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71.
More frequent vital sign evaluation does not result in a statistically significant difference in survival or the number of transfers to the intensive care unit (for progression of disease) after adjusting for age, gender, duration of intravenous antibiotics and comorbid conditions.  相似文献   
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Summary. Several evidences suggest that cholinergic deficits may significantly contribute to dementia in Parkinson’s disease (PDD) and acetylcholinesterase inhibitors (ChEIs) have been reported to improve cognitive symptoms in PDD, without worsening parkinsonism. Nineteen PDD patients underwent brain perfusion SPECT with 99mTc-ethyl cysteinate dimer after 6 months ChEIs treatment in order to evaluate the functional correlates of clinical improvement. A clear-cut cognitive improvement was reported in PDD patients with a significant improvement of ADAS-cog total score as well as of subscores exploring executive functions (p < 0.01). MMSE total score did not significantly change after ChEIs but the subscore of attention significantly improved after therapy (p < 0.01). No difference in motor performance as evaluated by UPDRS was reported. SPM analysis showed a significant increase of perfusion (p < 0.0001) in bilateral cingulate, and frontal regions after ChEIs. Our data confirm the efficacy of ChEIs in the treatment of dementia associated with PD mainly on attention and executive functions, and the functional findings indicate that this cognitive improvement could be associated with a sort of pharmacological frontal “re-afferentation”.  相似文献   
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Mice homozygous for the recessive, cerebellar affected mutations nervous and Purkinje cell degeneration display an almost complete loss of Purkinje cells during their first two postnatal months. We have recently shown a progressive and age-related loss of Purkinje cells in mutant mice heterozygous for mutations apparently recessive, such as staggerer and reeler, and have thus chosen to investigate whether a similar Purkinje cell loss occurred with aging in +/nr and +/pcd heterozygous mice. Purkinje cells were counted on serial sections stained with thionin obtained from 17-month-old male and female heterozygous mice and their respective wild-type controls. In the case of the +/nr and wild-type mice, no difference in cell counts was observed. However, +/pcd mice had significantly fewer (-18%) Purkinje cells (143.700+/-5.400) than control wild-types (175.100+/-2.300); p<0.0001) at 17 months. These results extend our previous findings and further support the idea that apparently recessive neurological mutations may exert, at the heterozygous state, a deleterious effect upon Purkinje cells during the aging process.  相似文献   
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Senile plaques and neurofibrillary tangles (NFT) are the prominent lesions in the brain of Alzheimer's disease (AD) patients. NFT are mainly composed of an abnormally phosphorylated form of tau protein, which has lost its function to bind microtubules and promote their assembly. Tau hyperphosphorylation critically decreases tau function and precedes neurodegeneration. The majority of tau phosphorylation sites are Ser/Thr-Pro motifs, which are known to exist in two distinct cis and trans conformations. The prolyl isomerase Pin1 catalyses the conversion of those conformations. Pin1 binds to tau specifically at the Thr231-Pro site and restores tau function, either by inducing conformational changes or facilitating dephosphorylation. It has been shown that Pin1 expression levels inversely correlate with the predicted vulnerability of different brain areas to neurodegeneration and soluble Pin1 is depleted in neurons from AD brains; furthermore, Pin1 knock-out mice develop signs and symptoms of tau-related pathologies late in life. It seems that Pin1 plays an important role in maintaining tau function, thereby preserving neuronal homeostasis and preventing age-dependent neurodegeneration. DNA sequence variations in Pin1 gene may affect its expression level or function and influence the individual risk for developing AD. We screened by denaturing high performance liquid chromatography the genomic DNA of 120 AD subjects and 134 age-matched controls and we found very few and rare sequence variations in the promoter region and in exons 2 and 3. We conclude that Pin1 is a very well conserved gene, whose rare nucleotide variations have no effect on the individual genetic risk for AD.  相似文献   
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Endometrial carcinoma: paraaortic dissemination   总被引:3,自引:0,他引:3  
OBJECTIVE: The objective of our study was to identify pathologic factors predictive of tumor dissemination to paraaortic lymph nodes (LNs) in endometrial carcinoma. The identification of the risk factors may potentially facilitate selection of patients for radical surgery or radiotherapy directed to the paraaortic area (PAA). METHODS: The study population was a cohort from 612 consecutive patients with endometrial cancer surgically managed at our institution over a 10-year period. Tumor dissemination to the PAA was identified by selecting those patients who had either paraaortic LNs positive for disease at the time of primary surgery or those who subsequently experienced paraaortic failure or both (n=41; the "PA mets" subgroup). Therefore, patients for whom no information was available about the status of paraaortic LNs but who had received adjuvant irradiation to the PAA and those for whom information was not available about sites of recurrent disease were excluded from the analysis, leaving 566 patients to compose the study population. RESULTS: On the basis of univariate analysis, numerous pathologic variables were significantly (P< or =0.01) associated with PA mets. However, logistic regression analysis identified only two independent factors predictive of PA mets: positive pelvic LNs (P<0.001, OR=5.00) and lymphovascular invasion (LVI) (P=0.01, OR=1.99). Notably, only 2% of patients with negative pelvic LNs had PA mets compared with 47% of those with positive pelvic LNs (P<0.001). When both pelvic LNs and LVI were negative, only 0.8% of the patients had PA mets compared with 31% of patients for whom at least one of the two variables was positive (P<0.001). CONCLUSION: Positive pelvic LNs and LVI identify a subgroup of high-risk patients (approximately one sixth of the overall population) who potentially may benefit from formal lymphadenectomy or adjuvant therapy or both directed to the PAA. Furthermore, with 47% of patients with positive pelvic LNs having PA mets, unstaged patients at risk for pelvic LN involvement should be considered candidates for both pelvic and paraaortic external beam radiotherapy or surgical restaging.  相似文献   
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OBJECTIVES: In women with HIV-associated immunosuppression, HPV infections have an increased risk of progression to high-grade cervical intraepithelial neoplasia (CIN). With the HAART-induced prolonged survival and more protracted clinical course of AIDS, progression of CIN to cervical cancer (CC) has become a clinically relevant issue, and the mechanisms responsible for HIV-HPV interactions need further elucidation. The study design and analysis of the baseline data of our new project are presented. MATERIAL AND METHODS: This project is a combination of a prospective cohort study of HIV- and HIV+ women, and a retrospective analysis of CIN lesions and cervical cancer. Up to the present, 244 women have been enrolled (17 HIV+) and subjected to epidemiological interview, colposcopic examination, sampling for HPV testing and typing (PCR, InnoLiPA), and HPV serology. The retrospective series of biopsies were analysed for 13 biomarkers (monitoring key molecular events) using immunohistochemistry and tested for HPV by PCR and TaqMan. RESULTS: HIV- and HIV+ women differ in their exposure status to many of the key epidemiological risk factors of cervical cancer, the most significant ones being number of sexual partners (p = 0.0001), age at onset of sexual activity (p = 0.002), and contraception (yes-no) (p = 0.009). The differences in the baseline clinical observations are less dramatic; HIV-positive women had more frequent HSIL PAP tests (p = 0.040), CIN2 or higher in cervical biopsy (p = 0.049), and external genital warts (p = 0.019). The factors predicting intermediate endpoint markers of cervical cancer, i.e., HSIL PAP smear, ATZ2 in colposcopy, and high-grade CIN in biopsy were analysed in univariate and multivariate regression models. All factors significant in univariate analysis were entered in the multivariate model; HIV-status and Pap smear history maintained their independent predictive power of the HSIL Pap test. The most powerful predictor of ATZ2 colposcopy was HSIL in Pap test. Only the HSIL Pap test and ATZ2 colposcopy remained significant independent predictors of high-grade CIN (p = 0.0001 and p = 0.008, respectively) in the multivariate model. CONCLUSIONS: The three intermediate endpoint markers are closely interrelated, but predicted in part by different covariantes in the causal pathway to cervical cancer. To elucidate whether the increased risk of HIV-positive women to high-grade CIN is due a) to their different exposure status to the risk factors, b) to the direct effects of HIV, or c) to molecular interactions between HIV and HPV, we need to complete these analyses separately in HIV+ and HIV- women.  相似文献   
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