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91.
Previous research has shown that word-to-picture matching for targets that cannot be named at pre-test results in improved naming relative to untreated control items for people with aphasia. This paper replicates and extends this finding and investigates its source. Is the effect a result of priming of semantic representations, or of post-semantic mechanisms in word retrieval? The first experiment shows that word-to-picture matching with unrelated distractors improves naming at short (2-3 minutes) and long (up to 25 minute) lags. There was no effect of being made aware of the relationship between word-to-picture matching and picture naming. People who have a semantic impairment improve only with a short lag between word-to-picture matching and naming. Participants with less semantic impairment show larger priming effects that are equal at short and long lags between word-to-picture matching and naming. The second experiment shows that the facilitation effect is just as large for word-to-picture matching with unrelated distractors as with semantically-related distractors. Furthermore, overall there was no difference between matching with coordinate items and with associated items. The results of these experiments show that facilitation of naming by word-to-picture matching in people with aphasia cannot be a result of the priming of semantic representations. Instead they are consistent with two effects: word-to-picture matching results in priming at a lemma level for aphasic people with a semantic impairment that is only found with a short lag between word-to-picture matching and naming. Word-to-picture matching causes priming of the lemma to output lexicon entry mapping that benefits participants with less semantic impairment that is evident at both a short and long lag between word-to-picture matching and naming. These findings fit well with previous research on repetition priming of naming with normal subjects.  相似文献   
92.
Neurodegenerative diseases are often classified based on the abnormal accumulation of synuclein or tau. Traditionally, these disorders have been viewed as distinct clinical and pathological entities. However, advances in molecular genetics and protein biochemistry have shown intriguing overlaps. The most common synucleinopathy, Parkinson's disease, is characterized by extrapyramidal motor dysfunction, whereas the most common tauopathy, Alzheimer's disease, is defined by dementia. Yet there is overlap of clinical features; Parkinson's disease patients frequently have dementia, and Alzheimer's disease patients often manifest parkinsonism. Dementia with Lewy bodies exemplifies the existence of a continuum among these diseases. This overlap extends to the neuropathological findings; the pathognomonic hallmark for one set of disorders, Lewy bodies or neurofibrillary tangles, is present more often than expected in the other set. Moreover, mutations in LRRK2 known to cause parkinsonism are associated not only with dopaminergic neuronal degeneration, but also with the accumulation of synuclein, tau, neither, or both proteins. Other shared genetic features between tauopathies and synucleinopathies also exist. Finally, the known protein interactions between tau and synuclein further highlight the interface. Evidence for the intersection of tauopathies and synucleinopathies indicates the need for an updated disease classification scheme and may have important implications for therapeutic development.  相似文献   
93.
OBJECTIVE: This paper, composed by an interest group of clinicians and researchers based in Melbourne, presents some background to the practice of mindfulness-based therapies as relevant to the general professional reader. We address the empirical evidence for these therapies, the principles through which they might operate, some practical questions facing those wishing to commence practice in this area or to refer patients into mindfulness-based therapies, and some considerations relevant to the conduct and interpretation of research into the therapeutic application of mindfulness. METHOD: Databases (e.g. PsycINFO, MEDLINE) were searched for literature on the impact of mindfulness interventions, and the psychological and biological mechanisms that underpin the effects of mindfulness practice. This paper also draws upon the clinical experience of the author group. RESULTS: Mindfulness practice and principles have their origins in many contemplative and philosophical traditions but individuals can effectively adopt the training and practice of mindfulness in the absence of such traditions or vocabulary. A recent surge of interest regarding mindfulness in therapeutic techniques can be attributed to the publication of some well-designed empirical evaluations of mindfulness-based cognitive therapy. Arising from this as well as a broader history of clinical integration of mindfulness and Western psychotherapies, a growing number of clinicians have interest and enthusiasm to learn the techniques of mindfulness and to integrate them into their therapeutic work. This review highlights the importance of accurate professional awareness and understanding of mindfulness and its therapeutic applications. CONCLUSIONS: The theoretical and empirical literatures on therapeutic applications of mindfulness are in states of significant growth and development. This group suggests, based on this review, that the combination of some well-developed conceptual models for the therapeutic action of mindfulness and a developing empirical base, justifies a degree of optimism that mindfulness-based approaches will become helpful strategies to offer in the care of patients with a wide range of mental and physical health problems.  相似文献   
94.
BACKGROUND: Feasibility of repeat lengthening has been demonstrated in animals, but in humans, none of the three clinical case reports have achieved enteral autonomy after secondary lengthening with serial transverse enteroplasty (STEP). PATIENTS AND METHODS: Institutional Review Board approved retrospective review of a single center series of repeat intestinal lengthening after prior Bianchi lengthening or STEP. Outcome measures examined include patient survival, weaning from parenteral nutrition, and need for intestinal transplantation. RESULTS: Repeat lengthening with STEP was performed 16 times in 14 patients including 2 adults and 7 male patients after prior Bianchi (n=7) and prior STEP (n=7). Median time after initial lengthening to reSTEP was 12 months (2 months-15 years). Median remnant bowel length before initial lengthening was 35 cm (15-110), before reSTEP was 56.5 cm (27-100) and final length after reSTEP was 90 cm (39-120). Survival is 100% with a median follow-up of 14.5 months (1-65 months). Discontinuation of parenteral nutrition (PN) after reSTEP was achieved in 6 of 14 (43%) patients at a median of 3 months (0.5-13 months) after reSTEP. Intestinal transplant salvage was performed in four patients at 7, 9, 13 months, and 4.6 years, respectively, after reSTEP. All four of those undergoing intestinal transplantation have also subsequently discontinued PN. CONCLUSIONS: Repeat lengthening is technically feasible after either of the available surgical lengthening procedures (Bianchi and STEP). In the stable patient, who is unable to wean from PN, repeat lengthening led to discontinuation of TPN in almost half of these carefully selected patients and does not preclude intestinal transplantation.  相似文献   
95.
Craniotubular hyperostosis are a group of high bone mass disorders related to mutations in the LRP5 and SOST genes, although other causative genes remain to be identified. Little is known about the bone turnover and the response to T3 or glucocorticoids in these patients. We describe a patient with craniotubular hyperostosis, including mutation analyses of the LRP5, SOST, DKK1 and KRM1 genes. We also studied bone turnover and bone mineral density (BMD), before and after a trial with T3 (75 microg/d for 28 weeks) and T3 and prednisone (T3 100 microg/d for 2 weeks, followed by 10 weeks on prednisone 10 mg/d, and a final 2 weeks period off of medicactions, completing 3 cycles in 42 weeks. Mutation analysis of the complete coding region and flanking highly conserved sequences of SOST, evaluation of the presence of the 52-kb deletion associated with Van Buchem disease in Dutch patients and mutation analysis of exons 2-4 of LRP5, and the coding regions of DKK1 and KRM1 did not reveal any disease-causing mutations. A baseline 5 to 7 fold increase in osteocalcin and in deoxypiridinoline was detected. After 4 weeks on 75 microg/d of T3, osteocalcin decreased 36%, but at week 28, it returned to basal. Deoxypiridinoline did not change. After the first cycle on T3 and prednisone, osteocalcin decreased 72%, and at the end of the third cycle it remained 44% below basal value. Deoxypiridinoline was stable and high during the three cycles; no changes in BMD were observed. As we failed to identify any disease-causing mutations in our patient with craniotubular hyperostosis, we suggest that another gene must be involved in the pathogenesis of his condition. This study provides additional data about the high bone turnover described in craniotubular hyperostosis, and also suggests an abnormal response to T3 excess in this condition.  相似文献   
96.
Background Laparoscopic adrenalectomy (LA) is the preferred surgical approach for pheochromocytomas. We have investigated the changes in diagnosis, management and outcome of pheochromocytomas treated since the widespread advent of LA. Methods Data were collected retrospectively from 96 patients with pheochromocytomas that had been surgically treated at three tertiary referral centers. Results There were 53 females. Mean age was 47 years (10–81). Tumors were found incidentally in 40% of patients. Of the 96 patients, 12 (13%) had familial syndromes. CT or MRI localized the adrenal lesion in all patients. MIBG scans obtained from 32 patients were concordant with the CT/MRI in 19, were false negative in 9 and misleading in 1, and altered management in only 3 patients. Mean tumor size was 5.6 cm (1.8–17). There were 92 adrenal pheochromocytomas and 9 paragangliomas. Laparoscopy was successful in 67 of 74 (91%) patients, with 20 of 67 (30%) having tumors of 6 cm or greater in size. Conversions to open procedures were performed in patients with 4 left, 2 right pheochromocytomas and 1 paraganglioma. Of the patients, 22 had an open procedure due to suspicion of malignancy or large tumors. Malignancy was observed in 4 of 92 (4.3%) pheochromocytomas and 4 of 9 (44%) paragangliomas. Average follow-up was 22 months (1–122). There were seven recurrences. Postoperative biochemical tests available in 64 patients were normal in 90%. Conclusions The diagnosis of pheochromocytoma was made incidentally in 40% of patients. MIBG is not necessary for unilateral non-hereditary pheochromocytomas localized by CT/MRI. LA is possible with excellent results in most patients, including for treatment of lesions 6 cm or greater in size with no signs of invasion. Laparoscopy should be used cautiously for paragangliomas because of a high rate of malignancy.  相似文献   
97.
OBJECTIVE: This Evidence-Based Case Management article evaluates and grades the evidence for two anesthesiology-related interventions: prophylaxis after unintentional meningeal puncture and treatment of spontaneous intracranial hypotension (SIH). METHODS: A search was made of relevant English language clinical studies or reports pertinent to the topic of low-pressure headache, but excluding the treatment of meningeal puncture headache. RESULTS: Thirty-seven case reports, case series, and clinical trials were included to develop the best available evidence-based recommendations for the prophylaxis of unintentional meningeal puncture and for the treatment of SIH. CONCLUSION: The highest quality randomized controlled trials suggest that prophylactic epidural blood patch (EBP) does not reduce the incidence of headache after unintentional meningeal puncture. The weight of existing literature supports EBP as an initial treatment of SIH, although its effectiveness does not approach that seen when EBP is used to treat meningeal puncture headache.  相似文献   
98.
BACKGROUND: Evidence from animal studies indicate a crucial role for CD25(bright+) regulatory T cells in transplantation tolerance. METHODS: To assess whether peripheral CD25(bright+) T cells control immune responses in immunosuppressed kidney transplant patients, we analyzed the suppressive capacities of these cells using mixed lymphocytes reactions. RESULTS: Allogeneic stimulation of patients peripheral blood mononuclear cells was associated with IL-2 production and T-cell proliferation. Depletion of CD25(bright+) T cells resulted in a 35% (median) higher IL-2 production and a 38% higher proliferative response against third party cells, showing that functional regulatory CD25(bright+) T cells were present (p = 0.03 and 0.02 respectively). In eight out of 11 patients, we also demonstrated regulation activity against donor-activated T cells (p = 0.03). These data were confirmed in coculture experiments with isolated CD25(-/dim) T cells plus CD25(bright+) T cells. At a 1:2 ratio, the CD25(bright+) T cells suppressed the proliferation of CD25(-/dim) donor- and third party-stimulated responder T cells. CONCLUSIONS: CD25(bright+) T cells with immune regulatory activities against anti-donor-responsive T cells are readily detectable in renal allograft recipients during treatment with full dosage immunosuppression. Whether CD25(bright+) T cells indeed play a role in graft acceptance after organ transplantation in patients remains to be elucidated.  相似文献   
99.
Silicone gel implants in breast augmentation and reconstruction   总被引:3,自引:0,他引:3  
Silicone gel implants have been widely used for breast augmentation and reconstruction since the 1960s. Several alterations to both elastomer shell and filler gel have been made over the years to improve their ability to replicate the natural breast and to decrease the incidence of capsular contracture. The latter is a pathologic process involving the periprosthetic tissues formed in response to the presence of the implant. When severe, capsular contracture may cause firmness, distortion, and pain. In response to many claims of implant-related connective tissue disease, the US Food and Drug Administration placed a moratorium in 1992 on silicone gel breast implants for cosmetic purposes. Despite a preponderance of scientific data to their safety, silicone gel implants are presently available in the United States only as part of limited clinical trials. They continue to be used in Europe and other parts of the world.  相似文献   
100.

Background

A history of childhood maltreatment and psychopathology are common in adults with obesity.

Objectives

To report childhood maltreatment and to evaluate associations between severity and type of childhood maltreatment and lifetime history of psychopathology among adults with severe obesity awaiting bariatric surgery.

Setting

Four clinical centers of the Longitudinal Assessment of Bariatric Surgery Research Consortium.

Methods

The Childhood Trauma Questionnaire, which assesses presence/severity (i.e., none, mild, moderate, severe) of physical abuse, mental abuse, physical neglect, mental neglect, and sexual abuse, was completed by 302 female and 66 male bariatric surgery patients. Presurgery lifetime history of psychopathology and suicidal ideation/behavior were assessed with the Structured Clinical Interview for DSM-IV and the Suicidal Behavioral Questionnaire-Revised, respectively. Presurgery lifetime history of antidepressant use was self-reported.

Results

Two thirds (66.6%) of females and 47.0% of males reported at least 1 form of childhood trauma; 42.4% and 24.2%, respectively, at greater than or equal to moderate severity. Among women, presence/greater severity of childhood mental or physical abuse or neglect was associated with a higher risk of history of psychopathology (i.e., major depressive disorder, posttraumatic stress disorder, other anxiety disorder, alcohol use disorder, binge eating disorder), suicidal ideation/behavior and antidepressant use (P for all ≤ .02). These associations were independent of age, race, education, body mass index, and childhood sexual abuse. Childhood sexual abuse was independently associated with a history of suicidal ideation/behavior and antidepressant use only (P for both ≤ .05). Statistical power was limited to evaluate these associations among men.

Conclusion

Among women with obesity, presence/severity of childhood trauma was positively associated with relatively common psychiatric disorders.  相似文献   
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