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61.
62.
Excision of the submandibular gland by an intraoral approach   总被引:3,自引:0,他引:3  
To improve the outcome in patients with benign diseases of the submandibular gland, we have developed an entirely intraoral technique for excision of the submandibular gland. This procedure is anatomically safe and can be performed with minimal morbidity. We believe the essential surgical steps are as follows: (1) infiltration with Xylocaine plus epinephrine with an adequate waiting period for hemostasis; (2) careful identification of the submandibular duct/lingual nerve relationship; (3) anterior retraction of the mylohyoid muscle to expose the superficial lobe; (4) superiorly directed, extraoral, manipulation of the submandibular gland; and (5) close and blunt dissection to the gland laterally to avoid injury to the facial artery and vein.  相似文献   
63.
Joint moment estimation using the traditional inverse dynamics analysis presents two challenging problems, which limit its reliability. First, the quality of the computed moments depends directly on unreliable estimates of the segment accelerations obtained numerically by differentiating noisy marker measurements. Second, the representation of joint moments from combined video and force plate measurements belongs to a class of ill-posed problems, which does not possess a unique solution. This paper presents a well-posed representation derived from an embedded constraint equation. The proposed method, referred to as the embedded constraint representation (ECR), provides unique moment estimates, which satisfy all measurement constraints and boundary conditions and require fewer acceleration components than the traditional inverse dynamics method. Specifically, for an n-segment open chain planar system, the ECR requires n-3 acceleration components as compared to 3(n-1) components required by the traditional (from ground up) inverse dynamics analysis. Based on a simulated experiment using a simple three-segment model, the precision of the ECR is evaluated at different noise levels and compared to the traditional inverse dynamics technique. At the lowest noise levels, the inverse dynamics method is up to 50 percent more accurate while at the highest noise levels the ECR method is up to 100 percent more accurate. The ECR results over the entire range of noise levels reveals an average improvement on the order 20 percent in estimating the moments distal to the force plate and no significant improvement in estimating moments proximal to the force plate. The new method is particularly advantageous in a combined video, force plate, and accelerometery sensing strategy.  相似文献   
64.
We have shown previously that the glucagon-like peptide-1 (GLP-1)-(7-36) amide increases myocardial glucose uptake and improves left ventricular (LV) and systemic hemodynamics in both conscious dogs with pacing-induced dilated cardiomyopathy (DCM) and humans with LV systolic dysfunction after acute myocardial infarction. However, GLP-1-(7-36) is rapidly degraded in the plasma to GLP-1-(9-36) by dipeptidyl peptidase IV (DPP IV), raising the issue of which peptide is the active moiety. By way of methodology, we compared the efficacy of a 48-h continuous intravenous infusion of GLP-1-(7-36) (1.5 pmol.kg(-1).min(-1)) to GLP-1-(9-36) (1.5 pmol.kg(-1).min(-1)) in 28 conscious, chronically instrumented dogs with pacing-induced DCM by measuring LV function and transmyocardial substrate uptake under basal and insulin-stimulated conditions using hyperinsulinemic-euglycemic clamps. As a result, dogs with DCM demonstrated myocardial insulin resistance under basal and insulin-stimulated conditions. Both GLP-1-(7-36) and GLP-1-(9-36) significantly reduced (P < 0.01) LV end-diastolic pressure [GLP-1-(7-36), 28 +/- 1 to 15 +/- 2 mmHg; GLP-1-(9-36), 29 +/- 2 to 16 +/- 1 mmHg] and significantly increased (P < 0.01) the first derivative of LV pressure [GLP-1-(7-36), 1,315 +/- 81 to 2,195 +/- 102 mmHg/s; GLP-1-(9-36), 1,336 +/- 77 to 2,208 +/- 68 mmHg] and cardiac output [GLP-1-(7-36), 1.5 +/- 0.1 to 1.9 +/- 0.1 l/min; GLP-1-(9-36), 2.0 +/- 0.1 to 2.4 +/- 0.05 l/min], whereas an equivolume infusion of saline had no effect. Both peptides increased myocardial glucose uptake but without a significant increase in plasma insulin. During the GLP-1-(9-36) infusion, negligible active (NH2-terminal) peptide was measured in the plasma. In conclusion, in DCM, GLP-1-(9-36) mimics the effects of GLP-1-(7-36) in stimulating myocardial glucose uptake and improving LV and systemic hemodynamics through insulinomimetic as opposed to insulinotropic effects. These data suggest that GLP-1-(9-36) amide is an active peptide.  相似文献   
65.
BackgroundFor radioimmunotherapy purposes, a chemical complex with high absorption in cancer tumor is required. New chemicals are to be examined for their concentration in tumor and healthy organs. These are labeled with β-emitting radioisotopes to irradiate the tumor while deposited inside it.AimTo study the capability of recently developed chemical complex in targeting cancer tumor and investigate the distribution of 153Sm-TPTTC in rat organs as function of time.Materials and methodsThe chemical complex – [Tris(1,10-phenanthroline)Samarium(III)] trithiocyanate was prepared and labeled with 153Sm radioisotope. The labeled complex was injected to a population of tumor bearing mice. In 2, 4, 24, 48, 96 h after injection the animals were sacrificed and the concentration of Samarium complex was measured in various organs such as blood, heart, intestine, colon, liver, spleen, kidney, sternum and bone.ResultsThe concentration of the radiopharmaceutical in various organs was measured at different times. The temporal behavior of biodistribution of 153Sm-TPTTC was modeled and drawn as function of time.ConclusionIt is shown that 153Sm-TPTTC is concentrated in tumor tissue and liver much more than in other organs. The variation of pharmaceutical concentration in all organs is described with summation of eight exponential terms and it approximates our experimental data with precision better than 2%.  相似文献   
66.
Aggregations of fungiid corals are common on Indo-Pacific reefs, but visible signs of direct competition are uncommon. Although negative interactions between fungiids are generally thought to be negligible, the results of an experiment manipulating aggregation and species identity indicated that per capita calcification rates of Fungia concinna were depressed when surrounded by five other Fungia. The reduction in growth did not vary if neighbors were Fungia concinna or Fungia paumotensis, suggesting that these two related species overlap substantially in their competitive impacts. However, mucus production and movement occurred more frequently in heterospecific than conspecific groups. These results suggest that there is a cost to group living, but depressed growth must be weighed against the potential benefits of successful spawning in conspecific aggregations. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Communicated by Ecology Editor Professor Peter Mumby  相似文献   
67.

S3E3 is a new variant of S3 antimicrobial peptide (AMP) derived from factor C of horseshoe hemolymph and features a high binding affinity for endotoxin. In this research, site-specific conjugated S3E3 AMP onto Sepharose 6% solid phase support (S3E3-S-Sepharose) was applied for endotoxin removal from protein solutions. The bovine serum albumin (BSA) was chosen as a protein model due to its acidic-sticky nature interfering with the endotoxin removal process. The batch process parameters including, endotoxin concentration, pH, and ionic strength of the sample were optimized by response surface methodology to reach maximum endotoxin binding capacity and protein recovery. The predicted optimal conditions for enhanced endotoxin removal performance were as follows: pH 4.5, 25 mM NaCl, and 68,500 EU/ml endotoxin leading to a maximum endotoxin binding capacity of 3.114?×?10+6 EU/ml of resin and a 95.89% protein recovery. S3E3-S-Sepharose could be applied as an efficient endotoxin removal affinity chromatography matrix at downstream processes of recombinant therapeutics due to its high capacity and protein recovery.

  相似文献   
68.
Various retinal degenerative disorders manifest in alterations of the AKT/mTOR axis. Despite this, consensus on the therapeutic targeting of mTOR in degenerating retinas has not yet been achieved. Therefore, we investigated the role of AKT/mTOR signaling in rd16 retinas, in which we restored the AKT/mTOR axis by genetic ablation of pseudokinase TRB3, known to inhibit phosphorylation of AKT and mTOR. First, we found that TRB3 ablation resulted in preservation of photoreceptor function in degenerating retinas. Then, we learned that the mTOR downstream cellular pathways involved in the homeostasis of photoreceptors were also reprogrammed in rd16 TRB3−/− retinas. Thus, the level of inactivated translational repressor p-4E-BP1 was significantly increased in these mice along with the restoration of translational rate. Moreover, in rd16 mice manifesting decline in p-mTOR at P15, we found elevated expression of Beclin-1 and ATG5 autophagy genes. Thus, these mice showed impaired autophagy flux measured as an increase in LC3 conversion and p62 accumulation. In addition, the RFP-EGFP-LC3 transgene expression in rd16 retinas resulted in statistically fewer numbers of red puncta in photoreceptors, suggesting impaired late autophagic vacuoles. In contrast, TRIB3 ablation in these mice resulted in improved autophagy flux. The restoration of translation rate and the boost in autophagosome formation occurred concomitantly with an increase in total Ub and rhodopsin protein levels and the elevation of E3 ligase Parkin1. We propose that TRB3 may retard retinal degeneration and be a promising therapeutic target to treat various retinal degenerative disorders.Subject terms: Translation, Diseases  相似文献   
69.
We provide cytochrome c oxidase subunit 1 (COI) barcode sequences of fishes of the Nayband National Park, Persian Gulf, Iran. Industrial activities, ecological considerations and goals of The Fish Barcode of Life campaign make it crucial that fish species residing in the park be identified. To the best of our knowledge, this is the first report of barcoding data on fishes of the Persian Gulf. We examined 187 individuals representing 76 species, 56 genera and 32 families. The data flagged potentially cryptic species of Gerres filamentosus and Plectorhinchus schotaf. 16S rDNA data on these species are provided. Exclusion of these two potential cryptic species resulted in a mean COI intraspecific distance of 0.18%, and a mean inter- to intraspecific divergence ratio of 66.7. There was no overlap between maximum Kimura 2-parameter distances among conspecifics (1.66%) and minimum distance among congeneric species (6.19%). Barcodes shared among species were not observed. Neighbour-joining analysis showed that most species formed cohesive sequence units with little variation. Finally, the comparison of 16 selected species from this study with meta-data of conspecifics from Australia, India, China and South Africa revealed high interregion divergences and potential existence of six cryptic species. Pairwise interregional comparisons were more informative than global divergence assessments with regard to detection of cryptic variation. Our analysis exemplifies optimal use of the expanding barcode data now becoming available.  相似文献   
70.

Background

Serum albumin is a major transport protein in mammals and is known to have at least seven binding sites for long-chain fatty acids (FAs).

Scope of review

We have devised a new electron paramagnetic resonance (EPR) spectroscopic approach to gain information on the functional structure of serum albumin in solution in a “coarse-grained” manner from the ligands' point of view. Our approach is based on using spin labeled (paramagnetic) stearic acids self-assembled with albumin and subsequent nanoscale distance measurements between the FAs using double electron–electron resonance spectroscopy (DEER). Simple continuous wave (CW) EPR spectroscopy, which allows for quantification of bound ligands, complements our studies.

Major conclusions

Based on DEER nanoscale distance measurements, the functional solution structure of human serum albumin (HSA) has remarkably been found to have a much more symmetric distribution of entry points to the FA binding sites than expected from the crystal structure, indicating increased surface flexibility and plasticity for HSA in solution.In contrast, for bovine serum albumin (BSA), the entry point topology is in good agreement with that expected from the crystal structure of HSA. Changes in the solution structures between albumins can hence be revealed and extended to more albumins to detect functional differences at the nanoscale.Going beyond fundamental structural studies, our research platform is also excellently suited for general studies of protein–solvent interactions, temperature effects and ligand binding.

General significance

We discuss how our research platform helps illuminate protein dynamics and function and can be used to characterize albumin-based hybrid materials. This article is part of a Special Issue entitled Serum Albumin.  相似文献   
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