两型豆花粉和叶表皮的扫描电镜观察

两型豆花粉和叶表皮在扫描电镜下的形态特征：花粉近球形至矩球形,三孔沟,外壁表面较粗糙,侧壁具疣状突起至块状突起,极面具粗网状纹饰,但两型豆祖山居群属于萌发沟不明显型,两型豆燕塞湖居群属于萌发沟明显型。叶表皮细胞不规则,排列紧密,叶脉表皮细胞长圆柱形,长轴与叶脉平行,角质膜薄,表皮毛均为单细胞非腺毛,气孔器仅分布在下表皮,属于平列型,偶见不规则型。表皮毛和气孔器在叶片上分布不均匀,两型豆祖山居群叶表皮毛和气孔器的平均密度大于两型豆燕塞湖居群叶表皮毛和气孔器的平均密度,自然生长的两型豆叶表皮毛和气孔器的平均密度大于遮光条件下的两型豆。     

Equipoise, knowledge and ethics in clinical research and practice

It is widely maintained that a clinical trial is ethical only if some form of equipoise between the treatments being compared obtains. To be in equipoise between two treatments A and B is to be cognitively indifferent between the statement 'A is strictly more effective than B' and its negation. It is natural to claim that equipoise regarding A and B is necessary for randomised assignment to treatments A and B to be beneficent and non-maleficent and is sufficient for such an assignment to be fair. Cashing this out precisely is difficult, and various forms of equipoise have been discussed which consider whose equipoise is relevant to the decision. This is to make judgement of equipoise something to be managed socially, while its prima facie significance is supposedly cognitive. Recent reconstructions of equipoise-like concepts in epistemology give clues about how to understand equipoise cognitively. In this paper I examine some of this work and discuss how successful it has been. I suggest that while this work is promising, it still has far to go, and that while equipoise remains the best theory we have of the cognitive justification for clinical trials, it is nonetheless incoherent.     

Oxidation of glycine by Phaseolus leghaemoglobin with associated catabolic reactions at the haem.

Leghaemoglobin from the root nodules of kidney bean (Phaseolus vulgaris) reacts in alkaline glycine solutions as a glycine oxidase in a reaction that may also be regarded as a coupled oxidation. Leghaemoglobin is reduced to the ferrous form by glycinate, the oxygen complex is formed, and finally the haem is attacked to yield a green reaction product. Glycine is simultaneously oxidized to glyoxylate, and hydrogen peroxide is generated. The initial velocity of the formation of the green product is proportional to the concentrations of leghaemoglobin and glycine, and the optimum pH for the reaction is 10.2. The green product is not formed if carbon monoxide, azide of imidazole is bound to the haem, whereas oxidation of glycine to glyoxylate is not inhibited by azide and not essentially by carbon monoxide. Haem breakdown is activated by digestion of leghaemoglobin by carboxypeptidase, and partly inhibited by catalase and superoxide dismutase.     

山西省种子植物多样性分布格局与环境关系的研究

采用除趋势对应分析(DCA)、典范对应分析(CCA)对山西省12个区域的种子植物多样性及区系地理成分的分析表明,全省种子植物多样性格局可分为3类:第1类为山西省西部和北部山地,热量相对较低,海拔较高,降水随海拔升高而增加,气候垂直变化明显,小生境类型较多,分类强度大,区系成分中以北温带、旧世界温带属占绝对优势。第2类为山西中部地区,地势相对较低,水热条件中等,北温带成分仍为优势种,但旧世界温带分布属和泛热带分布属的比例增加。第3类为山西南部和东南部山区,降水量相对较高,但温度也高,蒸发量大,属的区系成分中以北温带成分为优势,但第二优势成分为泛热带亚洲成分,与前2类地区相比,热带成分明显增加。     

矮沙冬青雌配子体及胚胎发育研究

矮沙冬青子房单心皮1室,边缘胎座,弯生胚珠,胚珠具双珠被、厚珠心。大孢子孢原细胞发生于珠心表皮下,大孢子母细胞减数分裂形成直线排列的四分体,合点端大孢子具功能,并按蓼型胚囊发育,雌配子体成熟于4月中旬。双受精后,胚乳发育为核型。在矮沙冬青大孢子发生、雌配子体和胚胎发育过程中未发现异常现象,因此认为矮沙冬青濒危不存在雌性生殖结构与发育过程异常的内在因素。     

清栓酶治疗脑血栓冠心病微循环变化初步观察

本文报导40例脑心血管疾病在清栓酶治疗前后进行甲皱微循环对比观察,其中脑血栓组20例,冠心病组20例,两组均在清栓酶治疗2～3疗程后复查,分别对其甲皱微循环微血管袢的形态及功能,血液流态和微血管周围变化等三方面进行治疗前后对比观察,结果发现,治疗前甲皱微循环改变是明显的,临床症状较重,治疗后甲皱微循环障碍均得到了明显改善,临床症状也随着减轻或消失。治疗前后比较,其差异有显著的意义 P<0.05,P<0.01.从临床对比观察所见,脑心血管疾病的微循环改变与病情有关,其改变与病情轻重相吻合,与疾病转归相一致,提示微血管病变是动脉硬化临床可识别的象征.微循环障碍与疾病的发生发展有着内在联系,是脑心血管疾病的病因和发病的中间环节.治疗后微循环障碍的明显改善,提示清栓酶有着较好的改善微循环的功能.     

羚牛(Budorcas taxicolor)部分脏器特点的观察

本文对2只羚牛的雌性生殖器官及肝、肾、脾等脏器进行了形态描述,并与黄牛及羊的相应器官进行了比较,为探讨羚牛的分类地位提供了解剖学资料。     

Morphological appraisal of Collembola phylogeny with special emphasis on Poduromorpha and a test of the aquatic origin hypothesis

Phylogenetic relationships within Collembola were determined through the cladistic analysis of 131 morphological characters and 67 exemplar taxa representing the major families of the group, with special emphasis on Poduromorpha. The results show that the order Poduromorpha is monophyletic and the sister group to the remaining Collembola, with Entomobryomorpha monophyletic and the sister group to the clade Neelipleona + Symphypleona. In Entomobryomorpha, Actaletidae is the sister group of the remaining families. In Poduromorpha, Tullbergiinae is monophyletic as well as Onychiurinae and the group Tetrodontophorinae + Onychiurinae which is the sister group of the remaining Poduromorpha; Tetrodontophorinae is paraphyletic; Onychiuridae is polyphyletic; Isotogastruridae is not an intermediate between Poduromorpha and Entomobryomorpha, it is the sister group of Tullbergiinae; Odontellidae is monophyletic and the sister group to the clade Neanuridae + Brachystomellidae; in Neanuridae, Frieseinae and the group Pseudachorutinae + Morulinae + Neanurinae are monophyletic; Morulinae is the sister group of Neanurinae; Pseudachorutinae is paraphyletic; Hypogastruridae is polyphyletic; Podura aquatica (Poduridae) is not 'primitive', it clusters with the genera Xenylla and Paraxenylla in Hypogastruridae. On the basis of these relationships and the position of the aquatic species, the most parsimonious hypothesis is a terrestrial edaphic origin for the springtails.     

Carbohydrate metabolism in Musa paradisiaca

Considerable variations exist in the content of glucose, fructose, sucrose, starch and protein and in the activities of enzymes involved in carbohydrate metabolism between different parts of the banana plant (Musa paradisiaca). Sucrose synthetase is present in the highest concentration in rootstock and fruit pulp, and sucrose phosphate synthetase in the pseudostem. The highest ratio of the activity of sucrose phosphate synthetase to sucrose synthetase is found in leaves. Acid invertase is present in leaves, leaf-sheath and fruit pulp and is not demonstrable in rootstock and pseudostem. Neutral invertase activity is high in pseudostem and leaf-sheath. Starch phosphorylase is largely concentrated in fruit pulp and rootstock. The maximum activity of ATP:d-phosphoglucose (ADPG) pyrophosphorylase is found in rootstock. β-Amylase is not demonstrable in rootstock and is largely concentrated in leaf-sheath. Hexokinase is most active in rootstock and the lowest in leaves. Acid phosphatase and alkaline phosphatase activity is highest in fruit pulp and pseudostem. Glucosephosphate isomerase is most active in the rootstock and lowest in the leaves.     

扬子鳄视觉器官组织学研究

本文用光镜和电镜研究了扬子鳄(Alligator sinensis)的组织学,同时测量了其眼球的一些光学参数.扬子鳄眼球呈扁圆球形,角膜径与球径的比值为1:1.44;晶状体与角膜的比值为1:1.40。角膜内具鲍氏膜;虹膜内的括约肌、睫状体内的睫状肌均属横纹肌,视细胞椭圆体内线粒体嵴突与线粒体长轴相平行,这与报道的其它鳄类不同。虹膜内未见扩瞳肌纤维,角膜缘缺巩膜小骨片,晶状体环垫薄,因而其视觉调节能力仍然很弱。视网膜中视细胞由视杆细胞、单锥细胞、双锥细胞组成,其中以视杆细胞占多数。视细胞与神经节细胞核比值平均为2.5:1,表明扬子鳄的组织结构与其弱光视觉相适应。     

Estimation of distal arm joint angles from EMG and shoulder orientation for transhumeral prostheses

In this paper, we quantify the extent to which shoulder orientation, upper-arm electromyography (EMG), and forearm EMG are predictors of distal arm joint angles during reaching in eight subjects without disability as well as three subjects with a unilateral transhumeral amputation and targeted reinnervation. Prior studies have shown that shoulder orientation and upper-arm EMG, taken separately, are predictors of both elbow flexion/extension and forearm pronation/supination. We show that, for eight subjects without disability, shoulder orientation and upper-arm EMG together are a significantly better predictor of both elbow flexion/extension during unilateral ($R^2=0.72$) and mirrored bilateral ($R^2=0.72$) reaches and of forearm pronation/supination during unilateral ($R^2=0.77$) and mirrored bilateral ($R^2=0.70$) reaches. We also show that adding forearm EMG further improves the prediction of forearm pronation/supination during unilateral ($R^2=0.82$) and mirrored bilateral ($R^2=0.75$) reaches. In principle, these results provide the basis for choosing inputs for control of transhumeral prostheses, both by subjects with targeted motor reinnervation (when forearm EMG is available) and by subjects without target motor reinnervation (when forearm EMG is not available). In particular, we confirm that shoulder orientation and upper-arm EMG together best predict elbow flexion/extension ($R^2=0.72$) for three subjects with unilateral transhumeral amputations and targeted motor reinnervation. However, shoulder orientation alone best predicts forearm pronation/supination ($R^2=0.88$) for these subjects, a contradictory result that merits further study.     

Homology and function in the wings of Heteroptera

Abstract. The homology of veins and other wing characters in Heteroptera is reviewed in the light of palaeontology and new functional studies. A cladogram is given for the higher taxa of Hemiptera. It is probable that the vannus is an autapomorphy of Auchenorrhyncha+Heteropteroidea; that the leading edge vein of heteropteran fore- and hindwings is C+Sc; that Rs cannot be distinguished from R; that the hamus is part of M; that the glochis is a secondary structure. The difficulty of defining a vein is stressed. The functional significance of the hemielytron, cuneal fracture and longitudinal flexion lines is discussed. A preliminary ground-plan for Heteroptera wings is presented.     

Antidiuretic mechanism in Rhodnius prolixus (Stal, 1859) (Hemiptera, Reduviidae)

An antidiuretic mechanism is proposed for Rhodnius prolixus, whose activity is manifested when the diuretic phase has terminated and is maintained until the insect has fed again. Presumably this mechanism acts at the level of the proximal rectal sphincter and is inhibited by ingestion, mechanical distension of the gut and central disinhibition by decapitation. It is suggested that the antidiuretic activity is maintained by the nervous system and is modified when there is distention of the gut or when the nervous signal is interrupted by decapitation. It is demonstrated that the excretion of urine in R. prolixus is not controlled exclusively by the diuretic hormone, but rather that factors not linked to the haemolymph maintain the insects in a diuretic or nondiuretic state.     

短柄五加大,小孢子发生和雌,雄配子体发育的研究

短柄五加花药５枚,每个花药四个花粉囊。小孢子母细胞减数分裂时,胞质分裂为同时型,产生正四面体形的四分体。花药壁由表皮、药室内壁、中层和绒毡层四层细胞组成,其发育类型为双子叶型。腺质绒毡层,其细胞为二核。三细胞型花粉。子房５室,每室两个胚珠,上胚珠败育,下胚珠可育。下胚珠倒生,具单珠被,厚珠心。大孢子母细胞减数分裂形成线性排列的四个大孢子,雌配子体发育属蓼型。开花当天,花粉散开,雌配子体尚未成熟,处     

红腹锦鸡血细胞的光镜和扫描电镜观察

为了探讨红腹锦鸡(Chrysolophus pictus)血细胞的形态特征,为生理学研究提供生物学基础资料,利用光镜和扫描电镜观察了红腹锦鸡血细胞的形态特征。结果表明,红腹锦鸡红细胞呈椭圆形或扁圆形,表面光滑,具核;白细胞为球形,体大,淋巴细胞表面有绒毛状突起,嗜中性粒细胞核一般分2~5叶,嗜酸性粒细胞核一般分2叶,嗜碱性粒细胞核分2~3叶,单核细胞表面粗糙不平,核大,呈肾形或圆形;凝血细胞呈球形或不规则形。     

黍稷的名实考证及规范

黍稷是起源于中国最古老的作物,糯者为黍,粳者为稷。长期以来对黍稷的称谓一直不能统一,特别是对稷的称谓在农史界一直争论不休,难以定论。本文从黍稷的起源演化过程、细胞学和遗传学的研究、黍稷是人类最早驯化的作物、我国甲骨文和古农书的记载等方面,论证了黍稷的起源早于粟。并以此为据,进一步辩证了稷不是粟,同时指出将黍稷称为软糜和硬糜、糜黍、糜子、黍子等不同称谓的不足之处,进而认为以黍稷作为规范称谓为好。     

Control of glucose metabolism in the perinatal period

The central importance of glucose as a fuel for energy metabolism and growth of the fetus is clear as is the role of insulin in coordinating its utilisation by many fetal tissues. What is less clear is the qunatitative nature of the interaction between the fetus and placenta in organising glucose metabolism. Increasingly there is evidence that the fetus coordinates some of the supply of glucose to the placenta and that this is particularly important when uterine blood flow is reduced. It is unclear how this is regulated, but substrate cycles of glucose and lactate appear to make a significant contribution to carbohydrate metabolism in fetus and placenta. Another area as yet unresolved in the control of fetal glucose metabolism is the coordination of the changes that occur around the time of birth. Notable of these is the activation of glycogen mobilisation and of glucose synthesis and changes in the setting of glucose regulatory mechanism. These are briefly reviewed.     

Vanadate-stimulated NADH oxidation in plasma membrane

The rate of NADH oxidation with oxygen as the acceptor is very low in mouse liver plasma membrane and erythrocyte membrane. When vanadate is added, this rate is stimulated 10- to 20-fold. The absorption spectrum of vanadate does not change with the disappearance of NADH. The reaction is inhibited by superoxide dismutase, and there is no activity under an argon atmosphere. This indicates that oxygen is the electron acceptor and the reaction is mediated by superoxide. The vanadate stimulation is not limited to plasma membrane. Golgi apparatus and endoplasmic reticulum show similar increase in NADH oxidase activity when vanadate is added. The endomembranes have significant vanadate-stimulated activity with both NADH and NADPH. The vanadate-stimulated NADH oxidase in plasma membrane is inhibited by compounds, which inhibit NADH dehydrogenase activity: catechols, anthracycline drugs and manganese. This activity is stimulated by high phosphate and sulfate anion concentrations.     

黑鸢消化系统形态学的初步研究

对黑鸢消化系统的形态学作了初步的观察与研究,结果表明：黑鸢舌尖钝圆,舌根分叉,叉粘膜上具有尖端指向后方的栉状突;食管宽而扁,无明显可见的嗉囊;肌胃无明显的类角质膜;肠道长是体长2．3倍,小肠较发达,K1275mm,古肠道总长的93．6％,具有不发达的双侧盲肠：胰腺短而厚、并与蛇雌、毛脚鸢的消化系统进行了比较。     

爪鲵消化系统的解剖学和组织学初步研究

本文报道了爪鲵消化系统的形态学和组织学结构特点。爪鲵口腔底部具有肌肉质的舌,食管很短,胃是呈纺锤形的长囊,胃壁较厚,粘膜厚,胃腺发达。消化管肌层皆为平滑肌,环肌明显多于纵肌。肝脏较大,分左、中、右三叶;有胆囊;胰腺长带状,胰管与胆管汇合后与小肠最前部的十二指肠相连。