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41.
S Badve RP A''Hern AM Ward RR Millis SE Pinder IO Ellis BA Gusterson JP Sloane 《Canadian Metallurgical Quarterly》1998,29(9):915-923
OBJECTIVE: To identify the independent and differential diagnostic and symptom correlates of suicidal ideation and suicide attempts and determine whether there are gender- and age-specific diagnostic profiles. METHOD: The relationships between suicidal ideation, suicide attempts, and psychiatric disorders were examined among 1,285 randomly selected children and adolescents, aged 9 to 17 years, of whom 42 had attempted suicide and 67 had expressed suicidal ideation only. Youths and their parents were interviewed as part of the Methods for the Epidemiology of Child and Adolescent Mental Disorders (MECA) Study, using the Diagnostic Interview Schedule for Children Version 2.3 (DISC-2.3). RESULTS: Logistic regression analyses indicated that mood, anxiety, and substance abuse/dependence disorders independently increased the risk of suicide attempts, after controlling for sociodemographic characteristics. There was no significant independent contribution of disruptive disorders to suicide attempts, although its association with suicidal ideation was significant. Substance abuse/dependence independently differentiated suicide attempters from ideators. Noncriterion symptoms that remained significant predictors of suicide risk, after adjusting for psychiatric disorder, included panic attacks and aggressiveness. Perfectionism did not significantly increase suicide risk after adjusting for psychiatric disorder. The association of specific disorders and noncriterion symptoms with suicidality varied as a function of gender and age. CONCLUSION: A monolithic diagnostic risk profile for suicidality, ignoring gender- and age-specific risks, is inadequate. The contribution of substance abuse/dependence in the escalation from suicidal thoughts to suicide attempts is underscored. 相似文献
42.
AJ Evans SE Pinder DR Snead AR Wilson IO Ellis CW Elston 《Canadian Metallurgical Quarterly》1997,75(4):542-544
This study was carried out to assess the frequency of ductal carcinoma in situ (DCIS) occurring within and surrounding grade 3 invasive tumours and the effect of its detection on size and nodal stage of invasive carcinomas at mammographic detection. Grade 3 tumours with either no associated DCIS or DCIS only within the invasive component were significantly larger in size than tumours with surrounding DCIS (P < 0.02) and were less likely to be under or equal to 10 mm in size (0% or 13% vs 30% respectively, P < 0.02). Tumours with mammographic calcification were more likely to be less than or equal to 10 mm in size than non-calcific tumours (32% vs 11% respectively, P < 0.05). This was because of the high frequency of tumours less than or equal to 10 mm in size in the linear/branching calcification group. Tumours showing calcification without a mass also appear to be a group with good prognostic features, with a mean size of 13 mm, 33% being 10 mm or less in size and only 17% being node positive. We have found that the presence of surrounding DCIS enables earlier detection of grade 3 invasive carcinomas because of the presence of mammographically visible calcification. Detection of calcification suggestive of DCIS should remain an important part of mammographic screening. 相似文献
43.
A 56-year-old woman was admitted to our hospital with the chief complaint of left back pain. We detected left pleural effusion on chest X-ray and performed chest drainage. No malignant cells were detected in the effusion. Chest CT demonstrated a tumor shadow over the left diaphragm and left pleural effusion 6 months later. She underwent en bloc resection of the tumor and left diaphragm. Histological evaluation revealed malignant fibrous histiocytoma (MFH). Recurrent tumors were found in the abdomen 8 months after the operation, and she underwent resection of the abdominal recurrent tumors. Histological evaluation of the recurrent tumors also showed MFH. The patient died 28 months after the first operation. 相似文献
44.
The authors consider the class of conformal antennas consisting of bounded smooth closed curves in two dimensions and determine the surface field which maximizes power radiated in angular sector. The problem is cast as one of optimal control with the control set consisting of the surface current, constrained to have energy bounded by some constant, and the cost functional is taken to be the far field power radiated in an angular sector. A constructive algorithm is presented for approximating both the optimal value of the cost functional and the surface current which produce this optimal value. Bothte andtm polarizations are considered. 相似文献
45.
3D Graphitic Foams Derived from Chloroaluminate Anion Intercalation for Ultrafast Aluminum‐Ion Battery
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46.
SF Khuri N Healey H MacGregor MR Barnard IO Szymanski V Birjiniuk AD Michelson DR Gagnon CR Valeri 《Canadian Metallurgical Quarterly》1999,117(1):172-83; discussion 183-4
OBJECTIVE: The aim of the study was to compare the clinical effects and hemostatic efficiency of transfusions of platelets preserved in the frozen state for as long as 2 years with transfusions of platelets preserved in the conventional manner for as long as 5 days in patients undergoing cardiopulmonary bypass. METHODS: Seventy-three patients were prospectively randomly assigned to receive transfusions of cryopreserved or liquid-preserved platelets. Nonsurgical blood loss was measured during and after the operation. Bleeding time, hematologic variables, and the bleeding time site shed blood were assayed before cardiopulmonary bypass and at 30 minutes and 2, 4, and 24 hours after transfusion. In vitro platelet function tests were conducted on platelets obtained from healthy volunteers. RESULTS: No adverse sequelae of the transfusions were observed. Blood loss and the need for postoperative blood product transfusions were lower in the group receiving cryopreserved platelets. Lower posttransfusion platelet increments and a tendency toward decreased platelet survival were observed in patients receiving cryopreserved platelets. Hematocrit and plasma fibrinogen were significantly higher in this group, and the duration of intubation was shorter. In vitro, cryopreserved platelets demonstrated less aggregation, lower pH, and decreased response to hypotonic stress but generated more procoagulant activity and thromboxane. CONCLUSIONS: (1) Cryopreserved platelet transfusions are superior to liquid-preserved platelets in reducing blood loss and the need for blood product transfusions after cardiopulmonary bypass. (2) The reduction in blood loss in the patients receiving cryopreserved platelet transfusions after cardiopulmonary bypass probably reflects improved in vivo hemostatic function of cryopreserved platelets. (3) Some in vitro measures of platelet quality (aggregation, pH, hypotonic stress) may not reflect in vivo quality of platelet transfusions after cardiopulmonary bypass, whereas other in vitro measures (platelet procoagulant activity and thromboxane) do. 相似文献
47.
48.
WL Patton JK Willmann AM Lutz IO Rencken CA Gooding 《Canadian Metallurgical Quarterly》1999,29(2):95-99
Perforation, a severe complication of necrotizing enterocolitis (NEC), has a high mortality rate. Recently, we presented a new technique for evaluation of NEC: measuring the CT attenuation coefficient of urine after oral administration of iohexol. We present three cases of neonates with NEC who demonstrated serial increases in urine CT attenuation coefficients, all of whom subsequently deteriorated clinically and radiographically. Surgery in all three cases confirmed severe necrosis and/or perforation. These three cases suggest that the CT attenuation coefficient of urine after oral administration of iohexol may be a more sensitive indicator of NEC severity, progression, and perforation than clinical evaluation and radiography. More investigation is necessary, but eventually, this noninvasive technique may be able to decrease morbidity and mortality by predicting the need for surgical intervention or more aggressive medical management of NEC before perforation occurs. 相似文献
49.
Abstract In October 1988 the authors were invited to lecture at the University of Warsaw. During the visit they also gave an advisory lecture to the Computer Centre of Polish National Television on strategies for low cost computer graphics. This article discusses the strategies presented during the lecture. Several possible generic strategies are examined below, and although they are discussed in the context of the Polish Television, most of the discussion would be valid and appropriate for any large television company. Indeed, with the advent of the satellite and cable television, even western commercial television stations will be inclined to develop policies for the introduction of low‐cost computer graphics into their productions. 相似文献
50.