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排序方式: 共有1742条查询结果,搜索用时 125 毫秒
991.
992.
LM Arnold SL McElroy DF Mutasim MM Dwight CL Lamerson EM Morris 《Canadian Metallurgical Quarterly》1998,59(10):509-514
BACKGROUND: Psychogenic excoriation, characterized by excessive scratching or picking of the skin, is not yet recognized as a symptom of a distinct DSM-IV disorder. The purpose of this study was to provide data regarding the demographics, phenomenology, course of illness, associated psychiatric comorbidity, and family history of subjects with psychogenic excoriation. METHOD: Thirty-four consecutive subjects were recruited from an outpatient dermatology practice and by advertisement. Subjects completed the Structured Clinical Interview for DSM-IV augmented with impulse control disorder modules, the Yale-Brown Obsessive Compulsive Scale, and a semistructured interview for family history, demographic data, and clinical features. RESULTS: Most subjects were women who described a mean age at onset of 38 years and a chronic course. Subjects excoriated multiple sites, most frequently the face. The behavior caused substantial distress and dysfunction. All 34 subjects met criteria for at least 1 comorbid psychiatric disorder, with a mood disorder the most common. Family histories were notable for depressive disorders and psychoactive substance use disorders. Most subjects experienced both mounting tension before excoriation and relief after excoriation as in impulse control disorders. A minority of subjects excoriated skin as part of obsessive-compulsive disorder. Body dysmorphic disorder with preoccupation about the skin's appearance precipitated excoriation in about a third of subjects. CONCLUSION: Psychogenic excoriation is chronic, involves multiple sites, and is associated with a high rate of psychiatric comorbidity. The behavior associated with the excoriation is heterogeneous and spans a compulsive-impulsive spectrum. Most subjects in this sample described features of an impulse control disorder. 相似文献
993.
994.
OBJECTIVE: To determine a reference range for the 75-g glucose tolerance test (GTT) in pregnancy using a group of women at low risk for gestational diabetes mellitus (GDM) and to determine the validity of this reference range by examining selected pregnancy outcomes for glucose-tolerant women with a 2-h result on the GTT up to 1.0 mmol/l below the diagnostic level for GDM compared with treated women with GDM. RESEARCH DESIGN AND METHODS: The reference range for the GTT was determined in 573 Caucasian women with an age <25 years and a BMI of <25 kg/m2. Selected pregnancy outcomes were compared between 272 treated women with GDM (diagnosed on the basis of a 2-h glucose level > or =8.0 mmol/l) and 308 women with a 2-h glucose level of 7.0-7.9 mmol/l. RESULTS: There was 95% confidence that at least 95% of all the fasting glucose levels are < or =5.1 mmol/l(92 mg/dl) and 95% confidence that at least 95% of all the 2-h glucose levels were < or =7.8 mmol/l (140 mg/dl). Treated women with GDM had a significantly reduced rate of large-for-gestational-age infants compared with glucose-tolerant women, without any increase in the rate of small-for-gestational-age infants or obstetric interventions. CONCLUSIONS: The reference range for the GTT in pregnancy should be determined on a low-risk population rather than on a total population. Consideration should be given to lowering the fasting glucose level to 5.0 mmol/l (90 mg/dl) and the 2-h level to 7.8 mmol/ (140 mg/dl). Glucose-tolerant women below this relatively low reference range have an increased rate of large-for-gestational-age infants and may benefit from treatment. 相似文献
995.
N Kimura T Ishikawa Y Sasaki N Sasano K Onodera Y Shimizu I Kimura DF Steiner H Nagura 《Canadian Metallurgical Quarterly》1996,81(1):390-395
An autopsy case of ACTH-producing thymic carcinoid with Cushing's syndrome is reported. The patient was a 63-yr-old man with multiple bone metastases from an undetermined primary site. Hyperpigmentation was observed at the terminal stage. The plasma levels of ACTH, cortisol, chromogranin A, and urinary 17-hydroxy-corticosteroids were extremely high, and ectopic ACTH-producing neuroendocrine tumor was diagnosed. In addition, plasma CRH was high. Autopsy revealed that the patient had primary thymic carcinoid with extensive metastases. Remarkable hyperplasia of the adrenal cortexes and Crooke's hyaline degeneration of the pituitary gland were consistent with Cushing's syndrome by ectopic ACTH production. There were multiple CRH-producing cells without degenerative changes in the hypothalamus. The tumor cells were immunoreactive to ACTH, CRH, and the cleavage enzyme PC2. POMC messenger ribonucleic acid and PC2 messenger ribonucleic acid were detected in the tumor cells by an in situ hybridization method. Expression of PC2 was considered to induce hyperpigmentation by producing alpha MSH. Despite hypercortisolism and ectopic production of CRH by the tumor cells, hypothalamic CRH cells were not atrophic. This case is a good example to demonstrate the correlation between CRH and the hypothalamo-pituitary-adrenal axis as well as hyperpigmentation in Cushing's syndrome. 相似文献
996.
By means of an allometric relation between the oxygen consumption rate and the body mass of an animal a metabolic coefficient is derived that can be used as a measure of standard metabolism in different animal species. This coefficient increased in the course of evolution corresponding to the time of appearance of each class of animal. It reached its highest values in Primates and passerine birds. A further increase across an energetic threshold was only possible with human civilization. A similar approach to evolution is performed through an encephalization coefficient showing that in all phases of evolution, species existed with a much larger relative brain volume than the other members of their class. These species might have established a non-human civilization on Earth if evolution would have taken another path. Finally, social activities of insects and the use of external energy sources by animals are discussed to show further implications of this bioenergetic approach to evolution. 相似文献
997.
Water proton longitudinal relaxation has been measured in agar and cross-linked bovine serum albumin (BSA) using modified selective excitation (Goldman-Shen and Edzes-Samulski) pulse sequences. The resulting recovery curves are fit to biexponentials. The fast recovery rate gives magnetization transfer (MT) information, which is complementary to that given by steady-state saturation methods. This rate provides an estimate of the strength of the coupling of the immobile proton pool to the mobile proton pool. Near their optimal pulse power values, the Goldman-Shen and Edzes-Samulski sequences give fast recovery rates that agree with each other. However, these measured fast recovery rates are dependent on the pulse power, an effect not predicted by the coupled two-pool model. For 8% agar and 17% BSA, both methods (at optimal pulse powers) give rates in the neighborhoods of 210 and 64 Hz, respectively. The Goldman-Shen and Edzes-Samulski pulse sequences have several advantages over those techniques based on steady state saturation: no long saturating pulses, shorter measurement time, and reduced necessity for making lineshape or fitting technique assumptions. The principle disadvantages are smaller effects on the NMR signal, less complete characterization of the MT system, and, in the case of the Goldman-Shen sequence, greater pulse power. 相似文献
998.
DF Hanley 《Canadian Metallurgical Quarterly》1980,67(4):420-422
999.
The mechanism of spontaneous cell-mediated cytotoxicity (SCMC) of cultured cell lines has been investigated and compared with antibody-dependent cell-mediated cytotoxicity (ADCMC) by detailed kinetic analysis. The mechanism of SCMC resembles that of an enzyme, as does ADCMC where effector cells are analogous to an enzyme and the 51Cr-labeled target cells are analogous to the substrate. Temporal kinetic studies revealed an induction period of about 1 hr before significant 51Cr release for SCMC, but not for ADCMC. This induction period is not due to differences in effector-target affinity between SCMC and ADCMC. On the basis of kinetic analysis it was shown that SCMC approaches simple Michaelis-Menten enzyme kinetics, allowing determination of a Michaelis constant, Km, and maximal velocity, Vmax, for the interaction between a given effector and target cell. The Km values thus determined were found to be identical for the lysis of several target cell lines of varying SCMC susceptibility to effector cells from a given donor, whereas Vmax values for lysis of different target cells varied considerably. However, effector cells isolated from the peripheral blood of different donors exhibited different Km values for the target cells tested. Moreover, the Km value obtained for ADCMC effected by a given donor's lymphocytes was found equal to the Km value obtained for SCMC by that donor. 相似文献
1000.
A technic for total mastectomy with complete axillary dissection has been described. The procedure utilizes division of the pectoralis major muscle between its clavicular and sternal portions, perservation of its innervation, and reconstruction after completion of the dissection. The pectoralis minor muscle is resected. This modification facilitates a thorough axillary dissection, particularly at the apex, while preserving the cosmetic and functional benefits of the Patey operation. 相似文献