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1.
Over the years, the number of total hip replacements has been steadily increasing. Despite the improvement in surgical results, the number of claims for malpractice is higher. The primary endpoint of this work is to provide an analysis of litigation after hip replacement, to outline what are the instigating causes and costs. The secondary endpoint is to propose a possible preventive strategy for an improved care and a reduction in legal proceedings. The data of this study were collected from medical and legal files and from professional liability insurance of our institution from January 2005 to December 2016. Out of a total of 4770 THA, 40 claims were received. Peripheral nerve injuries represent the first cause of litigation (37%), followed by infectious complications, leg length discrepancy, metallosis, dislocations of the implant and a case of deep vein thrombosis. From the analysis of the past trial judgment, complications such as nerve lesions and infections are almost always recognized, as a medical error, with a high percentage of claims settled. This study shows the necessity of preventive strategies to reduce the higher number of claims for malpractice in total hip arthroplasty. Some complications such as nerve injuries and infection are frequently considered directly dependent on physician’s errors. Litigations can be reduced providing evidence of a diligent execution of the surgical procedure and of a proper postoperative management: the correct compilation of a specific informed consent and adequate doctor–patient communication.  相似文献   
2.
OBJECTIVE: To verify the feasibility and compare the results of thoracoscopic sympathectomy under local anaesthesia (LA) and spontaneous breathing vs. general anaesthesia (GA) with one-lung ventilation. METHODS: Two groups of consecutive patients underwent one stage bilateral T2-T3 thoracoscopic sympathectomy under LA (n=15) and GA (n=30) by the same surgical team for treatment of primary palmar hyperhidrosis. The groups were homogeneous for relevant demographic, physiological and clinical data, including pulmonary function. In both groups, patient's satisfaction was evaluated 24h after surgery by a simple interview and scored into five grades (1=very poor to 5=excellent), while quality of life (QOL) was evaluated by SF-36 and Nottingham's Health Profile questionnaires before and 6 months after surgery. A cost comparison between groups concerning devices, drugs, global in operating room time, medical personnel and hospital stay was also carried out. RESULTS: No operative mortality was recorded. The overall in operating room time for the whole bilateral procedure under LA was 63.55+/-10.58 vs. 86.05+/-5.75 under GA (P<0.01) and temperature increased in all patients from a baseline of 25.42+/-0.56 up to 32.15+/-0.84 degrees C. All patients undergone LA were discharged the same day after a chest roentgenogram and a short stay in the outpatient clinic. Among them three patients (20%) experienced a minimal (<30%) pneumothorax that required no treatment, while five (33.3%) had a trunk compensatory sweating that spontaneously resolved on the long run. Patients undergoing GA were discharged after a mean stay of 1.38+/-0.6 days. Among these, eight (26.6%) had prolonged trunk compensatory sweating that did not persist longer than 3 months. At a follow-up of 7.16+/-2.97 months, QOL was significantly improved with no difference between groups. The overall rate of satisfaction was greater in the LA group (P<0.05). CONCLUSIONS: In our study, awake one stage bilateral thoracoscopic sympathectomy for palmar hyperhidrosis could be safely and effectively performed as an outpatient procedure in patients refusing GA. Postoperative quality of life was equal to that in patients undergone the same procedure under GA, while patient satisfaction was better and cost were significantly reduced.  相似文献   
3.
BACKGROUND--In fibrotic diseases such as pulmonary fibrosis there is evidence suggesting enhanced synthesis and degradation of lung connective tissue components, including collagen. It has therefore been hypothesised that products of collagen degradation may have a role in the promotion of collagen deposition. In support of this hypothesis, it has recently been shown that intravenous injection of lung collagen degradation products in experimental animals stimulated collagen synthesis leading to increased collagen deposition and diffuse interstitial lung disease. METHODS--Rabbit and human fibroblast cultures from lung and skin were used as an in vitro model to study the responses of these cells to rabbit collagen degradation products. The effects of an acute exposure to collagen degradation products on synthesis of collagen and noncollagenous protein have been studied in confluent cultures by [3H]-proline incorporation. The effects of collagen degradation products on fibroblast proliferation and production of genetic types of collagen have also been investigated. RESULTS--The acute exposure of rabbit lung fibroblast cultures to collagen degradation products significantly increased collagen synthesis without affecting non-collagenous protein synthesis. This effect was dose related, specific for lung fibroblasts, and species specific. Collagen degradation products altered the rate of synthesis of genetic types of collagen with a consequent decrease of type III/I+III collagen ratio (0.26 (0.04) treated with collagen degradation products; 0.45 (0.02) controls). These effects occurred without the intervention of serum factors. In addition, collagen degradation products neither affected fibroblast proliferation nor selected specific clones emphasising one type of collagen. CONCLUSIONS--These results suggest that collagen degradation products can influence lung collagen metabolism by stimulating collagen synthesis. The regulation of collagen mass by collagen degradation products may be of importance in lung collagen homeostasis in vivo.  相似文献   
4.
Prevalence and severity of erectile dysfunction (ED) increase with aging and are often associated with illnesses, like diabetes mellitus, heart disease, and hypertension, pathologically characterized by endothelial dysfunction and whose prevalence increases with age. The assumption that ED is mainly a neurovascular disease is supported by the evidence that specific phosphodiesterase type 5 (PDE5) inhibition produces an efficient erection in a wide range of ages and conditions. The availability of specific PDE5 inhibitors has enabled the development of effective treatment strategies, in this contest, tadalafil may be considered as the least “typical” PDE5 inhibitor. In clinical trials, tadalafil significantly enhanced, in patients of different ages, all efficacy outcomes across disease etiologies and severities. With an effectiveness lasting up to 36h, tadalafil allows patients to choose when to have sexual activities without the need to time it, showing positive feedback in terms of quality of life related to the treatment. Headache and dyspepsia were the most frequent side-effects of tadalafil, followed by back pain, nasal congestion, myalgia, and flushing, but the impact that long time action could have on effectiveness and safety is not yet entirely defined. The aim of this article is to critically review the available evidence from the tadalafil clinical research program and give the physician a rational approach for intervention in the treatment of ED and related diseases.  相似文献   
5.
6.
Interactions between taste receptors in the frog tongue   总被引:4,自引:0,他引:4  
Summary Receptors sensitive to stimulation with dilute CaCl2 solutions and located in different fungiform papillae of the frog tongue are cross-connected via branches of the glossopharyngeal nerve fibers to form chemical sensory units comprising on average about 3 papillae; often one or more papillae were found to be common to different units.The receptor response observed when single papillae were individually stimulated increased, when the strength of the stimulus was raised, at a much lower rate than that obtained by stimulating the whole tongue surface. This proves that the antidromic impulses travelling in the cross-connections linking different papillae result in an evident depression of the receptor response to CaCl2.The possible functional significance of mutual interaction between the receptors in the frog tongue is discussed.This study was supported by grants from the Consiglio Nazionale delle Ricerche (Impresa di Elettrofisiologia) of Rome, Italy.  相似文献   
7.
Soft tissue tumors commonly show cytogenetic abnormalities, some of which are tumor specific. Lipomatous tumors represent the largest category of soft tissue neoplasms, and numerous karyotypic aberrations have been identified. However, clear-cut correlation between morphology and karyotype has not been undertaken on a systematic basis in a double-blind setting. The morphological features and histological diagnosis of 178 lipomatous neoplasms were reviewed independently without knowledge of the clinical data. The consensus diagnoses were then correlated with the clinical findings and compared with the tumors' karyotypes, using G-banded preparations from short-term cultures. The data were collated by a multicenter collaborative group of pathologists, geneticists, and surgeons. Clonal chromosomal abnormalities were identified in 149 cases studied (84%) and, to a large extent, the karyotype correlated with the morphological diagnosis. Specifically, 26 (96%) of 27 myxoid liposarcomas and its poorly differentiated variants showed a t(12;16); 29 (78%) of 37 atypical lipomatous tumors (including 5 dedifferentiated cases) showed ring chromosomes; 74 (80%) of 93 subcutaneous and intramuscular lipomas had karyotypic aberrations affecting mainly 12q, 6p, and 13q; 7 of 8 spindle cell and pleomorphic lipomas had aberrations of 16q; 3 lipoblastomas showed 8q rearrangements; and 2 hibernomas showed 11q abnormalities. We conclude that cytogenetic abnormalities are common in lipomatous tumors, correlate reliably with morphological sub-type in many cases, and can be of diagnostic value in histologically borderline or difficult cases.  相似文献   
8.
Nitric oxide (NO) is a candidate retrograde messenger in long-term potentiation (LTP). The NO metabolic pathway is expressed in the cerebellar granule cell layer but its physiological role remained unknown. In this paper we have investigated the role of NO in cerebellar mossy fiber-granule cell LTP, which has postsynaptic N-methyl-d-aspartate (NMDA) receptor-dependent induction. Pre- and postsynaptic current changes were simultaneously measured by using extracellular focal recordings, and NO release was monitored with an electrochemical probe in P21 rat cerebellar slices. High-frequency mossy fiber stimulation induced LTP and caused a significant NO release (6.2 +/- 2.8 nM; n = 5) in the granular layer that was dependent on NMDA receptor as well as on nitric oxide synthase (NOS) activation. Preventing NO production by perfusing the NOS inhibitor 100 microM NG-nitro-l-arginine (L-NNA), blocking extracellular NO diffusion by 10 microM MbO2, or inhibiting the NO target guanylyl cyclase (sGC) with 10 microM 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-dione (ODQ) prevented LTP. Moreover, the NO donor 10 microM 2-(N,N-diethylamino)-diazenolate-2-oxide.Na (DEA-NO) induced LTP, which was mutually occlusive with LTP generated by high-frequency stimulation, prevented by ODQ, and insensitive to NMDA channel blockade (50 microM APV + 25 microM 7-Cl-kyn) or interruption of mossy fiber stimulation. Thus NO is critical for LTP induction at the cerebellar mossy fiber-granule cell relay. Interestingly, LTP manipulations were accompanied by consensual changes in the presynaptic current, suggesting that NO acts as a retrograde signal-enhancing presynaptic terminal excitability.  相似文献   
9.
The nosologic status of fibrous dysplasia (FD), a well-known and relatively common bone lesion, is controversial. Information collected by the CHromosomes And MorPhology (CHAMP) study group on published and unpublished cases of fibrous dysplasia shows the presence of clonal chromosome changes in at least a proportion of these lesions. The chromosome aberrations found in FD lesions have been quite variable and have included both structural and numerical changes. Two of the three cases investigated at the study group had trisomy 2 as the sole acquired anomaly. Combined with previously published data, +2 and rearrangements involving chromosome band 12p13 have each been detected in 3 of 8 cases with abnormal karyotype of 11 in which chromosomal analysis has been performed, suggesting that FD is a neoplastic lesion rather than a "dysplastic" process, as has been generally believed and as implied by its very name.  相似文献   
10.
 Ca2+ channel modulation by the μ opioid agonist [d-Ala2, N-Me-Phe4, Gly5-ol]-enkephalin (DAGO) and the δ opiate agonists [d-Pen2, d-Pen5]-enkephalin (DPDPE) and [d-Ala2, d-Leu5]-enkephalin (DADLE) in cultured human neuroblastoma SH-SY5Y cells was investigated using the whole-cell variant of the patch-clamp technique. In SH-SY5Y cells, differentiated in vitro with retinoic acid, all agonists reversibly decreased high-voltage-activated, ω-conotoxin-sensitive Ba2+ currents in a concentration-dependent way. Inhibition was maximal with a 1 μM concentration of opiate agonists (76% with DAGO and 63% with δ agonists, when measured at 0 mV) and was characterized by a clear slow down of Ba2+ current activation at low test potentials. Both inhibition and slow down of activation were attenuated at more positive potentials, and could be partially relieved by strong conditioning depolarizations. Current suppression operated by both μ and δ agonists was prevented by pre-treatment of the cells with pertussis toxin. No sign of additivity was observed when δ agonists were applied to cells that were maximally activated by DAGO, suggesting that a common mechanism, involving the same type of modulating molecule, is responsible for Ca2+ channel inhibition promoted by activation of μ and δ opioid receptors in SH-SY5Y cells. Received: 10 October 1996 / Received after revision and accepted: 18 November 1996  相似文献   
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