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31.
Spinal orthoses produced using additive manufacturing show great potential for obtaining patient-specific solutions in clinical applications, reducing manual operations, time consumption, and material waste. This study was conducted to evaluate the production process of spinal orthoses produced by additive manufacturing, and to test the effects of 3D-printed braces on postural stability in patients with adolescent idiopathic scoliosis and osteogenesis imperfecta. Ten patients were recruited consecutively and were asked to wear a spinal orthosis produced by additive manufacturing for 2 weeks. The four phases of the production process for each brace were evaluated separately on a scale from 0 (not acceptable) to 3 (optimal). Postural stability in the unbraced and the two braced conditions (3D-printed and conventional) was assessed using validated metrics obtained from a wearable inertial sensor. The production process was evaluated as good in four cases, acceptable in five cases, and not acceptable in one case, due to problems in the printing phase. No statistically significant differences were observed in any of the postural balance metrics between the 3D-printed and conventional brace. On the other hand, postural balance metrics improved significantly with both types of braces with respect to the unbraced condition. Spinal orthoses produced with an innovative production process based on digital scans, CAD, and 3D printing are valid alternatives to conventionally produced orthoses, providing equivalent postural stability.  相似文献   
32.
Despite the rising evidence in favor of immunotherapy (IT), the treatment of oncological patients affected by so-called “cold tumors” still represents an open issue. Cold tumors are characterized by an immunosuppressive (so-called cold) tumor microenvironment (TME), which favors host immune system suppression, cancer immune-escape, and a worse response to IT. However, the TME is not a static element, but dynamically mutates and can be changed. Radiotherapy (RT) can modulate a cold microenvironment, rendering it better at tumor killing by priming the quiescent host immune system, with a consequent increase in immunotherapy response. The combination of TME radiomodulation and IT could therefore be a strategy for those patients affected by cold tumors, with limited or no response to IT. Thus, this review aims to provide an easy, rapid, and practical overview of how RT could convert the cold TME and why cold tumor radiomodulation could represent an interesting strategy in combination with IT.  相似文献   
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Plasticizers, infant nutrition and reproductive health   总被引:9,自引:0,他引:9  
Since the 1930s, plasticizers have been used to impart flexibility to an otherwise rigid polyvinylchloride (PVC). Di-(2-ethylhexyl)-phthalate (DEHP) is the most widely used plasticizer in PVC formulations. However, DEHP leaks out from PVC items with time and use and consequently it is an ubiquitous environmental contaminant. To date, very little is known about the actual extent of DEHP exposure in infants, who are believed to be the most sensitive population, as they may be exposed to several different sources (breast milk, infant formula, baby food, indoor air, and by dermal and oral exposure via indoor dust containing DEHP) since early in life and since differences in DEHP pharmacokinetics and metabolism between children and adults have been well documented. Little information exists on DEHP dietary exposure, believed to represent a major source and orally administered DEHP is converted more rapidly to MEHP than other routes of exposure. Although DEHP has been shown to induce toxicity in experimental animals, a limited but suggestive human exposure data causes a serious concern that an early in life DEHP exposure may adversely affect male reproductive tract development. Here, we report a review on dietary phthalate exposure in babies.  相似文献   
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ras and c-myc protein expression in colorectal carcinoma   总被引:6,自引:0,他引:6  
This study was performed to determine the correlation of tumor ras and c-myc oncogene expression with clinical and prognostic variables in patients prone to develop colorectal cancer. One hundred eighteen patients with colorectal cancer were studied; mean age was 40 years. Fifty-three were young patients (age 40 or less), 49 had ulcerative colitis, and 16 had multiple polyposis coli. Immunoperoxidase stains of paraffin-embedded cancer sections were performed for the c-myc and ras proteins. ras staining was found to correlate with Dukes stage and prognosis. Patients with tumors negative for ras protein stain had an actuarial five-year survival of 61 percent versus 44 percent for those tumors with a positive stain (P less than 0.05). This correlation was not seen with the c-myc stain. Positive ras oncogene stain appears to be a useful indicator of advanced stage and poor prognosis in colorectal cancer occurring in cancer-prone patients.  相似文献   
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De Felice C  Toti P  Di Maggio G  Parrini S  Bagnoli F 《Lancet》2001,357(9267):1500-1502
The diagnosis of Ehlers-Danlos syndrome is based on distinctive phenotypical characteristics such as hyperelastic skin and hypermobile joints. To date, no congenital physical markers exist for identifying patients with Ehlers-Danlos syndrome. Absence of the inferior labial (100% sensitivity; 99.4% specificity) and lingual frenulum (71.4% sensitivity; 100% specificity) was found to be associated with classical and hypermobility types of Ehlers-Danlos syndrome.  相似文献   
40.
By taking advantage of a modified osmium maceration technique, we have been able to examine by high resolution scanning electron microscopy (HRSEM) the interior of human adrenocortical mitochondria from which all soluble material has been extracted. The so-called vesicles apparent in thin sections examined by transmission electron microscopy actually are finger-like cristae as determined by HRSEM. These digitiform cristae have a segmented appearance and a bulbous tip. The segmented form of the cristae may have important metabolic implications.  相似文献   
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