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991.
Portal vein measurement by ultrasonography in patients with long-standing cystic fibrosis: preliminary observations 总被引:1,自引:0,他引:1
S Kumari-Subaiya J Gorvoy G Phillips P Ross M M Riddelsberger 《Journal of pediatric gastroenterology and nutrition》1987,6(1):71-78
Adult cystic fibrosis (CF) patients are increasingly diagnosed with hepatic cirrhosis, cholecystitis, and cholelithiasis. A continuing diagnostic problem is the early detection of cirrhosis prior to diffuse liver involvement. Sonography has been used in evaluating the pancreas, gallbladder, liver, and spleen in cystic fibrosis patients. We used a real-time mechanical sector scanner to study the portal veins in adult CF patients randomly selected from our CF population and correlated the portal vein diameters with liver function studies. A measurement greater than 12 mm was interpreted as a probable sign of portal hypertension. Of 21 patients studied, 14 had portal veins that measured greater than 12 mm, and 12 patients had (although not necessarily at the time of the exam) elevated serum alkaline phosphatase levels. Three patients had associated splenomegaly and thrombocytopenia, and 10 patients also exhibited cholelithiasis and abnormal gallbladders on sonography. Initial results indicate that portal vein measurement may be a sensitive indicator of early portal hypertension. Sonography may, thus, isolate patients at high risk for possible future complications. Serial sonograms can be performed easily in evaluating the progress of liver disease. 相似文献
992.
Blood samples (4 ml) for plasma arginine vasopressin (AVP) measurements were obtained at 3- to 4-hour intervals under basal conditions for 1-2 days from 5 date-bred ewes with chronic maternal and fetal vascular catheters. In addition, 6 chronically catheterized ewes were infused with 2 liters of 0.45% NaCl over 30 min. Fetal and maternal blood samples were obtained before and after the infusion period for measurement of plasma osmolality and AVP concentrations. In the first study, maternal and fetal plasma AVP levels correlated significantly (p less than 0.01, by linear regression analysis) under basal conditions. In the second study, baseline mean (+/- SEM) plasma osmolality was similar for pregnant ewes and fetuses (303 +/- 3.1 and 302 +/- 2.4 mosm/kg, respectively). There was a significant (each, p less than 0.01 by paired t test) decrease from baseline in maternal and fetal osmolality during the 30 min after completion of the hypotonic saline (to 292 +/- 4.7 and 296 +/- 2.4 mosm/kg, respectively). Fetal plasma AVP levels decreased 17 +/- 6% by 30 min following the completion of water loading (1.7 +/- 0.07 to 1.4 +/- 0.16 microU/ml; p less than 0.05). Maternal plasma AVP levels decreased 16 +/- 4% by 30 min after completion of infusion (1.6 +/- 0.14 to 1.38 +/- 0.6 microU/ml; p less than 0.05). These results indicate that maternal and fetal plasma AVP levels correlate under basal conditions and that maternal water loading, which significantly decreases fetal plasma osmolality, significantly suppresses fetal plasma AVP concentrations. 相似文献
993.
994.
A Technique for Enrichment of Motile Spermatozoa from Oligozoospermic and Asthenozoospermic Patients
Peter C. S. Leung MD † Ross V. Hyne PhD Gary N. Clarke MSc # Ian Johnston MGO FRACOG # 《The Australian & New Zealand journal of obstetrics & gynaecology》1984,24(3):210-212
Summary: A system for rapid selection of normal motile spermatozoa from poor semen samples is described. Analysis of the selected samples shows that there are significant improvements in the percentage motility, velocity and morphology. The final spermatozoa suspension of 0,5 ml is sufficient for the purpose of intrauterine AIH and IVF. 相似文献
995.
Effect of temperature and length of storage on serum-stimulated and serum-independent lipolytic activities in human milk 总被引:1,自引:0,他引:1
R M Clark K H Hundrieser S Ross P B Brown 《Journal of pediatric gastroenterology and nutrition》1984,3(4):567-570
Milk was collected from five mothers. Upon collection, serum-stimulated and serum-independent lipolytic activities were determined. The milk samples were aliquoted and stored at 25, 4, -20, and -70 degrees C. After storage for 3, 6, 12, and 24 h, serum-stimulated and -independent activities were again determined and compared with the initial activities. Storage at 25 degrees C resulted in a significant (p less than 0.05) decrease in lipolytic activity. Serum-stimulated activity decreased 83.4% and serum-independent activity decreased 66.9% over the 24-h period. Storage at 4 degrees C resulted in a significant (p less than 0.05) decrease of 22.6% in serum-stimulated activity and a 7.2% decrease in serum-independent activity. No significant changes were observed in milk stored for 24 h at -20 and -70 degrees C. Milk was stored at -20 and -70 degrees C for an additional 1, 2, and 4 weeks. Serum-stimulated lipolysis did not change significantly over the 4-week period. Serum-independent lipolysis increased significantly (p less than 0.05) with storage time. Storage at -20 degrees C resulted in an increase of 20% and storage at -70 degrees C resulted in an increase of 36% over the 4 weeks. 相似文献
996.
997.
Coulter CL Pestell RG Ross JT Salkeld MD James S Bennett HP McMillen IC 《Endocrine research》2002,28(4):625-629
In the sheep, there is a rapid increase in fetal adrenal growth and steroidogenesis during the last 10-15 days gestation. Recently, we have shown that infusion of POMC 1-77 increases fetal adrenal growth but does not significantly alter fetal plasma cortisol concentrations. Phosphorylation and inactivation of the pRB protein, which is required for progression into the DNA synthetic phase of the cell-cycle is conducted by a holoenzyme, for which cyclin D1 gene encodes the rate-limiting regulatory subunit. To further elucidate the mechanisms by which POMC 1-77 regulates adrenal growth, we therefore examined adrenal expression of the rate-limiting cell cycle protein, cyclin D1, from fetuses infused for 48 hr with POMC 1-77 (n = 6), POMC 1-49 or Saline (n = 6). There was no significant difference in the adrenal expression of cyclin D1 mRNA levels between POMC 1-77, 1-49 and saline infused fetuses. There was no significant correlation between cyclin D1 (4.0 Kb) and adrenal weight. In summary, these data do not demonstrate that the rate-limiting cell cycle protein, cyclin D1, is activated to stimulate adrenal growth following infusion of POMC 1-77 in the fetal sheep in late gestation. 相似文献
998.
999.
1000.
The 2001 Canadian recommendations for the management of hypertension: Part two--Therapy 总被引:1,自引:0,他引:1
McAlister FA Zarnke KB Campbell NR Feldman RD Levine M Mahon J Grover SA Lewanczuk R Leenen F Tobe S Lebel M Stone J Schiffrin EL Rabkin SW Ogilvie RI Larochelle P Jones C Honos G Fodor G Burgess E Hamet P Herman R Irvine J Culleton B Wright JM;Canadian Hypertension Recommendations Working Group 《The Canadian journal of cardiology》2002,18(6):625-641
OBJECTIVE: To provide updated, evidence-based recommendations for the therapy of hypertension in adults. OPTIONS: For patients with hypertension, a number of antihypertensive agents may control blood pressure. Randomized trials evaluating first-line therapy with thiazides, beta-adrenergic antagonists, angiotensin-converting enzyme inhibitors, calcium channel blockers, alpha-blockers, centrally acting agents or angiotensin II receptor antagonists were reviewed. OUTCOMES: The health outcomes that were considered were changes in blood pressure, cardiovascular morbidity, and cardiovascular and/or all-cause mortality rates. Economic outcomes were not considered due to insufficient evidence. EVIDENCE: MEDLINE was searched for the period March 1999 to October 2001 to identify studies not included in the 2000 revision of the Canadian Recommendations for the Management of Hypertension. Reference lists were scanned, experts were polled, and the personal files of the subgroup members and authors were used to identify other published studies. All relevant articles were reviewed and appraised, using prespecified levels of evidence, by content experts and methodological experts. VALUES: A high value was placed on the avoidance of cardiovascular morbidity and mortality. BENEFITS, HARMS AND COSTS: Various antihypertensive agents reduce the blood pressure of patients with sustained hypertension. In certain settings, and for specific classes of drugs, blood-pressure lowering has been associated with reduced cardiovascular morbidity and/or mortality. RECOMMENDATIONS: The present document contains detailed recommendations pertaining to treatment thresholds, target blood pressures, and choice of agents in various settings in patients with hypertension. The main changes from the 2000 Recommendations are the addition of a section on the treatment of hypertension in patients with diabetes mellitus, the amalgamation of the previous sections on treatment of hypertension in the young and old into one section, increased emphasis on the role of combination therapies over repeated trials of single agents and expansion of the section on the treatment of hypertension after stroke. Implicit in the recommendations for therapy is the principle that treatment for an individual patient should take into consideration global cardiovascular risk, the presence and/or absence of target organ damage, and comorbidities. VALIDATION: All recommendations were graded according to strength of the evidence and voted on by the Canadian Hypertension Recommendations Working Group. Individuals with potential conflicts of interest relative to any specific recommendation were excluded from voting on that recommendation. Only those recommendations achieving high levels of consensus are reported here. These guidelines will continue to be updated annually. 相似文献