Stabilité de l'espèce et évolution: La théorie de l'équilibre intermittent («Punctuated equilibrium)

Paleontologists' traditional conceptions on evolution do not seem to be in perfect accord with these of biologists. The gradual phyletism is compatible neither with E. Mayr's model of the Founder, nor with the actual stability of most of the paleontological species. The punctuated equilibrium model proposed by N. Eldredge & S.J. Gould offers a solution which integrates both paleontological observations and the data of modern biology.     

艾叶多糖提取率影响因素分析及提取条件优化

艾叶是菊科(Compositae)植物艾(Artemisia argyi Lévl.et Vant.)的干燥叶,为常用中药材之一,药用历史悠久,具有苦燥辛散、理气血、温经脉、逐寒湿、止冷痛等功效,为重要的妇科用药,可用于治疗脘腹冷痛、经寒不调、宫冷不孕等证.此外,利用艾叶预防瘟疫已有悠久的历史.现代药理研究表明:艾叶是一种广谱抗菌抗病毒中药,对多种病毒和细菌有抑制和杀伤作用,对呼吸系统疾病以及心血管等慢性疾病有一定的防治作用[1-3].因此,将艾叶中的有效成分分别提取和纯化并加以分析以及功能检测,具有深远意义.     

Selenetherium kolleensis nov. gen. nov. sp. : un nouveau Proboscidea (Mammalia) dans le Pliocène tchadien

The survey of proboscides remains recovered from Kollé quarries (Northern Chad) gives evidence of a new taxa of Elephantidae. The anatomical and cladistic analysis permit to consider this new taxa as the sister group of Stegotetrabelodontinae. This new discovery reinforces, once again, the remarkable biodiversity of this group. The proboscidean's association observed in these layers and the evolutionary state of teeth permit us to date the Kollé fossiliferous sector close to the early Pliocene.     

Fuciniceras paradoxus nov. sp. (Harpoceratinae, Ammonitina) du Domérien portugais. Réflexion sur le sens taxonomique d’un assemblage paradoxal de caractères

A new ammonite (Fuciniceras paradoxus) is described here. This Lower Domerian species is based on a recently revised collections which came from the Maria Pares section (Rabaçal area, South of Coimbra, Portugal). Curiously, shell of F. paradoxus bears both diagnostic traits for the genus Protogrammoceras SPATH (e.g. acute ogival ventral area) and Fuciniceras HAAS (e.g. angulirursiradiate rib). Thus, the new species can be viewed as a morphological puzzle and as a challenge for taxonomists. The amazing collection of morphological traits previously suspected as highly improbable because of biomechanical constraints (1) confirms the inadequacy of the traditional use of the genera Protogrammoceras and Fuciniceras, (2) refutes the idea of a univocal biomechanic link between the ventral area morphology and the ventral segment of ribs. If this analysis mainly concern the Harpoceratinae subfamily, its generalisation can also be interesting for other ammonites or molluscan groups.     

越冬代亚洲玉米螟成虫发生动态及其与温度关系初探——以通辽市开鲁县为例

为明确亚洲玉米螟越冬代成虫发生动态及其与温度的关系,于2007-2016年利用频振式杀虫灯结合当地气象数据进行系统调查与分析。结果表明,自然条件下内蒙古通辽地区越冬代玉米螟成虫始见期在6月初(6月5日左右),高峰期在6月下旬(6月26日左右),终见期为7月中旬(7月14日左右),整个成虫期有效温度累积范围在150.0℃~750.0℃之间,高峰期集中在350.0℃~450.0℃的范围内。总的来看,越冬代成虫始见期与高峰期与吉林省中部地区大体相同,终见期稍晚于吉林中部地区但早于黑龙江哈尔滨地区。通辽与吉林中部地区越冬代成虫期(均40 d左右)约比黑龙江哈尔滨地区短10 d。可见,各地越冬代玉米螟成虫发生期的早晚和持续时间长短因地而异,同一地区受年份间的气温变化其也会出现差异。     

卡介苗荚膜阿拉伯甘露聚糖的提纯鉴定及其免疫调节功能的初步研究

确定卡介苗(BCG)中荚膜中糖成分阿拉伯甘露聚糖(AM)的功能。

本研究从我国目前普遍使用的BCG中, 利用氯仿甲醇抽提方法分离纯化荚膜AM, 经AM单克隆抗体鉴定后, 腹腔注射BCG致敏小鼠, 体内外评价AM的免疫调节功能。

AM能在小鼠体内增强BCG诱导的迟发型超敏反应(P < 0.01), 体外免疫指标检测发现AM提高小鼠脾细胞Th1类细胞因子IFN-γ和TNF-α的表达水平(P < 0.05)。

BCG的荚膜AM是潜在的保护性抗原, 并为优化BCG提供理论依据。