数值及癌胚抗原(CEA)水平。结果结肠癌组及Dukes C、D期肿瘤M2-PK水平与结肠腺瘤组、正常组及Dukes A、B期相比更高(P<0.05),肿瘤M2-PK结肠癌诊断敏感性与CEA相比更高。结论肿瘤M2型丙酮酸激酶检测在结肠癌诊断中具有较高的临床价值,且肿瘤M2-PK的敏感性高于CEA,与肿瘤分期之间具有十分密切的联系,能够有效应用于结肠癌的筛查与诊断工作当中。 相似文献
74.
Wojciech Nazar Katarzyna Plata-Nazar Katarzyna Sznurkowska Agnieszka Szlagatys-Sidorkiewicz 《Nutrients》2021,13(5)
Histamine intolerance is defined as a disequilibrium of accumulated histamine and the capacity for histamine degradation. This clinical term addresses a non-immunologically mediated pathology when histamine ingested with food is not particularly high, however its degradation is decreased. This paper aims to provide a narrative review on etiopathology, epidemiology, possible diagnostic algorithms and diagnostic challenges of histamine intolerance in children. The clinical picture of histamine intolerance in children is similar to that observed in adults apart from male predominance found in paediatric patients. Both in children and adults, a histamine-reduced diet is typically the treatment of choice. Diamine oxidase supplementation offers another treatment option. There is no symptom or test pathognomonic for histamine intolerance. Nevertheless, manifestations of chronic gastrointestinal symptoms, measurements of diamine oxidase deficits, positive results of histamine provocation tests and improvement in symptoms with histamine-reduced diet considerably increase the probability of histamine intolerance diagnosis. These factors have been included in the proposed diagnostic algorithm for histamine intolerance. In children histamine intolerance most likely co-occurs with allergies and bowel diseases, which creates an additional diagnostic challenge. As the evidence for children is poor further research is needed the determine epidemiology, validate diagnostic algorithms and establish possible treatment options regarding histamine intolerance. 相似文献
75.
Kyohei Itamura Arthur Wu Elisa Illing Jonathan Ting Thomas Higgins 《JMIR Public Health and Surveillance》2021,7(1)
BackgroundReal-time polymerase chain reaction using nasopharyngeal swabs is currently the most widely used diagnostic test for SARS-CoV-2 detection. However, false negatives and the sensitivity of this mode of testing have posed challenges in the accurate estimation of the prevalence of SARS-CoV-2 infection rates.ObjectiveThe purpose of this study was to evaluate whether technical and, therefore, correctable errors were being made with regard to nasopharyngeal swab procedures.MethodsWe searched a web-based video database (YouTube) for videos demonstrating SARS-CoV-2 nasopharyngeal swab tests, posted from January 1 to May 15, 2020. Videos were rated by 3 blinded rhinologists for accuracy of swab angle and depth. The overall score for swab angle and swab depth for each nasopharyngeal swab demonstration video was determined based on the majority score with agreement between at least 2 of the 3 reviewers. We then comparatively evaluated video data collected from YouTube videos demonstrating the correct nasopharyngeal swab technique with data from videos demonstrating an incorrect nasopharyngeal swab technique. Multiple linear regression analysis with statistical significance set at P=.05 was performed to determine video data variables associated with the correct nasopharyngeal swab technique.ResultsIn all, 126 videos met the study inclusion and exclusion criteria. Of these, 52.3% (66/126) of all videos demonstrated the correct swab angle, and 46% (58/126) of the videos demonstrated an appropriate swab depth. Moreover, 45.2% (57/126) of the videos demonstrated both correct nasopharyngeal swab angle and appropriate depth, whereas 46.8% (59/126) of the videos demonstrated both incorrect nasopharyngeal swab angle and inappropriate depth. Videos with correct nasopharyngeal swab technique were associated with the swab operators identifying themselves as a medical professional or as an Ear, Nose, Throat–related medical professional. We also found an association between correct nasopharyngeal swab techniques and recency of video publication date (relative to May 15, 2020).ConclusionsOur findings show that over half of the videos documenting the nasopharyngeal swab test showed an incorrect technique, which could elevate false-negative test rates. Therefore, greater attention needs to be provided toward educating frontline health care workers who routinely perform nasopharyngeal swab procedures. 相似文献
76.
77.
Elizabeth Kunkel Peter Tanuseputro Amy Hsu Robert Talarico Julie Lapenskie Samantha Calder-Sprackman Daniel Kobewka 《Journal of the American Medical Directors Association》2021,22(4):901-906.e4
ObjectivesTo investigate the association between rapid access to radiographs, blood tests, urine cultures, and intravenous (IV) therapy in a long-term care (LTC) home with resident transfers to the emergency department (ED).DesignRetrospective cohort study.Setting and Participants21,811 residents living in 162 LTC homes in Ontario, Canada.MethodsWe administered a survey to LTC homes to collect wait times for radiographs, basic blood tests, urine culture, and IV therapy. Rapid availability was defined as typically receiving test results within 1 or 2 days, or same-day IV therapy. We linked the survey results to administrative data and defined a cohort of residents living in survey-respondent homes between January and May 2017. We followed residents in the linked administrative databases for 6 months, until discharge, or death. Two physicians identified diagnostic codes for ED visits that were potentially preventable with rapid availability of each of the 4 resources. Multilevel logistic regression models estimated associations between potentially preventable ED visits and rapid diagnostic tests and intravenous access while controlling for demographic characteristics, illness severity, LTC home size, chain status, and physician availability.ResultsRapid blood tests, radiographs, urine culture, and IV therapy were available in 55%, 47%, 34%, and 45% of LTC homes, respectively. LTC homes that were part of multihome chains were less likely to have rapid access to the 4 resources. Of the 4736 residents (27%) who visited an ED during follow-up, individuals from homes with rapid access to radiographs (odds ratio 0.79, 95% confidence interval 0.66-0.97), urine culture (0.88, 0.72-1.08), blood tests (0.83, 0.69-1.00), and IV therapy (0.93, 0.70-1.23) tended to have fewer potentially preventable ED visits.Conclusions and ImplicationsRapid access to diagnostic testing and IV therapy in LTC reduced ED visits. Improving access to these resources may prevent ED visits and allow residents to stay home. 相似文献
78.
董海明 《中国医疗器械信息》2021,(1)
目的:研究关于核磁共振技术对膝关节损伤进行诊断的临床诊断效果和价值。方法:本文调查时间选择2019年1月~2020年1月,将在此期间到本院接受膝关节损伤治疗的35例患者作为研究对象,分别对所有患者选择采用核磁共振技术和CT诊断技术行膝关节损伤的诊断,并分析比较两种不同诊断方法诊断的效果和价值。结果:经过比较分析可以得出,应用核磁共振诊断技术对膝关节损伤进行诊断的准确率明显高于CT诊断手段,两组数据进行统计学分析比较,P<0.05,存在统计学差异性。结论:通过核磁共振技术对膝关节损伤进行诊断能够有效地提升诊断的准确率,可以实现对于各类损伤类型的诊断,可以及时地帮助患者提供相关的治疗依据。 相似文献
79.
高志民 《中国医疗器械信息》2021,(7):81-83
目的:探讨在乳腺微小癌诊断中联合应用超声弹性成像及数据系统(BI-RADS)分类的临床价值。方法:选择2018年3月~2019年3月本院接收的疑似乳腺微小癌的96例患者作为研究对象。均进行超声弹性成像检查、BI-RADS分类,以病理检查结果为诊断金标准,比较单项检查与联合检查的准确率、灵敏度、特异度。结果:数据显示,在96例疑似乳腺微小癌患者中,共80例患者经病理检查确诊为乳腺微小癌,同时乳腺钼靶联合超声检查的准确性、灵敏度均高于单项检测,数据之间的差异有统计学意义(P<0.05)。此外,单项与联合检测的特异度对比,差异无统计学意义(P>0.05)。结论:在乳腺微小癌诊断中联合应用超声弹性成像及BI-RADS分类检查,可有效提高诊断准确性及灵敏度,对早期疾病诊断、临床治疗具有重要意义。 相似文献
80.
Alice Ramondetta Simone Ribero Pietro Quaglino Paolo Broganelli 《Emerging infectious diseases》2021,27(1):281
Fluorescence-advanced videodermatoscopy is not a widespread diagnostic technique. Its application in dermatology can facilitate the diagnosis of diseases such as cutaneous larva migrans by enabling us to recognize the precise position of larva in vivo on the skin. Using this noninvasive technique, we detected a case of cutaneous larva migrans in a patient. 相似文献