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1.
The Nanpanjiang Limestone of eastern Yunnan has long been known as one of theimportant Devonian beds in South China.It was first proposed by Prof.Y.C.Sun in1943,and tentatively included in the upper member of the Miaokaoshan formation ofEarly Devonian age with Gypidula pseudogleata Hall as a leading fossil.Since thenmost geologists and palaeontologists have followed Sun's assignment,while few othershave held it to be Early Middle Devonian.At the type locality near Poshi districtalong the Nanpanjiang Valley the Nanpanjiang Limestone is composed of yellowish-greyor dark grey limestone with an approximate thickness of 40—70 meters,and is overlainby the Bothriolepis-bearing beds of Lunghuashan formation.  相似文献   

2.
Three new genera of the spider family Nesticidae, Hamus gen. nov., Nescina gen. nov. and Wraios gen. nov., are reported. Three new species, Hamus bowoensis sp. nov., Nescina minuta sp. nov. and Wraios longiembolus sp. nov., showing remarkable characters in palpal and epigynal morphology, are described based on specimens collected in Tibet and Yunnan, China. All the type specimens are deposited in the Institute of Zoology, Chinese Academy of Sciences(IZCAS) in Beijing.  相似文献   

3.
A new species of the genus Odorrana is described from a completely dark karst cave of northeastern Guangxi, southern China. The new species, Odorrana lipuensis sp. nov., can be distinguished from its congeners by a combination of the following characters: medium size(SVL: 40.7–47.7 mm in males, 51.1–55.4 mm in females); tips of all but first finger expanded with circummarginal grooves; smooth, grass-green dorsum with irregular brown mottling; pineal body invisible; throat to upper abdomen with gray mottling; dorsal surfaces of limbs with brown bands; dorsolateral fold absent; tiny spinules on lateral body, temporal region, and anterior and posterior edge of tympanum; white nuptial pad present on finger I; males lacking vocal sacs; females having creamy yellow eggs, without black poles. Uncorrected sequence divergences between O. lipuensis sp. nov. and all homologous 16 S rRNA sequences of Odorrana available on Gen Bank is equal to or greater than 4.9%. Currently, the new species is only known from the type locality.  相似文献   

4.
Yang  Yaping  Liu  Jieqiong  Peng  Min  Su  Fengxi  Xie  Xiaoming  Liu  Zhenzhen  Wu  Jundong  Wei  Wei  Zhou  Dongxian  Li  Weiwen  Zhang  Ailing  Su  Guosen  Yang  Weixiong  Chen  Jishang  Ma  Dekui  Cai  Yongguang  Chen  Kai  Zhu  Liling  Liu  Qiang  Song  Erwei 《中国科学:生命科学英文版》2020,63(9):1417-1420
正Dear Editor,Breast cancer is now the most frequently diagnosed cancer and is the fifth leading cause of cancer-related death in Chinese women. Therefore, the burden of breast cancer in China is gradually increasing. According to figures released by the Chinese Cancer Center in 2018, the number of newly diagnostic breast cancer is about 278,900 cases, accounting for 16.51%of all women who were diagnosed with the first primary malignant tumors; and 66,000 cases of breast cancer died in 2014 (Chen et al., 2016).  相似文献   

5.
《动物学研究》2016,(6):361-365
From 2 to 4 November,2016,the 4th Symposium on Animal Models of Non-Human Primates (NHP) was held in Kunming,Yunnan,China.This meeting was organized by the Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences (CAS) & Yunnan Province,Kunming Primate Research Center (KPRC),Zoological Research,and Kunming Institute of Zoology (KIZ),CAS.  相似文献   

6.
Yunnan is a province rich in flora.There are about 13,000 species of 1,984genera among 240 families(230 families of Angiospermae according to Hutchin-son's system and 10 families of Gymnospermae)in Yunnan.The number offamily in Yunnan is about 79.73% of 301 families in China,the number of genera64.88% of 3,058 genera in China,and the number of species 52% of 25,000species in China.The four very big families such as Orchidaceae,Compositae,  相似文献   

7.
《遗传学报》2007,34(8):764-764
"Forum on Genetics Progress and Human Health" will be held at Yunnan University in Kunming, Yunnan Province, China, in November, 2007. The forum focuses on the current progress and future directions in all major aspects of human genetics and medical genetics. The submitted papers written in English will be considered for publication in Journal of Genetics and Genomics after peer-review and papers in Chinese in Hereditas (Beijing). Papers in the following areas are encouraged for submission and outstanding papers will be selected for oral presentation in the forum.  相似文献   

8.
《遗传学报》2007,34(6):572-572
"Forum on Genetics Progress and Human Health" will be held at Yunnan University in Kunming, Yunnan Province, China, in November, 2007. The forum focuses on the current progress and future directions in all major aspects of human genetics and medical genetics. The submitted papers written in English will be considered for publication in Journal of Genetics and Genomics after peer-review and papers in Chinese in Hereditas (Beijing). Papers' in the following areas are encouraged for submission and outstanding papers will be selected for oral presentation in the forum.  相似文献   

9.
Obstructive sleep apnea syndrome (OSAS) is characterized by recurrent collapses of the upper airway, which lead to repetitive transient hypoxia, arousals and finally sleep fragmentation. Both anatomical and neuromuscular factors may play key roles in the pathophysiology of OSAS. The purpose of this paper was to study the control mechanism of OSAS from the mechanical point of view. A three-dimensional finite element model was developed, which not only reconstructed the realistic anatomical structure of the human upper airway, but also included surrounding structures such as the skull, neck, hyoid, cartilage and soft tissues. The respiration process during the normal and apnea states was simulated with the fluid-structure interaction method (FSI) and the computational fluid dynamics method (CFD). The airflow and deformation of the upper airway obtained from the FSI and the CFD method were compared and the results obtained under large negative pressure during an apnea episode were analyzed. The simulation results show that the FSI method is more feasible and effective than the CFD method. The concave configuration of the upper airway may accelerate the collapse of the upper airway in a positive feedback mechanism, which supplies meaningful information for clinical treatment and further research of OSAS.  相似文献   

10.
In hermaphroditic plants, female reproductive success often varies among different positions within an inflorescence. However, few studies have evaluated the relative importance of underlying causes such as pollen limitation, resource limitation or architectural effect, and few have compared male allocation. During a 2-year investigation, we found that female reproductive success of an acropetally flowering species, Corydalis remota Fisch. ex Maxim. var. lineariloba Maxim. was significantly lower in the upper late developing flowers when compared with the lower early flowers. Supplementation with outcross pollen did not improve female reproductive success of the upper flowers, while removal of the lower developing fruits significantly increased female reproductive success of the upper flowers in both years, evidencing resource limitation of the upper flowers. Female production in upper flowers was greatly improved by simultaneous pollen supplementation of the upper flowers and removal of the lower fruits, suggesting that, when resources are abundant, pollen may limit the female reproductive success of the upper flowers. The less seed mass in the upper flowers didn't increase in all treatments due to architecture. In the upper flowers, ovule production was significantly lower and the pollen : ovule ratio was significantly higher. These results suggest that male-biased sex allocation in the upper flowers may lead to increased male reproductive success, whereas the lower flowers have higher female reproductive success.  相似文献   

11.
高原鼠兔种群的性比   总被引:6,自引:1,他引:5  
The sex ratio (♂ / ♀ ) of plateau pika's (Ochotona curzoniae) population was studied by re-captured method in the region of the Haibei Mpine Meadow Ecosystem Research Station, Northwest Institute of Plateau Biology, the Chinese Academy of Sciences from April of 2001 to August of 2002. The result showed that there was no significant difference from 1:1 in adult's sex ratio in whole breeding season, whereas the sex ratio of juvenile had some fluctuations among different age stages. The sex ratio of the second litter varied significantly from embryo to 60-day-old, but no difference at the first and the third litter. We concluded it was caused by conflict between maternal strategy and juvenile's strategy. No significant differences of sex ratio were found both in adult and juvenile between 2001 and 2002. The sex ratio of plateau pika before and after overwintering did not vary. In summary,we proposed that sex ratio of plateau pika's population was not influenced by exogenous factors, but some serf-regulation mechanisms may be involved.  相似文献   

12.
The new genus Yushanograptus described in the present paper is a monotypic genuswith Yushanograptus separatus gen.et sp.nov.as the genotype which is represented by5 specimens securd by one of the writers(Han)in the summer of 1961 from the NingkuoShale at the locality near Lijiapeng of the Yushan district,northeastern Jiangxi(Kiangsi)Province(Field No.F61001).The marked features of the new genus are the two long and slender primary stipesand the Goniograptid type in branching.The young forms of this new graptolite bear astriking resemblance to the slender Didymograpti,such as Didymograptus gracilis T(?)rn-quist,D.cognatus Harris et Thomas etc.The same is the case in Zygograptus,particul-arly in Zygograptus irregularis Harris et Thomas.In the mode of branching of the  相似文献   

13.
Myostatin, a new member of the TGF-p superfamily, is predominantly expressed in skeletal muscle cells and functions as a negative regulator of skeletal muscle growth in animals. Recently, we have reported three single nucleotide polymorphisms (SNPs) in the chicken my-ostatin gene. Herein, we investigate the association of those SNPs with the production traits in a F2 chicken line derived from Broilers crossing to Silky with the least square analysis. The results show that the BB and AA genotypes are strongly associated with abdominal fat weight (AFW), abdominal fat percentage (AFP), and birth weight (BW) (P < 0.05). Breast muscle percentage (BMP) of the AA type is higher than that of the AB type. The breast muscle weight and breast muscle percentages of F2 individuals have significant difference between CC and DD genotypes (P< 0.05). Breast muscle weight (BMW) of EF birds is higher than that of EE birds (P< 0.05). In this report, we present the first genetic evidence to show that chicken myostatin not o  相似文献   

14.
Six species and one subspecies of Chinese Platycorynus Chevr. are here describedas new. All the type specimens of new species are deposited in the Institute of Zoology,Academia Sinica, those of the new subspecies are deposited in the Kunming Institute ofZoology, Academia Sinica.  相似文献   

15.
16.
Salinity inhibits leaf growth in association with changes in cell size. The objective of this study was to determine the spatial distributions of the composition, number and dimensions of epidermal cells in the mature blades of leaf four of wheat seedlings under saline conditions. Plants were grown in loamy soil either with or without 120 mmol/L NaCl in a growth chamber, and harvested after leaf four was fully developed. The results of the spatial distribution analyses of width along the blade showed that salinity not only reduced the width of the leaf blade, but that it also altered the distribution pattern of blade width along the leaf axis. The reduction in the final size of the leaf blade was associated with a reduction in the total number of epidermal cells and in their widths and lengths. This study also revealed the spatial effects of salinity on the blade and epidermal cell dimensions along the leaf axis. In particular, salinity inhibited the total cell number for interstomatal, sister and elongated cells, implying that cell division in wheat leaves is inhibited by salinity. However, the lengths of interstomatal cells were not affected by salinity (unlike those for the sister and elongated cells), suggesting the relative contributions of cell length and numbers to the reduction in the final length of the blade under salinity is dependent on cell type.  相似文献   

17.
Breast cancer is the second most common type of cancer and the leading cause of cancer death in women worldwide. Adjuvant tamoxifen therapy significantly slows down estrogen receptor (ER)-positive breast cancer progression, prolongs diseasefree survival, and contributes to the decrease in breast cancer mortality (Musgrove and Sutherland, 2009). However, majority of the death from breast cancer is due to metastasis that is resistant to therapy (Musgrove and Sutherland, 2009).  相似文献   

18.
The family Sciaridae of Guizhou Province contains 10 genera and 57 species, ofwhich 1 genus and 43 species are new to science. The new taxa are described in taxonomickeys. The type specimens are kept in the Insect Collection of Beijing Agricultural Univer-sity. The letters given here are locality abbreviations used in the genus and specics listthat follows.  相似文献   

19.
By radioreceptor binding studies with iodinated TGF-β1,it has been shown that an undifferentiated ES-5 cell expresses approximately 3270 receptors with a dissociation constant Kd-130pM,but after the induction of differentiation by retinoic acid and dBcAMP,the receptor number of a differentiated RA-ES-5 cell was increased about 80% and the Kd was also increased to 370 pM.Furthermore,more direct evidence supporting the expression of TGF-β type I and type Ⅱ receptors in both ES-5 and RA-ES-5 cells has come from dot blot hybridization of cellular mRNA with cDNA probes for type I and type Ⅱ receptors.Meanwhile,mRNA expression level of types I and Ⅱ receptors in R-ES-5 cells were higher than that in ES-5 cells.Down-regulation of TGF-β receptors with a significant decrease in the rate of cell proliferation in both cells,was found by employing a pretreatment with neutralizing antibody to TGF-β1.The possible role of receptors for TGF-β in cell differentiation is discussed here.  相似文献   

20.
Hynobius amjiensis is a critically endangered salamander species(IUCN Red List) endemic to eastern China. It currently has three known populations: one in Longwangshan, Zhejiang Province(type locality), and two in Qingliangfeng between Anhui and Zhejiang Provinces. We examined the relatively unstudied breeding ecology of this species in the field and at laboratory from March 2007 to May 2014. Adult males and females were year-round terrestrial, except for the February–April breeding season. During this period, we captured only a total of 16 breeding adults(11 males and 5 females). As few as 100 breeding females were estimated based on the number of egg sacs observed since 2007. This number was significantly reduced from the estimated number between 1992 and 1998. Males(mean total length = 16.21 cm, mean body mass = 18.8 g) were slightly smaller than females(16.51 cm, 19.2 g). Size of breeding pools ranged from 0.2 m~2 to 1.2 m~2(0.1–1.2 m depths). Each female deposits a pair of egg sacs by attaching the adhesive tips of the sacs to aquatic plants or dead twigs. Fifteen pairs of egg sacs had an average length of 28.6 cm and a diameter of 3.3 cm. On average, each egg sac contained 75 eggs with a diameter of 0.3 cm. Our field survey revealed that H. amjiensis used oviposition sites in small, cool, and weakly acidic pools at high elevations(1 300–1 600 m) where peat moss was abundant. Reduction in wetland size and disappearance of suitable breeding pools suggest that this salamander species is under threat of extinction, particularly at Longwangshan, where 5 of the 9 breeding pools have either dried up or disappeared. Combined size of the remaining 4 pools is less than 2 m~2. We urge immediate implementation of more effective conservation measures and suggest that preservation priority should be given to habitat that contains suitable breeding pools.  相似文献   

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