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1.
Multiple aspartate-specific cysteine proteases have been identified and specific members of this family have been implicated in the apoptotic death of many mammalian cell types. Caspase-3-like proteases seem to play a pivotal role in neuronal apoptosis since mice with germline inactivation of the caspase-3 gene manifest profound alterations in neurogenesis. Moreover, inhibitors of caspase-3-related proteases have been shown to inhibit neuronal apoptosis. Here we extend recent work from our laboratory on the mechanisms mediating the neurotoxic actions of 1-methyl-4-phenylpyridinium using ventral mesencephalon cultures containing dopamine neurons. We demonstrate that low concentrations of 1-methyl-4-phenylpyridinium induce apoptosis in dopamine neurons by morphological and biochemical criteria. Moreover, pretreatment of ventral mesencephalon cultures with the tetrapeptide inhibitors of the caspase-3-like proteases zVAD-FMK or Ac-DEVD-CHO specifically inhibit death of dopamine neurons induced by low concentrations of 1-methyl-4-phenylpyridinium, whereas the caspase-1-like inhibitor Ac-YVAD-CHO was without effect. Our data indicate that exposure of cultured ventral mesencephalon dopamine neurons to low concentrations of 1-methyl-4-phenylpyridinium results in apoptotic death and that caspase-3-like proteases may mediate the neurotoxic apoptotic actions of 1-methyl-4-phenylpyridinium.  相似文献   

2.
Approximately 480 deaf students (age 10 to 19 years) and 60 hearing students (age eight to 10 years) were asked to judge the grammaticality of sentences containing auxiliary verbs, of sentences where the verb had been deleted, and of sentences in which the verb tense was not marked. The results indicated that deaf students have considerable difficulty with the verb system of English. This difficulty was most pronounced in the formation of tense and voice and in agreement in number and tense. A possible ordering for the acquisition of tense did emerge; from earliest to latest it is: simple past, future, present progressive, perfective, and passive. Improvement in grammaticality judgments appeared to come from an increase in recognition that incorrect sentences were ungrammatical.  相似文献   

3.
A series of studies showed that the tendency to assign greater causal weight to one interactant than to the other in sentence-events such as A doted on B or A detested B is related to the attributive reference of the adjective derived from the sentence verb. Thus, the pattern of causal weights for doted on (which has the derived form doting to describe A but none to describe B) favors A more so than does the pattern for detested (which has the form detestable to describe B but none to describe A). The effect was shown to be completely general across the verb types studied and was also obtained in an experiment using nonsense verbs and adjectives. The findings are discussed as they bear on the Whorfian hypothesis of linguistic determinism and are interpreted as showing that the way in which people think about interpersonal causality is related to, and perhaps affected by, the content of the interpersonal lexicon. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

4.
The problem of selecting words without first ascertaining their appropriateness for representing given values, and the need for the elucidation of the psychological distinctions between value as "interest" and value as "preference" are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

5.
Over a 15-year period, thirteen thymolipomas are histologically demonstrated in a total of 182 myasthenia gravis patients undergoing thymectomy. The incidence of this rare histological diagnosis in the aforementioned group appears to be considerably higher than the one so far reported in the pertinent literature. In the series reviewed men in advanced age prevail which is by no means typical of myasthenia patients. The postoperative results are very good, with not a single fatal outcome being recorded. There are basically three types of histological findings in thymolipomas--fat tissue alone, fat tissue with thymic tissue in involution, and fat tissue with thymic tissue.  相似文献   

6.
7.
Patients with stage I or II breast cancer are candidates for either modified radical mastectomy or breast preservation therapy involving limited resection of the primary tumor, axillary dissection, and breast irradiation. The overall survival rates of both these approaches are comparable according to retrospective reviews and ongoing clinical trials, and long-term follow-up confirms the earlier findings. Thus, patients should be given the choice between these two options by surgeons, radiation therapists, and other physicians involved in their care. However, not all breast cancer patients will choose breast preservation surgery, and because of tumor-related and other factors not all patients are candidates. The patient selection criteria are discussed herein and the optimal surgical techniques are reviewed.  相似文献   

8.
Considers issues raised by H. H. Strupp and A. E. Bergin in their review of individual treatment. It is argued that the task of determining whether therapy has been successful is conceptually more complicated for hospital programs. Individual therapy is presented as a 2-party contract between the patient and therapist while hospital programs are seen as a 6-party contract including the patient, state, local community, family, hospital staff, and therapist. The goals of each of the 6 parties are presented and some incompatabilities noted. Given the multiplicity of incompatible goals, it is suggested that various treatment programs may be designed for optimal success on the terms set by 1 of the 6 parties and evaluation of outcome may involve selecting whose outcome to assess. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

9.
As an internship applicant, do you know what internship agencies look for to select or exclude you from further consideration? In a survey, the authors examined exclusion and inclusion criteria used at 402 internship sites accredited by the American Psychological Association (APA). The 249 respondents (62%) rated fit between applicant goals and site opportunities as the most important inclusion criteria. Four exclusion criteria (lack of completion of orals, lack of APA status of doctoral program, poor fit between applicant goals and site opportunities, and incomplete doctoral course work) were most commonly used to eliminate applicants from consideration. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

10.
Cochlear implants have proven to be effective and reliable in postlingually deaf adults. This is also true for congenitally deaf and perilingually deaf children up to the age of six years. Due to the increasing experience, the improvement of implant technology and the proven reliability the selection criteria are broadened with shifting borders. The main extensions are related to age, additional handicaps, residual hearing and special etiologies of deafness. Increasing evidence shows that very early implantation results in better performance and better hearing and speech development. Near-normal language acquisition can be achieved in children implanted under the age of four. Additional handicaps do not automatically exclude a candidate from cochlear implantation. A case-to-case decision has to be made based on additional diagnostics and the experience of the implant centre. A list of suitable handicaps is provided. Severely hearing impaired patients may also be considered for cochlear implantation if their residual hearing provides no benefit for speech discrimination. The same holds true for children. Cochlear implantation in obliterated cochleae and inner ear malformation requires a special surgical technique and special electrode arrays. In this way even difficult cases can be managed with remarkable outcome. Over all, the selection criteria have been broadened with increasing experience and technological improvement. This development may continue and the borderline between hearing aids and cochlear implants will shift further towards severe hearing loss. However, the basis for success still remains good rehabilitation, a team approach and the willingness of the patient to undergo the whole process of cochlear implantation.  相似文献   

11.
Observers respond faster when the task-relevant perceptual dimension (e.g., color) repeats across consecutive trials relative to when it changes. Such dimension repetition benefits (DRBs) occur in different tasks, from singleton feature search to feature discrimination of a stimulus presented on its own. Here, we argue that the DRBs observed in different tasks originate from distinct mechanisms: preselective weighting of dimension-specific feature contrast signals and, respectively, postselective stimulus processing. The multiple-weighting-systems hypothesis predicts significant DRBs across trials of different tasks that share the same weighting mechanism, but not across tasks involving different mechanisms. Experiments 1, 2, and 3 examined DRBs across localization and detection tasks (both involving feature contrast computations); across detection and identification tasks (which presumably involved different weighting systems); and across identification and discrimination tasks (both involving stimulus identification). As expected, significant DRBs were observed across different tasks in Experiments 1 and 3, but not in Experiment 2. These findings support the multiple-weighting-systems hypothesis. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

12.
We propose a standardized method for reporting language lateralization by intracarotid amobarbital procedure (IAP). We retrospectively reviewed 165 IAPs, and classified language lateralization as left, right, or bilateral by three different methods, all based on the duration of speech arrest following each injection: absolute duration, side-to-side difference, and a "laterality index" defined as (L-R/L+R). Cutoff values were obtained by studying a pure subgroup of left hemisphere dominant right-handed subjects. In 142 patients (86%), the classification remained unchanged among all three methods: left in 112 (79%), right in 19 (13%), and bilateral in 11 (8%). In the other 23 patients (14%), language classification varied among the three criteria used. The change of category was never between left and right, and always involved bilateral language. Thus, this index may be helpful in standardizing and comparing IAP results from different series.  相似文献   

13.
Larvae of Aedes albopictus from a plant of the Bromeliaceae family on the outskirts of S. Paulo, SP, Brazil, were collected. This occurrence sheds new light on the attempt to determine the potential of this plants as a breeding site for this mosquito in Brazil.  相似文献   

14.
PURPOSE: We report the long-term results of penile revascularization surgery for erectile failure and suggest possible selection criteria for this controversial surgical procedure. MATERIALS AND METHODS: In 7 years 62 impotent men who did not respond to pharmacotherapy underwent microsurgical penile revascularization and completed long-term followup evaluation in 41 months (range 18 to greater than 62) consisting of a detailed questionnaire, duplex sonography and optional pharmacotherapy or angiography. The Virag procedure was chosen for the first 7 patients, the original Hauri technique for the next 13 and the modified Mannheim triple anastomosis for 42. RESULTS: Of all patients 34% achieved spontaneous and another 20% pharmacologically induced erections. Success in diabetics and older patients was lower (43% for diabetics, 39% for those older than 50 years at surgery), while it was high in men with less than 2 risk factors (58%) as well as in younger patients (69% for those up to 50 years old). Shunt patency was 92%. Complications such as glans hyperemia developed in 13% of patients, shunt thrombosis in 8% and inguinal hernias in 6.5%. CONCLUSIONS: Patient selection is vital for the successful outcome of penile revascularization surgery. We adhere to strict selection criteria, such as patient age maximum of 50 years, less than 2 risk factors, no recent diabetes and termination of nicotine abuse. Penile revascularization surgery is highly indicated in this group of patients, especially since it is the only causal therapy for erectile failure.  相似文献   

15.
LW Traverso  RA Kozarek 《Canadian Metallurgical Quarterly》1997,226(4):429-35; discussion 435-8
OBJECTIVE: The authors sought to provide a framework through outcome analysis to evaluate operations directed toward the intractable abdominal pain of severe chronic pancreatitis centered in the pancreatic head. Pancreatoduodenectomy (PD) was used as an example. SUMMARY BACKGROUND DATA: Head resection for severe chronic pancreatitis is the treatment of choice for a ductal system in the head obliterated by severe disease when associated with intractable abdominal pain. To evaluate the effectiveness of promising head resection substitutes for PD, a framework is necessary to provide a reference standard (i.e., an outcome analysis) of PD. METHODS: Inclusion criteria were severe chronic pancreatitis centered in the pancreatic head, intractable abdominal pain, and a main pancreatic duct obstruction or stricture resulting in absent drainage into the duodenum from the uncinate process and adjacent pancreatic head areas or the entire gland. Since 1986, 57 consecutive cases with these criteria underwent PD (47 head only and 10 total pancreatectomy). Clinical and anatomic predictor variables were derived from the history, imaging studies, and pathologic examination. These variables then were tested for association with the following outcome events gathered during annual follow-up: pain relief, onset of diabetes, body weight maintenance, and peptic ulceration. RESULTS: Operative mortality was zero. In 57 patients with a mean follow-up of 42 months, the 5-year outcome event for survival was 93% and the onset of diabetes was 32%. All new cases of diabetes occurred more than 1 year after resection. In 43 cases > or =1 year postoperative with a mean follow-up of 55 months, all patients indicated significant pain relief and 76% were pain free. Pain relief was more common in patients with diabetes or in those patients with a pancreatic duct disruption. Death was more common in patients with diabetes. Weight maintenance was more common if preoperatively severe ductal changes were not present. Total pancreatectomy was associated with peptic ulceration. CONCLUSIONS: Using selection criteria, the outcome analysis standardized anatomic and clinical variables as to how they were associated with the outcome events (calibrated the effects of the operation with each variable). In these selected patients, PD is safe and significantly relieves pain. Sequelae are from diabetes, provided total pancreatectomy is avoided.  相似文献   

16.
Cystitis cystica, a common urothelial pathology whose aetiology, morphology and clinical significance are poorly understood, affects the human urinary bladder and trigone in both sexes. We have studied the fine structure of urothelial cysts in 11 patients diagnosed cystoscopically as suffering from cystitis cystica. Several abnormal features were observed in the adjacent urothelium, including large intracellular vacuoles (4 patients), Brunn's nest (5), lymphocyte infiltration (10) and generally disorganised urothelial architecture (10). Squamous metaplasia was observed in one case. The wall of each cyst consisted of a 2-3 layered epithelium with either tall columnar or flattened cells lining the fluid-filled lumen. Both types of lining cell possessed short microvilli, while the columnar type also contained numerous membrane-bound, electron dense secretory granules in the apical cytoplasm. Rough endoplasmic reticulum, mitochondria and Golgi membranes were plentiful in the surface cells. Junctional complexes joined adjacent lining cells. The deeper cells contained relatively fewer organelles, while a basal lamina separated the cyst wall from the underlying connective tissue.  相似文献   

17.
The assumption of strongly ignorable treatment assignment is required for eliminating selection bias in observational studies. To meet this assumption, researchers often rely on a strategy of selecting covariates that they think will control for selection bias. Theory indicates that the most important covariates are those highly correlated with both the real selection process and the potential outcomes. However, when planning a study, it is rarely possible to identify such covariates with certainty. In this article, we report on an extensive reanalysis of a within-study comparison that contrasts a randomized experiment and a quasi-experiment. Various covariate sets were used to adjust for initial group differences in the quasi-experiment that was characterized by self-selection into treatment. The adjusted effect sizes were then compared with the experimental ones to identify which individual covariates, and which conceptually grouped sets of covariates, were responsible for the high degree of bias reduction achieved in the adjusted quasi-experiment. Such results provide strong clues about preferred strategies for identifying the covariates most likely to reduce bias when planning a study and when the true selection process is not known. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
19.
The time course of lexicalization during production was explored using a production priming procedure. Participants were presented with pictures to name. Occasionally, a visual target word was presented following a picture, and participants named the word. In Experiments 1A and 1B, phonological priming was found for targets related to the dominant name of a picture, as well as for those related to a near-synonymous name. These results suggest that phonological activation occurs for multiple lexical candidates. In Experiments 2A and 2B, semantic priming was found to arise earlier than phonological priming. In Experiment 3, no priming was found for words phonologically related to category associates, suggesting that the activation of such items is weak. Overall, the results are supportive of a cascaded processing model of lexicalization in which activation spreads continuously from semantic to phonological levels of representation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

20.
Purpose: to analyze the effect of overall treatment time of radiotherapy on survival and local control in locally advanced prostatic cancer in a split-course treatment setting. Methods and Materials: 168 patients with Stage C prostatic cancer treated during 1979-1989 by the split-course method where the overall treatment time is protracted. Treatment consisted of whole pelvis irradiation of 40 Gy in 4 weeks, followed by a planned 3-week interruption and an additional 26 Gy by the reduced field technique to a total dose of 66 Gy in 9 weeks and 30-33 fractions. The overall treatment time varied from 55 to 100 days. Thirty-eight percent (63) of the patients were treated primarily with radiotherapy, while the rest (105) had received androgen ablative therapy during 2 to 4.5 years before radiotherapy. To examine the effect of treatment time on local control, the patients were divided into three groups ( < or = 63 days, 64-70 days, and > 70 days) by treatment time. Results: the 5-year actuarial survival rates, calculated from the date of diagnosis, were 91% for the hormonally manipulated patients and 69% for the patients treated with radiotherapy alone. The 5-year actuarial local control rates, counted from the start of radiotherapy, were 84% for radiotherapy and 80% for the hormonally manipulated group. Overall, no significant effect of treatment time could be seen, either for radiotherapy alone or for the hormonally manipulated group. The results were similar when the material was further divided by T category and histologic grade. Conclusions: no significant effect of overall treatment time (55 to 100 days) on survival or local control was found in either group. The survival time from diagnosis was longer in the hormonally pretreated group. Apparently, with adequate doses ( > or = 65 Gy) the overall treatment time becomes less important for local control of advanced prostatic cancer, even in a split-course treatment setting.  相似文献   

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