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161.
After the commercial cultivation of Ganoderma lucidum, that is becoming increasingly popular because of its valuable medicinal effects, a large amount of Ganoderma spent substrate (GSS) remains as a residual material. It is important to identify differences in the chemical compositions among GSS to indicate their suitability. This study was carried out to characterize and evaluate the substrates and GSS for the some chemical contents such as; pH, EC, organic carbon (C), total nitrogen (N), macro and micro elements and C:N ratios. The substrates were prepared by the mixtures of hornbeam and oak sawdust supplemented with wheat bran in a ratio of 20% (20WB) and tea manufacture waste in different ratios (10, 15, 20 and 25%). Organic C, C:N and pH values decreased in GSS, while N, P, K, Mg, Fe, Mn and Zn contents increased. EC and pH values of GSS varied between 1.13 and 2.33 dS m−1, and 5.14 and 5.69, respectively. GSS was found rich in all investigated mineral nutrients. The highest increases in all nutrient contents were generally determined in hornbeam sawdust with 20TW spent substrate. Initial mineral composition of the wastes influenced the mineral composition of the substrates and spent substrates.  相似文献   
162.

Aims

The purpose of this study was to compare the changes of antihyperalgesic effectiveness of zonisamide (25 and 50 mg/kg), an antiepileptic drug, on the early and late phases of neuropathy and to investigate the role of serotonergic descending inhibitory pain pathways in antihyperalgesic effectiveness of zonisamide in the streptozotocin-induced rat model for painful diabetic neuropathy.

Main methods

The hot-plate and tail-immersion, to determine thermal thresholds, and paw pressure withdrawal tests, to determine mechanical thresholds, were performed as hyperalgesia tests. To investigate the role of serotonergic pathway, 1 mg/kg ketanserin (5-HT2A/2C antagonist) and ondansetron (serotonin 5-HT3 receptor antagonist) were used.

Key findings

Zonisamide enhanced pain thresholds significantly in the 3rd, 6th and 8th weeks as the reference drugs morphine (5 mg/kg) and carbamazepine (32 mg/kg, tested only in the 3rd week). There were no observed differences on the potency of antihyperalgesic effect between weeks and between doses. Each antagonist reversed the effect of zonisamide in the hot-plate and tail-immersion tests significantly, but, relatively in the paw pressure withdrawal tests.

Significance

These results support the role for zonisamide in the management of diabetic neuropathic pain in all phases. Serotonin 5-HT2A/2C and 5-HT3 receptors are involved in the antihyperalgesic effect of zonisamide by enhancement of thermal threshold, and partially by mechanical threshold, so they may not mediate mechanical hyperalgesia in diabetic neuropathy.  相似文献   
163.
Penicillin G acylase is the key enzyme used in the industrial production of β-lactam antibiotics. This enzyme hydrolyzes penicillin G and related β-lactam antibiotics releasing 6-aminopenicillanic acid, which is an intermediate in the production of semisynthetic penicillins. To improve the enzymatic activity of Escherichia coli penicillin acylase, sequential rounds of error-prone polymerase chain reaction were applied to the E. coli pac gene. After the second round of evolution, the best mutant M2234 with enhanced activity was selected and analyzed. DNA sequence analyses of M2234 revealed that one amino acid residue (K297I), located far from the center of the catalytic pocket, was changed. This mutant (M2234) has a specific activity 4.0 times higher than the parent enzyme and also displayed higher stability at pH 10.  相似文献   
164.
Archaeobotanical samples from the Middle Bronze Age (MBA; c. 2000–1700 b.c.) city of Kanesh, excavated at the site of Kültepe in Kayseri Province, Turkey, preserve the charred shells of hazelnut (Corylus sp.). Hazelnut species do not naturally grow in the Kayseri area, being a native element of the broadleaf woodlands of Turkey’s Black Sea region, today home to a multi-million dollar international hazelnut export industry. The finds come from both the upper and lower city, being restricted to the Middle Bronze Age Karum level II, an occupation phase which saw the greatest development of the Assyrian trade network of which Kanesh was the administrative centre. This archaeobotanical discovery at Kültepe provides the earliest direct evidence for trade in hazelnuts in the region, probably imported on a small scale as luxury items facilitated by the Assyrian trade network. It also provides independent support for historical claims that hazelnut was traded at Kanesh based on the analysis of cuneiform tablets.  相似文献   
165.
Caulerpa taxifolia is one of the most important and best-studied alien species in the Mediterranean Sea. The present study reveals the macrobenthic assemblages associated with C. taxifolia from the region. We found 26 species from Polychaeta, 31 species from Crustacea, 22 species from Mollusca and 5 species from Echinodermata. In conclusion, C. taxifolia in İskenderun Bay can be considered an ecosystem engineer that modifies local habitats and also enhances biodiversity.  相似文献   
166.
Nontyphoid salmonella (NTS) serotypes can cause gastroenteritis, bacteriemia, and focal infections. However, these focal infections, including urinary tract infections (UTI), are occasionally observed; in particular, the presence of several predisposing factors, such as immunodeficiency and structural abnormality in the urinary tract, increase the possibility of the occurrence of infection. We present a case of UTI caused by Salmonella enterica serovar Virchow in an elderly and debilitated patient with benign prostatic hyperplasia (BPH). Administration of appropriate antibiotic treatment resulted in recovery of the patient's clinical course.  相似文献   
167.
Excision Repair Cross-Complementing Group 1 (ERCC1) is an important DNA repair gene, playing critical role in nucleotide excision repair pathway and having a significant influence on genomic instability. Some studies support that ERCC1 might be a potential predictive and prognostic marker in non-small cell lung cancer (NSCLC). ERCC1 has also been shown to be a promising biomarker in NSCLC treated with a cisplatin-based regimen. Therefore, the determination of ERCC1 expression at DNA, mRNA and protein level in different stages of NSCLC is still an important topic in the cancer. Ninety-one formalin-fixed paraffin-embedded tumor samples histopathologically diagnosed as NSCLC were examined in this study. ERCC1 expression at protein level were scored by immunohistochemistry. The gene amplification and mRNA expression levels for ERCC1 were determined by real-time quantitative PCR. There was complete concordance among the three methods in 39 tumor samples (42.9%). A strong correlation was found between DNA amplification and mRNA expression (r = 0.662) while there was no correlation between mRNA and protein assessment for ERCC1 expression (r = −0.013). ERCC1 expression at mRNA and DNA level (63.1 and 84.2%, respectively) in tumors at stage III was higher than at the other stages. In contrast, the protein expression at stage II and III (56.6 and 52.6%, respectively) of NSCLC was lower than that of tumors with stage I NSCLC. These results show that the mechanism by which ERCC1 expression might play a role in tumor behavior. This study was also confirmed that the appropriate validation and qualification in methods used for ERCC1 status were needed before its clinical application and implementation.  相似文献   
168.
169.
Gibberellic acid improves water deficit tolerance in maize plants   总被引:1,自引:0,他引:1  
The combination effects of water stress and gibberellic acid (GA3) on physiological attributes and nutritional status of maize (Zea mays L. cv., DK 647 F1) were studied in a pot experiment. Maize plants were grown in the control (well watered WW) and water stress subjected to treated both water stress and two concentrations of gibberellic acid (GA3 25 mg L−1, 50 mg L−1). WS was imposed by maintaining the moisture level equivalent to 50 % pot capacity whereas the WW pots were maintained at full pot capacity. Water stress reduced the total dry weight, chlorophyll concentration, and leaf relative water content (RWC), but it increased proline accumulation and electrolyte leakage in maize plants and appears to affect shoots more than roots. Both concentrations of GA3 (25 and 50 mg L−1) largely enhanced the above physiological parameters to levels similar to control. WS reduced leaf Ca2+ and K+ concentrations, but exogenous application of GA3 increased those nutrient levels similar or close to control. Exogenous application of GA3 improved the water stress tolerance in maize plants by maintaining membrane permeability, enhancing chlorophyll concentration, leaf relative water content (LRWC) and some macro-nutrient concentrations in leaves.  相似文献   
170.
Developmental origin of smooth muscle cells in the descending aorta in mice   总被引:1,自引:0,他引:1  
Aortic smooth muscle cells (SMCs) have been proposed to derive from lateral plate mesoderm. It has further been suggested that induction of SMC differentiation is confined to the ventral side of the aorta, and that SMCs later migrate to the dorsal side. In this study, we investigate the origin of SMCs in the descending aorta using recombination-based lineage tracing in mice. Hoxb6-cre transgenic mice were crossed with Rosa 26 reporter mice to track cells of lateral plate mesoderm origin. The contribution of lateral plate mesoderm to SMCs in the descending aorta was determined at different stages of development. SMC differentiation was induced in lateral plate mesoderm-derived cells on the ventral side of the aorta at embryonic day (E) 9.0-9.5, as indicated by expression of the SMC-specific reporter gene SM22alpha-lacZ. There was, however, no migration of SMCs from the ventral to the dorsal side of the vessel. Moreover, the lateral plate mesoderm-derived cells in the ventral wall of the aorta were replaced by somite-derived cells at E10.5, as indicated by reporter gene expression in Meox1-cre/Rosa 26 double transgenic mice. Examination of reporter gene expression in adult aortas from Hoxb6-cre/Rosa 26 and Meox1-cre/Rosa 26 double transgenic mice suggested that all SMCs in the adult descending aorta derive from the somites, whereas no contribution was recorded from lateral plate mesoderm.  相似文献   
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