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1.
Thalassemics require regular blood transfusion therapy leading to iron overload in the body tissues, which is a major cause of morbidity and mortality in these patients. We hereby attempted to measure this iron overload by means of exfoliative cytology, a non-invasive and inexpensive technique. The aims and objectives of our study were: 1. To detect iron overload by oral exfoliative cytology using Perl’s Prussian blue stain in β-thalassemia major patients. 2. To correlate staining positivity with serum ferritin levels. Smears were obtained from buccal mucosa of 50 β-thalassemia major patients (who had taken more than 12 transfusions) and 25 healthy subjects of the same age group as controls. Smears were stained with Perl’s Prussian blue. Blood samples were taken from the study group for estimation of serum ferritin levels. Grading criteria were defined for assessing the Prussian blue positivity. Perl’s positivity was observed in 49 out of 50 of thalassemic patients (98%). 1 patient had Grade 0, 7 patients had Grade I, 5 had Grade II, 12 had Grade III, 14 had Grade IV while 11 patients had Grade V positivity. Spearman Rank’s Correlation Co-efficient was 0.38, signifying a weak positive correlation between positivity of buccal smears for Perl’s Prussian blue staining and respective serum ferritin levels. Perl’s Prussian blue staining of exfoliated cells from buccal mucosa can be used to assess iron overload in β-thalassemia major patients, as a screening as well as diagnostic tool. With the grading system we can give a semi-quantitative assessment of the same.  相似文献   
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Background: Over one-third of the world’s population is exposed to household air pollution (HAP) but the separate effects of cooking with solid fuel and kerosene on childhood mortality are unclear.Objectives: To evaluate the effects of both solid fuels and kerosene on neonatal (0-28 days) and child (29 days-59 months) mortality.Methods: We used Demographic and Health Surveys from 47 countries and calculated adjusted relative risks (aRR) using Poisson regression models.Results: The aRR of neonatal and child mortality in households exposed to solid fuels were 1.24 (95% CI: 1.14, 1.34) and 1.21 (95% CI: 1.12, 1.30), respectively, and the aRR for neonatal and child mortality in households exposed to kerosene were 1.34 (95% CI: 1.18, 1.52) and 1.12 (95% CI: 0.99, 1.27), controlling for individual, household, and country-level predictors of mortality.Conclusions: Kerosene should not be classified as a clean fuel. Neonates are at risk for mortality from exposure to solid fuels and kerosene.  相似文献   
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Titanium carbide (TiC) reinforced nickel (Ni) matrix composites were processed via mechanical alloying (MA) followed by spark plasma sintering (SPS) process. Mechanical alloying has gained special attention as a powerful non-equilibrium process for fabricating amorphous and nanocrystalline materials, whereas spark plasma sintering (SPS) is a unique technique for processing dense and near net shape bulk alloys with homogenous microstructure. TiC reinforcement varied from 5 to 50 wt.% into nickel matrix to investigate its effect on the microstructure and mechanical behavior of Ni-TiC composites. All Ni-TiC composites powder was mechanically alloyed using planetary high energy ball mill with 400 rpm and ball to powder ratio (BPR) 15:1 for 24 h. Bulk Ni-TiC composites were then sintered via SPS process at 50 MPa pressure and 900–1200 °C temperature. All Ni-TiC composites exhibited higher microhardness and compressive strength than pure nickel due to the presence of homogeneously distributed TiC particles within the nickel matrix, matrix grain refinement, and excellent interfacial bonding between nickel and TiC reinforcement. There is an increase in Ni-TiC composites microhardness with an increase in TiC reinforcement from 5 to 50 wt.%, and it reaches the maximum value of 900 HV for Ni-50TiC composites.  相似文献   
5.
Gentamicin-induced nephrotoxicity has been well documented, although its underlying mechanisms and preventive strategies remain to be investigated. The present study was designed to investigate the protective effect of naringin, a bioflavonoid, on gentamicin-induced nephrotoxicity and to elucidate the potential mechanism. Serum specific renal function parameters (blood urea nitrogen and creatinine) and histopathology of kidney tissues were evaluated to assess the gentamicin-induced nephrotoxicity. Renal oxidative stress (lipid peroxidation, protein carbonylation, enzymatic and non-enzymatic antioxidants), inflammatory (NF-kB [p65], TNF-α, IL-6 and MPO) and apoptotic (caspase 3, caspase 9, Bax, Bcl-2, p53 and DNA fragmentation) markers were also evaluated. Significant decrease in mitochondrial NADH dehydrogenase, succinate dehydrogenase, cytochrome c oxidase and mitochondrial redox activity indicated the gentamicin-induced mitochondrial dysfunction. Naringin (100 mg/kg) treatment along with gentamicin restored the mitochondrial function and increased the renal endogenous antioxidant status. Gentamicin induced increased renal inflammatory cytokines (TNF-α and IL-6), nuclear protein expression of NF-κB (p65) and NF-κB-DNA binding activity and myeloperoxidase (MPO) activity were significantly decreased upon naringin treatment. In addition, naringin treatment significantly decreased the amount of cleaved caspase 3, Bax, and p53 protein expression and increased the Bcl-2 protein expression. Naringin treatment also ameliorated the extent of histologic injury and reduced inflammatory infiltration in renal tubules. U-HPLS-MS data revealed that naringin co-administration along with gentamicin did not alter the renal uptake and/or accumulation of gentamicin in kidney tissues. These findings suggest that naringin treatment attenuates renal dysfunction and structural damage through the reduction of oxidative stress, mitochondrial dysfunction, inflammation and apoptosis in the kidney.  相似文献   
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The integrity of the blood-brain barrier may be reflected by the blood and cerebrospinal fluid (CSF) if these two compartments are sampled at an appropriate interval after the administration of certain substances. After reading through the controversial literature, this study was undertaken to determine the frequency with which 99mTc-sodium pertechnetate entered the CSF to an abnormal extent, and to see whether this was related to any particular pathology. The plasma-to-CSF ratios were determined in 51 patients 4 hours following the intravenous administration of 0.5-10 mCi 99mTc-sodium pertechnetate. In 23 patients with active CNS tuberculosis, the mean value of the pertechnetate plasma-to-CSF ration was 32.12. In contradistinction, the plasma-to-CSF pertechnetate in 28 nontuberculous subjects was considerably higher (144.63). For the purpose of correlation, a 82Br partition test was also done on each subject 48 hours following the oral administration of NH82Br. The 48-hour study in each of these cases was generally in agreement with the pertechnetate studies: the plasma-to-CSF ratio mean value was 1.25 in patients with active CNS tuberculosis, while for the nontuberculous patients it was 3.32.  相似文献   
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The effects of intranasal administration of norethisterone (NET) on menstrual cycle length, folliculogenesis, serum levels of estradiol, FSH, LH and progesterone, vaginal cytology, cervical mucus and endometrial morphology were studied in 8 volunteers (age 28 to 39 years, weighing between 46 and 54 kg). The study period comprised 4 consecutive menstrual cycles. In the first cycle (pretreatment cycle), only the vehicle (alcohol, propylene glycol, water; 3:3:4) was sprayed intranasally (100 microliters in each nostril), using a metered nebulizer, once daily from day 3 to the last day of menstrual cycle. In the next two cycles (treatment cycles), NET (300 micrograms/day) was administered once daily, starting from day one of menstrual cycle, between 9 and 10 a.m. The fourth cycle was a post-treatment cycle in which the volunteers were monitored for recovery. Blood samples (about 5 ml each) were collected once daily from day 8 to 24 and thereafter on alternate days until the last day of cycle during all the 4 cycles. Levels of estradiol, FSH, LH and progesterone were measured in the serum samples by radioimmunoassay methods. Cervical mucus samples and vaginal smears were collected once daily starting from day 7 or 8 of each cycle until the mucus was very scanty. Serial pelvic ultrasonography was performed starting from day 7 or 8 until the growing follicle disappeared or throughout the cycle in case a growing follicular cyst was observed. Endometrial aspirates were collected once around day 22 in each cycle and processed for routine histological examination.  相似文献   
10.
Techniques of selective cannulation and sphincterotomy   总被引:4,自引:0,他引:4  
Maydeo A  Borkar D 《Endoscopy》2003,35(8):S19-S23
Selective access into the desired duct followed by incision of the sphincter, i. e. sphincterotomy, forms the cornerstone of any endoscopic intervention within the pancreaticobiliary system. The apprehensive beginner's performance and hesitance is aggravated by ignorance of ampullary anatomy and he considers selective cannulation to be the greatest hurdle. An understanding of ampullary morphology and its variations is vital in achieving selective cannulation. Technological advances have assisted in the form of development of better accessories, progressing from "immovable" catheters to movable cannulae and to single-, double-, and even triple-lumen sphincterotomes. Orientation along the long axis of the bile duct ensures access and avoids inadvertent and hazardous manipulation of the pancreatitic duct. Using guide wires, especially the 'angulated-tip' glide wire improves cannulation successs rates considerably. Precut accessotomy complements wire-guided selective cannulation, and can be used analogously to a controlled surgical incision to facilitate cannulation of the desired system after deroofing the papilla layer by layer. Published data have validated its role, demonstrating high efficacy and minimal complications when it is properly performed. Biliary sphincterotomy, using the right mode of blended current in the 11-12 o'clock direction and with the tip of the sphincterotome wire, provides a clean and bloodless splitting open of the sphincter of Oddi. Pancreatic precut, over-the-stent papillotomy and sphincterotomy over a guide wire have all been proven to be safe and effective measures, in large groups of patients. In special situations, such as where there are impacted stones or ampullary lesions, needle-knife infundibulotomy achieves reliable access. Techniques such as saline infiltration into the papilla and subtle body movements to re-position the scope enable biliary cannulation in difficult situations. Alterations in anatomy, for instance post Billroth II gastrectomy, no longer discourage the endoscopist from attempting intervention. Application of knowledge of reverse anatomy, specially designed instruments, and adherence to the proper technique improves success in these patients. Our experience of 9000 sphincterotomies over the past 12 years with minimal morbidity stands proof to the principles and techniques highlighted in this monograph. We recommend these to all aspiring endoscopists, with the assurance of improved technical success when they are implemented.  相似文献   
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