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21.
22.
The present study provides an analysis of the effects of particular patterns of teacher respose to students' entries in dialogue journals. It extended on previous research related to teacher-student instructional discourse by concentrating on written, teacher-student interactions. Second grade children who were participating in a daily dialogue journal activity were randomly subjected to two types of response patterns by their teacher. The results show that a teacher's elaborative responses to student journal entries directly lead to increase written output by students coupled with a distinct process #ophigher order#cp orientation of student entries. 相似文献
23.
Adverse reactions to the preschool (fifth) dose of adsorbed diphtheria-pertussis-tetanus vaccine in Canadian children.
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D W Scheifele W Meekison M Grace L Barreto A O Carter L Mitchell J Farley 《Canadian Medical Association journal》1991,145(6):641-647
OBJECTIVE: To quantify accurately the rate of adverse reactions after the preschool (fifth) dose of adsorbed diphtheria toxoid-pertussis vaccine-tetanus toxoid (DPT) vaccine and to test the hypothesis that large local reactions are attributable to the diphtheria toxoid. DESIGN: Double-blind randomized controlled trial. SETTING: Suburban community public health unit. PARTICIPANTS: Healthy children 4 to 5 years of age with a history of having received four doses of adsorbed DPT vaccine. INTERVENTIONS: Subjects were given either the standard DPT vaccine (with 25 Lf units of diphtheria toxoid) or a modified DPT vaccine (with 10 Lf units of diphtheria toxoid). They were assessed 24 hours later by a nurse. Serum samples obtained before vaccination were tested for diphtheria and tetanus antitoxin levels by means of neutralization assay and enzyme-linked immunosorbent assay. MAIN OUTCOME MEASURES: Rates of large local reactions (an area of redness or swelling or both of 5 cm or greater) 24 hours after vaccination in the two groups. Relation between serum antitoxin levels before vaccination and the rate of large local reactions in each group. RESULTS: Of the 250 subjects enrolled 124 received the standard vaccine and 126 the modified one. Large local reactions occurred in 71% of the subjects receiving the standard vaccine and 52% of those receiving the modified one (p less than 0.01). In the former group large erythematous reactions occurred significantly more often in those with an elevated prevaccination diphtheria antitoxin level than in those without an elevated level; no relation was found between such reactions and the prevaccination tetanus antitoxin level. Reduced arm movement was evident in 45% of the children in the two groups. Few had systemic adverse reactions. CONCLUSIONS: Large local reactions occur frequently after the preschool administration of the DPT vaccine. These reactions are uncomfortable but not serious. They result in part from the large amount of diphtheria toxoid in the standard DPT vaccine. 相似文献
24.
Coexisting rheumatoid arthritis and ankylosing spondylitis 总被引:2,自引:0,他引:2
G H Fallet C G Barnes H Berry A G Mowat H Roux J Villiaumey 《The Journal of rheumatology》1987,14(6):1135-1138
Since the second publication by some of the present authors in which 10 patients with coexisting rheumatoid arthritis (RA) and ankylosing spondylitis (AS) were described, 7 new cases have been found. For accuracy, all cases of the original study still available were reexamined. Of the total of 17 cases, 13 were male and 4 female. All had positive tests for rheumatoid factor and 6 had subcutaneous nodules. The male predominance and the frequency of nodules are consistent with other publications. In addition, our study demonstrates the strong association of each of these 2 diseases with its genetic marker: the antigen HLA-DR4 was present in 8 of 12 cases tested and the antigen HLA-B27 was present in 16 of the 17 cases. The coexistence of these 2 classical rheumatological entities in the same patient appears to occur by chance and is probably often overlooked. 相似文献
25.
Actin-free Gc globulin: a rapidly assessed biomarker of organ dysfunction in acute liver failure and cirrhosis. 总被引:2,自引:0,他引:2
Charalambos G Antoniades Philip A Berry Matthew Bruce Timothy J S Cross Andrew J Portal Munther J Hussain William Bernal Julia A Wendon Diego Vergani 《Liver transplantation》2007,13(9):1254-1261
Reductions in serum levels of Gc globulin, a hepatically synthesized component of the extracellular actin scavenger system responsible for complexing circulating actin and attenuating intravascular microthrombus formation, are associated with poor outcome in acute liver failure. Clinically applicable assays of the important actin-free fraction (Af-Gc) have not been available until now. We measured actin-free Gc globulin levels with a novel, rapid assay in 61 cases of acute liver failure (ALF) and in 91 patients with cirrhosis (40 of whom were clinically unstable with extrahepatic organ dysfunction), and studied associations with liver dysfunction, extrahepatic organ dysfunction, indices of disseminated coagulation, and outcome. Reductions in Af-Gc levels mirrored hepatic dysfunction and organ dysfunction in both groups, and discriminated patients with poor prognosis from those with good prognosis in the ALF cohort. Levels were lowest in patients with ALF (10% of control values), but levels were also markedly reduced in both unstable (28%) and stable (44%) patients with cirrhosis. Associations with markers of disseminated intravascular coagulation were seen in both groups, most notably in the cirrhosis cohort, supporting a pathophysiological role for reduced Af-Gc in the evolution of organ dysfunction. In acetaminophen-induced ALF, Af-Gc identified patients with poor prognosis as well as did the Acute Physiology and Chronic Health Evaluation (APACHE II) score (area under the receiver operating characteristic curve, 0.7), and in cirrhosis, Af-Gc was an independent predictor of mortality by multifactorial analysis. In conclusion, the importance of Af-Gc reductions in the development of multiple organ dysfunction in ALF and cirrhosis is highlighted, probably resulting from reduced hepatic production and peripheral exhaustion of this arm of the extracellular actin scavenger system. 相似文献
26.
27.
P-glycoprotein (Pgp) is a plasma membrane protein that was first characterised in multidrug resistant cell lines. The occurrence of Pgp in clinical tumors has been widely studied. Recent investigations have begun to focus on the relationship between Pgp detection in tumors and treatment outcome. In several types of tumors, detection of Pgp correlates with poor response to chemotherapy and shorter survival. P-glycoprotein overexpression often occurs upon relapse from chemotherapy but may also occur at the time of diagnosis. Studies of experimental rat liver carcinogenesis have shown that Pgp expression increases in late stages of carcinogenesis, suggesting that Pgp may be involved in tumor progression. While some of the Pgp isoforms are known to transport hydrophobic chemotherapeutic drugs out of tumor cells, the biologic effects of Pgp overexpression in tumor cells are not fully understood, because the spectrum of substrates for Pgp-mediated transport has not been determined. In the rat liver carcinoma model, strong expression of Pgp is associated with a highly vascular stroma, suggesting that Pgp in tumor cells may affect the connective tissue stroma. The regulation of Pgp appears to be complex, and little is known about how it is up-regulated during carcinogenesis. Further studies of the role of Pgp in malignancy may contribute to our understanding of molecular mechanisms which underlie tumor progression. 相似文献
28.
Routine maternal serum alpha-fetoprotein (MSAFP) screening for neural tube defects is considered by many to be standard obstetrical care, and recently many have encouraged this test to screen for Trisomy-21 (Down's syndrome). We questioned whether, after a normal MSAFP screen, the risk of Trisomy-21 decreases enough to warrant modifying the recommended age for genetic amniocentesis for Down's syndrome. A logistic regression was developed which, using reported values for sensitivity and specificity for MSAFP detection of Trisomy-21 and assuming a constant threshold risk in opting for amniocentesis, indicates that genetic amniocentesis for Trisomy-21 may be deferred in some women who have a normal MSAFP screening. Sensitivity analysis of varying thresholds for a normal MSAFP demonstrates that a 37 year old woman with a median MSAFP level has the same risk for Trisomy-21 as an unscreened women who is 4.5 years younger. An abnormal MSAFP is useful in screening for neural tube defects and possibly for Trisomy-21. A normal MSAFP may allow for delaying the potentially risky amniocentesis in otherwise low-risk pregnancies. 相似文献
29.
Mallampati classification and laryngeal mask airway insertion 总被引:3,自引:0,他引:3
30.