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71.
The aim of this study was to detect genotypic differences between three populations of healthy volunteers from Northern Spain (204 subjects), Nicaragua (120 subjects), and El Salvador (112 subjects) regarding CYP3A4*1B and CYP3A5*3 polymorphisms. No significant differences were found by comparing allelic frequencies between the two Central American populations. The CYP3A5*3 allele frequency was significantly different (P < 0.01) between Central Americans (76%) and Spaniards (91%). By contrast, CYP3A4*1B allele was more prevalent among Central Americans (12.5%) than among North Spaniards (4%) (P < 0.01). Analysis of CYP3A4-3A5 genotype combinations revealed that individuals carrying CYP3A4*1B/CYP3A5*1 were more represented in Central Americans (16.9%) than in Spaniards (5.4%), suggesting a marked linkage disequilibrium. These data are compatible with a higher CYP3A enzyme activity in Central Americans as opposed to Spaniards and other white groups, which could imply differences in dose requirements for drugs metabolized by CYP3A and should be considered in allele-disease association studies.  相似文献   
72.
73.
The current study focuses on the relationships among a trauma history, a substance use history, chronic homelessness, and the mediating role of recent emotional distress in predicting drug treatment participation among adult homeless people. We explored the predictors of participation in substance abuse treatment because enrolling and retaining clients in substance abuse treatment programs is always a challenge particularly among homeless people. Participants were 853 homeless adults from Los Angeles, California. Using structural equation models, findings indicated that trauma history, substance use history and chronicity of homelessness were associated, and were significant predictors of greater recent emotional distress. The most notable result was that recent emotional distress predicted less participation in current substance abuse treatment (both formal and self-help) whereas a substance use history alone predicted significantly more participation in treatment. Implications concerning treatment engagement and difficulties in obtaining appropriate dual-diagnosis services for homeless mentally distressed individuals are discussed.  相似文献   
74.
The goal of this study is to assess Ziziphus lotus’s potential for producing carboxymethylcellulose adsorption membranes with the ability to adsorb methyl green from wastewaters by the revalorization of its cellulosic fraction. The cellulose from this feedstock was extracted by an alkaline process and TAPPI standard technique T 203 cm-99 and afterwards they were carboxymethylated. The obtained carboxymethylcelluloses were deeply characterized, being observed that the carboxymethylcellulose produced from the alkaline cellulose presented the higher solubility due to its lower crystallinity degree (53.31 vs. 59.4%) and its higher substitution degree (0.85 vs. 0.74). This carboxymethylcellulose was cross-linked with citric acid in an aqueous treatment in order to form an adsorption membrane. The citric acid provided rigidity to the membrane and although it was hydrophilic it was not soluble in water. By evaluating the potential of the produced membrane for the removal of pollutant dyes from wastewater, it was observed that the adsorption membrane prepared from the carboxymethylcellulose’s produced from the Ziziphus lotus was able to remove 99% of the dye, methyl green, present in the wastewater. Thus, this work demonstrates the potential of the Ziziphus lotus for the production of a novel and cost-effective carboxymethylcellulose adsorption membrane with high capacity to treat wastewaters.  相似文献   
75.
The midbrain periaqueductal gray is a key structure for the mediation of an integrated defence behaviour. Although a prominent role for glutamate in PAG mechanisms is supported by both behavioural and morphological studies, whether PAG afferents conveying somatosensory information constitute a source of glutamatergic input to the PAG remains unknown. Here, we have compared the projection pattern of orthogradely-labelled spinoannular fibres with the distribution of glutamate-like immunoreactivity in the PAG at the light microscopic level. Transaxonal labelling was observed throughout the whole rostrocaudal axis of the PAG except for the dorsolateral regions. Cell-processes and terminal-reminiscent puncta were strongly immunoreactive in all PAG regions, including the dorsolateral areas. To ascertain whether glutamate-immunoreactive puncta observed at light microscopy indeed constituted axon terminals of the spinoannular system, glutamate-like immunoreactivity was assessed in orthogradely-labelled synaptic terminals using a post-embedding immunogold procedure for electron microscopy. Quantitative analysis of gold particle densities revealed over twice as strong an immunoreactivity in anatomically-identified spinoannular axon terminals as in dendrites postsynaptic to them, perikarya and inhibitory Gray II synapses, as well as an over 5-fold heavier immunolabelling than in glial profiles. These findings reveal that glutamate is accumulated in synaptic terminals of the spinoannular system, supporting a neurotransmitter role for this acidic amino acid in spinofugal afferents to the PAG.  相似文献   
76.

Context  

Severe sepsis is associated with high mortality and increased costs. The ‘Surviving Sepsis Campaign’ (SSC) protocol was developed as an international initiative to reduce mortality. However, its cost-effectiveness is unknown.  相似文献   
77.
In the present work, mussels (Mytilus edulis) were transplanted into a copper (Cu) gradient in Visnes (Norway) for a period of 3 weeks during November 2003. Sites 1 and 2 showed similar low levels of Cu, site 3 had intermediate Cu levels and site 4 was the most polluted with Cu as confirmed by AAS of digestive gland tissue. Values of lysosomal membrane labilization period were significantly lower at sites 3 and 4 compared to sites 1 and 2. The volume density and size of lysosomes was significantly decreased at site 4. The volume density of neutral lipids was also significantly lower at site 4 compared with the rest of sites. The volume density of lipofuscins showed significantly higher values at sites 2 and 3 compared to the reference site 1. Similar results were obtained regarding bioavailable metal levels measured by autometallography. All together, results are indicative of exocytosis of metal-containing lysosomes and lipofuscins to the digestive tubule lumen in mussels from site 4. In fact, autometallographic metal deposits were detected in digestive tubule lumen, brown cells and stomach in site 4 mussels. In agreement, there was a loss of digestive cells in mussels from site 4 (atrophy of the digestive epithelium) and cell type replacement (diminished volume density of digestive cells and increased volume density of basophilic cells). In conclusion, selected biomarkers indicated that mussels transplanted to sites closest to the Cu mine showed significant differences in metal accumulation pattern and in organization of the digestive gland tissue. Finally, female mussels closest to the Cu mine showed advanced gametogenesis with higher gonad index and vitellogenin-like protein levels than mussels at sites 1 and 2.  相似文献   
78.

Introduction

Pharyngocutaneous fistula is the most frequent complication after total laryngectomy. Its incidence varies between 9%-25% in post primary total laryngectomy patients, to 14%-57% in salvage laryngectomy post radiotherapy or post chemotherapy + radiotherapy. The pectoralis major myofascial flap (PMMF)is postulated as a useful tool to decrease the incidence of this complication.

Materials and method

Retrospective analysis of a group of patients treated by salvage laryngectomy, associated or not with pharyngeal closure reinforcement with PMMF.

Results

Twenty patients were included, 18 males (90%) and 2 females (10%), in 10 of whom the PMMF was used. The average age was 66.65 years. Seventeen (85%) had a laryngeal tumour and 3 (15%) had a hypopharyngeal tumour. Eight (80%) patients in the non-PMMF group had postoperative fistula, whereas only 2 (20%) patients in the PMMF group had a fistula during the postoperative period (P = .005). The mean time for fistula closure was significantly shorter in the cases where PMMF flap was used (16 ± 11 days vs. 76.8 ± 67 days, P = .001), as was hospital stay (19. 6 ± 18 days vs. 83.9 ± 77 days, P = .001).

Conclusion

The use of PMMF in our series is associated with a lower rate of post salvage laryngectomy fistulas in patients treated primarily by organ preservation protocol for laryngeal/hypopharyngeal cancer. In turn, it promotes local healing by decreasing the mean duration of fistula closure and the mean hospital stay.  相似文献   
79.
Limosilactobacillus reuteri INIA P572 is a strain able to produce the antimicrobial compound reuterin in dairy products, exhibiting a protective effect against some food-borne pathogens. In this study, we investigated some probiotic properties of this strain such as resistance to gastrointestinal passage or to colonic conditions, reuterin production in a colonic environment, and immunomodulatory activity, using different in vitro and in vivo models. The results showed a high resistance of this strain to gastrointestinal conditions, as well as capacity to grow and produce reuterin in a human colonic model. Although the in vitro assays using the RAW 264.7 macrophage cell line did not demonstrate direct immunomodulatory properties, the in vivo assays using a Dextran Sulphate Sodium (DSS)-induced colitic mice model showed clear immunomodulatory and protective effects of this strain.  相似文献   
80.
We describe a rare case of metastasis to the paranasal sinuses. The lesion had an immunohistochemical (positivity for cytokeratin 20, negativity for cytokeratin 7, overexpression of p53) and in situ hybridisation profile (neither lesions showed deletion for p53) consistent with metastasis from the earlier rectal adenocarcinoma. The correct typification of intestinal-type neoplasms requires a combination of morphological, immunohistochemical and, sometimes, molecular analysis.  相似文献   
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