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71.
This study evaluated the pony as a potentially suitable model for vascular implant research. Healthy, conditioned ponies were randomly assigned to one of three groups: group I, carotid artery autografts (n = 6); group II, e-PTFE carotid interpositional grafts (n = 5); and group III, e-PTFE carotid interpositional grafts plus aspirin (10 mg/kg) and dipyridamole (3.5 mg/kg) drug administration. It was found that autografts remained patent longest (mean = 396.2 days; grafts were still patent at time of writing) followed by group III grafts (157.5 days), with group II grafts remaining patent for the shortest duration (61.1 days), (p less than 0.01). Patency was determined using two-dimensional real-time ultrasonography with Doppler velocimetry and/or arteriography. It was demonstrated that the pony's response to antithrombotic drugs was consistent and comparable to that in other animal models, both with respect to platelet function and affect on patency rate. The combination of the ease of surgical manipulation, drug administration, and platelet function testing, the comparable size of the pony and its heart and blood vessels to that of an adult human, the long life span of ponies, and the patency results of this study have demonstrated that the pony is a valuable animal model for vascular research.  相似文献   
72.
In this study, the commonest malignancy was supraglottic carcinoma (12 of 17 cass). Mostly (94%) our patients were males. Histologically moderate or poorly differentiated squamous cell carcinoma was the commonest tumour. Thirteen of 17 (76%) cases had secondaries in neck and bilateral secondaries were seen only in supraglottic carcinomas. Cases with post cricoid involvement (absent laryngeal crepitus) had metastasis in neck in 90% of cases. DIMCB and PHA skin reactivity did not reveal any difference between the cases with secondary tumours and those without secondaries in neck (P>0.05). Absolute lymphocyte count (A.L.C.) was found to be significantly increased in the former group (P<0.05).  相似文献   
73.
Mothers of 62 infants on apnea monitors (M) and 72 nonmonitored (NM) infants completed questionnaires describing their anxiety upon leaving the hospital, at 1 to 3 month follow-up, and at postmonitoring (or 3 to 6 month followup) A modified version of the Start-Trait Anxlety lnterval (STAI) assessed general (trait) anxlety as well as anxiety in two situations infant sleepmg with parents and infant sleeping alone Both NM and M mothers reported high anxiety about infant sleeping alone, while M mothers reported higher anxiety than NM mothers about the infant sleeping alone No differences in trait anxiety were observed lnterpretation was qualified due to initial group differences in demographics.  相似文献   
74.

Background:   

The early diagnosis of tuberculous meningitis (TBM) is very crucial, since delayed diagnosis can lead to various neurological manifestations. We have previously developed an in-house indirect enzyme-linked immunosorbent assay (ELISA) for TBM diagnosis using the Antigen 85 (Ag 85) complex. It has been suggested that the Ag 85 complex might give false-positive reactions for individuals vaccinated with Bacillus Calmette-Guérin (BCG).  相似文献   
75.
Making hand-assisted laparoscopy easier: preventing CO2 leak.   总被引:2,自引:0,他引:2  
Hand assistance has been a significant advance in making laparoscopy an easier and safer method for certain procedures such as nephrectomy. The value of this technique is realized when comparing patient outcomes (e.g., less postoperative pain, shorter hospital stay, quicker recovery time) with those of the standard open approaches. One reported disadvantage of the Pneumo Sleeve device for hand-assisted laparoscopy is leakage of CO2 gas from around the ring base. We describe in detail our technique to secure the Pneumo Sleeve to the abdomen in such a way as to prevent leakage of intraperitoneal gas and fluid.  相似文献   
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Three amphiphilic random copolymers poly(2-(dimethylaminoethyl)methacrylate-co-alkylacrylate) (where, alkyl = hexyl, octyl, dodecyl) with 16 mol% hydrophobic substitution were synthesized. Surface tension, viscosity, fluorescence probe, dynamic light scattering (DLS), as well as transmission electron microscopic (TEM) techniques were utilized to investigate self-assembly formation by the hydrophobically modified polymers (HMPs) in pH 5. Formation of hydrophobic domains through inter-polymer chain interaction of the copolymer in dilute solution was confirmed by fluorescence probe studies. Average hydrodynamic diameter of the copolymer aggregates at different polymer concentration was measured by DLS studies. The copolymer with shorter hydrophobic chain exhibits larger hydrodynamic diameter in dilute solution, which decreased with either increase of concentration or increase of hydrophobic chain length. TEM images of the dilute solutions of the copolymers with shorter as well as with longer hydrophobic chain exhibit spherical aggregates of different sizes. The antimicrobial activity of the copolymers was evaluated by measuring the minimum inhibitory concentration value against one Gram-positive bacterium Bacillus subtilis and one Gram-negative bacterium Escherichia coli. The copolymer with the octyl group as pendent hydrophobic chain was found to be more effective in killing these microorganisms. The interaction of the cationic copolymers with calf-thymus DNA was studied by fluorescence quenching method. The polymer-DNA binding was found to be purely electrostatic in nature. The hydrophobes on the polymer backbone were found to have a significant influence on the binding process. Biocompatibility studies of the copolymers in terms of cytotoxicity measurements were finally performed at different concentrations of the HMPs to evaluate their potential application in biomedical fields.  相似文献   
79.
This summary workshop report highlights presentations and over-arching themes from an October 2011 workshop. Discussions focused on best practices in the application of biopharmaceutics in oral drug product development and evolving bioequivalence approaches. Best practices leverage biopharmaceutic data and other drug, formulation, and patient/disease data to identify drug development challenges in yielding a successfully performing product. Quality by design and product developability paradigms were discussed. Development tools include early development strategies to identify critical absorption factors and oral absorption modeling. An ongoing theme was the desire to comprehensively and systematically assess risk of product failure via the quality target product profile and root cause and risk analysis. However, a parallel need is reduced timelines and fewer resources. Several presentations discussed applying Biopharmaceutics Classification System (BCS) and in vitro-in vivo correlations in development and in post-development and discussed both resource savings and best scientific practices. The workshop also focused on evolving bioequivalence approaches, with emphasis on highly variable products (HVDP), as well as specialized modified-release products. In USA, two bioequivalence approaches for HVDP are the reference-scaled average bioequivalence approach and the two-stage group-sequential design. An adaptive sequential design approach is also acceptable in Canada. In European Union, two approaches for HVDP are a two-stage design and an approach to widen C (max) acceptance limits. For some specialized modified-release products, FDA now requests partial area under the curve. Rationale and limitations of such metrics were discussed (e.g., zolpidem and methylphenidate). A common theme was the benefit of the scientific and regulatory community developing, validating, and harmonizing newer bioequivalence methodologies (e.g., BCS-based waivers and HVDP trial designs).  相似文献   
80.
Researchers have recently demonstrated the presence of anti-HIV-1 microRNAs (miR-28, miR-125b, miR-150, miR-223, and miR-382) in monocytes, macrophages, and CD4+ T cells, which are the primary targets of HIV infection. These miRNAs appear to regulate the level of infectivity of HIV-1 in the target cells, and thus have an impact on HIV-1 latency. The levels of these miRNAs are significantly higher in resting CD4+ T cells than those in active CD4+ T cells, whereas HIV-1 infectivity is greater in active than in resting CD4+ T cells. Similarly, the levels of these miRNAs are significantly higher in monocytes than in macrophages, whereas HIV-1 infectivity is greater in macrophages than in monocytes. Down-regulation or inhibition of the activity of these miRNAs can promote replication of latent HIV-1 in resting CD4+ T cells and in monocytes. Recently, morphine was shown to down regulate the expression of anti-HIV miRNAs (miRNA-28, 125b, 150, and 382) in cultured human monocytes and this effect of morphine was mediated via activation of mu opioid receptors (MOR). In addition, levels of these anti-HIV miRNAs were significantly lower in the peripheral blood mononuclear cells (PBMCs) isolated from heroin-dependent subjects than those from control subjects. These findings raise an important question: Does morphine have potential to activate latent HIV-1 in resting CD4+ T cells and macrophages, including microglia of human subjects maintained on highly active antiretroviral therapy (HAART)? Further research is required to answer this question.  相似文献   
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