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61.
In this paper we describe an approach to the study of time use data that focuses on relatively infrequent activities as well as the contexts in which the activities take place. To illustrate the method, we present several examples from a secondary analysis of the Multinational Comparative Time-Budget data, based on over 25,000, 24-hour, time use diaries collected in 12 countries during 1965 through 1966. Activities that represent a small fraction of the overall time budget of a population may nevertheless yield valuable insights into a culture or group. Analyses of such mundane events as doing the laundry, transporting children, and taking a walk indicate marked differences among the countries surveyed in terms of frequencies, durations, by whom, and with whom these activities were typically performed. In the future, time use studies can be expected to contribute to the understanding of mental disorders in natural contexts. In contrasting specific diagnostic groups with normal subjects, analyses of specific activities (e.g., personal care, social interaction) or contexts (e.g., alone vs. with others, at home vs. away) may be particularly relevant. Strategies that combine continuous recording (diary) with repeated, instantaneous experience-sampling methods are likely to be the most useful in such studies of mental disorders.  相似文献   
62.
Summary In a phase I study the anthrapyrazole biantrazole (Warner-Lambert Company) was given to 41 patients with tumour refractory to existing therapy. The drug was given i.v. weekly for 3 weeks, with a 3-week interval between courses. At the 1st week a full pharmacokinetic study was performed, and at weeks 2 and 3, blood samples were taken at 1 and 6 h following treatment to check for drug accumulation. Biantrazole pharmacokinetics were linear with respect to the AUC (r=0.924) over the full range of doses studied (4–36 mg/m2) but exhibited large inter-patient variations at each dose level. Elimination was triphasic, comprising two rapid early phases and a long terminal half-life (mean, 14.1±7.8 h). There was no evidence of drug accumulation over the 3-week treatment period. Approximately 12% of the parent drug was excreted unchanged in the urine together with two non-circulating, more water-soluble metabolites. Biantrazole was well tolerated but did cause moderate emesis at doses of >18 mg/m2 and mild alopecia. The dose-limiting side effect was leucopenia, with no other major toxicity being observed. One patient developed biventricular failure that was not clearly related to biantrazole administration. On the present schedule, the recommended dose of biantrazole is 24 mg/m2. No response were seen in this patient population. Authors: on behalf of the EORTC Early Clinical Trials Group and the CRC Phase I/II Trials Committee  相似文献   
63.
The quantity and localization of two lactose-binding lectins with molecular weights of 31,000 and 14,500 in human colorectal carcinoma tissue specimens obtained by surgical resection have been studied using specific polyclonal antibodies. Electrophoretic separation and blotting of detergent extracts of tumor tissues (48 specimens), followed by the binding of an antibody that recognizes both of these lectins, demonstrated that the contents of Mr 31,000 and 14,500 lectins vary from one specimen to another. The Mr 31,000 lectin content was higher in tumor specimens classified as Dukes' stage D than in those from other stages. A significant correlation was found between Mr 31,000 lectin levels and the levels of carcinoembryonic antigen in the patients' sera at the time of surgery. Immunohistochemical staining with antibodies specific for each lectin was performed with 20 colon carcinoma tissues and 5 colonic adenoma tissues. The results showed that the Mr 31,000 lectin localizes in the cytoplasm of colorectal carcinoma cells and normal epithelial cells, whereas antibody binding to Mr 14,500 lectin is observed in a limited number of carcinoma specimens and is mainly associated with luminal surfaces and secretory products. Adenoma cells were reactive with Mr 14,500 anti-lectin antibody at their luminal surfaces or cytoplasms, but they did not stain with Mr 31,000 anti-lectin antibody. These results suggest that a correlation exists among the level of the Mr 31,000 lectin, the serum level of carcinoembryonic antigen, and the stage of progression of colorectal carcinomas.  相似文献   
64.
Significant numbers of mast cells have been demonstrated histologically around the periphery of the invasive rat mammary adenocarcinoma 13672NF. The number of mast cells at microfoci along the tumour:host tissue junction was significantly greater than that found in normal mammary tissues, and few mast cells were detected within the tumour itself. Mast cell degranulation, often associated with disruption and lysis of the connective tissue matrix, was a common feature in later stages of tumour proliferation. When soluble products derived from purified rat peritoneal mast cells were added to monolayer cultures of rat stromal fibroblasts or tumour cells they stimulated a significant increase in total collagenase production, and the mast cell products were also capable of activating the latent collagenases thus produced. Histological examination indicated that degradation of local collagenous matrix was a common feature of mast cell degranulation, an observation possibly explained by the release of mast cell enzymes and/or the potential of this cell to modulate the expression of collagenolytic activity by surrounding cells. These observations suggest that, at least in some tumours, mast cells contribute to the connective tissue breakdown commonly associated with tumour invasiveness and metastatic spread.  相似文献   
65.
The correlation between metastatic potential and the organization of microtubules and microfilaments in nine cell lines and clones derived from the 13762NF rat mammary adenocarcinoma was investigated using immunofluorescence techniques. Cell sizes and morphologies of cell clones isolated from the locally growing 13762NF tumor were heterogeneous; those derived from spontaneous metastases were more homogeneous. The organization of microtubules was similar in cells of various 13762NF lines and clones, and differences could not be detected with the techniques employed. The organization of microfilaments was very heterogeneous within some clones but homogeneous within others. Correlations between microfilament organization and origin of a cell line or clone or its metastatic potential were not found in this tumor system.  相似文献   
66.
67.
Children with autism spectrum disorder (ASD) exhibit characteristic cognitive and behavioral differences, but no systematic pattern of neuroanatomical differences has been consistently found. Recent neurodevelopmental models posit an abnormal early surge in subcortical white matter growth in at least some autistic children, perhaps normalizing by adulthood, but other studies report subcortical white matter deficits. To investigate the profile of these alterations in 3D, we mapped brain volumetric differences using a relatively new method, tensor‐based morphometry. 3D T1‐weighted brain MRIs of 24 male children with ASD (age: 9.5 years ± 3.2 SD) and 26 age‐matched healthy controls (age: 10.3 ± 2.4 SD) were fluidly registered to match a common anatomical template. Autistic children had significantly enlarged frontal lobes (by 3.6% on the left and 5.1% on the right), and all other lobes of the brain were enlarged significantly, or at trend level. By analyzing the applied deformations statistically point‐by‐point, we detected significant gray matter volume deficits in bilateral parietal, left temporal and left occipital lobes (P = 0.038, corrected), trend‐level cerebral white matter volume excesses, and volume deficits in the cerebellar vermis, adjacent to volume excesses in other cerebellar regions. This profile of excesses and deficits in adjacent regions may (1) indicate impaired neuronal connectivity, resulting from aberrant myelination and/or an inflammatory process, and (2) help to understand inconsistent findings of regional brain tissue excesses and deficits in autism. Hum Brain Mapp, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
68.
The medical records of all patients born between 1 September, 2000, and 31 August, 2002, and undergoing the first stage of Norwood reconstruction, were retrospectively reviewed for details of the perioperative course. We found 99 consecutive patients who met the criterions for inclusion. Hospital mortality for the entire cohort was 15.2%, but was 7.3%, with 4 of 55 dying, in the setting of a "standard" risk profile, as opposed to 25.0% for those with a "high" risk profile, 11 of 44 patients dying in this group. Extracorporeal membrane oxygenation was utilized in 7 patients, with 6 deaths. Median postoperative length of stay in the hospital was 14 days, with a range from 2 to 85 days, and stay in the cardiac intensive care unit was 11 days, with a range from 2 to 85 days. Delayed sternal closure was performed in 18.2%, with a median of 1 day until closure, with a range from zero to 5 days. Excluding isolated delayed sternal closure, and cannulation and decannulation for extracorporeal support, 24 patients underwent 33 cardiothoracic reoperations, including exploration for bleeding in 12, diaphragmatic plication in 4; shunt revision in 4, and other procedures in 13. The median duration of total mechanical ventilation was 4.0 days, with a range from 0.7 to 80.5 days. Excluding those who died, the median total duration of mechanical ventilation was 3.8 days, with a range from 0.9 to 46.3 days. Reintubation for cardiorespiratory failure or upper airway obstruction was performed in 31 patients. Postoperative electroencephalographic and/or clinical seizures occurred in 13 patients, with 7 discharged on anti-convulsant medications. Postoperative renal failure, defined as a level of creatinine greater than 1.5 mg/dl, was present in 13 patients. Eleven had significant thrombocytopenia, with fewer than 20,000 platelets per microl, and injury to the vocal cords was identified in eight patients. Risk factors for longer length of stay included lower Apgar scores, preoperative intubation, early reoperations, reintubation and sepsis, but not weight at birth, genetic syndromes, the specific surgeon, or the duration of surgery.Although mortality rates after the first stage of reconstruction continue to fall, the course in the intensive care unit is remarkable for significant morbidity, especially involving the cardiac, pulmonary and central nervous systems. These patients utilize significant resources during the first hospitalization. Further studies are necessary to stratify the risks faced by patients with hypoplasia of the left heart in whom the first stage of Norwood reconstruction is planned, to determine methods to reduce perioperative morbidity, and to determine the long-term implications of short-term complications, such as diaphragmatic paresis, injury to the vocal cords, prolonged mechanical ventilation, and postoperative seizures.  相似文献   
69.
The explosion in neuroscientific knowledge has profound implications for education, and we advocate the establishment of the new discipline of 'pedagogical neuroscience' designed to combine psychological, medical, and educational perspectives. We propose that specific learning disabilities provide the crucible in which the discipline may be forged, illustrating the scope by consideration of developmental dyslexia. Current approaches have failed to establish consensus on fundamental issues such as theoretical causes, diagnostic methods, and treatment strategies. We argue that these difficulties arise from diagnosis via behavioural or cognitive symptoms, even though they may arise from diverse causes. Rather than an inconvenience, variability of secondary symptoms within and across learning disabilities can inform both diagnosis and treatment. We illustrate how brain-based theories lead to radical restructuring of diagnostic methods and propose that there is an urgent need to develop genetic and brain-based diagnostic methods designed to lead to individually-appropriate remediation and treatment methods.  相似文献   
70.
Prism adaptation, in which the participant adapts to prismatic glasses that deflect vision laterally, is a specific test of cerebellar function. Fourteen dyslexic children (mean age 13.5 years); 14 children with developmental coordination disorder (DCD): 6 of whom had comorbid dyslexia; and 12 control children matched for age and IQ underwent prism adaptation (assessed by clay throwing accuracy to a 16.7 degrees visual displacement). All 8 DCD children, 5 of the 6 children with comorbid DCD and dyslexia and 10 of the 14 dyslexic children showed an impaired rate of adaptation, thereby providing strong evidence of impaired cerebellar function in DCD and developmental dyslexia. Taken together with other emerging evidence of overlap between developmental disorders, these findings highlight the importance of complementing research on the individual disorders with research on the commonalities between the disorders.  相似文献   
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