广西武鸣县种子植物区系研究

为了解广西武鸣县野生种子植物区系特征, 对其野生种子植物资源进行调查。结果表明,广西武鸣县有野生种子植物2 542种,隶属于184科898属,以被子植物占优势,裸子植物贫乏。从科属组成上看,以大科、单种属和寡种属为主体。科、属和种分布区类型丰富,含典型的热带亚热带成分,兼具温带成分,呈热带至亚热带过渡性质。与邻近地区比较,武鸣县植物多样性比较丰富,植物区系成分与广西横县最相近。因此,武鸣县种子植物多样性丰富、热带性质明显、地理成分多样、起源古老,同时聚集了一些特有植物和珍稀濒危植物,体现出北部湾植物区系的特征。     

广东珠海市种子植物区系研究

调查结果显示,珠海市共有野生维管植物202科718属1448种,其中种子植物166科664属1359种,包括13种国家Ⅱ级保护植物,14种广东省珍稀濒危植物;特有成分贫乏。珠海市种子植物区系以热带亚热带成分占优势,温带成分贫乏,显示了该区地处热带北缘与南亚热带南缘的过渡性质。通过与海南省尖峰岭、江西省庐山和邻近的澳门、深圳和南岭等5个地区植物区系比较,探讨了珠海市与这些地区的相似性和差异特点。     

云南省小黑山自然保护区种子植物区系研究

小黑山自然保护区有野生种子植物170科787属2195种。分析表明该区种子植物区系的地理成分复杂,联系广泛。热带性质的属有506属,占总属数的68.6%,温带性质的属有224属,占总属数的30.4%。热带性质的种890种,占总种数的40.9%,温带性质的种有1267种,占总种数的58.3%。表明该地区植物区系具有明显的亚热带性质,同时深受热带植物区系的影响。植物区系来源主要由东亚成分、热带亚洲成分(印度—马来西亚成分)、中国特有成分三部分融合而成。特有现象明显,有东亚特有科5科,中国特有属6属,中国特有种778种,占种总数的35.8%,而云南特有种有355种,占中国特有种的45.6%。保护区还拥有众多的珍稀濒危植物。     

陕西汉中天坑群维管植物多样性及区系分析

对陕西汉中典型天坑生物多样性进行调查，并在系统收集天坑周边生物多样性研究成果与资料的基础上，对该区维管植物多样性区系进行初步研究。结果表明，汉中天坑群区域有被子植物940种，裸子植物20种，蕨类植物73种。该区植物区系以温带成分为主，兼具热带成分，展示了明显的由暖温带向亚热带过渡的特点，且区系具有一定的古老性。天坑群已发现30种珍稀濒危植物，是现存珍稀濒危植物的“避难所”。该研究对探究天坑群地区生态资源可持续发展利用、天坑生物多样性的保育以及恢复重建等方面具有重要意义。     

横县野生种子植物区系及与附近地区的比较研究

为了解广西横县野生种子植物区系特征,对横县野生种子植物进行了调查分析。结果表明,广西横县有野生种子植物1 269种,隶属于163科658属,以被子植物占优势,而裸子植物则贫乏。在科属种组成上,以大科、区域单型属和少型属为主;生活型组成反映亚热带常绿阔叶林群落特征,藤本植物种类丰富。种子植物地理成分均以热带成分为主,兼备亚热带和温带成分。与邻近地区相比较,横县种子植物区系与广东紫金县相似性较高,区系成分组成则与广东新会区、紫金县相近。因此,横县地区野生种子植物种类丰富,热带性质明显,呈热带至亚热带过渡性质,起源古老,具有一定特有现象,与广东地区联系密切。     

广西拉沟自然保护区种子植物区系研究

通过调查统计,广西拉沟自然保护区共有野生种子植物153科594属985种.种子植物区系组成丰富,地理成分复杂,具有中亚热带向南热带过渡性质.在科、属水平上对植物区系特性进行了统计分析,热带性质均强于温带性质,属的成分以泛热带分布、热带亚洲分布为主.与邻近地区植物区系相比较,拉沟自然保护区与广西大瑶山自然保护区相似性较高,与广西花坪自然保护区相似性较低.     

安徽祁门地区种子植物区系组成及特征

祁门地区位于皖南山区南端,种子植物区系组成丰富,经调查种子植物有147科731属1822种(包括亚种、变种、变型),其中17种为国家级珍稀濒危保护植物。该地区的种子植物优势科为木通科、猕猴桃科、槭树科、金缕梅科、榆科等亚热带和温带分布科。科有11种分布类型,以泛热带分布为主(占51.9%);属有14种分布类型,以北温带分布最多(占20.5%),其中温带性地理成分占55.6%;种有13种分布类型,以中国特有分布最多(占50.8%),其中温带性地理成分占33.1%,因此该区系地理成分复杂,并且具有温带区系性质。此外,该区系起源古老;替代现象和特有植物较为明显。     

安徽鹞落坪自然保护区维管植物区系分析

统计分析了安徽鹞落坪国家级自然保护区的维管植物区系,该区共有维管植物132科、47l属、925种(含种下分类群).科以泛热带分布最多,达38.89%,热带分布多于温带分布(59/29);属以北温带分布最多(26.87%),温带分布多于热带分布(266/134);种以中国特有分布最多(37.40%),温带分布多于热带分布(350/219).将中国特有种划分成8个分布亚型,其中以华东-华中-西南分布最多(156种).研究结果表明,鹞落坪保护区植物种类丰富,地理成分多样,温带成分优势明显,热带成分次之,并且拥有众多特有、珍稀濒危植物.区划上属于华东植物区系.     

广东郁南同乐大山自然保护区种子植物区系研究

通过野外调查与查阅资料,广东郁南同乐大山自然保护区共有野牛种子植物149科542属1 002种.种子植物区系组成丰富,区系地理成分复杂,以南亚热带和热带北缘植物区系地理成分为主.区内珍稀濒危植物多,特有现象较明显,植物区系起源古老.与其它邻近地区植物区系相比较,同乐大山自然保护区种子植物区系与广西龙虎山自然保护区、广东黑石顶自然保护区的相似性较高,与湖南武陵源的相似性较低.     

杭州西湖风景区种子植物区系分析

统计分析了杭州西湖风景区野生种子植物区系,该区共有野生种子植物143科,572属,1111种（含种下分类群）。科的分布区类型以泛热带占优势,达48.9%,热带成分的科远多于温带成分的科（64∶28）;从属的分布区类型看,温带成分的属多于热带成分的属（268∶220）;种的分布区类型中,温带成分的种数远比热带成分的种数多（502∶234）;说明该区亚热带北部区系特征显著。另一方面,本区以单种属和寡种属为主,种的分布区类型中,东亚分布（33.7%）与中国特有分布（32.2%）相当,东亚分布中绝大部分属于中国-日本共有。以中国区系分区标准,将中国特有分布种划分成9个分布亚型,其中以华东-华中-华南分布最多（46.0%）。结果表明该区种子植物丰富、地理成分多样,具有明显的华东东部植物区系特征。     

心脑血管疾病大额住院消费统计分析

通过对医院2004-2006年心脑血管疾病大额住院消费(消费大于50000元,以下简称大额消费)病例发病率高的前五种疾病的构成情况、药费、材料费消耗情况进行分析,认为加强大额病例中发病率高的病种的重点管理,是降低医疗费用的有效途径。建议制定常见病大额病种预定额付费方案和审查报销制度;采用适宜技术;控制药费,防止过度医疗,有效地遏制医疗费用的过快增长。     

Evidence that the C-terminus of OprM is involved in the assembly of the VceAB-OprM efflux pump

Although the architecture of tripartite multiple drug resistance (MDR) efflux pumps of Gram-negative bacteria has been well characterized, the means by which the components recognize each other and assemble into a functional pump remains obscure. In this study we present evidence that the C-terminal domain of the Pseudomonas aeruginosa OprM and the α-helical hairpin domain of Vibrio cholerae VceA play an important role in the recognition/specificity/recruitment step in the assembly of a functional, VceAB-OprM chimeric efflux pump. To our knowledge, this is the first evidence directly linking the C-terminal domain of an outer membrane efflux protein to its recruitment during the assembly of a tripartite efflux pump.     

两个猪苓菌株生长速度及酯酶同工酶比较研究

对不同地理分布的猪苓纯培养菌株进行了种性和酯酶同工酶的比较研究,结果表明,鸡爪苓（Z）纯培养菌株和猪屎苓（ZJ）纯培养菌株的种性有很大不同,两个纯培养菌株的酯酶同工酶酶带类型差异较大,亲缘关系较远。     

Synthesis of modified fragments of fibrinogen and their effect on the activity of proteolytic enzymes

New analogues of the Gly-Pro-Arg and Arg-Gly-Asp fragments of fibrinogen were synthesized: Gly-Pro-Arg-Pro (I), Gly-Pro-Arg-Pro-Met-OMe (II), Gly-Pro-Arg-Pro-Phe (III), Gly-Pro-Arg-Pro-Asp (IV), Gly-Pro-Arg-Pro-Glu (V), and Arg-Asn-Trp-Asp (VI). Their effect on the activity of proteases of various types was studied with the method of lysis of fibrin plates. All the peptides were found to inhibit plasmin activity (by 60–85%) and the γ-subunit of nerve growth factor (by 55–93%). Tetrapeptide (VI) proved to be an effective inhibitor of tissue activator of plasminogen and the γ-subunit of nerve growth factor (by 96 and 93%, respectively). The peptides exerted practically no effect on the activity of urokinase and moderately inhibited the activity of streptokinase [(III), IV), and (VI)], papain [(I), (II), IV), and (VI)], subtilisin [(V) and (VI)], α-chymotrypsin [(III), (V), and VI)], and Bacillus subtilis metalloprotease (VI). They inhibit trypsin [except for (I) and (III)] when applied on fibrin plates at a concentration of 1 × 10^?2 M, while, at the concentration of 1 × 10^?3 M, (I) and (II) induced an increase in proteolytic activity by 35 and 47%, respectively.     

Studies on the energy coupling sites of photophosphorylation IV. The relation of proton fluxes to the electron transport and ATP formation associated with Photosystem II

1. By using dibromothymoquinone as the electron acceptor, it is possible to isolate functionally that segment of the chloroplast electron transport chain which includes only Photosystem II and only one of the two energy conservation sites coupled to the complete chain (Coupling Site II, observed P/e₂ = 0.3–0.4). A light-dependent, reversible proton translocation reaction is associated with the electron transport pathway: H₂O → Photosystem II → dibromothymoquinone. We have studied the characteristics of this proton uptake reaction and its relationship to the electron transport and ATP formation associated with Coupling Site II.

2. The initial phase of H⁺ uptake, analyzed by a flash-yield technique, exhibits linear kinetics (0–3 s) with no sign of transient phenomena such as the very rapid initial uptake (“pH gush”) encountered in the overall Hill reaction with methylviologen. Thus the initial rate of H⁺ uptake obtained by the flash-yield method is in good agreement with the initial rate estimated from a pH change tracing obtained under continuous illumination.

3. Dibromothymoquinone reduction, observed as O₂ evolution by a similar flash-yield technique, is also linear for at least the first 5 s, the rate of O₂ evolution agreeing well with the steady-state rate observed under continuous illumination.

4. Such measurements of the initial rates of O₂ evolution and H⁺ uptake yield an H⁺/e⁻ ratio close to 0.5 for the Photosystem II partial reaction regardless of pH from 6 to 8. (Parallel experiments for the methylviologen Hill reaction yield an H⁺/e⁻ ratio of 1.7 at pH 7.6.)

5. When dibromothymoquinone is being reduced, concurrent phosphorylation (or arsenylation) markedly lowers the extent of H⁺ uptake (by 40–60%). These data, unlike earlier data obtained using the overall Hill reaction, lend themselves to an unequivocal interpretation since phosphorylation does not alter the rate of electron transport in the Photosystem II partial reaction. ADP, P_i and hexokinase, when added individually, have no effect on proton uptake in this system.

6. The involvement of a proton uptake reaction with an H⁺/e⁻ ratio of 0.5 in the Photosystem II partial reaction H₂O → Photosystem II → dibromothymoquinone strongly suggests that at least 50% of the protons produced by the oxidation of water are released to the inside of the thylakoid, thereby leading to an internal acidification. It is pointed out that the observed efficiencies for ATP formation (P/e₂) and proton uptake (H⁺/e⁻) associated with Coupling Site II can be most easily explained by the chemiosmotic hypothesis of energy coupling.     

林带阻力系数与透风系数关系的理论分析

根据冲量定理分析了林带对气流的阻力,首次得到了林带阻力系数的估算模式（Ｃｄ＝（１．８＋０．２α）（１－α）ｓｉｎ２ω,并利用有关文献发表的资料进行了验证．文章还对来流平行林带时林带对气流的阻力进行了讨论,指出来流平行林带时林带对气流的阻力仅为来流垂直林带时林带对气流阻力的０．７—１．１％,可以不予考虑．     

Photoinactivation of Photosystem II in leaves

Photoinactivation of Photosystem II (PS II), the light-induced loss of ability to evolve oxygen, inevitably occurs under any light environment in nature, counteracted by repair. Under certain conditions, the extent of photoinactivation of PS II depends on the photon exposure (light dosage, x), rather than the irradiance or duration of illumination per se, thus obeying the law of reciprocity of irradiance and duration of illumination, namely, that equal photon exposure produces an equal effect. If the probability of photoinactivation (p) of PS II is directly proportional to an increment in photon exposure (p = kΔx, where k is the probability per unit photon exposure), it can be deduced that the number of active PS II complexes decreases exponentially as a function of photon exposure: N = N_oexp(−kx). Further, since a photon exposure is usually achieved by varying the illumination time (t) at constant irradiance (I), N = N_oexp(−kI t), i.e., N decreases exponentially with time, with a rate coefficient of photoinactivation kI, where the product kI is obviously directly proportional to I. Given that N = N_oexp(−kx), the quantum yield of photoinactivation of PS II can be defined as −dN/dx = kN, which varies with the number of active PS II complexes remaining. Typically, the quantum yield of photoinactivation of PS II is ca. 0.1μmol PS II per mol photons at low photon exposure when repair is inhibited. That is, when about 10⁷ photons have been received by leaf tissue, one PS II complex is inactivated. Some species such as grapevine have a much lower quantum yield of photoinactivation of PS II, even at a chilling temperature. Examination of the longer-term time course of photoinactivation of PS II in capsicum leaves reveals that the decrease in N deviates from a single-exponential decay when the majority of the PS II complexes are inactivated in the absence of repair. This can be attributed to the formation of strong quenchers in severely-photoinactivated PS II complexes, able to dissipate excitation energy efficiently and to protect the remaining active neighbours against damage by light.     

The detection of salivary enzymes of phytophagous Hemiptera: a compilation of methods

The role of Hemipteran saliva and salivary enzymes is central to an understanding of the etiology of damage that these insects cause to plants. The dilute nature of the salivary secretions and the minute quantities in which they are often obtainable have made analysis and detection of salivary components very difficult. Such investigations in this laboratory have led us to formalise the techniques involved and we believe that the compilation of these methods presented herein may be useful to other research workers in this area. Methods are described for acid and alkaline phosphatase, esterase, /S-glucosidase, carbohydrases, invertase, amylase, proteinase, pectinase, cellulase, catalase, peroxidase, catechol oxidase, superoxide dismutase and ascorbic oxidase.     

2种嵩草属植物形态特征对生境干旱化的响应

该研究于西藏自治区东南部的东达山高山草甸沿生境干旱化梯度设置10个样地,采用线性回归方法分析优势种高山嵩草(Kobresia pygmaea)和矮生嵩草(K.humilis)叶片数量与其它构件数值(分株数量、茎基直径、根系数量和根系长度)之间的关系,并采用线性回归斜率测度分株功效、叶片萌生能力、根系分生功效和根系伸长功效,以探讨嵩草的分株能力、茎基生长和根系生长对生境干旱化过程的响应机制。结果显示:(1)2种嵩草植物的叶片数量与4种构件数值均为显著线性正相关关系。(2)随着生境干旱化程度增加,高山嵩草分株数量增加,矮生嵩草分株受干旱抑制程度高,分株数量呈下降趋势;2种嵩草分株功效下降,即单株叶片数量因干旱化程度增加而减少。(3)2种嵩草的茎基直径、叶片萌生能力随着生境干旱化程度增加而下降;高山嵩草叶片萌生能力的变化与生境干旱化梯度一致,具有连续性;矮生嵩草叶片萌生能力对生境干旱化的适应性弱,干旱到一定程度发生骤降。(4)随着生境干旱化,高山嵩草的根系数量和长度均增加,矮生嵩草根系长度增加,但数量却无规律变化;2种嵩草的根系分生功效和根系伸长功效均下降。研究表明:嵩草属植物分布的最适宜生境为表面稍有积水的沼生生境。为适应生境干旱化,高山嵩草降低叶片萌生率以减少蒸腾作用,增加分株数量以增强对空间的占有能力,并增加根系数量和长度来提高对土壤水分的吸收能力,因此对干旱有较强适应性且分布范围广;矮生嵩草只通过降低叶片萌生率,增加根系长度响应干旱化生境,其分布范围较窄。     

民勤绿洲边缘地下水位变化对植物种群生态位的影响

在民勤绿洲边缘,利用空间区域不同地下水位(湖区8～12m,泉山区15～17m,坝区20～23m)和时间序列(1984～1992年)民勤沙井子地区地下水位下降(7.45～11.65m)梯度,研究地下水位下降对荒漠植物种群生态位的影响。结果表明:空间区域地下水位下降,植物种群生态位宽度均减小,种群退化;时间序列地下水位下降,白刺种群在扩展,其它植物种群在退化。白刺种群生态位宽度在民勤绿洲边缘荒漠植物群落中最大,是该区的建群种。由于白刺种群在地下水位7.45～11.65m范围内扩展,民勤绿洲生态环境治理中地下水位达到该范围是一个主要目标。