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101.
Ginseng, the root of Panax ginseng C. A. Meyer (Araliaceae), is one of the most important traditional medicines and functional foods. A detailed phytochemical investigation on the roots of P. ginseng led to the isolation of 6 new natural protopanaxatriol (PPT)-type ginsenosides, ginsenosides Re(1)-Re(6) (compounds 1-6), along with 10 known PPT-type ginsenosides. Their structures were elucidated on the basis of chemical and spectroscopic analyses, including high-resolution mass spectrometry (HRMS) and 1D and 2D nuclear magnetic resonance (NMR). The unusual α-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl sugar chain, as found in compounds 1 and 2, is reported in the genus Panax for the first time.  相似文献   
102.
云南高原甘薯地方品种征集鉴定研究   总被引:6,自引:0,他引:6  
 自1993年以来,分别深入到云南省的14个地、州、市,45个县、区实地征集甘薯地方品种资源。1995~1996年将收集到的105份地方品种材料进行田间比较鉴定。对地区来源相同,名称相似的品种材料进行分类比较,初步认定。根据植物学形态特征和生理生态特性,对一些同名异种,异名同种的品种材料进行了认真的区分、整理、归并。将全省所征集到的105份甘薯地方品种材料归并为40份。并经生产力鉴定,筛选出“瑞丽紫红皮”、“普洱黄山芋”等一批具有推广潜力的优良地方品种,可在云南省甘薯生产上逐步推广使用。  相似文献   
103.
The performance of a clinical trial for pharmaceutical agents is usually undertaken only after there is likely benefit demonstrated from the use of the putative agent. The consideration of botanical products as pharmaceutical agents must similarly go through a rigorous evaluation process. The present work reviews the recently published phase II study evaluating the effectiveness of black cohosh and red clover in a randomized trial with conjugated equine estradiol/medroxyprogesterone acetate and placebo for the treatment of menopausal symptoms. We analyze the possible reasons why this study failed to show benefit for either botanical product in reducing menopause-related vasomotor symptoms.  相似文献   
104.
105.
广东省野生稻种质资源对褐稻虱的抗性鉴定   总被引:2,自引:1,他引:2  
利用野生稻抗逆性强,适应性广,一些系统兼抗多种水稻病虫等特异性状,培育产量高、抗性好的品种,愈来愈受到人们的重视。本院野生稻研究组在全省范围内收集了一批野生稻种质资源,作者于1981—1986年对这批资源进行了抗褐稻虱试验,以便从中找出抗褐稻虱的抗性材料.用于水稻的抗虫育种。  相似文献   
106.
CASE HISTORY: A 6-year-old, neutered, female Angora cat presented with a history of lethargy and anorexia for 2 months and a clinically palpable and gradually enlarging, solid mass in the abdominal cavity extending from the last costal arch to the pelvic cavity.

CLINICAL FINDINGS: Examination of the cat revealed jaundice, dehydration and hypothermia. Haematological manifestations included lymphopenia and substantial decrease in haematocrit value. Biochemical analysis of the blood revealed hypoglycaemia, three-fold elevated blood urea nitrogen values, increased level of serum aspartate aminotransferase and increased total bilirubin while the creatinine level was normal. Ultrasonographic examination of the abdomen showed a disrupted and large hypoechoic area around the left kidney. The cat was anaesthetised and the left kidney was removed, but the cat died following surgery.

PATHOLOGICAL FINDINGS: On post-mortem examination, the left kidney was markedly enlarged and both the cortical and medullary parenchyma were replaced by confluent, multilobulated, pale tan-white, firm nodular masses protruding above the capsular surface. Metastasis was not observed. Cytological examination revealed a population of spindle-shaped cells of variable size, with abundant coarse chromatin and occasionally prominent nucleoli. Initial sections of the kidney were indicative of undifferentiated sarcoma confirmed by immunohistochemistry revealing vimentin-positive and cytokeratin-negative results in all tumour tissues. Additional sections showed very small amounts of both cytokeratin-positive and vimentin-positive areas.

DIAGNOSIS: Sarcomatoid renal cell carcinoma (SRCC) with scant epithelial components originating from left kidney.

CLINICAL RELEVANCE: Clinical and pathological features were similar to those of human SRCC, even though there was no evidence of metastases. Immunohistochemistry for vimentin and cytokeratin may be useful for definitive diagnosis of renal cell carcinoma with sarcomatoid differentiation, although staining of sections from several different parts of the tumour may be necessary. When a primary renal tumour is presented, SRCC should be considered as this diagnosis may influence treatment protocols and the clinical outcome.  相似文献   
107.
米老排造林密度试验初报   总被引:2,自引:3,他引:2       下载免费PDF全文
米老排(Mytilaria laosensis)属金缕梅科半落叶乔木,是中国南亚热带优良速生用材树种,材质优良,经济效益高。60年代在广西大青山试种成功后,已成为主要的造林树种之一。广西已发展到1300ha,幼林普遍生长良好,但某些林分因密度过大而出现生势衰退现象。如何提高经营水平,合理确定其造林密度,是有待解决的问题。为此,1980年我们做了米老排造林密度试验,取得了初步成效。现将试验结果初报如下。  相似文献   
108.
Eight botanical preparations that are commonly used for the treatment of menopausal symptoms were tested for estrogenic activity. Methanol extracts of red clover (Trifolium pratense L.), chasteberry (Vitex agnus-castus L.), and hops (Humulus lupulus L.) showed significant competitive binding to estrogen receptors alpha (ER alpha) and beta (ER beta). With cultured Ishikawa (endometrial) cells, red clover and hops exhibited estrogenic activity as indicated by induction of alkaline phosphatase (AP) activity and up-regulation of progesterone receptor (PR) mRNA. Chasteberry also stimulated PR expression, but no induction of AP activity was observed. In S30 breast cancer cells, pS2 (presenelin-2), another estrogen-inducible gene, was up-regulated in the presence of red clover, hops, and chasteberry. Interestingly, extracts of Asian ginseng (Panax ginseng C.A. Meyer) and North American ginseng (Panax quinquefolius L.) induced pS2 mRNA expression in S30 cells, but no significant ER binding affinity, AP induction, or PR expression was noted in Ishikawa cells. Dong quai [Angelica sinensis (Oliv.) Diels] and licorice (Glycyrrhiza glabra L.) showed only weak ER binding and PR and pS2 mRNA induction. Black cohosh [Cimicifuga racemosa (L.) Nutt.] showed no activity in any of the above in vitro assays. Bioassay-guided isolation utilizing ER competitive binding as a monitor and screening using ultrafiltration LC-MS revealed that genistein was the most active component of red clover. Consistent with this observation, genistein was found to be the most effective of four red clover isoflavones tested in the above in vitro assays. Therefore, estrogenic components of plant extracts can be identified using assays for estrogenic activity along with screening and identification of the active components using ultrafiltration LC-MS. These data suggest a potential use for some dietary supplements, ingested by human beings, in the treatment of menopausal symptoms.  相似文献   
109.
Reactive dye is a popular dye for dyeing cotton fiber due to its very good color fastness which is explained by the formation of covalent bond between dye and fiber. In this study, practicality of reuse of reactive dye by compensating for the hydrolyzed part of the dye solution is examined. A monofunctional dye (vinyl sulfone type) was used and it was found that dyeing cotton fiber with reused dyebath is possible. Since bifunctional dye can improve the chance of dye-fiber bond formation, vinyl sulfone based bifunctional reactive dyes were also selected in this study. Three types of bifunctional dyes were used and they basically share the same vinyl sulfone group; other reactive groups are monochlorotriazine, dichlorotriazine and vinyl sulfone. Such dyes were chosen in order to compare their respective efficiencies under the effect of one common reactive group. The aim of this study was to compare the effect of hydrolyzed and unhydrolyzed proportions of mono-and bifunctional reactive dyes on cotton fiber and study the possibility and efficiency of the two different reuse dyebath systems.  相似文献   
110.
The effect on true potato seed (TPS) weight of supplemental nitrogen (N) applied during seed development was investigated using crosses DTO-33 × R128.6 (“A” produced in the field) and Atzimba × R128.6 (“B” produced in the field and in a screenhouse). Dry weights of tops and tubers of the mother plants were also measured in the screenhouse. The response to supplemental N (0-240 kg/ha) in 100-TPS weight of cross A and B from the field was positive and linear. In the screenhouse, where higher total N (0-1200 kg/ha) was applied, the responses in 100-TPS weight and dry weight of tops and tubers were curvilinear, with maximum levels at 800, 1000 and 400 kg/ha, respectively. The 100-TPS weight of cross B was 40% higher in the field than in the screenhouse. In the field, increased frequency of supplemental N applications increased 100-TPS weight of large and medium berries of cross B, but had no effect on seed from small berries nor on seed from any berries of cross A. In the screenhouse, increased application frequency decreased tuber dry weight and increased dry weight of tops, but had no effect on 100-TPS weight. It was concluded that supplemental N must be applied during seed development and at higher total levels than those required for optimum tuber yields in order to maximize 100-TPS weight. The lower seed weight from the screenhouse suggests that other environmental factors (e.g., temperature) present during growth of the mother plant can affect the weight of the resultant TPS.  相似文献   
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