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A 12-year-old girl is described who developed rectal bleeding 5 months after being diagnosed as having a Coombs-positive hemolytic anemia. Colonoscopy showed that the rectal bleeding was due to ulcerative proctitis. This is the first case report of Coombs-positive hemolytic anemia preceding the onset of ulcerative proctitis in a child.  相似文献   
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A modern malaise   总被引:1,自引:0,他引:1  
JS Robertson Dr   《Public health》1999,113(4):155-156
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BACKGROUND: One hypothesis to explain selective serotonin reuptake inhibitor (SSRI)-induced bruxism states that SSRIs increase extrapyramidal serotonin levels, thereby inhibiting dopaminergic pathways controlling movement. Previous reports have emphasized buspirone's postsynaptic dopaminergic effect as a partial antidote to the suppressed dopamine levels. CASE REPORTS: Four patients, recently started on treatment with the SSRI sertraline, presented with new-onset complaints attributable to SSRI-induced bruxism. All 4 responded to adjunctive buspirone, a serotonin-1A (5-HT1A) receptor agonist, with relief of bruxism and associated symptoms. DISCUSSION: We expand the hypothesis put forth in previous reports by proposing that buspirone is not only acting postsynaptically in the extrapyramidal system, but also presynaptically on serotonergic neurons that influence masticatory modulation in the mesocortical tract. Our 4 cases support the concept of buspirone acting as a full agonist at the presynaptic 5-HT1A somatodendritic receptors located on the cell bodies of raphe serotonergic neurons that project to the ventral tegmental area (VTA) of the midbrain. These serotonergic neurons modulate the firing of the mesocortical tract, which itself projects from the VTA to the prefrontal cortex and acts on masticatory muscle activity through inhibiting spontaneous movements such as bruxism. While the literature is confusing and contradictory on definitions of bruxism and etiologies of incompletely understood movement disorders, we believe SSRI-induced bruxism is best conceptualized as a form of akathisia.  相似文献   
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PURPOSE: Previous studies have suggested that central zone prostatic volume may be more strongly correlated with lower urinary tract symptom severity and peak urinary flow rates than total prostatic volume. We determine whether prostatic central zone volume and central zone index volume correlate better with these measures than total prostate volume in an age stratified, community based random sample of healthy white men. MATERIALS AND METHODS: A cohort of 474 men were randomly selected from the 2,115 community dwelling men, 40 to 79 years old, who participated in the Olmsted County study of urinary symptoms and health status among men. All men had undergone transrectal ultrasound of the prostate. The total prostate and hypoechoic central zone volumes were caliper measured by 1 operator on static ultrasounds from baseline. Volumes were calculated with the prolate ellipsoid formula. The operator was blinded to clinical information and outcome. The associations between total prostate volume and central zone index (central zone volume/total volume), and American Urological Association (AUA) symptom index and peak urinary flow rates, respectively, were quantified with the Spearman rank correlation coefficient and least squares regression models. RESULTS: There was a moderately strong correlation between patient age and central zone volume (rs 0.54, p <0.001), total prostate volume (rs 0.45, p <0.001) and central zone index (rs 0.38, p <0.001). The AUA symptom index and peak flow rates correlated less strongly with central zone volume (rs 0.17, p = 0.001 and rs -0.20, p <0.001, respectively) and total volume (rs 0.16, p <0.001 and rs -0.16, p <0.001, respectively). Central zone index weakly correlated with AUA symptom index (rs 0.08, p = 0.103) and peak urinary flow rate (rs -0.08, p = 0.0823). In regression models predicting AUA symptom index and peak flow rates central zone volume added little information after accounting for age and total prostatic volume in predicting AUA symptom index (p = 0.55) and peak flow rate (p = 0.84). CONCLUSIONS: Central zone volume measured from static images optimized for total prostate volume no more closely correlated with lower urinary tract symptom severity or peak urinary flow rates than total prostate volume. Thus, the potentially greater imprecision in measuring central zone volume may not be offset by gains in strength of association with lower urinary tract symptom severity or peak urinary flow rates.  相似文献   
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PURPOSE: The purpose of this study was to identify pretherapy factors associated with pelvic lymph node involvement (LNI) in patients with localized prostatic carcinoma (CaP), and to develop a model that would allow for estimation of this risk at the time of initial diagnosis. METHODS AND MATERIALS: Between January 1988 and December 1992, 2439 patients with clinical Stage T1a-3cN0-XM0 CaP underwent radical retropubic prostatectomy and bilateral pelvic lymph node dissection as sole initial therapy at a single medical institution. Preoperative factors were evaluated for their association with pelvic LNI in univariate and multivariate logistic regression analysis. A model was developed that incorporated independent predictive variables, and probability plots were generated to estimate the likelihood of pelvic LNI in the patient with a new diagnosis of localized CaP. RESULTS: Within clinical tumor stage, three groups (Tla-2a, T2b-c, and T3) were identified in which the observed rate of pelvic LNI was distinctly different. Gleason primary grades were also combined (1-2, 3, and 4-5) because of a similar observation. Univariate analysis identified clinical tumor stage (p < 0.0001), Gleason primary grade (p < 0.0001), and serum prostate-specific antigen (p < 0.0001) as factors associated with pelvic LNI. Each of these variables retained independent significance (p < or = 0.0002) in the multivariate model. Patient age (p = 0.12) and history of prior transurethral resection of the prostate (p = 0.36) were not found to correlate with this endpoint. Probability plots provided an estimate of the likelihood for pelvic LNI according to the combination of pretherapy clinical tumor stage, Gleason primary grade, and serum prostate-specific antigen level. CONCLUSION: Clinical tumor stage as determined by digital rectal examination, Gleason primary grade of the diagnostic biopsy specimen, and pretherapy serum prostate-specific antigen value can be combined to estimate the probability of pelvic LNI for the patient with a new diagnosis of localized CaP. This information may be of value in directing the pretherapy diagnostic evaluation, as an aid in radiation therapy treatment planning, and in the conduct of clinical research efforts.  相似文献   
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A nationwide study of intracellular drug metabolite concentrations in children prescribed 6-mercaptopurine for the treatment of lymphoblastic leukaemia was carried out to assess interpatient variability at a standardised dose. Nine children (2% of the total) had completely undetectable metabolites, indicative of non-compliance. Five were adolescents, but otherwise they had no obvious distinguishing characteristics. Not taking any 6-mercaptopurine at all is uncommon, but the problem cannot be predicted. The total number of children who do not comply cannot be determined from this study, but the nine children described represent only a fraction of these.  相似文献   
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The nucleocapsid (N) protein of SARS-coronavirus (SARS-CoV) is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DHSalpha and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobutins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity (DTH) and CD^8+ CTL responses to N protein.  相似文献   
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