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51.
Lasers in Medical Science - Physical activity raises body temperature. However, the literature does not contain studies about whether the employment of hotobiomodulation (PMB) could significantly...  相似文献   
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Hypertransaminasemia is a frequent side effect during chenodeoxycholic administration for gallstone dissolution. Evidence suggests that this effect is not mediated by lithocholic acid, the intestinal metabolite of chenodeoxycholic acid, but that toxicity is due to the chenodeoxycholic acid itself. In vitro cytotoxicity of bile salts is positively proportional to their detergent effect, which is, on the other hand, related to their hydrophobic-hydrophilic balance. We hypothesize that in vivo also liver injury can occur when the liver is perfused by an high proportion of strongly detergent bile salts. The more detergent bile salts are unconjugated or glycine conjugated, while the lesser are taurine conjugated and sulfated. Within each class the following order of decreasing detergent power can be indicated: lithocholic greater than deoxycholic greater than chenodeoxycholic greater than cholic greater than ursodeoxycholic acid. Besides chronic exogenous administration of chenodeoxycholic or deoxycholic acids, conditions in which the liver is perfused by an high mass of highly detergent bile salts are those characterized by an enhanced intestinal biodegradation of bile salts. These conditions, which are common features of some chronic inflammatory bowel diseases, are frequently associated with liver damage. On the other hand, a normally detergent bile salt pool can become hepatotoxic for liver cells which have already been injured. In this respect, as already reported for increased sulfation, the increased proportion of taurine conjugates and the reduced formation of deoxycholic acid in liver cirrhosis can be regarded as protective mechanisms. Liver toxicity induced by bile salts' detergent action can be prevented by favouring tauroconjugation or reducing the intestinal degradation of bile salts or by administering poorly detergent bile salts.  相似文献   
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The objective of this study was to further characterize the clinical and immunopathologic features of heavy chain deposition disease (HCDD), a recently described entity. Four patients were diagnosed as having HCDD on a kidney biopsy. All presented with nodular glomerulosclerosis with deposition of gamma1 heavy chains lacking CH1 epitopes, but without light chains. Two different patterns were observed in the serum. First, patients 1 and 2 had a circulating monoclonal IgGlambda containing a short gamma1 heavy chain lacking CH1 epitopes, with an apparent molecular weight of 40 kD consistent with a complete CH1 deletion. Biosynthetic experiments also showed that the deleted heavy chain was produced in excess compared with light chains, and was secreted in vitro together with half Ig molecules, although these abnormal components were not detected by Western blot analysis of whole serum. Second, patients 3 and 4 had a circulating monoclonal IgG1lambda with an apparently normal, nondeleted heavy chain subunit, but serum fractionation followed by immunoblotting revealed an isolated monoclonal gamma1 chain lacking CH1 epitopes. These data strongly suggest that renal deposition of a CH1-deleted heavy chain circulating in low amounts in the serum as a free unassembled subunit is a major feature of HCDD. The CH1 deletion is most likely responsible for the premature secretion in blood of the heavy chain by a clone of plasma cells.  相似文献   
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In Italy, where no national screening program for cervical cancer exists, organized programs have developed on a local basis. We performed the first survey of existing organized programs by mailing a standard questionnaire to a large network of possibly involved services. For the present survey, a program was defined as organized if personal invitations were sent. We identified 29 already active organized programs and 4 others in a starting phase. The target population of active programs included 2,074,820 women in the age range 25-64 years, corresponding to 13.5% of the Italian female population of the same age. The situation is rapidly evolving since many regional programs are being implemented. Most programs followed Italian and European recommendations as regards the age limits, interval between screening rounds, presence of a fail-safe system for women referred for colposcopy, presence of protocols for diagnostic workup and treatment, and presence of referral centers for such phases. However, many programs did not meet national guidelines as regards the size of laboratories interpreting smears, which were frequently small. Second-level referral centers also frequently had a very small activity. The average (weighted for size of the invited population) compliance to invitation and coverage (proportion of women with at least one test in the last 3 years) was 32.6% and 66.0%, respectively, therefore needing to be improved. Compliance to colposcopy (weighted for number of referred women) was 81.4%. We found a very high variability in the proportion of women referred for colposcopy that could only be partly explained by different referral protocols and could depend on different criteria of smear interpretation: the average (weighted for number of tested women) was 2.01%. A need for improvement in the process of evaluation and for homogenization of criteria of cytology interpretation was identified: work in this regard is on-going.  相似文献   
56.
Kindling has been suggested as a possible mechanism for cocaine-induced seizures in chronic cocaine abusers, even though no convincing examples have been reported. We report a 37-year-old woman who initially experienced generalized tonic-clonic seizures (GTC) only immediately after "crack" use. She had a normal examination, negative family or past history for seizures, and normal cranial computed tomography and EEG. After she had abused cocaine almost daily for 2 years, her EEG demonstrated bitemporal slowing with independent spikes, and seizures were no longer temporally associated with acute cocaine use. Thereafter, despite complete abstinence from cocaine and treatment with phenytoin, she continued to experience four to six GTC a month. In light of the lack of other predisposing factors for epilepsy, this case may represent an example of cocaine-induced kindling in humans.  相似文献   
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The aims of the present study were to determine the rate of misinterpretation of non‐contrast cranial CT scans by emergency specialists and trainees compared with specialist radiologists, and the proportion of misinterpretations that is consequential. A 12‐month prospective blinded cohort study was performed. One‐hundred and ninety of 1282 scans (14.8%) were misinterpreted, and 78 of these (41.1%) were of potential or actual consequence. We conclude that the performance of senior emergency department staff in non‐contrast cranial CT interpretation is no better than moderately good, and a large proportion of misinterpretations are of potential or actual clinical consequence.  相似文献   
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Angiogenesis in the bone marrow of patients with breast cancer.   总被引:3,自引:0,他引:3  
PURPOSE: Pathologic angiogenesis has been correlated with tumor growth, dissemination, metastasis, and prognosis in solid tumors including breast cancer. Angiogenesis has also been implicated in the pathophysiology of, and shown to be a therapeutic target in tumors arising in the bone marrow. The status of angiogenesis in the bone marrow of breast cancer patients is unknown. The aim of this study was to estimate the extent of bone marrow angiogenesis in this subset of patients. EXPERIMENTAL DESIGN: We studied 42 women with breast cancer in whom a bone marrow biopsy was done. Bone marrow samples were sorted according to their infiltration status by breast cancer cells. In all bone marrow sections, blood vessels were highlighted by staining endothelial cells with an antibody directed against the CD34-related antigen. A hematopathologist blind to the status of infiltration of breast cancer did the bone marrow vessel count. RESULTS: Nineteen patients (45%) had bone marrow metastasis. The bone marrow microvessel density was significantly higher in patients with bone marrow metastases compared with patients without bone marrow metastases (P < 0.0005). Median bone marrow microvessel density was 2 for the negative bone marrow group, and 15 for the positive bone marrow group. An increased microvessel density was correlated with presence of disease at last follow-up. CONCLUSIONS: This is the first study showing that bone marrow microvessel density is significantly higher in breast cancer patients with bone marrow metastases, when compared with breast cancer patients without evidence of bone marrow metastatic disease. Further research is needed to shed light into the prognostic and therapeutic relevance of this finding.  相似文献   
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