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131.
Metabolic Brain Disease - Acetylcholine is an excitatory neurotransmitter that modulates synaptic plasticity and communication, and it is essential for learning and memory processes. This...  相似文献   
132.
The objective of this study was to evaluate the infectivity of Toxocara canis eggs after interacting with isolated nematophagous fungi of the species Duddingtonia flagrans (AC001) and Pochonia chlamydosporia (VC4), and test the predatory activity of the isolated AC001 on T. canis second stage larvae after 7 days of interaction. In assay A, 5000 embryonated T. canis eggs previously in contact with the AC001 and VC4 isolated for 10 days were inoculated into domestic chickens (Gallus gallus domesticus), and then these animals were necropsied to collect material (digested liver, intestine, muscles and lungs) at 3-, 7-, 14-, and 21-day intervals after inoculation. In assay A, the results demonstrated that the prior interaction of the eggs with isolated AC001 and VC4 decreases the amount of larvae found in the collected organs. Difference (p?<?0.01) was observed in the medium larvae counts recovered from liver, lung, intestine, and muscle of animals in the treated groups when compared to the animals in the control group. At the end of assay A, a percentage reduction of 87.1 % (AC001) and 84.5 % (VC4) respectively was recorded. In the result of assay B, the isolated AC001 showed differences (p?<?0.01) compared to the control group, with a reduction of 53.4 % in the recovery of L2. Through these results, it is justified to mention that prior interaction of embryonated T. canis eggs with the tested fungal isolates were efficient in reducing the development and migration of this parasite, in addition to the first report of proven predatory activity on L2.  相似文献   
133.
Crystallization elution fractionation (CEF) is a relatively new polyolefin characterization technique used to estimate the chemical composition distribution (CCD) of semicrystalline copolymers. CEF is developed to enhance the resolution and reduce the analysis time of temperature rising elution fractionation (TREF) by separating polymer samples in both the crystallization and elution steps. A model based on the concept of population balance, crystallization/dissolution kinetics, and dispersion model is developed to understand the CEF fractionation mechanisms. The proposed CEF model is found to describe well the experimental CEF profiles of a series of ethylene/1‐octene copolymers with different comonomer contents.

  相似文献   

134.
BACKGROUND: The clinical behavior of colorectal carcinoma is highly variable without reliable predictive biomarkers. Previous reports have shown that flow cytometric DNA analysis may provide valuable prognostic information in these tumors. PURPOSE AND METHODS: This study evaluates the DNA ploidy and the S-phase fraction (SPF) on frozen samples obtained from 61 patients with colorectal carcinoma by using flow cytometry, and it correlates the data with histopathologic features known to affect disease prognosis. Tumors were classified using the World Health Organization's histologic criteria and were staged according the American Joint Committee on Cancer's classification system. Grade of the neoplasm, vascular invasion, and perineural tumor spread were evaluated in every case. RESULTS: Fifty-nine percent of tumors were aneuploid and showed statistically significant higher S-phase values than diploid tumors (22.5 vs. 11.2 percent; P < 0.00001). Mean SPF of the whole series was 17.9 (range, 4.2–44.2) percent. A statistically significant association was found between SPF values and histologic grade (P < 0.0016), nodal status (P <0.0007), distant metastasis(P < 0.0001), tumor stage (P <0.0001), venous invasion (P < 0.0002), and lymphatic permeation (P < 0.01) but not with perineural growth and infiltration of the neoplasm through the bowel wall (T). DNA ploidy correlated positively with tumor stage (P <0.03), and the association between aneuploidy and advanced stages of the disease was statistically significant. CONCLUSIONS: These findings showed that flow cytometric DNA ploidy and SPF, evaluated in fresh samples, are potentially useful parameters to estimate colorectal carcinoma biopathology. Aneuploidy and high replicative neoplastic activity correlated with histopathologic features that are commonly associated with the prognosis of colorectal carcinoma, being SPF-related to disease dissemination and, therefore, an indicator of clinical relevance.  相似文献   
135.
The male mongoose is a seasonal breeder and displays a distinct seasonal pattern in serum androgen levels. In this series of experiments testicular responsiveness to luteinizing hormone (LH) was evaluated during the breeding (active) and inactive seasons. The responsiveness of testes to LH was assessed by measuring [125I]hCG (human chorionic gonadotropin) binding to dispersed interstitial cells and by measuring in vitro LH-stimulated androgen release by dispersed interstitial cells. The binding data indicated that there was a significantly greater concentration of LHhCG binding sites/Leydig cell during the active season than during the inactive season. In contrast, dispersed interstitial cells prepared from animals trapped during the active and inactive seasons were equally responsive to small doses (“physiological”) of ovine LH (oLH); however, higher doses of oLH produced a significant depression in the interstitial cell output of androgen during the inactive season but not during the active season. These results indicate that there are seasonal differences in the responses of the testis to LH. Whether the seasonal pattern of serum androgen levels in the male mongoose is directed by seasonal changes in serum gonadotropin levels or changes in testicular responsiveness to LH is discussed.  相似文献   
136.
137.
Fibroblasts constitute a dynamic and versatile population of cells of mesenchymal origin, implicated in both regenerative strategies and pathological conditions. Despite being frequently associated to disease development, particularly through the establishment of fibrotic tissue, fibroblasts hold great potential for tissue engineering and regenerative medicine applications. They are responsible for synthesizing and depositing extracellular matrix components, allowing other cells to settle and migrate along a three‐dimensional support and thereby generating an organ‐specific architecture. Additionally, they produce bioactive molecules that are involved in several physiological processes, including angiogenesis and tissue repair. Although there seems to be much still to unveil about these fascinating cells they have been attracting increasing interest and are now being intensively explored as a cell source to develop bioengineered tissue constructs or to improve stem cell‐based technologies. This review intends to highlight the potential of fibroblasts in orchestrating tissue regeneration, as well as to contribute to uncover uncharted prospective applications of these cells. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
138.

Objective

To identify potential prognostic factors that may predict clinical improvement of patients treated with different physical therapy interventions in the short-term.

Methods

This is a prospective cohort study. A total of 616 patients with chronic non-specific low back pain treated with interventions commonly used by physical therapists were included. These patients were selected from five randomized controlled trials. Multivariate linear regression models were used to verify if sociodemographic characteristics (age, gender, and marital status), anthropometric variables (height, body mass, and body mass index), or duration of low back pain, pain intensity at baseline, and disability at baseline could be associated with clinical outcomes of pain intensity and disability four weeks after baseline.

Results

The predictive variables for pain intensity were age (β = 0.01 points, 95% CI = 0.00 to 0.03, p = 0.03) and pain intensity at baseline (β = 0.23 points, 95% CI = 0.13 to 0.33, p = 0.00), with an explained variability of 4.6%. Similarly, the predictive variables for disability after four weeks were age (β = 0.03 points, 95% CI = 0.00 to 0.06, p = 0.01) and disability at baseline (β = 0.71 points, 95% CI = 0.65 to 0.78, p = 0.00), with an explained variability of 42.1%.

Conclusion

Only age, pain at baseline and disability at baseline influenced the pain intensity and disability after four weeks of treatment. The beta coefficient for age was statistically significant, but the magnitude of this association was very small and not clinically important.  相似文献   
139.
140.

Purpose

Frail patients are known to experience poor outcomes. Nevertheless, we know less about how frailty manifests itself in patients’ physiology during critical illness and how it affects resource use in intensive care units (ICU). We aimed to assess the association of frailty with short-term outcomes and organ support used by critically ill patients.

Methods

Retrospective analysis of prospective collected data from 93 ICUs in Brazil from 2014 to 2015. We assessed frailty using the modified frailty index (MFI). The primary outcome was in-hospital mortality. Secondary outcomes were discharge home without need for nursing care, ICU and hospital length of stay (LOS), and utilization of ICU organ support and transfusion. We used mixed logistic regression and competing risk models accounting for relevant confounders in outcome analyses.

Results

The analysis consisted of 129,680 eligible patients. There were 40,779 (31.4%) non-frail (MFI?=?0), 64,407 (49.7%) pre-frail (MFI?=?1–2) and 24,494 (18.9%) frail (MFI?≥?3) patients. After adjusted analysis, frailty was associated with higher in-hospital mortality (OR 2.42, 95% CI 1.89–3.08), particularly in patients admitted with lower SOFA scores. Frail patients were less likely to be discharged home (OR 0.36, 95% CI 0.54–0.79) and had higher hospital and ICU LOS than non-frail patients. Use of all forms of organ support (mechanical ventilation, non-invasive ventilation, vasopressors, dialysis and transfusions) were more common in frail patients and increased as MFI increased.

Conclusions

Frailty, as assessed by MFI, was associated with several patient-centered endpoints including not only survival, but also ICU LOS and organ support.
  相似文献   
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