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971.
Vitamin D deficiency has been reported previously in patients with osteoarthritis undergoing total hip arthroplasty. We found a high prevalence of vitamin D deficiency in elderly patients with advanced knee osteoarthritis scheduled for total knee replacement and also a significant association with a lower preoperative functional state. A review of the literature is given on vitamin D deficiency in patients with knee osteoarthritis and the association with lower outcome scores after arthroplasty is discussed. 相似文献
972.
973.
JA Shelton JJS Brown JA Young 《Annals of the Royal College of Surgeons of England》2014,96(5):369-372
Introduction
Diagnostic laparoscopy with appendicectomy (LA) has become the accepted method of investigation and treatment of appendicitis. However, concerns remain in cases of complicated appendicitis when many advocate conversion to an open procedure (LCOA) owing to the risk of complications. The aim of this study was to look for factors that could predict complications occurring in patients undergoing appendicectomy.Methods
Data inclusive of all consecutive appendicectomies over a two-year period were retrieved from the computerised theatre database. Clinical details including admission inflammatory markers, complications, severity (final pathology) and length of stay were collected from the discharge letter. Readmissions were identified as those hospital identifiers had a second set of admission dates and/or a second discharge letter.Results
During the 2-year study period, 517 appendicectomies were performed. Of these, 429 patients (83%) had LA and the remaining 88 (17%) had LCOA. The LA group had a mean age of 28 years (range: 2–86 years) and a mean C-reactive protein (CRP) level of 71mg/l (range: 0–480mg/l) while the LCOA group had a mean age of 46 years (range: 11–92 years) and a mean CRP level of 162mg/l (range: 3–404mg/l). These differences in age and CRP were significant (p<0.001). LA patients were less likely to have complications overall (22% vs 52%, p=0.015). Complications were independently more than twice as common with established inflammation with a CRP level of >150mg/l (p<0.05).Conclusions
A high preoperative CRP level predicts an increased rate of postoperative complication due to established inflammation and/or infection. This raises the question of whether we should be offering primary open appendicectomies to patients with a CRP level of >150mg/l. 相似文献974.
975.
LJ Hale GI Welsh CM Perks JA Hurcombe S Moore I Hers MA Saleem PW Mathieson AJ Murphy M Jeansson JM Holly SN Hardouin RJ Coward 《The Journal of pathology》2013,230(1):95-106
Podocytes are crucial for preventing the passage of albumin into the urine and, when lost, are associated with the development of albuminuria, renal failure and cardiovascular disease. Podocytes have limited capacity to regenerate, therefore pro‐survival mechanisms are critically important. Insulin‐like growth factor‐II (IGF‐II) is a potent survival and growth factor; however, its major function is thought to be in prenatal development, when circulating levels are high. IGF‐II has only previously been reported to continue to be expressed in discrete regions of the brain into adulthood in rodents, with systemic levels being undetectable. Using conditionally immortalized human and ex vivo adult mouse cells of the glomerulus, we demonstrated the podocyte to be the major glomerular source and target of IGF‐II; it signals to this cell via the IGF‐I receptor via the PI3 kinase and MAPK pathways. Functionally, a reduction in IGF signalling causes podocyte cell death in vitro and glomerular disease in vivo in an aged IGF‐II transgenic mouse that produces approximately 60% of IGF‐II due to a lack of the P2 promoter of this gene. Collectively, this work reveals the fundamental importance of IGF‐II in the mature podocyte for glomerular health across mammalian species. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
976.
977.
Laparoscopic adrenalectomy for functioning and non-functioning adrenal tumors: Analysis of surgical aspects based on histological types 总被引:2,自引:0,他引:2
BACKGROUND: The aim of this study was to evaluate whether hormonal functions of the tumor influence the operative results of laparoscopic adrenalectomy, and to analyse the clinical outcomes in patients with various hormonally active adrenal tumors. METHODS: Clinical and pathological records of 68 patients were reviewed. The average age of patients was 40 years (range 20-75); 39 were women and 29 men. For the comparison, patients were divided into the non-functioning tumor group (n = 22) and the functioning tumor group (n = 46). RESULTS: All laparoscopic adrenalectomies were finished successfully, and no open surgery was necessary. The median operative time and blood loss in the two groups were similar; however, in subgroup analysis, operative time for pheochromocytoma was significantly longer than that for non-functioning tumor (P = 0.044). No difference was noted in intra- and postoperative data between the groups. Of the 22 patients with aldosteronoma, 18 (81.8%) became normotensive and no longer required postoperative blood pressure medications. Adrenalectomy led to an overall reduction in the median number of antihypertensive medications (P < 0.001). All patients with Cushing adenoma had resolution or improvement of the signs and symptoms during follow-up periods. There was no evidence of biochemical or clinical recurrence in any patient with pheochromocytoma. CONCLUSION: The results of this retrospective review document that laparoscopic adrenalectomy is a safe and effective treatment for functioning as well as non-functioning adrenal tumors, although endocrinologic features may play a significant role. 相似文献
978.
A C Collier M D Tingle J A Keelan J W Paxton M D Mitchell 《Drug metabolism and disposition》2000,28(10):1184-1186
The fluorescent compound 4-methylumbelliferone (4MU) can be used to detect uridine diphosphate glucuronosyl transferase activity by observing the fall in fluorescence as the compound is converted to 4-methylumbelliferone glucuronide. A microplate assay has been developed that has improved sensitivity and is faster and cheaper than the historical extraction method. Activity is detectable with approximately 10% of the protein required in the extraction method. Absence of extraction and cleanup procedures and the ability to observe reaction rate directly are also of great advantage to the researcher. Michaelis-Menten kinetic data from one healthy female human liver is presented. The extraction method yielded a mean V(max) of 19.9 nmol/min/mg of protein and a mean K(m) of 652.5 microM on 1 day [n = 6, coefficients of variation (CV) 15 and 24%, respectively]. For the microplate method on 1 day, the mean V(max) was 36.21 +/- 1.3 nmol/min/mg of protein (CV = 3.7%), significantly (P <.0001) higher than for the extraction method. The mean K(m), 175. 4 +/- 24.2 microM (CV = 14.5%), was significantly lower (P <.0001) than observed in the extraction method. The assay was performed in replicates of six over 6 days; average intra- and interassay coefficients of variation were 9 and 22% for V(max) and 8 and 35% for K(m), respectively, for the microplate method. The microplate method has also detected activity in the placental trophoblast-derived cell lines JEG-3, JAr, and BeWo (5.5, 4.1, and 2. 6 nmol/min/mg of protein, respectively, at 200 microM 4MU concentration), indicating that placental cells may be capable of glucuronidating 4MU. 相似文献
979.
Non-carious cervical lesions involve loss of hard tissue and, in some instances, restorative material at the cervical third of the crown and subjacent root surface, through processes unrelated to caries. These non-carious processes may include abrasion, corrosion and possibly abfraction, acting alone or in combination. Abfraction is thought to take place when excessive cyclic, non-axial tooth loading leads to cusp flexure and stress concentration in the vulnerable cervical region of teeth. Such stress is then believed to directly or indirectly contribute to the loss of cervical tooth substance. This article critically reviews the literature for and against the concept of abfraction.
Although there is theoretical evidence in support of abfraction, predominantly from finite element analysis studies, caution is advised when interpreting results of these studies because of their limitations. In fact, there is only a small amount of experimental evidence for abfraction. Clinical studies have shown associations between abfraction lesions, bruxism and occlusal factors, such as premature contacts and wear facets, but these investigations do not confirm causal relationships. Importantly, abfraction lesions have not been reported in pre-contemporary populations.
It is important that oral health professionals understand that abfraction is still a theoretical concept, as it is not backed up by appropriate clinical evidence. It is recommended that destructive, irreversible treatments aimed at treating so-called abfraction lesions, such as occlusal adjustment, be avoided. 相似文献
Although there is theoretical evidence in support of abfraction, predominantly from finite element analysis studies, caution is advised when interpreting results of these studies because of their limitations. In fact, there is only a small amount of experimental evidence for abfraction. Clinical studies have shown associations between abfraction lesions, bruxism and occlusal factors, such as premature contacts and wear facets, but these investigations do not confirm causal relationships. Importantly, abfraction lesions have not been reported in pre-contemporary populations.
It is important that oral health professionals understand that abfraction is still a theoretical concept, as it is not backed up by appropriate clinical evidence. It is recommended that destructive, irreversible treatments aimed at treating so-called abfraction lesions, such as occlusal adjustment, be avoided. 相似文献
980.
Abstract: Objectives: Local anaesthesia is increasingly used by dental hygienists. As little is known about the incidence of adverse effects during and after the administration of local anaesthetics, we evaluated side‐effects associated with local anaesthesia. Methods: A prospective observational study was conducted using standard criteria among a group of 103 patients receiving mandibular block anaesthesia. Results: Physical reactions like clenching fists (14.5%), moaning (12.6%) and turning pale (7.8%) were frequently observed. Patients (3.8%) showed a painful reaction because of needle contact with a nerve or the periosteum. Systemic complications were not observed. After the injection, 41.7% said they felt tense during the administration; 4.9% of the patients reported swallowing problems and 3.9% a tachycardia. Conclusions: These results suggest that administration of local anaesthesia has a small risk of adverse events. Complications, if they occur, seem minor and transient in nature. 相似文献