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41.
Griffin  JH; Mosher  DF; Zimmerman  TS; Kleiss  AJ 《Blood》1982,60(1):261-264
Activated protein C is a potent anticoagulant and profibrinolytic enzyme that can be derived from the vitamin-K-dependent serine protease zymogen, protein C, by the action of thrombin. Protein C antigen concentration was determined in plasmas from normals (n = 40) and from 38 patients with intravascular coagulation as evidenced by positive FDP (greater than micrograms/ml). Plasma protein C was 4 micrograms/ml in normals and was significantly depressed (less than 2 SD below the mean of normals) in 19 of the 38 patients. Of 15 patients with suspected intravascular coagulation but normal FDP, protein C was decreased in 5 individuals; 3 of these 5 patients had liver disease. Based on these results, we suggest that extensive activation of the coagulation system in vivo causes a significant consumption of protein C, presumably due to its activation by thrombin and subsequent clearance.  相似文献   
42.
Kickler  TS; Herman  JH; Furihata  K; Kunicki  TJ; Aster  RH 《Blood》1988,71(4):894-898
Baka is a platelet alloantigen whose putative allele, Bakb, has not been identified previously. By using a serum, "Har," obtained from a patient with posttransfusion purpura, we describe the platelet alloantigen Bakb. The Har serum reacted with an NP-40-extractable platelet membrane protein of 142 kd with mobility similar to platelet glycoprotein IIb alpha. We found that the antigen recognized by the Har serum is inherited in an autosomal dominant mode with an apparent gene frequency of .39. Chi-square analysis of observed and expected phenotype frequencies indicated that serum Har recognizes Bakb, the anticipated allele of Baka. Our findings provide new evidence for polymorphism of glycoprotein IIb and for the association of posttransfusion purpura with alloimmunization to determinants on this glycoprotein.  相似文献   
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Saba  HI; Saba  SR; Dent  J; Ruggeri  ZM; Zimmerman  TS 《Blood》1985,66(2):282-286
Type IIB von Willebrand disease is characterized by enhanced ristocetin- induced platelet aggregation and absence of large von Willebrand factor multimers from plasma. An alteration of the von Willebrand factor molecule resulting in increased reactivity with platelets appears to be the basis for these abnormalities. We have now identified a new variant of type IIB von Willebrand disease in a family in which the four affected members also have chronic thrombocytopenia, in vivo platelet aggregate formation, and spontaneous platelet aggregation in vitro. In spite of repeatedly prolonged bleeding times and persistent thrombocytopenia, their bleeding diathesis is only moderate.  相似文献   
45.
To evaluate the reliability of phosphorus-31 magnetic resonance (MR) spectroscopy in the assessment of acute testicular ischemia, vascular integrity, and spermatogenesis, the authors studied in vivo canine and primate testicles grouped as follows: group 1 testes (n = 8), in situ canine controls; group 2 (n = 11), canine testes subjected to warm ischemia; group 3, canine (n = 4) and primate (n = 4) testicles from hormone-treated animals. Group 1 control testicles showed high monophosphoester (MP) levels; low levels of inorganic phosphate (Pi), phosphodiester (PD), and phosphocreatine; and high levels of adenosine triphosphate (ATP). Group 2 testes revealed a time-dependent decay of MP/Pi ratios (from 2.1 to 0.70). Regeneration of ATP was noted in the acute reperfusion period. After 6 weeks of pituitary gonadotropin suppression, group 3 testes showed a significant decrease (P less than .05) in MP/PD ratios from a control level of 2.6 +/- 0.3 and a decrease in the MP/beta-ATP ratio from 2.4 +/- 0.1 to 1.8 +/- 0.3. P-31 MR spectroscopy appears to be a potential method for noninvasively assessing testicular ischemic injury and the metabolic integrity of spermatogenesis.  相似文献   
46.
In a prospective hospital based study, during the period from Jan 95 to Dec 96, 3100 consecutively delivered live newborns were studied for the incidence of low birth weight neonates and to evaluate the associated risk factors. One thousand fourteen newborns were classified as low birth weight babies. The incidence expressed per 1000 live births was 327 (32.7%). Of these, 815 (80.4%) were small for gestational age neonates and 199 (19.6%) were preterm neonates. Five hundred seventy small for gestational age neonates (70%) were weighing between 2001 to 2500 gms. Mothers belonging to the age group of 19-25 years delivered the maximum number of low birth weight babies (618/1014) and of these 82.8% were small for gestational age neonates. There were 48 neonates with low birth weight born to mothers below the age of 18 years. Primiparous mothers were found to contribute higher number of low birth weight neonates (414/1014). Spacing as a factor did not show any major difference. Two hundred sixty two low birth weight neonates were born to mothers with significant obstetrical problems such as pregnancy induced hypertension, bad obstetrical history and premature rupture of membranes. The incidence of 32.7% of low birth weight babies is high enough to ring alarm bells.  相似文献   
47.
Low serum albumin and low serum cholesterol levels are among the most consistent predictors of mortality in patients with end-stage renal disease (ESRD) undergoing hemodialysis. Hypoalbuminemia is often interpreted as a marker of poor nutrition, but serum albumin and cholesterol levels can also be low as part of a cytokine-mediated acute-phase reaction to acute or chronic inflammation. Here we report the results from a 900-day prospective study designed to determine whether tumor necrosis factor-alfa (TNF-alpha) and interleukin-6 (IL-6) predict serum albumin and cholesterol levels and mortality in a group of 90 ambulatory, adult hemodialysis patients with no acute infection, hospitalization or surgery, and no known acquired immunodeficiency syndrome (AIDS), malignancy, or liver disease. Measurable levels of TNF-alpha and/or IL-6 were found in 89 of 90 patients. Significant relationships were found between TNF-alpha and IL-6 and the degree of hypoalbuminemia and dyslipoproteinemia. IL-6 was the strongest predictor of mortality in univariate and multivariate analysis, followed by age, albumin level, and body mass index (BMI). Although the cause of hypercytokinemia was not addressed in this study, the data support the view that hypoalbuminemia and hypocholesterolemia are negative acute-phase responses to inflammatory stimuli. These results suggest that efforts to identify the nature of the stimuli for cytokine production and to lower cytokine levels in hemodialysis patients might be effective in improving the survival of patients undergoing hemodialysis.  相似文献   
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