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991.
992.
PURPOSE: The aim of this study was to evaluate whether intravitreal triamcinolone hexacetonide (TH) is a safe, longer lasting alternative to intravitreal triamcinolone acetonide (TA) in the rabbit eye. METHODS: Three groups, each comprising of 15 Dutch-belted rabbits, received a unilateral injection of 0.1 mL of drug and 0.1 mL of physiologic salt solution in the fellow eye. Group I received TA, group II received commercially available TH, and group III received reformulated iso-osmolar triamcinolone hexacetonide (rTH). Simultaneous bilateral dark-adapted electroretinography was performed following the injection. Retinal morphology was assessed by using histopathology in each group enucleated 12 weeks after injection. High-performance liquid chromatography of vitreous isolated from the enucleated eyes was used to determine drug concentrations. RESULTS: A significant reduction in saturated a-wave and maximal scotopic b-wave was observed in the group II eyes relative to the fellow control eyes at both 2 and 12 weeks postinjection (P < 0.001 for each comparison) but not in the other groups. Histopathology showed no differences between drug-injected eyes and fellow control eyes in groups I and III, but in group II there was severe degeneration of all retina layers. In group I, the drug half-life was 17.7 +/- 1.7 days, group II 44 +/- 13 days, and group III 12.8 +/- 2.3 days. CONCLUSIONS: The half-life of commercially available TH in the vitreous is double that of TA, but the former is toxic to the retina in this rabbit model. Reformulated iso-osmolar TH showed no evidence of deleterious effects to retina function or structure but had a similar half-life to TA.  相似文献   
993.
994.
In lizards, distinct patterns of the tendinous structures associated with the forearm flexors have been described. In most lizards, the m. flexor digitorum longus ends in a tendinous plate with an embedded sesamoid, from which tendons run to the terminal phalanx of each digit. This structure is known as the flexor plate. In many polychrotid lizards, however, the flexor digitorum longus muscle is continuous with individual tendons running to each digit, and no complete flexor plate is present. In most geckos, the flexor plate is reduced to a tendinous plate without sesamoid. To evaluate the consequences of these differences in morphology on locomotion and grasping, we compared the use of the fore‐arm and hand in lizards exhibiting three different tendon patterns (Pogona vitticeps, an agamid with a well‐developed flexor plate; Gekko gecko, a gekkonid with a flexor plate, but without an embedded sesamoid; Anolis equestris, a polychrotid without flexor plate, but showing independent tendons running to each digit) while moving on different substrates. We found that the presence of a flexor plate with sesamoid bone prevents digital flexion and creates a rather stiff palmar surface in P. vitticeps. This configuration makes it impossible for P. vitticeps to grasp narrow branches and results in a strongly impaired locomotor performance on narrow substrates. Both G. gecko and A. equestris can flex the palms of their hands and their fingers more extensively, and do so when moving on narrow substrates. We suggest that the reduction of the flexor plate in both G. gecko and A. equestris allows these animals to move effectively on narrow substrates. Anat Rec, 292:842–853, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
995.

Objective

To assess the impact of averaging multiple MUNIX trials on the follow-up of patients with amyotrophic lateral sclerosis (ALS).

Methods

We determined the percent relative change (%RC) of MUNIX, in healthy subjects and patients with ALS, by subtracting the MUNIX value in the second visit from the first. Both the mean of a set of three MUNIX (mean-MUNIX) and the first MUNIX sample (single-MUNIX) were evaluated. Then, we studied the sensitivity to detect relative changes over time and the statistical dispersion of the %RC from these two parameters.

Results

We found that the mean-MUNIX %RC has lower mean coefficient of variation than the single-MUNIX %RC in all muscles. The mean-MUNIX also resulted in more ALS patients with significant %RC, i.e., outside reference limits.

Conclusion

The mean-MUNIX resulted in less dispersed values of %RC in patients with ALS and thus, increased the precision of the technique. The mean-MUNIX resulted also in an increase in the sensitivity to track changes over time in these patients.

Significance

The mean-MUNIX should be considered in any ALS follow-up study as a more reliable approach and as a way of potentially reducing the sample size needed for the study.  相似文献   
996.
A rare case of hyperlipropoteinemia in a 35-day-old infant who presented not only high blood levels of cholesterol and triglycerides but also an ocular manifestation described as lipemia retinalis. The fundoscopic abnormality cleared as the levels of chilomicrons in plasma dropped. Lipemia retinalis is an important and reliable parameter of high levels of chilomicrons and triglycerides and should be considered as a significant clue while diagnosing.  相似文献   
997.

Background  

Melanoma is the most aggressive form of skin cancer and the most rapidly expanding cancer in terms of worldwide incidence. Chemotherapeutic approaches to treat melanoma have had only marginal success. Previous studies in mice demonstrated that a high diluted complex derived from Calcarea carbonica (M8) stimulated the tumoricidal response of activated lymphocytes against B16F10 melanoma cells in vitro.  相似文献   
998.
Embryos surplus to therapeutic requirements following preimplantation genetic diagnosis can be used to derive human embryonic stem cell (hESC) lines carrying mutations significant to human disease. These cells provide a powerful in vitro tool for modelling disease progression in a number of cell types as well as having the potential to revolutionise drug discovery. Robust and reproducible directed differentiation protocols are needed to maximise the potential of these cells. In this review, we explore the current use of hESC and induced pluripotent stem cells in disease-specific research and discuss the use of stem cell technology in drug discovery and toxicity testing.  相似文献   
999.

Objective

To compare procalcitonin measurements between semi-quantitative and quantitative assays.

Method

Procalcitonin was measured with the PCT-Q® and the Kryptor® assays in a pediatric emergency department.

Results

Among the 359 pairs of results, 103 had discordant results. The linear weighted kappa was 0.44 (95% CI 0.36, 0.51). The concordant/discordant results distribution varied depending on the laboratory technician (p = 0.018).

Conclusion

Agreement between procalcitonin measured semi-quantitatively and quantitatively was moderate. This is probably due to a subjective interpretation of the assay result.  相似文献   
1000.

Background:

A survey made in 1991-92, reported Sahariya, a primitive tribe of India (M. P.), having high prevalence of pulmonary tuberculosis. No follow-up study was undertaken thereafter.

Objective:

The present study was aimed to know the current status of tuberculosis (TB) in Sahariya after more than a decade of the last survey of 1991-92, as compared to that in Bhil, another primitive tribe living in the same area but never investigated for TB incidence.

Materials and Methods:

A total of 763 random sputum smears from Sahariya and 169 sputum smears from Bhil were screened for the presence of Mycobacterium tuberculosis (M..tb) in order to evaluate the prevalence of pulmonary tuberculosis in both the tribes. Chi square (χ2) statistics was performed to study the correlation between age, sex on the one hand and with the prevalence of smear-positive pulmonary TB on the other hand, if any.

Results:

In Sahariya, the prevalence of smear-positive pulmonary TB was found increased significantly (P<0.005) to 0.454 as against 0.274 estimated in the earlier survey (1991-92). Males, particularly, appeared most affected (P<0.005; 0.382), especially adults (0.260). In contrast, among Bhil, the prevalence was very low.

Conclusion:

The observed increase in TB prevalence and its gender bias in Sahariya tribe indicate the high incidence rate and faster transmission of infection, especially in male sex.  相似文献   
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