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991.
Kim SW Yoo SH Lee HJ Kim K Kim do R Park SK Chang MS 《Bulletin of environmental contamination and toxicology》2012,88(1):112-117
We investigated the effects of Cistanches herba (CH) on the male reproductive system in mice, assessing CREM gene expression and spermatogenesis. Our results demonstrate
that CH treatment lead to a significant decrease in sperm count dose-dependently, 298.3 ± 48.9 vs. 296.6 ± 102.4 (250 mg/kg),
236.7 ± 75.1 (500 mg/kg), 223.0 ± 48.7 × 106 (1000 mg/kg), respectively. Additionally, serum testosterone levels decreased following CH treatment to as low as ~57% compared
with the vehicle-treated group. CREM gene expression was also down-regulated following CH treatment and histological examination
of the testicular seminiferous tubules showed severe damage on CH treatment. These results suggest that CH induces cytotoxicity
in the male reproductive system, through the inhibition of spermatogenesis, testicular damage, and limited hormonal function. 相似文献
992.
Turner JW Robinson JD Alaoui A Winchester J Neustadtl A Levine BA Collmann J Mun SK 《Health care management review》2003,28(2):95-106
Media attitudes and media use have been the focus of considerable academic research. This article uses this research to explore patient and health care practitioner attitudes toward telemedicine interactions via videoconferencing technology. 相似文献
993.
Rosidah Mun Fei Yam Amirin Sadikun Mariam Ahmad Gabriel Akyirem Akowuah Mohd. Zaini Asmawi 《Journal of ethnopharmacology》2009
Aims of the study
Gynura procumbens (Merr.), which is known as “Sambung nyawa”, is widely used in South East Asian countries in the traditional treatment of many ailments. However, there is little toxicological information available regarding safety following repeated exposure.The present investigation describes the toxicity of a methanol extract of Gynura procumbens leaves in rats.Materials and methods
For acute toxicity studies, a methanol extract of Gynura procumbens was orally administered to Sprague–Dawley rats (female and male) at a dose range of 1000–5000 mg/kg. For sub-chronic toxicity studies, the rats were orally administered the methanol extract of Gynura procumbens at the doses of 125, 250, and 500 mg/(kg day) for a period of 13 weeks. The animals were sacrificed, followed by examination of their organs and blood serum.Results and conclusions
Administration of the methanol extract from Gynura procumbens leaves at 1000–5000 mg/kg did not produce mortality or significant changes in the general behaviour, body weight, or organ gross appearance of rats. There were no significant differences in the general condition, growth, organ weights, haematological parameters, clinical chemistry values, or gross and microscopic appearance of the organs from the treatment groups as compared to the control group. Therefore, the NOAEL for the Gynura procumbens methanol extract is 500 mg/(kg day) administered orally for 13 weeks. 相似文献994.
A qualitative study was conducted to examine parental concerns over the issue of disclosure with those whose children were diagnosed with HIV/AIDS. Semi-structured interviews were conducted with seven parents and the main issues that arose from the interviews were (a) parents' explanation of their children's medical condition; (b) factors that influence disclosure; (c) factors that hinder disclosure; and (d) parents' perception on the appropriate time for disclosure. Parents viewed disclosure as a single event, as opposed to an ongoing process where varying levels of information on the illness was to be provided in accordance to the children's individual cognitive and emotional development. 相似文献
995.
Two cases of natural killer (NK)/T-cell primary nasal lymphoma with similar clinical presentations are reported, for comparison and contrast, to highlight the clinical issues and challenges posed by this unusual disease, its aggressiveness being matched only by its rarity. Presenting as a lesion in the nasal cavity with histological features of malignant lymphoma, primary nasal lymphoma is an uncommon extranodal lymphoma, which poses problems in both diagnosis and management. In people of oriental descent, the common cell subtype is NK/T-cell. Although it is generally thought that combination treatment with chemotherapy and radiation is the best management for early stage non-Hodgkin's lymphoma (NHL), there is still debate as to whether combined therapy is optimal treatment for this particular subtype of NHL, given that it responds less well to conventional chemotherapy. Herein we report two patients to illustrate these controversies. 相似文献
996.
997.
998.
Metastatic lymph node status in the central compartment of papillary thyroid carcinoma: A prognostic factor of locoregional recurrence 下载免费PDF全文
999.
Specific Inhibition of Phosphodiesterase-4B Results in Anxiolysis and Facilitates
Memory Acquisition
Alexander McGirr Tatiana V Lipina Ho-Suk Mun John Georgiou Ahmed H Al-Amri Enoch Ng Dongxu Zhai Christina Elliott Ryan T Cameron Jonathan GL Mullins Fang Liu George S Baillie Steven J Clapcote John C Roder 《Neuropsychopharmacology》2016,41(4):1080-1092
Cognitive dysfunction is a core feature of dementia and a prominent feature in
psychiatric disease. As non-redundant regulators of intracellular cAMP gradients,
phosphodiesterases (PDE) mediate fundamental aspects of brain function relevant to
learning, memory, and higher cognitive functions. Phosphodiesterase-4B (PDE4B) is an
important phosphodiesterase in the hippocampal formation, is a major Disrupted in
Schizophrenia 1 (DISC1) binding partner and is itself a risk gene for psychiatric
illness. To define the effects of specific inhibition of the PDE4B subtype, we
generated mice with a catalytic domain mutant form of PDE4B (Y358C) that has
decreased ability to hydrolyze cAMP. Structural modeling predictions of decreased
function and impaired binding with DISC1 were confirmed in cell assays. Phenotypic
characterization of the PDE4BY358C mice revealed facilitated
phosphorylation of CREB, decreased binding to DISC1, and upregulation of DISC1 and
β-Arrestin in hippocampus and amygdala. In behavioral assays,
PDE4BY358C mice displayed decreased anxiety and increased exploration,
as well as cognitive enhancement across several tests of learning and memory,
consistent with synaptic changes including enhanced long-term potentiation and
impaired depotentiation ex vivo. PDE4BY358C mice also
demonstrated enhanced neurogenesis. Contextual fear memory, though intact at
24 h, was decreased at 7 days in PDE4BY358C mice, an effect
replicated pharmacologically with a non-selective PDE4 inhibitor, implicating cAMP
signaling by PDE4B in a very late phase of consolidation. No effect of the
PDE4BY358C mutation was observed in the prepulse inhibition and forced
swim tests. Our data establish specific inhibition of PDE4B as a promising
therapeutic approach for disorders of cognition and anxiety, and a putative target
for pathological fear memory. 相似文献
1000.
Eun Hwa Park Do Rim Kim Ha Young Kim Seong Kyu Park Mun Seog Chang 《Asian journal of andrology》2014,16(6):845-851
The cation channel of sperm (CatSper) protein family plays important roles in male reproduction and infertility. The four members of this family are expressed exclusively in the testis and are localized differently in sperm. To investigate the effects of Panax ginseng treatment on the expression of CatSper genes and sperm hyperactivation in male mice, sperm motility and CatSper gene expression were assessed using a computer-assisted semen analysis system, a Fluoroskan Ascent microplate fluorometer to assess Ca2* influx, real.time polymerase chain reaction, Western blotting and immunofluorescence. The results suggested that the Ca2* levels of sperm cells treated with P. ginseng were increased significantly compared with the normal group. The P. ginseng-treated groups showed increased sperm motility parameters, such as the curvilinear velocity and amplitude of lateral head displacement. Taken together, the data suggest that CatSper messenger ribonucleic acid levels were increased significantly in mouse testes in the P. ginseng-treated group, as was the protein level, with the exception of CatSper2. In conclusion, P. ginseng plays an important role in improving sperm hyperactivation via CatSper gene expression. 相似文献