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81.
Background: The oral route for tracheal intubation can interfere with somemaxillofacial surgical procedures. At the same time, the nasalroute can be contraindicated or impossible. Tracheostomy isthe usual solution in these circumstances, but it carries ahigh incidence of complications. We tested the submandibularroute for tracheal intubation as an alternative to tracheostomyin such situations. Methods: The procedure was performed in 13 patients suffering from panfacialfractures associated with a fracture of skull base or a displacednasal fracture, and in one patient with post-caustic burn scaraffecting most of the face including the nose and requiringa full thickness skin flap surrounding the mouth. Results: The technique was found easy and satisfactory for both the surgeonand the anaesthetist. It allowed uninterrupted surgical techniquesand a secure airway. In six of the 13 patients, the submandibulartracheal tube was left in place for up to 44 h in the intensivecare unit after the operation without complications or difficulties.Accidental dislodgement of the tube to the right main bronchusoccurred in two patients while carrying out the procedure; itwas rapidly detected and corrected. In another two patients,postoperative superficial infection occurred that respondedwell to local treatment. No other complications were encountered. Conclusions: Submandibular tracheal intubation is a simple and effectivetechnique for upper airway management in some maxillofacialsurgical patients when both oral and nasal tracheal intubationsare not convenient.  相似文献   
82.
Shilajit is a pale-brown to blackish-brown exudation, of variable consistency, exuding from layers of rocks in many mountain ranges of the world, especially the Himalayas and Hindukush ranges of the Indian subcontinent. It has been found to consist of a complex mixture of organic humic substances and plant and microbial metabolites occurring in the rock rhizospheres of its natural habitat. Shilajit has been used as a rejuvenator and an adaptogen for thousands of years, in one form or another, as part of traditional systems of medicine in a number of countries. Many therapeutic properties have been ascribed to it, a number of which have been verified by modern scientific evaluation. Shilajit has been attributed with many miraculous healing properties.  相似文献   
83.
Solid lipid nanoparticle (SLNs) formulae were utilized for the release of 5-flurouracil (5-FU) inside the colonic medium for local treatment of colon cancer. SLNs were prepared by double emulsion-solvent evaporation technique (w/o/w) using triglyceride esters, Dynasan™ 114 or Dynasan™ 118 along with soyalecithin as the lipid parts. Different formulation parameters; including type of Dynasan, soyalicithin:Dynasan ratio, drug:total lipid ratio, and polyvinyl alcohol (PVA) concentration were studied with respect to particle size and drug entrapment efficiency. Results showed that formula 8 (F8) with composition of 20% 5-FU, 27% Dynasan™ 114, and 53% soyalithicin and F14 (20% 5-FU, 27% Dynasan™ 118, and 53% soyalithicin), which were stabilized by 0.5% PVA, as well as F10 with similar composition as F8 but stabilized by 2% PVA were considered the optimum formulae as they combined small particle sizes and relatively high encapsulation efficiencies. F8 had a particle size of 402.5 nm ± 34.5 with a polydispersity value of 0.005 and an encapsulation efficiency of 51%, F10 had a 617.3 nm ± 54.3 particle size with 0.005 polydispersity value and 49.1% encapsulation efficiency, whereas formula F14 showed a particle size of 343 nm ± 29 with 0.005 polydispersity, and an encapsulation efficiency of 59.09%. DSC and FTIR results suggested the existence of the lipids in the solid crystalline state. Incomplete biphasic prolonged release profile of the drug from The three formulae was observed in phosphate buffer pH 6.8 as well as simulated colonic medium containing rat caecal contents. A burst release with magnitudes of 26%, 32% and 28.8% cumulative drug released were noticed in the first hour samples incubated in phosphate buffer pH 6.8 for both F8, F10 and F14, respectively, followed by a slow release profile reaching 50%, 46.3% and 52% after 48 hours.  相似文献   
84.
OMFS has important links with other disciplines in medicine and dentistry. Therefore it is important that people are aware of this speciality. A study was devised to determine the awareness of OMFS among the general public and to improve their understanding. A questionnaire was distributed among the participants attending a dental practice. 100 participated and the mean age was 42.5 years. Only 17% were aware of OMFS. 96% recognised the duty of OMFS practitioner while 74% did agree dual qualification was necessary. 68% identified hospital as the main place of work and 61% thought that the training was 5–6 years long.  相似文献   
85.
The first GalT gene knockout (KO) mouse model for Classic Galactosemia (OMIM 230400) accumulated some galactose and its metabolites upon galactose challenge, but was seemingly fertile and symptom free. Here we constructed a new GalT gene-trapped mouse model by injecting GalT gene-trapped mouse embryonic stem cells into blastocysts, which were later implanted into pseudo-pregnant females. High percentage GalT gene-trapped chimera obtained were used to generate heterozygous and subsequently, homozygous GalT gene-trapped mice. Biochemical assays confirmed total absence of galactose-1 phosphate uridylyltransferase (GALT) activity in the homozygotes. Although the homozygous GalT gene-trapped females could conceive and give birth when fed with normal chow, they had smaller litter size (P=0.02) and longer time-to-pregnancy (P=0.013) than their wild-type littermates. Follicle-stimulating hormone levels of the mutant female mice were not significantly different from the age-matched, wild-type females, but histological examination of the ovaries revealed fewer follicles in the homozygous mutants (P=0.007). Administration of a high-galactose (40% w/w) diet to lactating homozygous GalT gene-trapped females led to lethality in over 70% of the homozygous GalT gene-trapped pups before weaning. Cerebral edema, abnormal changes in the Purkinje and the outer granular cell layers of the cerebellum, as well as lower blood GSH/GSSG ratio were identified in the galactose-intoxicated pups. Finally, reduced growth was observed in GalT gene-trapped pups fed with normal chow and all pups fed with high-galactose (20% w/w) diet. This new mouse model presents several of the complications of Classic Galactosemia and will be useful to investigate pathogenesis and new therapies.  相似文献   
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88.
There is an increasing demand for monitoring environmental pollutants and the control requires new sensing materials with better sensitivity, selectivity and reliability. In this study, a series of Co7 clusters incorporating various flexible polyhydroxyamine ligands are explored, with the first report of thiocyanate recognition triggered by crystal formation using a Co7 crystal (1). For this, we have fortunately synthesized three new mixed metal Co7 clusters with fascinating structural features. The clusters were characterized by spectroscopic and single crystal X-ray diffraction methods and later by DFT calculations. Due to its better emission spectrum, 1 was further utilized for evaluating its sensing ability towards various anions in water. Surprisingly, 1 shows better quenching ability towards the recognition of SCN with a better binding constant. The luminescence quenching towards SCN detection was further verified by the single crystal method, HSAB principle (symbiosis) and theoretical calculations such as DFT studies. The SCXRD data clearly suggest that the Co7 (1) can be converted into Co14 (1a) by direct reaction with NaSCN under ambient conditions. Besides the soft/hard acid–base concept (symbiosis), the energies of formation, and Co–NCS and Co–OH2 bond energies (as unravelled by DFT) are responsible for this transformation. Therefore, 1 can be used as a selective and sensitive sensor for the detection of thiocyanate anions based on the fluorescence amplification and quenching method. Further, the designed cluster has also been utilized to detect anions in human blood samples to differentiate a smoker and a non-smoker. It has been concluded that the samples of smokers have a high degree of thiocyanate (∼12 or 9.5 mg L−1) in comparison to those of non-smokers (2–3 mg L−1). Thus, this kind of cluster material has high potentiality in the field of bio-medical science in future endeavours for identification of the extent of thiocyanate content in smokers.

A new Co based sensor for thiocyanate recognition by formation of the dimeric crystals is designed to distinguish a smoker from a non-smoker.  相似文献   
89.
The clinical value of PCR technology would be increased by development of improved quantitative methodology. Two new methods, electrochemiluminescence (ECL) and bioluminescence (BL), were evaluated for analytical dynamic range, sensitivity, and reproducibility of quantitation of specific DNA. The two assays were compared using an IL-2 template DNA amplified using one biotinylated forward primer and detected with sequence identical probes labeled in two different ways. PCR products were captured on streptavidin-coated plates for BL and by streptavidin-coated beads for ECL. Product detection was accomplished using either a ruthenium (ECL) or a digoxigenin-labeled probe (BL). The ECL measurement was performed using the Perkin Elmer QPCR System 5000®, while the BL methodology used a SeaLite Science AquaLite® Aequorin-antibody conjugate, which was detected with a ML3000 luminometer. Both instruments were found to be extremely sensitive with accurate quantitation of label in the attomole range, allowing detection during the exponential phase of PCR amplification. In our hands, it was possible to detect 1.5×1014 copies (18 cycles) of IL-2 PCR product using ECL and 1×1013 copies (14 cycles) using BL technology. Overall, we found the BL assay to be a rapid, sensitive, and inexpensive way to quantitate PCR-generated products with a broad range of potential analytical applications. © 1996 Wiley-Liss, Inc.  相似文献   
90.
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