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961.
骨缘当归的化学成分   总被引:2,自引:0,他引:2  
骨缘当归Angellica cartilaginomarginata var.foliata Yuan et Shen,别名:山藁本、野芹菜(江苏),仅分布于江苏和浙江。在江苏镇江等地用干燥全草作山藁本入药,其化学成分未见报道。 样品采自江苏省句容县。将干根磨粉,提取物经中性氧化铝层析,根据色谱及光谱鉴定为两种脂肪酸、四种已知香豆素和一种植物甾醇即:正葵酸(n-capric acid)、月桂酸(lauric acid)、骨缘当归素(cartilaginomarginadin)、蝉翼素(pteryxin)、白花前胡素F(praeruptorin F)、佛手柑内酯(bergapten)及β-谷甾醇(β-sitosterol)。  相似文献   
962.
本文用免疫组织化学方法,分别在冰冻和石蜡切片上,对24例不同胎龄的胎儿肝比较研究了肝内 AFP~+细胞数量及其与 T,B 淋巴细胞之间的关系。结果发现 AFP 仅分布于肝细胞内,其他细胞阴性。不同胎龄的肝脏,AFP 的染色强度和阳性率不同。17周前的胎肝,AFP~+细胞最多以后逐渐减少。出生前的肝脏内只有少数 AFP~+细胞。AFP~+细胞的多少与 B 细胞分化发育无多大关系,但与 T 细胞似乎关系密切,两者呈负相关,即 AFP~+细胞多时,T 细胞很少,AFP~+减少时,T 细胞增加,提示 AFP 对 T 细胞具有抑制作用。同时也证明 B 细胞在胎肝内受 T 细胞的影响不大,主要依赖于肝脏的微环境。另外对 AFP 的生物学意义也进行了讨论。  相似文献   
963.
药用寄生植物菟丝子属,列当属和无根藤属氨基酸的分析   总被引:1,自引:0,他引:1  
本文测定了菟丝子属、列当属和无根藤属某些种的种子和植株氨基酸的种类组成和含量。结果表明,3个属种子和植株氨基酸均在15种以上,且含量丰富,特别是必需氨基酸的含量较高。文中讨论了氨基酸的药用和在种子鉴定与化学分类上的作用,探讨了开发应用的前景。  相似文献   
964.
本文用ABC—GDN免疫组织化学方法,研究了γ-氨基丁酸(Gamma—Aminobutyric Acid,GABA)在大鼠胰腺的定位和分布,并用相邻切片法,观察它与胰岛素的共存关系。结果发现GABA免疫反应阳性细胞主要分布于胰腺内分泌部(胰岛)。在外分泌部亦有少许分布。大部分胰岛细胞呈GABA免疫反应阳性,集中位于胰岛的中央部。相邻连续切片免疫染色证实GABA与胰岛素共存于胰岛B细胞中。外分泌部胰腺GABA免疫反应阳性细胞,呈零散分布于腺泡和导管上皮间。本文为进一步探讨GABA在胰腺的生理作用提供了形态学依据。  相似文献   
965.
Using cytochemical method,microspectrophotometry and image analysis,effects of va-soactive intestinal peptide(VIP)on activities of succinic dehydrogenase(SDH)and alkalinephosphatase(ALP)in rat hepatoma cells were studied in vitro.The results showed that thehepatoma cell expressed potent positive reactions of SDH and ALP,the positive positionswere located at the cell membranes and/or cytoplasm.Having been treated with VIP,ALPdecreased obviously in activity(P<0. 01,compared with hepatoma cells untreated by VIP).The sites of ALP activty were chiefly located at the cell membranes,particularly at the cell-cell contacts.Cultured rat hepatoma cells had intensive SDH activity in their cytoplasm.Compared with untreated eclls,there was no marked difference in the intensity of SDH activ-ity in VIP-treated hepatoma cells(P>0.05).  相似文献   
966.
 本文引用Harper(1977)的构件结构理论,从构件结构单位、无性系分株和无性系三个层次,对四川南充市郊慈竹无性系种群的能值特点及其影响能值的计测因素进行了定量研究。研究结果表明:慈竹无性系种群中,各构件单位的去灰分热值(AFCV)分别为:根15349.42J/g、根茎16372.92J/g、秆17106.06J/g、枝18111.99J/g和叶19451.90J/g;慈竹无性系分株的AFCV(J/g)随龄级增大而递增;慈竹无性系水平上的AFCV为:Ⅰ龄占16.47%、Ⅱ龄占25.76%、Ⅲ龄占36.32%、Ⅳ龄为13.08%及Ⅴ龄为8.37%。用恒容燃烧法测定热值时,其能值变化与氧分压密切相关。用经验公式计算的能值较作图法高;用AFCV表示能值较总干重热值(GCV)准确。  相似文献   
967.
25000年以来渤海湾西岸古环境探讨   总被引:5,自引:0,他引:5       下载免费PDF全文
 本文依据孢粉、微体古生物、放射性碳测年、因子分析等资料,表明25000a,BP 以来渤海湾西岸的古植被,古地理环境演变既受气候冷暖变化的影响,又受海平面变化的制约。25000—23000a,BP 为高海平面时期,古植被为森林草甸植被,23000—12000a,BP,气候冷干,为低海平面时期,以草原植被为主,前期和后期为沼泽草甸植被。12000—5000a,BP 气候温凉或温暖湿润为海平面上升时期,为阔叶林草甸或沼泽草甸植被,5000a,BP 以来,气候变凉变干,为海退时期,古植被由沼泽草甸演变为盐生草甸。  相似文献   
968.
Now is the time to refocus efforts in urban research and design. A changing climate and extreme weather events are presenting unique challenges to urban systems around the world. These challenges illuminate the social barriers that accompany disruptive events such as resource inequities and injustices. In this perspective, we provide three research priorities for just and sustainable urban systems that help to address these matters. The three research priorities are: (1) social equity and justice, (2) circularity, and (3) digital twins. Conceptual context and future research directions are provided for each. For social equity and justice, the future directions are mandatory equity analysis and inclusionary practices, understanding and reconciling historical injustices, and intentional integration with diverse community stakeholders. For circularity applications, they are better metrics for integration, more robust evaluation frameworks, and dynamic modeling at multiple spatial and temporal scales. Future directions for digital twins include developing principles to reduce complexity, integrating model and system components, and reducing barriers to data access. These research priorities are core to meeting several of the United Nations Sustainable Development Goals (i.e., 1—No Poverty, 8—Decent Work and Economic Growth, 10—Reduced Inequalities, and 11—Sustainable Cities and Communities). Useful social and technical matters are discussed throughout, where we highlight the importance of prioritizing localized research efforts, provide guidance for community-engaged research and co-development practices, and explain how these priorities interact to align with the evolving field of industrial ecology.  相似文献   
969.

Background

The treatment of Helicobacter pylori (H. pylori) infection is a challenge for those who cannot use amoxicillin.

Objective

To evaluate the eradication rate and adverse effects of vonoprazan and tetracycline dual therapy as first-line and rescue treatment regimens used in special populations with penicillin allergy or failed in previous amoxicillin-containing therapies.

Design

Patients enrolled were those who were H. pylori-positive with selected conditions: (1) allergic to penicillin, either naïve to treatment or had failed before; or (2) failed in previous amoxicillin-containing therapies. All enrolled patients accepted 14-day vonoprazan and tetracycline dual therapy (VT dual therapy) as follows: vonoprazan (20 mg b.i.d.) and tetracycline (500 mg t.i.d. [body weight < 70 kg] or 500 mg q.i.d. [body weight ≥ 70 kg]). H. pylori status was evaluated by 13C-urease breath test 6 weeks after treatment. All adverse effects were recorded. Some patients underwent bacterial culture and antibiotic susceptibility testing.

Results

A total of 62 patients were enrolled; 18 of them received VT dual therapy as first-line treatment, 44 patients received VT dual therapy as rescue treatment. Overall, 58 of 62 patients achieved successful eradication (93.5%), while all involved (100%,18/18) succeeded in the first-line treatment group and 40 cases (90.9%, 40/44) succeeded in the rescue treatment group. Sixty-one (61/62, 98.4%) patients completed the whole course of treatment. Adverse events occurred in 6 patients (6/62, 9.7%), while one patient quit because of skin rash. All adverse effects were mild and relieved spontaneously after H. pylori treatment. Five patients achieved successful H. pylori culture, and all strains isolated were sensitive to tetracycline.

Conclusions

For the treatment of H. pylori infection in special populations with penicillin allergy or failed in previous amoxicillin-containing therapies, a 14-day vonoprazan and tetracycline dual therapy was effective and safe as first-line and rescue treatment in our study. Further study is warranted to verify its efficacy, especially for those who cannot use amoxicillin.  相似文献   
970.
鼎湖山森林群落演替之研究   总被引:9,自引:1,他引:8  
鼎湖山森林群落在自然状态下遵循一定的客观规律向更优化的气候顶极群落演变。本文分析其1955年至1989年(35年)来的演替结果,总结出鼎湖山森林群落演替的进程和模式,进一步应用植物群落演替系统的线性模型和非线性模型对演替进程进行定量研究,并做出相应的演替进程的数量预测。  相似文献   
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