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Several likely precursors of schizophrenia have been identified. These range from possibly causative features, such as exposure to perinatal insults, to features that are the effects of an underlying vulnerability, such as abnormal childhood behaviors. Unfortunately none of these precursors is specific enough to be used in identifying individuals for targeted preventive treatment. A more useful strategy is to combine risk factors for psychotic disorders in a population seeking help for psychiatric problems. Thus, individuals who are possibly prodromal are identified. Research into this group has found high rates of onset of psychotic disorders, particularly schizophrenia, within a short time frame. Preliminary treatment trials suggest that symptoms can be reduced and psychosis onset possibly delayed or averted.  相似文献   
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OBJECTIVES: Patients with hematologic malignancies are frequently in need of major cardiac operations. Previous reports suggest an increased risk for perioperative complications in these immunodeficient patients. METHODS: Patients diagnosed with any type of hematologic malignancy who underwent open-heart surgery at our institution between 7/1996 and 6/2002 were identified. Their hospital charts were reviewed; demographics, perioperative data and outcomes were recorded. RESULTS: There were 24 patients (20 men, 4 women); mean age was 68+/-13 years (range 31-84 years). Ten patients had chronic lymphocytic leukemia, seven non-Hodgkin lymphomas, three multiple myeloma and one Hodgkin's disease, chronic myelocytic leukemia, hairy cell leukemia and cutaneous T-cell lymphoma each. The mean pre-operative duration of the hematologic disease was 6.6 years. Twenty-two patients underwent coronary artery bypass grafting (with valve replacement in three patients) and two patients had isolated valve replacement. There was one in-hospital death (4.1%). Twelve patients (50%) had a minor or major complication. Seven reoperations were required-five during the same admission (one for mediastinal bleeding, one for an expanding femoral pseudoaneurysm, one for acute cholecystitis and two for IACD/pacer insertion) and two within 30 days (one for deep sternal wound infection and one for leg wound infection). Mean post-operative stay was 8.2+/-5.8 days and mean ICU stay was 1.6+/-1.1 days. There were three late deaths-two were due to progression of the hematologic disease. The 3-year actuarial survival was 83%. CONCLUSIONS: Cardiac operations can be performed with acceptable mortality but significant morbidity rates in patients with hematologic malignancies. Bleeding and infectious complications are most frequently seen and usually lead to reoperations. These findings warrant caution during patient selection.  相似文献   
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Background: The authors conducted a double-blind, randomized, controlled trial to determine whether the use of sevoflurane in children undergoing anesthesia and surgery results in a higher incidence of postoperative maladaptive behavioral changes as compared with halothane.

Methods: Children and their parents (n = 102) were randomly assigned to either a halothane group (n = 50) or a sevoflurane group (n = 52). The intraoperative anesthetic protocol was strictly controlled, and the postoperative analgesic consumption and pain levels were recorded. The effect of the group assignment on emergence status and maladaptive postoperative behavioral changes was assessed both by validated psychological measures and physiologic instruments (actigraphy) on postoperative days 1-7. Anxiety of the parent and child was also assessed, as was the child's postoperative recovery (Recovery Inventory).

Results: There were no group differences in preoperative state anxiety, postoperative analgesic requirements, postoperative pain, or the incidence of emergence delirium (P = not significant). Two-way repeated-measures analysis of variance showed no group differences in the incidence of postoperative maladaptive behaviors (F4,72 = 0.60, P = 0.701) or actigraphic variables such as percent sleep, number of night awakenings, and night awakenings that lasted for more than 5 min (P = not significant).  相似文献   

65.
OBJECTIVE: There are currently no studies that have investigated dietary supplement use in the chronic renal insufficiency (CRI) population. The objectives of this study were to determine the prevalence of dietary supplement use in a sample of adults with CRI and to examine whether the prevalence of dietary supplement use was higher in the earlier stages of CRI. DESIGN AND SETTING: Cross-sectional survey conducted at an outpatient nephrology clinic. PATIENTS: Adults (n = 100) with varying degrees of CRI. INTERVENTION: Interview-administered questionnaire. MAIN OUTCOME MEASURES: The questionnaire contained questions related to the use of dietary supplements, attitudes, and beliefs about dietary supplements, as well as medical and demographic data including gender, age, body weight, smoking status, concurrent chronic conditions, prescribed medications, serum creatinine, estimated glomerular filtration rate (GFR), etiology of CRI, income, and education level. RESULTS: The prevalence of dietary supplement use was 45%, with the most frequent use occurring in subjects with a mild to moderate degree of renal insufficiency. There were no significant differences in gender, age, body mass index, smoking status, number of concurrent chronic conditions, number of prescribed medications, income, or education level between supplement users and supplement nonusers. Further analysis of dietary supplement use showed that the number of supplements used ranged from 1 to 5 or more supplements per day, with an overall total of 36 different supplements. Dietary supplement users were significantly more concerned with their health than were supplement nonusers. The most frequent sources of supplement information were physicians and printed material; however, 75% of the dietary supplement users desired further information about their dietary supplements. CONCLUSION: This is the first study to investigate the use of dietary supplements in adults with CRI, and it provides valuable information for health care professionals regarding the dietary supplement use of their patients with CRI.  相似文献   
66.
Tumour cells may express urokinase type plasminogen activator (u-PA). This may influence the invasive properties of the cells but has seldom been implicated in production of a systemic bleeding state. Two patients are described in whom severe bleeding occurred in association with disseminated malignancies. Thrombin generation was little disturbed and platelet numbers were insufficient to account for the bleeding. Florid plasmin generation was evident in the circulation and the fibrinolytic inhibitor tranexamic acid controlled the bleeding well. Free active u-PA was demonstrated in the circulation and u-PA antigen on the malignant cells which invaded the marrow of one of the patients. Tumour cell u-PA may occasionally be responsible for a bleeding state.  相似文献   
67.
Background: Intervention trials with self-selected participants have shown that mailed stage-targeted print materials can increase participation in physical activity in the short term. We examined the effects of a mailed stage-targeted print intervention designed to promote physical activity, in a random sample of adults living in a regional city.Method: Participants (n = 462, 40–60 years of age) were randomly allocated to an intervention in - 227) or control group (n - 235). Measures included validated 2-week physical activity recall and stage of motivational readiness for physical activity. The intervention consisted of a single mailing of a letter and full-color stage-targeted booklets (specific to precontemplation, contemplation, preparation, and action/maintenance) 1 week postbaseline. Follow-up interviews were conducted at 2 and 6 months postbaseline.Results: After 2 months, participants in the intervention group were significantly More likely to meet the current American College of Sports Medicine/Centers for Disease Control and Prevention recommendation for sufficient physical activity than those in the control group (adjusted odds ratio [OR] - 2.40; 95% confidence interval [CI] = 1.44–3.99). After 6 months, intervention participants who reported receiving and reading the intervention materials were significantly more likely to be meeting the sufficient physical activity criterion compared with the control group (adjusted OR = 2.03; 95% Cl = 1.16–3.56).Conclusions: The stage-targeted print intervention was effective in promoting short-term increases in physical activity and was most effective for participants who recognized and used the materials. This low-cost, generalizable intervention has demonstrated potential as a practical population-based physical activity promotion strategy. Further research is required before widespread dissemination would be justified, as additional strategies may be required to ensure sustained change. This project was supported by a National Heart Foundation of Australia Research Project Grant. David Crawford was supported by a Nutrition Research fellowship from the National Heart Foundation.  相似文献   
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The purpose of this study was to examine the effect of first metatarsophalangeal arthrodesis on the sagittal plane orientation of the first ray and the medial longitudinal arch. Lateral weightbearing radiographs of 48 patients (54 feet) having undergone the procedure were retrospectively reviewed. Patients were separated into three groups based on their preoperative diagnosis: hallux rigidus, hallux valgus, or rheumatoid forefoot deformity. First metatarsal declination, talometatarsal, talar declination, calcaneal inclination, and talocalcaneal angles were measured on pre- and postoperative radiographs. Multivariate analysis of variance determined that there was a significant postoperative change (p < .001) in angular measurements, particularly in the first metatarsal declination, talometatarsal, and talocalcaneal angles. There was also a significant difference (p < .01) in the angular measurements between the hallux rigidus group and the other two groups. However, the amount of change from pre- to postoperatively did not vary significantly between the groups. A calculation of Pearson correlation coefficients found no significant correlation between the hallux dorsiflexion angle and changes in angular measurements. The radiographic changes found in this study support Hicks' windlass model: fixed dorsiflexion of the hallux causes plantarflexion of the first ray and an increase in the medial longitudinal arch.  相似文献   
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