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排序方式: 共有468条查询结果,搜索用时 46 毫秒
1.
A spinal cord injury model is described using chymopapain as a neurotoxic agent in rats. The trauma was evaluated by neurophysiological and morphological methods. Electrically evoked compound action potentials were used to quantify the neurophysiological effects caused by the injection of chymopapain into the lumbar dural theca in rats. A branch of the sciatic nerve was stimulated with voltage impulses of constant amplitude (40 V) and duration (0.1 ms) at the right external malleolus. The responses were recorded at the dorsal root entry zone L1. We used different doses of the enzyme (1000 i.u./ml; 2500 i.u./ml; 5000 i.u./ml). A total amount of 0.1 ml was injected into the rats' lumbar spinal canal intrathecally (n = 18). The control rate (n = 8) were subjected to exactly the same stimulus and recording procedures but the test solution was a corresponding volume of isotonic saline. Two hours after injection the animals were examined clinically and then sacrificed for histology. The prolongation of the latency of the electrically evoked potentials caused by the enzyme was very clear at the doses of 2500 i.u. and 5000 i.u. being about 10-15% relative to the mean latency before administration of the drug. The histological evaluation showed hemorrhage, vascular damage and indirect signs of myelin edema of the lumbar nerve tissue. Our study indicates that chymopapain injections into the lumbar spinal canal can be used as a reproducible model for spinal cord injury research. 相似文献
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Gabriel Stefan Ana Maria Mehedinti Iuliana Andreiana Adrian Dorin Zugravu Simona Cinca Ruxandra Busuioc Ioana Miler Simona Stancu Ligia Petrescu Ioana Dimitriu Elena Moldovanu Diana Elena Crasnaru Georgeta Gugonea Valentin Georgescu Victor Dan Strambu Cristina Capusa 《Renal failure》2021,43(1):49
Background There is limited information about the clinical characteristics, treatment and outcome of maintenance hemodialysis patients with COVID-19. Moreover, regional differences are also conceivable since the extend and severity of outbreaks varied among countries.Methods In this retrospective, observational, single-center study, we analyzed the clinical course and outcomes of 37 maintenance hemodialysis patients (median age 64 years, 51% men) hospitalized with COVID-19 from 24 March to 22 May 2020 as confirmed by real-time PCR.Results The most common symptoms at admission were fatigue (51%), fever (43%), dyspnea (38%) and cough (35%). There were 59% mild/moderate patients and 41% severe/critical patients. Patients in the severe/critical group had a significantly higher atherosclerotic burden since diabetic kidney disease and vascular nephropathies were the most common primary kidney diseases and eighty percent of them had coronary heart disease. Also, Charlson comorbidity score was higher in this group. At admission chest X-ray, 46% had ground-glass abnormalities. Overall, 60% patients received hydroxychloroquine, 22% lopinavir–ritonavir, 11% tocilizumab, 24% systemic glucocorticoids, and 54% received prophylactic anticoagulation. Seven (19%) patients died during hospitalization and 30 were discharged. The main causes of death were cardiovascular (5 patients) and respiratory distress syndrome (2 patients). In Cox regression analysis, lower oxygen saturation, anemia and hypoalbuminemia at admission were associated with increased mortality.Conclusions In conclusion, we observed a high mortality rate among maintenance hemodialysis patients hospitalized for COVID-19. Anemia, lower serum albumin and lower basal oxygen saturation at admission were factors associated with poor prognosis. 相似文献
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Synoviocytes secrete factors which induce the synthesis of neutral metalloproteinases (NMP) and prostaglandin E2 (PGE2) by chondrocytes in a response called chondrocyte activation. We analyzed synovial chondrocyte activating factors (CAF) for the presence of cytokines which modulated the NMP production by articular chondrocytes. These studies suggested the presence of several other cytokines in addition to interleukin-1 (IL-1). Both resting and activated synoviocytes contained mRNA for basic fibroblast growth factor (bFGF) which is a synergist for IL-1 induced NMP production, and secreted bFGF into their culture media. They also expressed mRNA for transforming growth factor (TGF) which inhibits IL-1 induced NMP production. These cells also produce tumor necrosis factor (TNF) and trace amounts of interleukin-6 (IL-6). In addition to these there is evidence for a synovial activator of chondrocytes which is distinct from IL-1. Since a number of recombinant cytokines including TNF, IL-6 and bFGF failed to activate chondrocytes, this could be a novel cytokine. 相似文献
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The frequency of the hand trauma involving tissue losses generated the research for developing new technical solutions more simple and economic. The regional flaps, such as the distal pedicle Chinese flap, are usually surgeon's first choice whenever the local resources are over passed. Still, this type of Chinese flap would claim a major disadvantage as they involve the sacrifice of a vascular axis of the hand, sometimes even the dominant one. The operating team, would be able to avoid this inconvenience when using distal perforators based-on antibrachial radial flap; moreover, this technique would allow the covering of the substance losses, as far as the metacarpophalangeal joints. The authors report a clinical case. 相似文献
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TGF-beta-1 gene transfer in joint cartilage cells. Stimulating effect in extracellular matrix synthesis 总被引:1,自引:0,他引:1
Möller HD Fu FH Niyibizi C Studer RK Georgescu HJ Robbins PD Evans CH 《Der Orthop?de》2000,29(2):75-79
TGF beta-1 has been shown to upregulate matrix synthesis in articular chondrocytes. TGF beta-gene transfer to chondrocytes has the potential to increase the local production of this key component within regenerating cartilage after trauma and could support the repair process in articular cartilage lesions. Primary rabbit articular chondrocytes were cultured and retrovirally transfected with the experimental TGF beta-1 and the lacZ marker gene for control purposes. After radioactive labeling of new synthesized matrix proteins results were compared with normal primary chondrocytes. After TGF beta-1 gene transfer the endogenous growth factor concentration was doubled compared to normal chondrocytes and decreased in the lacZ control group. The proteoglycan synthesis in TGF beta-1 transfected chondrocytes showed a 96% increase compared to the basal production of normal chondrocytes. The LacZ transfected group revealed the opposite effect by a 44% decrease. The collagen synthesis of TGF beta-1 transfected chondrocytes was 304% compared to normal chondrocytes, predominantly type II collagen. The lacZ group collagen production was reduced by 35%. We conclude that TGF beta-1 gene transfer overcomes the decreasing effect observed by transfection with the LacZ marker gene and increases matrix synthesis in articular chondrocytes. Genetically altered chondrocytes might improve the repair of cartilage lesions by stimulating matrix synthesis and supporting the expression of the hyaline phenotype. 相似文献
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Adina Frum Carmen Maximiliana Dobrea Luca Liviu Rus Lidia-Ioana Virchea Claudiu Morgovan Adriana Aurelia Chis Anca Maria Arseniu Anca Butuca Felicia Gabriela Gligor Laura Gratiela Vicas Ovidiu Tita Cecilia Georgescu 《Nutrients》2022,14(15)
Grape pomace and berries represent natural sources of phytochemicals that can increase the quality of life of consumers by contributing to the prevention of chronic diseases; thus, the development of a dietary supplement was necessary. The raw material (r.m.) used for the development of the dietary supplement consisted of dried and powdered bilberries (Vaccinium myrtillus L.), red currants (Ribes rubrum L.), and red fermented pomaces (Vitis vinifera L.) from Feteasca Neagra and Cabernet Sauvignon cultivars. The particle size distribution, powder flow, total phenolic content (TPC), HPLC-DAD phenolic profile assessment, and radical scavenging assay (RSA) were employed for the analysis of the raw material. After encapsulation, the average mass and uniformity of mass, the disintegration, and the uniformity of content for the obtained capsules were performed to obtain a high-quality dietary supplement. All the assays performed complied to the compendial requirements and the TPC was determined at 9.07 ± 0.25 mg gallic acid equivalents/g r.m. and RSA at 48.32 ± 0.74%. The highest quantities of phenolic compounds determined were 333.7 ± 0.50 µg/g r.m. for chlorogenic acid, followed by rutin, ferulic acid, and (+)-catechin with 198.9 ± 1.60 µg/g r.m., 179.8 ± 0.90 µg/g r.m. and 118.7 ± 0.75 µg/g r.m., respectively. The results of this study can be used for the manufacturing and assessing of pilot scale-up capsule batches and thinking of quality assurance, we recommend that the industrial batch extracts should be standardized in polyphenols, and the manufacturing process should be validated. 相似文献
9.
Georgescu ES Goldberg JM du Plessis SS Agarwal A 《Obstetrical & gynecological survey》2008,63(11):725-732
As survival rates with cancer treatment are steadily increasing, many women are now facing sterility due to treatment induced ovarian failure. This review will attempt to summarize the options for trying to preserve fertility in these patients. The optimal approach depends on the type of cancer, the type of treatment (e.g., radiation and/or chemotherapy), time available till onset of treatment, patient's age, and whether the patient has a partner. Ovarian transposition remains the standard of care for women undergoing pelvic radiation, although it has been suggested that it may be combined with ovarian tissue cryopreservation. For patients about to receive chemotherapy or whole body radiation, in vitro fertilization (IVF) with embryo cryopreservation is a well established treatment with a good success rate. However, it requires delaying cancer treatment for 2 to 4 weeks and a partner or willingness to use donor sperm. When these criteria cannot be met, more experimental options include oocyte cryopreservation for later IVF and ovarian tissue cryopreservation. The tissue may be autotransplanted back to the pelvis, when the patient is in remission, to attempt spontaneous conception or subcutaneously for easy access of follicle aspiration for IVF. Alternatively, it may be xenografted to immunocompromised mice to induce follicle maturation in preparation for retrieval for IVF. Emerging treatment options for fertility preservation include medication to prevent chemotherapy-induced oocyte damage and oocyte construction from somatic cell nuclei. IVF with donor oocyte remains an established option with a very high success rate for those who fail to conceive with the above measures or who elect not to avail themselves to experimental procedures. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES: After completion of this article, the reader should be able to demonstrate knowledge about fertility preservation when counseling appropriate female cancer patients, recall current clinical strategies to assist women cancer patients to try to maintain their fertility if they wish, and appraise future strategies as they develop. 相似文献
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