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51.
Objectives: To investigate the prevalence of vascular, neurological and musculoskeletal disorders of the upper limb in a group of female workers performing either mechanical or hand sanding in the furniture industry (n=100) and in a control group of female office workers (n=100). A further aim was to study the possible adverse effects of exposure to a combination of vibration and ergonomic risk factors in female workers. Methods: All female workers underwent a medical interview and a complete physical investigation. The clinical diagnoses of Raynauds phenomenon and carpal tunnel syndrome (CTS) were made according to international consensus criteria. Hand-transmitted vibration from orbital sanders was measured according to International Organization for Standardization (ISO) recommendations. Daily vibration exposure was assessed in terms of 8-h energy-equivalent frequency-weighted acceleration [A(8)] according to the European Directive on physical agents. Ergonomic load on the upper limbs was estimated by means of strain index methodology. Results: There was no significant difference in the prevalence of Raynauds phenomenon between the furniture workers (4%) and the controls (8%). The prevalence of CTS, peripheral sensorineural disturbances (after exclusion of CTS cases) and upper-limb musculoskeletal complaints was significantly greater in the furniture workers than in the controls. CTS was clinically diagnosed in 19% of the furniture workers and 8% of the controls. A log-binomial regression analysis showed that the occurrence of soft-tissue disorders of the upper limb increased significantly with the increase of both daily vibration exposure and the strain index score. It was estimated that the risk for CTS increased by a factor of 1.30 (95% CI 1.11–1.53) for each unit of increase in A(8) (ms–2), and by 1.09 (95% CI 1.02–1.15) for each unit of increase in the strain index score. Conclusions: Even though the cross-sectional design of this epidemiological study does not allow aetiological considerations, our findings suggest a significant association between occupational use of vibratory tools and soft-tissue disorders in the upper limbs of female workers. Quantitative estimation of vibration exposure and ergonomic stress showed that these physical risk factors seem to contribute in a multiplicative way to the occurrence of chronic nerve and musculoskeletal disorders in female workers operating hand-held vibrating tools in the furniture industry.  相似文献   
52.
Cyclosporin A (CsA) is an effective therapy for children with long-lasting nephrotic syndrome (NS). Long-term treatment can result in chronic CsA nephropathy (CsAN) and there is controversy concerning its incidence and severity. Trough levels are commonly used to monitor the drug concentration. We report a retrospective clinical and histological analysis of 18 children (12 males, 6 females) with steroid-dependent nephrotic syndrome (15 patients) and partially steroid-sensitive nephrotic syndrome (3 patients) treated with CsA for a long-term period (mean 4.9 years, range 2.2–6.9). Before CsA treatment all patients had normal creatinine clearance. CsA was started at a dose of 5 mg/kg per day administered orally in two divided doses and adjusted to maintain the mean CsA blood concentration between 250 and 350 ng/ml obtained from abbreviated area under the curve (AUC). A renal biopsy was performed after a mean period of 3.9 years (range 2.2–6.2) from the start of CsA treatment. Tubular, interstitial, and arteriolar lesions were evaluated in order to assess CsAN. The mean CsA dose and the mean CsA blood concentration were 4.4 mg/kg per day (range 3.6–5.8) and 276.6 ng/ml (range 162–346), respectively. No child had a worsening creatinine clearance during CsA treatment and follow-up after CsA discontinuation. If compared with the year before the start of CsA treatment, NS relapses and prednisone (PDN) dose significantly decreased during CsA treatment, 4/year versus 0.8/year (P <0.0001) and 0.9 mg/kg per day versus 0.2 mg/kg per day (P <0.0001), respectively. Histological analysis showed 15 patients with minimal change disease and 3 with focal segmental glomerulosclerosis. Clear-cut lesions diagnostic of CsAN were never found and only mild lesions were observed in 5 children (suggestive of CsAN in 2 patients and consistent with CsAN in 3 patients). Long-term CsA treatment is confirmed to be effective in preventing NS relapses and reducing PDN dose. Renal function is not a reliable indicator of CsAN. With the mean CsA blood concentrations used in our patients CsAN presented a low incidence (28%) and was generally mild. Renal biopsy should be performed 2–3 years from the start of long-term CsA treatment, especially if the mean CsA blood concentrations are not regularly monitored.  相似文献   
53.
Pancreatic lesions, particularly cysts, can simulate various diseases. We report a case of a 43-year-old woman with a large, symptomatic, retroperitoneal cyst misdiagnosed as a "renal cyst." During the retroperitoneoscopic marsupialization, the correct diagnosis of a pancreatic cyst was made, leading to an open pancreas tail resection. Histologic evaluation revealed serous cystadenoma. Especially in large retroperitoneal cysts on the left side, the correct diagnosis of a pancreatic cyst can be difficult.  相似文献   
54.
A 59-year-old woman complained of increasing pain in the left abdomen and of diarrheal symptoms after left-sided retroperitoneoscopic living donor nephrectomy. Computed tomography revealed chyloretroperitoneum. The fluid was drained percutaneously, followed by recurrent drain replacement surgery. Her diet was changed to short-chain and medium-chain fatty acids without success. After onset of dyspnea due to chylothorax, the donor underwent thoracic drainage, fully parenteral therapy, and finally somatostatin application therapy. The postoperative management of severe chylous fistula is difficult. Therefore, we recommend an early start of maximal conservative therapy. Surgical options depend on pain occurrence or mechanical problems.  相似文献   
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In cultured osteoblasts, protein kinase C (PKC) activity increases and estrogen receptor alpha (ERalpha) binding capacity decreases upon confluence. We investigated potential interactions between ERalpha and PKC isoforms and their confluence-induced modulations in clonal ROS.SMER#14 cells and primary osteoblasts. In sub-confluent ROS.SMER#14 cells, which express an exogenous plus small amounts of the endogenous ERalpha gene, the receptor appeared as two main bands of approximately 66 and approximately 46 kDa. In over-confluent, more differentiated cells, the cytosolic approximately 66 kDa ERalpha appeared decreased and the approximately 46 kDa variant increased. Enhanced expression and/or membrane translocation of PKCalpha and PKCepsilon, but not PKCzeta, was evidenced at over-confluence, along with transient increases in expression and kinase activity of c-Src, accompanied by membrane translocation of the kinase-activated enzyme. In contrast, negligible membrane translocation of PKCalpha and/or activated c-Src was observed in parental ROS 17/2.8 cells, which express low levels of full-length ERalpha. PKCalpha from over-confluent cells phosphorylated p60c-Src in vitro, suggesting functional interaction between the two kinases. ERalpha co-immunoprecipitated c-Src and PKCalpha, mostly in its cleaved form (PKMalpha). An analogous interaction was observed in primary osteoblasts. However, in these cells, much more PKCalpha/PKMalpha was ERalpha-co-immunoprecipitated at over-confluence, a condition in which the shorter, approximately 46 kDa ERalpha variant is increased. This interaction was enhanced by estradiol treatment or PKC down-regulation, but was unaffected by c-Src inhibition. These data highlight direct PKCalpha-c-Src-ERalpha interactions, which may be crucial in the modulation of estrogen responsiveness and the differentiation process in osteoblasts.  相似文献   
59.
It has been previously demonstrated that some antimicrobial agents enhance activities of human polymorphonuclear neutrophils (PMNs). The effect on the release of cytokines in an inflammatory context from PMNs by these antibiotics was evaluated. We studied the effect of the release of some cytokines by human PMNs RT-PCR analysis on a clinical strain of Klebsiella pneumoniae by comparing the effect with that observed in the presence of co-amoxiclav, sanfetrinem, clarithromycin, prulifloxacin and tobramycin. All the drugs tested were capable of modulating PMN synthesis in vitro of pro-inflammatory cytokines IL-8, IL-1beta, TNF-alpha and IL-6, but not that of anti-inflammatory cytokine IL-10. The degree of their stimulatory or inhibitory potency varied with the cytokine examined.  相似文献   
60.
Potassium channels play a crucial role in controlling the cell membrane potential. Among the different varieties of K(+) channels, the ATP-sensitive potassium channels (K(ATP) channels) have been characterized in numerous cell types, such as skeletal and smooth muscle cells, endocrine cells, cardiac cells and central neurons. Several molecules are known to activate K(ATP) channels and have been named "potassium channel openers" (PCOs). Such compounds may have a wide therapeutic potential and a few drugs are currently used as antihypertensive agents. Different chemical series of PCOs have been explored. This heterogeneous group of organic compounds comprises the benzopyran series including potent vasorelaxant drugs, such as cromakalim. The latter compound, a typical example of potassium channel opener, exerts its biological effect by activating K(ATP) channels. This review presents recent developments in the chemistry of cromakalim analoges and reports chemical aspects governing their potency and tissue selectivity.  相似文献   
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