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91.
The pathophysiological mechanism behind the link between antipsychotic drugs and sexual dysfunction is still unknown. The goal of this research is to compare the potential effects of antipsychotics on the male reproductive system. Fifty rats were randomly assigned into the five groups indicated: Control, Haloperidol, Risperidone, Quetiapine and Aripiprazole. Sperm parameters were significantly impaired in all antipsychotics-treated groups. Haloperidol and Risperidone significantly decreased the level of testosterone. All antipsychotics had significantly reduced inhibin B level. A significant reduction was observed in SOD activity in all antipsychotics-treated groups. While GSH levels diminished, MDA levels were rising in the Haloperidol and Risperidone groups. Also, the GSH level was significantly elevated in the Quetiapine and Aripiprazole groups. By causing oxidative stress and altering hormone levels, Haloperidol and Risperidone are damaging to male reproductivity. This study represents useful starting point for exploring further aspects of the underlying mechanisms reproductive toxicity of antipsychotics.  相似文献   
92.
The AbA content of cucumber shoot tips was determined by GLC.Shoot tips of monoecious plants had a higher AbA content thanthose of gynoecious ones, and SD conditions caused higher AbAcontent than LD conditions. AbA content per unit dry weightof young floral buds was 5- to 9-fold higher than in older ones. A GLC method was developed to allow parallel identificationand quantitative determinations of GA3 and AbA with the samesample. The shoot tip contents of both growth substances weredetermined at four developmental stages of the monoecious plant.Both significantly increased until the 12th day after plantingthen decreased; the GA3 content decreased markedly. A general hypothesis for the role of growth substances in regulatingsex expression of cucumber is presented and discussed. (Received January 7, 1977; )  相似文献   
93.
Colonies of the fungus Diplodia natalensis produce ample anastomoses which are visible 0.5–1.0 mm inwards of the colony's periphery. Anastomose formation as well as other morphogenetic features, were followed by autoradiography, lectin binding and application of the chitin synthase inhibitor polyoxin D.Hyphal tips and septae were strongly labelled by short pulses of [3H] N-acetyl-D-glucosamine ([3H]GlcNAc) and were showing marked fluorescence after exposure to fluorescein isothiocyanate (FITC) conjugated wheat germ agglutinin (WGA).The dynamics of wall formation was followed by pulse and chase as well as by pulse and wash treatments in which the colony was shortly exposed to [3H]GlcNAc and then freed from the radioactive chitin precursor.Application of the chitin synthase inhibitor polyoxin D caused hyphal tip swellings as well as inflations and balloons along the hyphae at sites of initial new outgrowths and anastomoses. These structures were strongly fluorescenting after FITC-WGA application, indicating imbalance of wall formation and wall lysis.FITC-WGA binding, [3H]GlcNAc labelling and/or exposure to polyoxin D, indicated a process of anastomose formation which starts with short outgrowths of two juxtapositioned hyphae and ends with a complete bridge formation.Abbreviations FITC fluorescein isothiocyanate - WGA wheat germ agglutinin - GlcNAc N-acetyl-D-glucosamine  相似文献   
94.
Summary Our previous studies indicated that fusion products with one functional nucleus but organelles of the two fusion partners (i.e. heteroplastomic cybrids) could be obtained by fusing X-irradiated (cytoplasmic donor) with non-irradiated (recipient) Nicotiana protoplasts. The present report deals with the analysis of mitochondria in cybrid populations resulting from the fusion of donor Nicotiana tabacum protoplasts with recipient protoplasts having a N. Sylvestris nucleus but chloroplasts of an alien Nicotiana species, and exhibiting cytoplasmic male sterility. The two fusion parents showed significant differences in restriction patterns of their chloroplast and mitochondrial DNA. Four groups of cybrid plants were obtained by this fusion. All had N. sylvestris nuclei but contained either donor or recipient chloroplasts and had either sterile or fertile anthers. There was no correlation between anther fertility and chloroplasts type. The mitochondrial DNA restriction patterns of sterile cybrids were similar to the respective patterns of the sterile fusion partner while the mitochondrial DNA restriction patterns of the fertile cybrids were similar to the respective patterns of the fertile fusion partner. The results indicate an independent assortment of chloroplasts and mitochondria from the heteroplastomic fusion products.  相似文献   
95.
The study of epithelial differentiation touches upon many modern aspects of biology. The epithelium is in constant dialogue with the underlying mesenchyme to control stem cell activity, proliferation in transit-amplifying compartments, lineage commitment, terminal differentiation and, ultimately, cell death. There are spatially distinct compartments dedicated to each of these events. Recently we reported that heparanase is expressed in nucleus as well as in the cytoplasm and that nuclear heparanase seems to be related to cell differentiation. In this study, we investigated the role of nuclear heparanase in differentiation by transducing human mammary epithelial cancer cells with heparanase which was delivered specifically into nucleus. We observed that expression of nuclear heparanase allowed the cells to differentiate with the appearance of lipid droplets. This finding supports the idea that heparanase plays a novel role in epithelial cell differentiation apart from its known enzymatic function.  相似文献   
96.
Although automated continuous-monitoring blood culture systems are both rapid and sensitive, false-positive and false-negative results still occur. The objective of this study, then, was to evaluate negative results occurring with BacT/Alert 3D blood culture systems. A total of 1032 samples were cultured with the BacT/Alert 3D automated blood culture system, using both aerobic (FA) and anaerobic (FN) [corrected] media, and 128 of these samples yielded positive results. A total of 904 negative blood samples were then subcultured in 5% sheep blood agar, eosin methylene blue, chocolate agar, and sabouraud-dextrose agar. Organisms growing on these subcultures were subsequently identified using both Vitek32 (bioMerieux, Durham, NC) and conventional methods. Twenty four (2.6%) of the 904 subcultures grew on the subculture media. The majority (83.3%) of these were determined to be gram-positive microorganisms. Fourteen (58.3%) were coagulase-negative staphylococci, two (8.3%) were Bacillus spp., one (4.2%) was Staphylococcus aureus, and one (4.2%) was identified as Enterococcus faecium. Streptococcus pneumoniae and Neisseria spp. were isolated together in two (8.3%) vials. Gram-negative microorganisms comprised 12.5% of the subcultures, of which two (8.3%) were found to be Pseudomonas aeruginosa, and one (4.2%) was Pseudomonas fluorescens. The other isolate (4.2%) was identified as Candida albicans. We conclude that the subculture of negative results is valuable in the BacT/Alert 3D system, especially in situations in which only one set of blood cultures is taken.  相似文献   
97.
Roots and barks of various Berberis species are used as folk remedy for the treatment of various inflammatory diseases such as lumbago, rheumatism and to reduce fever. Six isoquinoline alkaloids namely berberine, berbamine, palmatine, oxyacanthine, magnoflorine, and columbamine were isolated as the main components of alkaloidal fraction from the roots of Turkish Berberis species and effects were studied using various in vivo models in mice. All alkaloids inhibited inflammations in varying degrees, among them berberine, berbamine and palmatine were shown to possess significant and dose-dependent inhibitory activity against serotonin-induced hind paw oedema both on oral and topical applications and acetic acid-induced increase in vascular permeability on oral administration. Moreover, these three alkaloids were also shown to possess dose-dependent antinociceptive activity, which assessed by using the model based on the inhibition of p-benzoquinone-induced writhing movements as well as antipyretic activity on FCA-induced increased rectal temperature on subacute administration. However, all alkaloids induced gastric lesions in varying degrees.  相似文献   
98.
Scanning Electron Microscopy of Intact Trichoderma Colonies   总被引:2,自引:1,他引:1       下载免费PDF全文
Scanning electron microscopy revealed a clear distinction between hyphal types and enabled early detection of hyphal initiation. Stages in the photoinduced differentiation in Trichoderma leading to conidiation could thus be studied.  相似文献   
99.
ABSTRACT

Maternal circadian rhythms provide highly important input into the entrainment and programming of fetal and newborn circadian rhythms. The light-dark cycle is an important regulator of the internal biological clock. Even though pregnant women spend a greater part of the day at home during the latter stages of pregnancy, natural light exposure is crucial for the fetus. The current recommended COVID-19 lockdown might dramatically alter normal environmental lighting conditions of pregnant women, resulting in exposure to extremely low levels of natural daylight and high-intensity artificial light sources during both day and night. This article summarizes the potential effects on pregnant woman and their fetuses due to prolonged exposure to altered photoperiod and as consequence altered circadian system, known as chronodisruption, that may result from the COVID-19 lockdown.  相似文献   
100.
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