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171.
Streptokinase has been immobilized by covalent coupling to nylon. Subcutaneous implantation of the immobilized streptokinase into rabbits resulted in a three-fold increase in their blood clotting time, which was maintained for 150 days. The immobilized streptokinase lost little if any activity over this period and no evidence of antibody formation was found. Removal of the implanted nylon-streptokinase caused a return to normal clotting times within a few days. The preliminary results demonstrate a potential usefulness of immobilized streptokinase in the treatment of thrombotic occlusive disorders as well as in the prevention of such diseases. 相似文献
172.
Professor C. Kaplan MSC MB CH.B FRC.PATH 《International journal of clinical practice》1976,30(11-12):208-211
173.
A comparison of the effects of extracellular and intracellular thirst stimuli on plasma levels of angiotensin II was made in rats. The administration of polyethylene glycol and isoproterenol elicited a strong drinking response and resulted in a significant increase in plasma angiotensin II. There was a significant correlation between the volume of water intake and plasma angiotensin II levels following the injection of polyethylene glycol but not following isoproterenol. Drinking was also elicited by the administration of hypertonic saline but there was no increase in plasma angiotensin II. The results suggest that endogenously released angiotensin II contributes to extracellular thirst but not to intracellular thirst. 相似文献
174.
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176.
Hendler I Goldenberg RL Mercer BM Iams JD Meis PJ Moawad AH MacPherson CA Caritis SN Miodovnik M Menard KM Thurnau GR Sorokin Y 《American journal of obstetrics and gynecology》2005,192(3):882-886
OBJECTIVE: The purpose of this study was to evaluate the relationship between prepregnancy maternal body mass index and spontaneous preterm birth and indicated preterm birth. STUDY DESIGN: This was a secondary analysis of the Maternal-Fetal Medicine Units Network, Preterm Prediction study. Patients were classified into categories that were based on their body mass index. Rates of indicated and spontaneous preterm birth were compared. RESULTS: Five hundred ninety-seven (20.5%) of 2910 women were obese. Obese women had fewer spontaneous preterm births at < 37 weeks of gestation (6.2% vs 11.2%; P < .001) and at < 34 weeks of gestation (1.5% vs 3.5%; P = .012). Women with a body mass index of < 19 kg/m2 had 16.6% spontaneous preterm birth, with a body mass index of 19 to 24.9 kg/m 2 had 11.3% spontaneous preterm birth, with a body mass index of 25 to 29.9 kg/m2 had 8.1% spontaneous preterm birth, with a body mass index of 30 to 34.9 kg/m2 had 7.1% spontaneous preterm birth, and with a body mass index of > or = 35 kg/m2 had 5.2% spontaneous preterm birth (P < .0001). Indicated delivery was responsible for an increasing proportion of preterm births with increasing body mass index (P = .001). Obese women had lower rates of cervical length < 25 mm (5% vs 8%; P = .012). Multivariable regression analysis confirmed a lower rate of spontaneous preterm birth in obese gravid women (odds ratio, 0.57; 95% CI, 0.39-0.83; P = .003). CONCLUSION: Obesity before pregnancy is associated with a lower rate of spontaneous preterm birth. 相似文献
177.
Optimal athletic performance depends on proper function of many organs, including the blood. This is underscored by the focus of endurance athletes on increased hemoglobin through training at altitude or exogenous erythropoietin. Several other aspects of the hematologic system can also affect or be influenced by physical activity. In this article, the authors briefly discuss inherited abnormalities of the blood that can manifest themselves in athletes. We then discuss the effects of exercise on the blood, and acquired abnormalities of blood cells or coagulation parameters that occur in athletes, and that can influence performance or cause other symptoms. 相似文献
178.
Normal values and within-subject variability of cardiac I-123 MIBG scintigraphy in healthy individuals: Implications for clinical studies 总被引:3,自引:0,他引:3
G.?Aernout?SomsenEmail author Hein?J.?Verberne Eric?Fleury Alberto?Righetti 《Journal of nuclear cardiology》2004,11(2):126-133
BACKGROUND: Although several myocardial iodine 123 metaiodobenzylguanidine (MIBG) indices are increasingly used to detect alterations in myocardial sympathetic activity in various forms of cardiac pathology, published measurements of normal values and within-subject variability are lacking. METHODS AND RESULTS: Twenty-five healthy volunteers underwent planar and single photon emission computed tomography (SPECT) imaging. Heart-mediastinum ratio (H/M) and myocardial washout were calculated from planar images comparing three different methods for the assessment of myocardial activity: (1) global region over the myocardium (cavity included), (2) global region over the myocardium (cavity excluded), and (3) fixed small myocardial region. Segmental (relative) uptake and washout were assessed by SPECT. For all MIBG indices, the interindividual variation was the lowest for methods 1 and 2. In SPECT this variation was low for relative segmental uptake compared with washout. In 9 subjects a second MIBG scintigraphy was performed after 3 months. The within-subject variability of H/M and washout assessed by planar methods 1 and 2 was 5%, whereas it was approximately 9% for planar method 3. For relative segmental uptake from SPECT, this variability was 5%. CONCLUSION: MIBG H/M (planar) and relative segmental uptake (SPECT) show a low interindividual and within-subject variability. This enables the detection of small (regional) variations in myocardial sympathetic nervous function, especially to monitor the effect of therapeutic interventions in patients with various cardiac diseases. 相似文献
179.
Randomized clinical trial of intraoperative autotransfusion in surgery for abdominal aortic aneurysm 总被引:2,自引:0,他引:2
Mercer KG Spark JI Berridge DC Kent PJ Scott DJ 《The British journal of surgery》2004,91(11):1443-1448
BACKGROUND: Perioperative homologous blood transfusion (HBT) is associated with adverse reactions and risks transmission of infection. It has also been implicated as an immunosuppressive agent. Intraoperative autotransfusion (IAT) is a potential method of autologous transfusion. METHODS: This was a single-centre randomized clinical trial of IAT in surgery for abdominal aortic aneurysm. Forty patients were randomized to IAT and 41 underwent surgery with HBT only. Patients in both groups received HBT to maintain haemoglobin levels above 8 g/dl. Transfusion requirements, and incidence of systemic inflammatory response syndrome (SIRS) and infection, were compared. RESULTS: Significantly fewer patients in the IAT group required HBT (21 versus 31; P = 0.038) and the median blood requirement per patient was 2 units lower (P = 0.012). There was a higher incidence of chest infection (12 versus four patients; P = 0.049) and SIRS (20 versus nine patients; P = 0.020) in the HBT group. Risk of SIRS was related to aortic cross-clamp time in the IAT group only. CONCLUSION: Use of autotransfusion effectively reduced the need for HBT and was associated with a reduced incidence of postoperative SIRS and infective complications. 相似文献
180.
Urological manifestations of Down syndrome 总被引:1,自引:0,他引:1
Mercer ES Broecker B Smith EA Kirsch AJ Scherz HC A Massad C 《The Journal of urology》2004,171(3):1250-1253
PURPOSE: We identified the urological anomalies seen in patients with Down syndrome. MATERIALS AND METHODS: We reviewed the literature on Down syndrome and its associated genitourinary pathology. RESULTS: Associated defects have been reported throughout the genitourinary tract. The most common renal anomalies seen are renal hypoplasia, obstructive uropathy and glomerular microcysts. Decreased creatinine clearance has also been noted. Developmental anomalies, such as megaureter and vesicoureteral reflux, have been reported. Dysfunctional voiding and urinary retention have been found in these patients. Posterior urethral valves and hypospadias have also been seen. The testicular abnormalities most frequently reported are cryptorchidism, testicular cancer and infertility. CONCLUSIONS: Improved understanding and identification of the various urological anomalies associated with Down syndrome will aid in the care of these patients. In addition, an awareness of perioperative issues will further facilitate a smooth clinical course. 相似文献