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1.
Non-invasive tear break-up time (NITBUT) has been proposed as a measure of tear film integrity which is superior to the more commonly used tear break-up time (TBUT), since it does not alter the volume or the physicochemical properties of the tear layer by the addition of fluorescein. We measured NITBUT by measuring the time taken for distortions or discontinuities to appear in the reflected image of a grid pattern which covered about 80 per cent of the corneal surface. NITBUT measures were made 100 times on seven Hong Kong Chinese subjects with up to 20 consecutive measures being made on a single day. We also measured NITBUT on one occasion on an unselected population of 52 Hong Kong Chinese subjects. NITBUT shows a skewed distribution in all subjects, with many shorter values and some extremely long values. There are statistically significant variations in NITBUT from day to day, and from subject to subject. The group of 52 subjects also had a skewed NITBUT distribution with many short values and some very long values. The arithmetic mean does not adequately represent NITBUT data, either for individual subjects or for this group of subjects. As many as five to eight measures may be necessary to gain a stable estimate of the NITBUT and stability of the measure is improved if extreme values are omitted. We recommend the use of nonparametric statistics to compare NITBUT values from day to day in or between subjects. 相似文献
2.
The progesterone production of the granulosa cells of the cumulus oocyte complex correlates very well with the cleavagepotential of embryos in an IVF system. The method is simpleand can be easily performed by any laboratory associated withIVF. Furthermore, high intratubal progesterone levels in theimmediate post-ovulatory period are probably important in prolongingthe intra-ampullary residence of the oocyte or embryo untilthe uterine endometnum is optimal for implantation. 相似文献
3.
T. N. RAMUTHAGA M. s. BORNMAN M. F. MAHOMED D. BOOMKER A. S. GREEF H. H. CREWE-BROWN S. REIF 《International journal of andrology》1994,17(1):9-12
Swabbing the urethrae of men has been the traditional approach for collecting specimens for detection of Chlamydia trachomatis . Recently, however, urine testing using enzyme immunoassay has yielded promising results. A total of 105 patients attending the Andrology Clinic at Ga Rankuwa Hospital, Medunsa were included in the study. These patients were asymptomatic and had no urethral discharge. Three endo-urethral swabs and first-catch urine were collected fiom each patient. The urethral swabs were used for enzyme immunoassay (EIA) (IDEIA 111), tissue culture and direct immonufluorescent antibody (DFA) test (IMAGEN) to detect C. trachomatis . In addition about 15–30 ml of first-catch urine, or urine collected at least 2h after the previous micturition, was collected for each patient for EIA testing. Fifteen (14.3%) of 105 patients were positive on urethral swab EIA, in comparison with the DFA test in which 14 (13.3%) were positive. Eight (7.8%) were positive in tissue culture. Urine EIA was positive in 17 (16.2%) patients, of whom five (4.8%) were positive in urine EIA only. All EIA positive urines were confirmed by DFA. We recommend that first-catch urine or urine collected at least 2h after the previous micturition in infertile males may be considered a suitable alternative to urethral swab for chlamydial diagnosis because it is noninvasive and nontraumatic. 相似文献
4.
Albertini-Yagi CS Oliveira RC Vieira JE Negri EM de Oliveira LR Saldiva PH Lorenzi-Filho G 《Respiratory physiology & neurobiology》2005,145(1):101-110
The study objectives were to compare in vitro transportability and physical properties of respiratory mucus, obtained invasively by direct collection (DC) right after endotracheal intubation and non-invasively by sputum induction with 3% hypertonic saline solution inhalation (SI) 24 h before the anesthesia. Twenty-two patients with no pulmonary disease scheduled for elective abdominal surgical procedures were studied. The parameters analyzed and the main results are as follows. (1) Transportability by cilia (MCT), SI was higher than DC (0.94+/-0.25 and 0.62+/-0.25; P<0.001). There was a significant correlation between the two methods and DC could be estimated by: DC=0.21+(0.44 SI) (r=0.44; P<0.001). (2) Transportability by cough (CC), SI was higher than DC (68.23+/-32.1 and 33.58+/-19.04 mm; P=0.002). (3) Contact angle (CA), SI was lower than DC (10+/-3 degrees and 22+/-14 degrees ; P=0.025). (4) Rheological properties (no significant difference obtained between SI and DC). These results indicated that SI changes mucus physical properties and transportability in non-expectorators. 相似文献
5.
Bischoff FZ Sinacori MK Dang DD Marquez-Do D Horne C Lewis DE Simpson JL 《Human reproduction update》2002,8(6):493-500
Both intact fetal cells as well as cell-free fetal DNA are present in the maternal circulation and can be recovered for non-invasive prenatal genetic diagnosis. Although methods for enrichment and isolation of rare intact fetal cells have been challenging, diagnosis of fetal chromosomal aneuploidy including trisomy 21 in first- and second-trimester pregnancies has been achieved with a 50-75% detection rate. Similarly, cell-free fetal DNA can be reliably recovered from maternal plasma and assessed by quantitative PCR to detect fetal trisomy 21 and paternally derived single gene mutations. Real-time PCR assays are robust in detecting low-level fetal DNA concentrations, with sensitivity of approximately 95-100% and specificity near 100%. Comparing intact fetal cell versus cell-free fetal DNA methods for non-invasive prenatal screening for fetal chromosomal aneuploidy reveals that the latter is at least four times more sensitive. These preliminary results do not support a relationship between frequency of intact fetal cells and concentration of cell-free fetal DNA. The above results imply that the concentration of fetal DNA in maternal plasma may not be dependent on circulating intact fetal cells but rather be a product of growth and cellular turnover during embryonic or fetal development. 相似文献
6.
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
7.
P Morice S Camatte A Rey D Atallah C Lhommé P Pautier C Pomel J-F Coté C Haie-Meder P Duvillard D Castaigne 《Annals of oncology》2003,14(4):592-598
BACKGROUND: The aim of this study was to determine the prognostic factors for patients with advanced stage, low malignant potential ovarian tumour (LMPOT). PATIENTS AND METHODS: A retrospective review of 80 patients with serous LMPOT and peritoneal implants treated at or referred to our institution was carried out. RESULTS: Sixty-five patients had non-invasive implants. Fifteen patients had invasive implants. Twenty-nine patients had stage II and 51 patients had stage III disease. Three patients died of evolutive invasive disease and four of complications of treatment. The only prognostic factor of progression to 'evolutive invasive disease' is the pathologic subtype of peritoneal implants. The 5-year rates of evolutive invasive disease in patients with non-invasive implants and invasive implants were 2% and 31%, respectively (P <0.002). CONCLUSIONS: In this series, the only prognostic factor for patients with advanced stage borderline tumour is the type of peritoneal implant. More patients died of the treatment's complications than of the disease itself. The patients' prognosis with non-invasive implants seems to be excellent, and conservative management could be discussed in younger patients. 相似文献
8.
目的研究垂体腺瘤(pituitary adenoma)中细胞粘附分子(CD44)的表达,探讨CD44蛋白在垂体腺瘤侵袭性生长中的意义.方法用免疫组化(SP)的方法检测38例垂体腺瘤中CD44s、CD44v5蛋白的表达.结果20例侵袭性垂体腺瘤中CD44s、CD44v5阳性率分别为75%、35%.18例非侵袭性垂体腺瘤中CD44s、CD44v5阳性率分别为27.8%、22.2%.CD44s在侵袭性垂体腺瘤中表达的阳性率明显高于非侵袭性垂体腺瘤,其差异具有显著性(P<0.01),CD44v5在侵袭性垂体腺瘤中和非侵袭性垂体腺瘤中的表达率均较低,无显著性差异(P>0.05).结论CD44s在侵袭性垂体腺瘤中呈高表达,与垂体腺瘤的侵袭性生长有关,在垂体腺瘤的侵袭性生长过程中起重要作用.CD44v5在垂体腺瘤中的表达较低,与垂体腺瘤生长方式无关. 相似文献
9.
无创正压通气治疗的护理 总被引:5,自引:0,他引:5
通过17例呼吸衰竭患者应用无创正压通气(NIPPV)的临床观察与护理,结合治疗前后血气参数值的对比分析,总结出以下护理体会:心理护理,选择合适的体位及鼻(面)罩是应用NIPPV的前提;防止漏气和面部皮肤压迫性损伤,保持呼吸道通畅,密切观察患者通气效果及呼吸机性能是应用NIPPV的护理重点;密切观察患者病情变化,进行氧疗,协助患者排痰是NIPPV治疗后的护理措施。 相似文献
10.
无创正压通气和支气管灌洗术在哮喘重度急性发作伴有呼吸衰竭治疗中的价值 总被引:2,自引:1,他引:1
目的 探讨无创正压通气结合支气管灌洗术在哮喘重度急性发作伴有呼吸衰竭治疗中的价值。方法 将23例哮喘重度急性发作伴有呼吸衰竭患者分为2组,常规治疗组(A组)和常规治疗+无创正压通气+支气管灌洗组(B组),比较两组的疗效。结果A组有9例最后接受有创通气治疗(90%),共4例死亡(40%);B组仅3例(23.1%)最后接受有创通气治疗,共3例死亡(23.1%)。结论 哮喘重度急性发作伴有呼吸衰竭患者先试行无创正压通气结合支气管灌洗术治疗有可能避免有创机械通气。 相似文献