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951.
To explore the factors of effect on social disability of schizophrenics and nursing to the schizophrenics, 100 discharged schizophrenics were investigated and studied, with Social Disability Screening Schedule (SDSS) and questionnaire of factors of effect on social disability. The result showed SDSS scores of 53% schizophrenics were over or equal 2, and the social disability were significant positive correlated with patient's age, treatment effect, education, psychosocial factors, compliance, recovery confidence, working chance, and family monthly average income. The result suggested that nursing of three aspect, including mental care, family education, and social support, was benefit for reducing the social disability of schizophrenics.  相似文献   
952.
The birthrate has decreased for all age groups except for adolescents. 4.51% of all pregnancies in Spain fall within the 15-19 year old age group. The prevention of adolescent pregnancy indicates the need for making family planning services more accessible to young people. The object of this study was a review of medical consultations performed in 1993 with adolescents at a family planning service. Among the most significant results are the following: the average age of menarche and coitus primaris was 11.8 years (+ or -2.2 years) and 16 years (+ or -1.7) respectively. The period between coitus primaris and the act of going to a family planning center was 9.1 months (+ or -2.3). 81.7% of those adolescents were advised to take oral contraceptives, 12.4% condoms, 1.96% the I.U.D. and 3.9% none. Among the most common side effects noted after taking oral contraceptives for 6 to 12 months were: psychic alterations (changes of mood, etc.), spotting, digestive upset, migraines and weight increase. The number of sexual partners before and after contraceptive use did not change significantly.  相似文献   
953.
The influence of stereoscopic vision on the perception of optic flow fields was investigated in experiments based on a recently described illusion. In this illusion, subjects perceive a shift of the center of an expanding optic flow field when it is transparently superimposed by a unidirectional motion pattern. This illusory shift can be explained by the visual system taking the presented flow pattern as a certain self-motion flow field. Here we examined the dependence of the illusory transformation on differences in depth between the two superimposed motion patterns. Presenting them with different relative binocular disparities, we found a strong variation in the magnitude of the illusory shift. Especially when translation was in front of expansion, a highly significant decrease of the illusory shift occurred, down to 25% of its magnitude at zero disparity. These findings confirm the assumption that the motion pattern is interpreted as a self-motion flow field. In a further experiment we presented monocular depth cues by changing dot size and dot density. This caused a reduction of the illusory shift which is distinctly smaller than under stereoscopic presentation. We conclude that the illusory optic flow transformation is modified by depth information, especially by binocular disparity. The findings are linked to the phenomenon of induced motion and are related to neurophysiology.  相似文献   
954.
LG Dodd  BJ Kerns  RK Dodge  LJ Layfield 《Canadian Metallurgical Quarterly》1997,64(4):280-7; discussion 287-8
BACKGROUND AND OBJECTIVE: Intratumoral heterogeneity for prognostic factors (ploidy, proliferation, hormone receptor positivity) has been demonstrated in primary breast carcinoma by both flow cytometric and image analysis methods. Previously, heterogeneity in tumors had been demonstrated for only singular parameters. Our objective, using maps of tumors in which discrete regions can be analyzed simultaneously for DNA index (DI) and proliferative activity, was to demonstrate heterogeneity with respect to two parameters and to determine whether any interparametric relationships existed. METHODS: We analyzed 25 cases of archived, paraffin-embedded breast carcinoma (ductal) for Feulgen stain DNA analysis and MIB-1 immunohistochemistry using the CAS 200 Image Cytometer. For each tumor, four discrete regions were analyzed including tumor-host tissue interface sectors. RESULTS: Of 25 cases, 19 (76%) were homogeneously diploid or near-diploid aneuploid, and 6 (24%) were heterogeneous. Within the heterogeneous group, all cases had at least one diploid and one or more aneuploid populations from separate discrete regions. Five of six DI heterogeneous tumors displayed diploid values for the overall measurements of the respective tumors, based on analysis of 200 or more nuclei. Eight of 25 cases (32%) showed significant measurable variation for MIB-1 proliferative activity in various sectors of tumor. All the MIB-1 heterogeneous tumors, with one exception, were homogeneously diploid. CONCLUSIONS: These findings demonstrate that (1) heterogeneity is present with respect to DI and proliferative activity in breast carcinoma and is relatively common, (2) tumors homogeneous for one parameter may be heterogeneous for another, and (3) heterogeneity for proliferative activity is more common in homogeneously diploid tumors than in heterogeneous/aneuploid tumors.  相似文献   
955.
The function and nature of inhibition of neurons in the visual cortex have been the focus of both experimental and theoretical investigations. There are two ways in which inhibition can suppress synaptic excitation. In hyperpolarizing inhibition, negative and positive currents sum linearly to produce a net change in membrane potential. In contrast, shunting inhibition acts nonlinearly by causing an increase in membrane conductance; this divides the amplitude of the excitatory response. Visually evoked changes in membrane conductance have been reported to be nonsignificant or weak, supporting the hyperpolarization mode of inhibition. Here we present a new approach to studying inhibition that is based on in vivo whole-cell voltage clamping. This technique allows the continuous measurement of conductance dynamics during visual activation. We show, in neurons of cat primary visual cortex, that the response to optimally orientated flashed bars can increase the somatic input conductance to more than three times that of the resting state. The short latency of the visually evoked peak of conductance, and its apparent reversal potential suggest a dominant contribution from gamma-aminobutyric acid ((GABA)A) receptor-mediated synapses. We propose that nonlinear shunting inhibition may act during the initial stage of visual cortical processing, setting the balance between opponent 'On' and 'Off' responses in different locations of the visual receptive field.  相似文献   
956.
Electrophoretic variants of the vitamin D-binding protein (DBP) have been associated with type 2 diabetes as well as with metabolic characteristics that predispose to type 2 diabetes in several populations. The Gc gene that encodes DBP maps to chromosome 4q12, a region that has recently been found to be potentially linked to plasma glucose and insulin concentrations in Pima Indians. Therefore, the gene that encodes DBP was analyzed as a candidate gene for our linkage findings in the Pima Indians. Sequence analysis of the coding exons identified two previously described missense polymorphisms at codons 416 and 420, which are the genetic basis for the three common electrophoretic variants of DBP (Gc1f, Gc1s, and Gc2). These variants in DBP were associated with differences in oral glucose tolerance in nondiabetic Pima Indians.  相似文献   
957.
958.
959.
BACKGROUND: Image-guided percutaneous drainage has been shown to be a safe and effective alternative to surgery in the management of psoas abscess in adults and adolescents. There is little information on its use in children. OBJECTIVE: To evaluate the safety and efficacy of US-guided percutaneous needle aspiration and catheter drainage of ilio-psoas abscesses. MATERIALS AND METHODS: A retrospective review of 14 children with 16 ilio-psoas abscesses (10 pyogenic and 4 tuberculous) who were treated by US-guided percutaneous needle aspiration (n = 5) or catheter drainage (n = 9) along with appropriate antimicrobial therapy. RESULTS: Percutaneous treatment was successful in 10 of the 14 patients; all showed clinical improvement within 24-48 h of drainage and subsequent imaging demonstrated resolution of the abscess cavities. Surgery was avoided in all of these ten patients except one, who underwent open surgical drainage of ipsilateral hip joint pus. Of the other four patients, two had to undergo surgical drainage of the ilio-psoas abscesses after failure of percutaneous treatment, one improved with antibiotics after needle aspiration failed to yield any pus, and one died of continuing staphylococcal septicaemia within 24 h of the procedure. There were no procedural complications. CONCLUSIONS: Percutaneous drainage represents an effective alternative to surgical drainage as a supplement to medical therapy in the management of children with ilio-psoas abscesses.  相似文献   
960.
PURPOSE: This retrospective study was conducted to review the results of treatment and to identify prognostic factors for local and regional control in a population of 378 patients with nasopharyngeal carcinomas treated in a single institution by radiation therapy alone. METHODS AND MATERIAL: All patients were treated at The University of Texas M. D. Anderson Cancer Center between 1954 and 1992 following a consistent treatment philosophy but with evolving technique. There were 286 males and 92 females with a median age of 52 years (range: 16-86 years). The majority of the patients were Caucasian (282 patients, 75%). Thirty-two patients (8%) had one or more cranial nerve deficits. Three-fourths of the patients presented with AJCC Stage IV disease (T4, N0-3, 118 patients; T1-3, N2-3 164 patients). Histologically, 193 tumors (51%) were squamous cell carcinomas, 154 (41%) lymphoepitheliomas, and 31 (8%) unclassified carcinomas. Average total dose varied with T-stage and ranged from 60.2 to 72.0 Gy. Median follow-up time was 10 years. RESULTS: For the entire population the 5-, 10-, and 20-year actuarial survival rates were 48, 34, and 18%, respectively, with 184 patients (49%) dying of nasopharyngeal cancer. Actuarial control rates at 5, 10, and 20 years were 71, 66, and 66% for the primary site and 84, 83, and 83% for the neck. A total of 100 patients (26%) had local failures and 51 patients (13%) had regional failures with a median time to recurrence of 8.2 months and 13 months, respectively. Advanced T-stage, squamous histology, and presence of cranial nerve deficits were poor prognostic factors for local control in both univariate and multivariate analyses. N-stage and tumor histology were significant factors for neck control. Treatment year, total dose within the ranges used, and duration of treatment did not have any significant effect on local or regional control. The actuarial incidence of Grade 3-5 late complications was 16, 19, and 29% at 5, 10, and 20 years, respectively. Twelve patients (3%) died of treatment-related complications; all but one fatal complication occurred before 1971 and the other in 1976. CONCLUSIONS: This study shows very good long-term local and regional control rates for nasopharyngeal carcinomas after definitive radiotherapy and establishes a benchmark for newer treatment strategies. Improvements in treatment technique over the years have dramatically reduced the frequency of severe late complications. Patients with advanced stage tumors and differentiated squamous histology have a relatively poor prognosis when treated with conventional radiotherapy and are candidates for dose escalation or combined modality studies.  相似文献   
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