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71.
To evaluate the use of cytology for the rapid detection of rectal cancer, 39 suspected cases of carcinoma of the rectum and anal canal and 7 age- and sex-matched control cases were studied by the gloved digital-scrape method. The cytologic findings were then correlated with the histopathologic diagnoses. Of 30 evaluable cases with follow-up, a correct cytologic diagnosis was made in 28 cases (93.4%), with 1 false-negative diagnosis (3.3%) and 1 false-positive diagnosis (3.3%). Gloved digital-scrape cytology is very simple, quick and inexpensive and can be carried out an out-patient basis without any complications. 相似文献
72.
Summary A detailed investigation was undertaken to examine the influence of biotin and paminobenzoic acid (PABA) in chemostat cultures of Clostridium acetobutylicum ATCC 824. Initiation of chemostat cultures with a basic synthetic medium (biotin 0.01 mg l–1; PABA 1.0 mg l–1) have resulted in a low biomass together with a low specific rate of solvent production. A different picture emerged on elevating the concentration of both vitamins 8-fold: biomass and specific rates (solvent production, glucose consumption) were increased and a solvent productivity of 2.54 g l–1 h–1 at the solvent concentration of 13.1 g l–1 was achieved. It has also been shown that PABA was the only limiting factor for the metabolism of Clostridium acetobutylicum in the basic synthetic medium and that the optimised concentration was 8 mg l–1 in the chemostat cultures with the growth conditions employed. 相似文献
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Ralph T Schermuly Soni S Pullamsetti Susanne C Breitenbach Norbert Weissmann Hossein A Ghofrani Friedrich Grimminger Sigrid M Nilius Karsten Schrör Jutta Meger-Kirchrath Werner Seeger Frank Rose 《Respiratory research》2007,8(1):4-13
Background
The rapid desensitization of the human prostacyclin (IP) in response to agonist binding has been shown in cell culture. Phosphorylation of the IP receptor by protein kinase C (PKC) has been suggested to be involved in this process.Methods and results
In this study we investigated the vasodilatory effects of iloprost, a stable prostacyclin analogue, in perfused rabbit lungs. Continuous infusion of the thromboxane mimetic U46619 was employed to establish stable pulmonary hypertension. A complete loss of the vasodilatory response to iloprost was observed in experiments with continuous iloprost perfusion, maintaining the intravascular concentration of this prostanoid over a 180 min period. When lungs under chronic iloprost infusion were acutely challenged with inhaled iloprost, a corresponding complete loss of vasoreactivity was observed. This desensitization was not dependent on upregulation of cAMP-specific phosphodiesterases or changes in adenylate cyclase activity, as suggested by unaltered dose-response curves to agents directly affecting these enzymes. Application of a prostaglandin E1 receptor antagonist 6-isopropoxy-9-oxoxanthene-2-carboxylic acid (AH 6809) or the PKC inhibitor bisindolylmaleimide I (BIM) enhanced the vasodilatory response to infused iloprost and partially prevented tachyphylaxis.Conclusion
A three-hour infusion of iloprost in pulmonary hypertensive rabbit lungs results in complete loss of the lung vasodilatory response to this prostanoid. This rapid desensitization is apparently not linked to changes in adenylate cyclase and phosphodiesterase activation, but may involve PKC function and co-stimulation of the EP1 receptor in addition to the IP receptor by this prostacyclin analogue. 相似文献75.
76.
HClO4-SiO2 catalyzed per-O-acetylation of carbohydrates 总被引:1,自引:0,他引:1
An efficient per-O-acetylation of carbohydrates catalyzed by HClO4-SiO2 is reported using a stoichiometric quantity of acetic anhydride avoiding the use of pyridine and excess acetic anhydride under solvent-free conditions. 相似文献
77.
Praveen Rai Drista Sharma Rani Soni Nazia Khatoon Bhaskar Sharma Tarun Kumar Bhatt 《Journal of microbiology (Seoul, Korea)》2017,55(4):231-236
Malaria has been present since ancient time and remains a major global health problem in developing countries. Plasmodium falciparum belongs to the phylum Apicomplexan, largely contain disease-causing parasites and characterized by the presence of apicoplast. It is a very essential organelle of P. falciparum responsible for the synthesis of key molecules required for the growth of the parasite. Indispensable nature of apicoplast makes it a potential drug target. Calcium signaling is important in the establishment of malaria parasite inside the host. It has been involved in invasion and egress of merozoites during the asexual life cycle of the parasite. Calcium signaling also regulates apicoplast metabolism. Therefore, in this review, we will focus on the role of apicoplast in malaria biology and its metabolic regulation through Ca++ signaling. 相似文献
78.
Cross-linked guar gum microspheres: A viable approach for improved delivery of anticancer drugs for the treatment of colorectal cancer 总被引:1,自引:0,他引:1
Chaurasia M Chourasia MK Jain NK Jain A Soni V Gupta Y Jain SK 《AAPS PharmSciTech》2006,7(3):E143-E151
In the present work, guar gum microspheres containing methotrexate (MTX) were prepared and characterized for local release
of drug in the colon, which is a prerequisite for the effective treatment of colorectal cancer. Guar gum microspheres were
prepared by the emulsification method using glutaraldehyde as a cross-linking agent. Surface morphological characteristics
were investigated using scanning electron microscopy. Particle size, shape, and surface morphology were significantly affected
by guar gum concentration, glutaral dehyde concentration, emulsifier concentration (Span 80), stirring rate, stirring time,
and operating temperature. MTX-loaded microspheres demonstrated high entrapment efficiency (75.7%). The in vitro drug release
was investigated using a US Pharmacopeia paddle type (type II) dissolution rate test apparatus in different media (phosphate-buffered
saline [PBS], gastrointestinal fluid of different pH, and rat cecal content release medium), which was found to be affected
by a change to the guar gum concentration and glutaraldehyde concentration. The drug release in PBS (pH 7.4) and simulated
gastric fluids followed a similar pattern and had a similar release rate, while a significant increase in percent cumulative
drug release (91.0%) was observed in the medium containing rat cecal content. In in vivo studies, guar gum microspheres delivered
most of their drug load (79.0%) to the colon, whereas plain drug suspensions could deliver only 23% of their total dose to
the target site. Guar gum microspheres showed adequate potential in achieving local release of drug in in vitro release studies,
and this finding was further endorsed with in vivo studies.
Published: September 8, 2006 相似文献
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