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31.
Dolomite is a natural mineral of great industrial importance and used worldwide, thus millions of workers are at risk of occupational exposure. Its toxicity is however, meagerly documented. In the present investigation, a dolomite powder obtained from its milling unit was analyzed by some standard methods namely, optical microscopy, transmission electron microscopy and dynamic light scattering. Results showed that dolomite powder contained particles of different shapes and size both microparticles (MPs) and nanoparticles (NPs), suggesting potential occupational exposure of these particles. An attempt was therefore, made to investigate dolomite toxicity in a particle size-dependent manner in human lung epithelial cells A(549). The comparative toxicity evaluation of MPs and NPs was carried out by assessing their effects on cell viability, membrane damage, glutathione, reactive oxygen species (ROS), lipid peroxidation (LPO), micronucleus (MN) and proinflammatory cytokines, namely tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). These markers of cytotoxicity, genotoxicity and inflammation were assayed in cells exposed to MPs and NPs in a dose-and time-dependent manner. Invariably, their toxic effects were dose-and time-dependent while NPs in general were significantly more toxic. Notably, NPs caused oxidative stress, genotoxicity and inflammatory responses, as seen by significant induction of ROS, LPO, MN, TNF-α, IL-1β and IL-6. Thus, the study tends to suggest that separate health safety standards would be required for micrometer and nanometer scale particles of dolomite.  相似文献   
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Lacerations of the Achilles tendon are caused by a number of mechanisms. The toilet seat as a cause of Achilles tendon injury is rare. We report on this rare mechanism of laceration of the tendo Achilles. The injury can be avoided with the use of western toilets and the additional devascularisation caused by extending the wound should be avoided while repairing the tendon in such situations.  相似文献   
34.
We looked at the functional outcome of 32 consecutive patients with proximal humeral fractures that required hemiarthroplasty. Functional status was assessed using University of California Los Angeles (UCLA) shoulder end result assessment, simple shoulder test (SST) and American Shoulder and Elbow Society (ASES) shoulder index. Mean age of the patients was 72.2 years and the mean follow-up was 25.3 months. The mean score on UCLA shoulder end result assessment was 24.8, the mean SST score was 7.4 and the mean ASES shoulder index was 67.2. Mean active forward elevation was 85.1°. Patient satisfaction was around 81%. Radiologically, no dislocation, loosening or greater tuberosity pull off was seen. Superior migration of the humeral head was seen in 11 patients (34%). There was no significant difference seen in functional outcome among different genders, age and those who had radiological superior migration of the prosthesis. However, there was a significant statistical difference seen in the functional outcome between patients who had a deficient or a good quality cuff showing that quality of the rotator cuff is an important predicator of functional outcome.  相似文献   
35.
This review examines the use of platelet-rich plasma (PRP) in the treatment of bone injuries and to stimulate bone formation. Studies examining both in vivo bone healing and in vitro actions of PRP on osteoblasts are reviewed. Overall, the available literature suggests that PRP does not appreciably impact bone healing or induce bone formation. However, there is some evidence to suggest that PRP might augment recruitment of osteoblast progenitors to injection sites or in sites expected to experience delayed healing. In this capacity PRP might be utilized to initiate repair of an otherwise poorly healing skeletal lesion. The demonstration that PRP is a viable therapy is hindered by a lack of standardized criteria for what constitutes PRP, and more studies are needed to compare the efficacy of PRP to that of transforming growth factor-β or platelet-derived growth factor used as sole agents.  相似文献   
36.
Objective: To determine the effectiveness of salicylic acid chemical peeling in common dermatological conditions affecting face in people with predominant Fitzpatrick skin type IV and V. Design: An interventional, quasi-experimental study. Place and Duration of Study: Military Hospital, Rawalpindi and PAF Hospital, Sargodha, from July 2002 to June 2003. Patients and Methods: A total of 167 patients of either gender, aged between 13 to 60 years, having some facial dermatoses (melasma, acne vulgaris, postinflammatory hyperpigmentations, freckles, fine lines and wrinkles, post-inflammatory scars, actinic keratoses, and plane facial warts) were included. A series of eight weekly hospital based peeling sessions was conducted in all patients under standardized conditions with 30% salicylic acid. Clinical improvement in different disorders was evaluated by change in MASI score, decrease in the size of affected area and % reduction in lesions count. McNemar test was applied for data analysis. Results: Majority of the patients showed moderate to excellent response. There was 35% to 63% improvement (p<0.05) in all dermatoses. Significant side effects, as feared in Asian skins were not observed. Conclusion: Chemical peeling with salicylic acid is an effective and safe treatment modality in many superficial facial dermatoses.  相似文献   
37.
A young girl presented with history of prolonged fever, vomiting and headache. CT scan of brain revealed a space occupying lesion in posterior cranial fossa with moderate hydrocephalus. Surgery was performed and histopathology report confirmed the lesion as tuberculous. Patient showed smooth postoperative recovery and complete remission of complaints on antituberculous treatment for one year and regular follow-up.  相似文献   
38.
Intestinal denervation contributes to enteric motor dysfunction after small bowel transplantation (SBT). Our aim was to determine long-term effects of extrinsic denervation on function of nonadrenergic, noncholinergic innervation with substance P and vasoactive intestinal polypeptide (VIP). Contractile activity of jejunal circular muscle strips from six age-matched, naive control rats (NC) and eight rats 1 year after syngeneic SBT was studied in tissue chambers. Spontaneous contractile activity did not differ between groups. Exogenous VIP inhibited contractile activity dose-dependently to a comparable degree in both groups. The VIP antagonist ([d-p-Cl-Phe6,Leu17]-VIP) and the nitric oxide synthase inhibitor l-NG-nitro-arginine did not affect VIP-induced inhibition but increased contractile activity during electrical field stimulation (EFS) in both groups. Exogenous substance P increased contractile activity dose-dependently, greater in NC than SBT. The substance P antagonist ([d-Pro2,d-Trp7,9]-substance P) inhibited effects of exogenous substance P and decreased the excitatory EFS response. Immunohistofluorescence showed tyrosine hydroxylase staining after SBT indicating sympathetic reinnervation. In jejunal circular muscle after chronic denervation, response to exogenous substance P, but not VIP, is decreased, whereas endogenous release of both neurotransmitters is preserved. Alterations in balance of excitatory and inhibitory pathways occur despite extrinsic reinnervation and might contribute to enteric motor dysfunction after SBT. Parts of this work were presented at the annual meeting of the Society for Surgery of the Alimentary Tract in Washington, DC, on May 21, 2007 and published in abstract form in Gastroenterology 2007;132:A890.  相似文献   
39.

Background

Amniotic band syndrome (ABS) is an uncommon complication of pregnancy that can result in fetal demise.

Methods

We present our experience with fetoscopic amniotic band release.

Results

Five patients underwent fetoscopic amniotic band release for preoperatively diagnosed ABS involving at least one extremity. Four of five patients were found to have involvement of the umbilical cord at the time of fetoscopy. One of these four did not have the band released and underwent fetal demise at 24 weeks. All four survivors had good functional outcomes of affected limbs. Two patients developed membrane separation and had preterm deliveries at 32 weeks gestation whereas the other two carried to term. No maternal complications were noted.

Conclusions

Fetoscopic amniotic band release is safe. Umbilical cord involvement is difficult to assess preoperatively, but when it is present should be treated to reduce the risk of fetal demise.  相似文献   
40.
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