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1.
The destructive resolution of (6aR,S)-glaucine (Ic) was accomplished by oxidation of the (6aS)-(+)-enantiomer (Ia), using Fusarium solani ATCC 12823 to yield the unnatural alkaloid (6aR)-(-)-glaucine (Ib). Eighteen cultures were examined for their ability to metabolize the (6aR)-(-)-enantiomer (Ib), and Aspergillus flavipes ATCC 1030 was found to catalyze the stereoselective oxidation of this substrate to didehydroglaucine. Thus, it has been demonstrated that "R" and "S" organisms exist with regard to the oxidation of aporphines to didehydroaporphines.  相似文献   
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This laboratory study measured growth of one plant species, Lycopersicon esculentum Big Girl (tomato), that is sensitive to the presence of soil contamination, in Kuwait soil amended with crude-oil-contaminated soil. Germinated tomato seeds were placed in containers with soil containing 0, 0.12, 0.24, 0.36, 0.48, 0.60, 1.2, and 2.4% crude oil and were grown in an indoor growth chamber. Plants grew in Kuwait soil containing up to 0.36% crude oil; however, growth and fruit production were compromised at crude oil concentrations greater than 0.12% when compared with control plants. Plants did not grow in Kuwait soil amended with 0.48% crude oil or higher.  相似文献   
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BackgroundThe disease course of human immunodeficiency virus (HIV) is often altered by existing or newly acquired coincident infections.Conclusions/SignificanceWe were unable to find a significant effect of W. bancrofti infection or its treatment on HIV clinical course or surrogate markers of HIV disease progression though we recognized that our study was limited by the smaller than predicted sample size and by the use of ART in half of the patients. Treatment of W. bancrofti coinfection in HIV positive subjects (as is usual in mass drug administration campaigns) did not represent an increased risk to the subjects, and should therefore be considered for PLWHA living in W. bancrofti endemic areas.

Trial Registration

ClinicalTrials.gov NCT00344279  相似文献   
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Ginkgo biloba extract has been therapeutically used for several decades to increase peripheral and cerebral blood flow as well as for the treatment of dementia. The extract contains multiple compounds such as flavonoids and terpenoids that are thought to contribute to its neuroprotective and vasotropic effects. In this study, we investigated the effect of prolonged administration of EGb 761, up to 10 weeks, on mammalian retina using Fourier transform infrared spectroscopy (FTIR). Two main groups were involved in this study: the normal group (n = 10); and EGb-administrated group (n = 50) that received—orally—a dose of 40 mg/kg/day EGb 761. The results demonstrated that EGb administration was associated with different beneficial effects on the retinal constituents especially the underlying amide I protein secondary structure components as well as the NH-OH region. It concluded that the optimum daily administration period of EGb (40 mg/kg) for ophthalmic applications that targeting the retina ranges from 5 to 8 weeks.  相似文献   
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OBJECTIVE: To retrospectively evaluate cellularity and correlate the presence of columnar cells with specimen interpretation in conventionally prepared anal cytologic smears from an HIV-positive population. STUDY DESIGN: Two cytopathologists and 1 senior cytotechnologist, blinded to the original diagnosis, screened 114 samples from 110 patients collected between 1997 and 2002. One hundred nine males and 1 female were included, age ranging from 23 to 52 years. Discrepancies were reviewed for consensus. The interpretations, cellularity, and presence or absence of columnar cells were noted. The relationships between diagnosis and presence of columnar cells, visible anal lesions, concurrent HIV viral load and CD4+ T-cell counts were assessed. RESULTS: The cytologic findings were as follows: 7, unsatisfactory (6%); 29, negative (25%); 25, atypical squamous cells of undetermined significance (22%); and 53, dysplasia (47%) (42 anal intraepithelial lesion 1 [37%] and 11 anal intraepithelial lesion 2/3 [10%]). Nearly 50% of the smears, 51, showed the presence of columnar cells (45%); 37 of those specimens had some degree of dysplasia (74%). Of the 63 specimens with no columnar cells, 16 (25%) showed dysplasia. Columnar cells were absent from all unsatisfactory specimens. CONCLUSION: A highly significant association between the presence of columnar cells and anal intraepithelial lesion (p<0.001) and a significant association between the presence of columnar cells and atypical cytology when a visible lesion was absent (p=0.0019) were found. No significant relationship was found between the presence/degree of dysplasia and CD4+ T-cell counts or HIV viral load. Lack of clinical follow-up precluded evaluation of the false negative rates in this data set.  相似文献   
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For decades, mesenchymal stem (MSCs) cells have been used for cardiovascular diseases as regenerative therapy. This review is an attempt to summarize the types of MSCs involved in myocardial infarction (MI) therapy, as well as its possible mechanisms effects, especially the paracrine one in MI focusing on the studies (human and animal) conducted within the last 10 years. Recently, reports showed that MSC therapy could have infarct‐limiting effects after MI in both experimental and clinical trials. In this context, various types of MSCs can help cardiac regeneration by either revitalizing the cardiac stem cells or revascularizing the arteries and veins of the heart. Furthermore, MSCs could produce paracrine growth factors that increase the survival of nearby cardiomyocytes, as well as increase angiogenesis through recruitment of stem cell from bone marrow or inducing vessel growth from existing capillaries. Recent research suggests that the paracrine effects of MSCs could be mediated by extracellular vesicles including exosomes. Exosomal microRNAs (miRNAs) released by MSCs are promising therapeutic hotspot target for MI. This could be attributed to the role of miRNA in cardiac biology, including cardiac regeneration, stem cell differentiation, apoptosis, neovascularization, cardiac contractility and cardiac remodeling. Furthermore, gene‐modified MSCs could be a recent promising therapy for MI to enhance the paracrine effects of MSCs, including better homing and effective cell targeted tissue regeneration. Although MSC therapy has achieved considerable attention and progress, there are critical challenges that remains to be overcome to achieve the most effective successful cell‐based therapy in MI.  相似文献   
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Ghrelin hormone has an important role in a wide range of metabolic and non-metabolic processes. Polymorphisms of ghrelin gene could be associated with a large number of diseases. The aim of this study was to evaluate the association of ?604G/A and ?501A/C polymorphisms in ghrelin and obestatin prepropeptide gene (GHRL) with polycystic ovary syndrome (PCOS) in a sample of Iranian women. One hundred and fifty-two women with PCOS and 162 age-matched apparently healthy women as control group were enrolled in this study. The study subjects were genotyped for polymorphisms in the ghrelin gene using polymerase chain reaction–restriction fragment length polymorphism-based methods. Biochemical parameters, serum prolactin, luteinizing hormone, follicle stimulating hormone, estradiol, and testosterone were estimated by chemiluminescence assay. Serum lipids and lipoproteins were determined by standard enzymatic methods. The association between the risk of PCOS and ghrelin gene polymorphisms was examined using Multivariate analysis. The frequency of the ?604G/A and ?501A/C polymorphisms was not statistically different between patients and the control group of women (p = 0.12 and p = 0.21, respectively). A significantly higher level of LDL-C was found in the wild-type AA genotype compared with CC genotype of ?501A/C polymorphism (p = 0.02). Our findings indicate that neither ?604G/A and nor ?501A/C polymorphisms of ghrelin gene are associated with PCOS, but suggest a relation between the presence of polymorphic allele of ?501A/C polymorphism and LDL-C level in a sample of Iranian women.  相似文献   
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