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21.
22.
JS Pooni Dr DWL Hukins PF Harris RC Hilton KE Davies 《Surgical and radiologic anatomy : SRA》1986,8(3):175-182
Posterior and anterior heights, cross-sectional area and shape were measured for all the intervertebral discs in four spines from elderly human cadavers. Disc height was a minimum at the T4-5 level; thoracic discs were less wedge-shaped than those in the cervical and lumbar regions. Cross-sectional area increased from the cranial to caudal extremity; at the L5-S1 level the nucleus pulposus occupied a high proportion of this area. Cervical discs tended to have an elliptical cross-sectional shape, thoracic discs were more circular and lumbar discs tended to have an elliptical cross-section which was flattened or re-entrant posteriorly. This shape distribution was quantified by defining a shape index which had a maximum value of 1 for a circular cross-section. Orientations of the reinforcing fibres in the outer lamellae of the anterior annulus fibrosus were measured from 27 discs by X-ray diffraction. For these measurements, C3-4, T7-8 and L2-3 were chosen as representative of cervical, thoracic and lumbar discs. The fibre tilt, with respect to the axis of the spine, was significantly less in the cervical discs (at 65 degrees) than in the thoracic and lumbar discs (about 70 degrees). These findings are interpreted in relation to differing functional requirements and possible mechanisms of failure in the cervical, thoracic and lumbar regions of the spine in the light of current knowledge on the biomechanics of the intervertebral disc. 相似文献
23.
The mean maximum nuclear diameter (Dmax) in 21 cases of non-Hodgkin's lymphoma (NHL) has been determined, using the Reichert-Jung (Kontron) MOP-AMO3 user-controlled image analyser. Nuclear diameters of high-grade malignancy NHL were found to be considerably greater than those of low-grade malignancy lymphomas, although there was some overlap of their ranges. These findings confirm objectively subjective estimates of nuclear size in NHL. The relative usefulness of the user-controlled (interactive) image analyser for the measurement of nuclei in tissue sections is compared with that of a fully automatic machine. 相似文献
24.
Preliminary report of an ultrasonography and colour Doppler uterine score to predict uterine receptivity in an in-vitro fertilization programme 总被引:1,自引:4,他引:1
Salle B; Bied-Damon V; Benchaib M; Desperes S; Gaucherand P; Rudigoz RC 《Human reproduction (Oxford, England)》1998,13(6):1669-1673
A total of 96 women undergoing in-vitro fertilization (IVF) treatment were
examined by transvaginal ultrasonography with colour and pulsed Doppler
ultrasound on the 22nd day of the menstrual cycle preceding IVF. We
assessed endometrial thickness, endometrial morphology, myometrial
echogenicity, subendometrial vascularization, the uterine artery
pulsatility index, protodiastolic notch and end diastolic blood flow in
order to define a uterine score which could be correlated with the
pregnancy rate. The overall pregnancy rate was 30.2%, and there was no
difference between the pregnant and non-pregnant groups with regard to any
of the ultrasonographic and Doppler parameters when examined separately.
However, the uterine score was significantly higher in the pregnant group
(15.9 +/- 2.81 versus 12.7 +/- 5.3, P = 0.002; t-test). No pregnancy
occurred if the score was between 0 and 10. With a score of 11-15 there was
a 34.7% chance of pregnancy, and scores >16 had a 42% chance of
pregnancy. In conclusion, individual ultrasonographic and Doppler
parameters are not of sufficient accuracy to predict uterine receptivity.
The uterine score calculated prior to IVF cycles appears to be a useful
predictor of implantation.
相似文献
25.
ReSllm6 Objectif Nos studes Precedentes out montrd une panne fonCtion de la greffe pulmonaire traitde Prdalablementper perfusion forcde retrograde et un stockage d froid inns ~. L' etude Prdsente a pour but de determiner l' effet de ~ surlefiot mngUin du poumon trait4 Prdalablement per perfusion retrograde forcde et un stockage d froid. met~. 12poumons donneurs canins out ate trait4s per perfusion r4tFograde de solution UW. Chez 6 animaux du grouch A, 250ng furent injectes dans l' artrdre… 相似文献
26.
RAJVIR BHALWAR HS SANDHU RC AHUJA GK SINGH RP MISRA 《Medical Journal Armed Forces India》1994,50(3):175-180
A population based hybrid design combining element of cohort and cross-sectional approach was used to develop a simple clinical algorithm to predict individual probability of developing hypertension (systolic BP > 140 mm Hg and/or diastolic BP > 90 mmHg). 3615 soldiers initially normotensive at the time of induction into high altitude, were studied by systematic random sampling. Multiple logistic regression analysis showed a high significant association between hypertension and age, body mass index (BMI), tobacco smoking and alcohol consumption. Using the constant/coefficient values obtained from the logistic model and the receiver operating characteristics (ROC) curve analysis, the following predictive rule was developed – To the age in years, add (BMIx 3.86); also add 5.53 if he is a smoker; and add 19.81 if he consumes alcohol. If the total exceeds 142, the individual is at high risk of developing hypertension. This algorithm carries a sensitivity of 68.2% and specificity of 78.5%.KEY WORDS: Hypertension, High altitude 相似文献
27.
The effects of a gestational exposure of 80 rats Wistar EPM-1 to nicotine and undernutrition was examined. The weight and histological alterations on the liver and lungs was evaluated on the rats and their offspring. A significantly lower weight gain, including liver and lung weight, was observed in nicotine exposed groups. There was no alteration of the placental weight. Decidual necrosis and hepatic congestion was frequent in the rats. Lung emphysema was found in the neonates. 相似文献
28.
A 3 year old Turkish girl is described who was suffering from major histocompatibility complex (MHC) class II deficiency syndrome, which is characterised by the lack of expression of HLA class II antigens on mononuclear cells. The presence of HLA class II genes was demonstrable at the DNA level. Combined immunodeficiency was indicated by hypogammaglobulinaemia and the absence of delayed type hypersensitivity on skin testing. Further, she was unable to produce specific antibodies towards foreign antigens and suffered from recurrent pulmonary, gastrointestinal, and septic infections from the third month of life. The clinical course was complicated by a Coombs test positive haemolytic anaemia due to the production of autoantibodies against the rhesus "e' antigen, a non-glycosylated protein antigen. Haemolysis could be controlled by oral steroid treatment. This case is of interest as it shows that despite the absence of HLA class II antigens and combined immunodeficiency autoimmune reactions with production of specific autoantibodies directed to protein antigens are possible. 相似文献
29.
Hemingway H Crook AM Dawson JR Edelman J Edmondson S Feder G Kopelman P Leatham E Magee P Parsons L Timmis AD Wood A 《Journal of public health medicine》1999,21(4):421-429
BACKGROUND: Previous studies investigating the appropriateness of invasive management of coronary disease had not reported the internal consistency of their ratings and may now be out of date. The aim of this study was to measure the influence of clinical factors on contemporary ratings of the appropriateness of coronary angiography, percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass graft (CABG) in the Appropriateness of Coronary Revascularisation (ACRE) study. METHODS: The Delphi-RAND technique was used, in which an expert panel (four cardiologists, three cardiothoracic surgeons, a general physician and a general practitioner), meeting in 1995, rated mutually exclusive indications (n = 2178 for angiography, n = 995 for PTCA and n = 984 for CABG). The main outcome measures were the appropriateness category (inappropriate, uncertain or appropriate) for each of the three procedures and treatment preference. RESULTS: For revascularization, the strongest determinant of inappropriateness was coronary anatomy. The odds ratio (OR) for inappropriate PTCA was 10.6 (95 per cent confidence interval (CI) 4.8-23.5) for the effect of left main stem or three-vessel disease versus single-vessel disease, and for CABG it was 0.06 (95 per cent CI 0.03-0.15). The number of diseased vessels was strongly related to preference for medical, PTCA or CABG treatment (p for linear trend <0.001). Mild versus severe anginal symptoms were associated with inappropriate angiography (OR 2.0 (95 per cent CI 0.9-9.8), although this effect was stronger when only the cardiologists' ratings were considered (OR 10.1 (95 per cent CI 2.4-42.6)). CONCLUSION: These are the first UK ratings of appropriateness covering all three procedures. The associations with clinical factors provide evidence of the internal consistency of these ratings. Prospective validation of these ratings against clinical outcomes is under way in the ACRE study. 相似文献
30.
The purpose of the authors in this article was to evaluate the effects of supplementing maternal milk with two different caloric formulas on the growth of premature newborns until they reached 40 weeks of post-conceptional age. Seventy premature infants weighing < 1750g at birth were randomized: 35 adequate for gestational age (AGA) and 35 small for gestational age received maternal milk and either a special preterm formula or a modified formula. Anthropometric measurements and clinical evaluations were used to determine the nutritional status and the postnatal growth of these infants, who were analyzed in six different moments: at maximum weight loss, at return to birth weight, at definite weight gain, when exclusively fed with formula, at 2000g, and when they reached 40 weeks of post-conceptional age. The AGA premature newborns on preterm formula had greater daily weight gain, cephalic circumference increase and growth. The SGA premature newborns on preterm formula had greater daily weight gain and cephalic circumference increase observed from the third week of life onward. The AGA premature newborns on modified formula had less weight gain and smaller increments in the cephalic circumference. The SGA premature on modified formula had the worst anthropometric results. The preterm formula was more efficient than the modified formula in promoting postnatal growth of AGA and SGA premature infants. We believe that, due to their special characteristics, SGA premature should receive individualized nutritional caloric planning 相似文献