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The purpose of this study was to assess the safety and long‐term efficacy of self‐expandable stents in the treatment of benign tracheal stenosis. Nine patients (seven men) with tracheal stenosis (including one with fistula) of varied cause were treated by fluoroscopically guided balloon dilatation and stenting with self‐expandable metallic stents. The procedure was carried out under topical spray in eight patients and under general anaesthesia in one patient. The patients were followed up for a period ranging between 13 and 60 months. In eight of the nine patients, satisfactory positioning of the stent was achieved at the first instance, with immediate relief of dyspnoea. One patient with innominate artery aneurysm died 16 days after the procedure because of renal failure. At 1 month of follow up, six out of eight (75%) of our live patients were without any respiratory embarrassment. This dyspnoea‐free result reached almost 90% by the end of 1 year especially so in the fibrous strictures. Four out of the eight live patients (50%) had cough for 2 months and two (25%) had mild blood‐tinged sputum treated by inhalation and mucolytic agents. Secondary intervention was required in one patient at 1 month because of recurrent symptoms. The patient with tracheo‐oesophageal fistula required surgical intervention because of fracture of the stent. Fluoroscopically guided balloon dilatation and stenting of the tracheal stenosis is an effective non‐surgical therapy resulting in cure of fibrous strictures and palliation in cases of malignancy.  相似文献   
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The novel analogues of 5-nitrofuran-2-carboxaldehyde thiosemicarbazones 1-10 were synthesized and their copper(II) complexes 1a-10a were obtained by means of coordination with cupric chloride. All these compounds have been characterized by elemental analysis, IR, electronic spectra and thermogravimetric patterns while ligands have also been characterized by 1H NMR spectral studies. These copper complexes are bidentate and possess octahedral geometry around Cu(II) ion. Their antiamoebic activities were carried out to ascertain their effectiveness in comparison to their corresponding thiosemicarbazones. A number of these complexes possess noteworthy potencies towards HK-9 strain of Entamoeba histolytica in vitro. The complexes 2a-7a, 9a and 10a showed less IC50 value than metronidazole, the drug of choice for amoebiasis. Moreover, complexes 2a and 9a have shown the most promising antiamoebic activities (IC50 = 0.38 microM of 2a and IC50 = 0.34 microM of 9a versus IC50 = 1.81 microM of metronidazole). These results indicate that the metallated thiosemicarbazone may be lead molecule to inhibit growth of E. histolytica.  相似文献   
164.
Heterotrimeric G protein signaling is regulated by signaling modules composed of heterotrimeric G proteins, active G protein-coupled receptors (Rs), which activate G proteins, and GTPase-activating proteins (GAPs), which deactivate G proteins. We term these modules GTPase-cycle modules. The local concentrations of these proteins are spatially regulated between plasma membrane microdomains and between the plasma membrane and cytosol, but no data or models are available that quantitatively explain the effect of such regulation on signaling. We present a computational model of the GTPase-cycle module that predicts that the interplay of local G protein, R, and GAP concentrations gives rise to 16 distinct signaling regimes and numerous intermediate signaling phenomena. The regimes suggest alternative modes of the GTPase-cycle module that occur based on defined local concentrations of the component proteins. In one mode, signaling occurs while G protein and receptor are unclustered and GAP eliminates signaling; in another, G protein and receptor are clustered and GAP can rapidly modulate signaling but does not eliminate it. Experimental data from multiple GTPase-cycle modules is interpreted in light of these predictions. The latter mode explains previously paradoxical data in which GAP does not alter maximal current amplitude of G protein-activated ion channels, but hastens signaling. The predictions indicate how variations in local concentrations of the component proteins create GTPase-cycle modules with distinctive phenotypes. They provide a quantitative framework for investigating how regulation of local concentrations of components of the GTPase-cycle module affects signaling.  相似文献   
165.
15 renal transplant recipients were studied for their lipid profile. The patients were on regular post transplant follow up and had non clinical or laboratory evidence of graft dysfunction, intercurrent infection or post transplant diabetes mellitus for at least 3 months prior to the study. The mean duration of transplant was 15 ± 9.5 months (range 3-32 months). Majority (86%) were on triple immunosuppression therapy and received a mean prednisolone dose of 10.5 mg. An equal number of healthy subjects were randomly selected and studied for their lipid profile and served as control for the study group. There was no significant change in the HDL-cholesterol level as compared with controls. However, these patients showed a significantly higher LDL-cholesterol and total cholesterol levels. Further, a significant inverse correlation was observed between triglycerides and total cholesterol levels and transplant duration.Key Words: Lipid profile, Renal transplant  相似文献   
166.
A comprehensive field investigation in several parts of India has revealed that the presence of coliforms in drinking water is associated with hydrogen sulfide-producing organisms. This paper describes a simple, rapid, and inexpensive field test for the screening of drinking water for faecal pollution, based on the detection of hydrogen sulfide. The new test showed good agreement with the standard most probable number (MPN) test. It proved highly successful in the field when it was used to detect faecal pollution and to monitor water quality during an outbreak of water-borne hepatitis A infection in the city of Gwalior. The test is reliable and simple to perform, and will be especially useful for screening rural water supplies and for large-scale screening of urban water supplies where resources, time, manpower, and laboratory facilities are limited.  相似文献   
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Exposure of rats to acrylamide (ACR) caused hind limb paralysis in 58% of the animals on day 10 and decreased behavioural parameters, namely distance travelled, ambulatory time, stereotypic time and basal stereotypic movements compared with the control group. These rats also had a decrease in the reduced glutathione (GSH) content and glutathione-S-transferase (GST) activity in the corpus striatum and an increase in striatal dopamine receptors, as evident by an increase in the binding of 3H-spiperone to striatal membranes. Treatment with the ethanol:water (1:1) extract of the rhizomes of Acorus calamus (AC-002) increased the GSH content and GST activity in the corpus striatum while insignificant changes were observed in other parameters. Rats treated with ACR and AC-002 in combination had a lower incidence of paralysis (18%) compared with those treated with ACR alone on day 10 of the experiment. The rats also showed a partial recovery in other behavioural parameters. The levels of GSH content and GST activity increased in the corpus striatum, while the dopamine receptors decreased compared with the ACR treated rats. The results suggest that the neurobehavioural changes produced by ACR may be prevented following treatment with Acorus calamus rhizomes.  相似文献   
170.
A 28-year-old woman presented with pain and redness in her left eye. On examination, a free-floating cyst of size 4 mm with prominent scolex was observed in the anterior chamber. Scolex was occasionally moving in and out of its bag. To prevent the cyst migrating to the posterior chamber, pilocarpine eye drops were instilled. After 2 hours, the patient developed total pupilary block with iris bombe. The intraocular tension was 48 mm Hg. The diagnosis of cysticercosis leading to glaucoma secondary to pupilary block was made. The cyst was removed surgically by viscoexpression. The histopathology proved to be a cysticercosis.  相似文献   
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