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1.
Southwest Asia is a key region in current debates surrounding the appearance of the first cultures attributed to anatomically modern humans, particularly the Aurignacian and preceding cultural units of the Iranian Zagros, Levant, and the Balkans (Baradostian, Ahmarien, Kozarnikien, etc.). The Zagros mountain range encompasses an immense territory that remains understudied with regard to the Upper Paleolithic as well as the first bladelet industries traditionally presumed to be the work of anatomically modern humans. Concerning the emergence of the Aurignacian, the sites of Warwasi rockshelter and Yafteh cave in the central Zagros are considered to show evidence of in situ evolution of the Upper Paleolithic from the local Mousterian. This hypothesis is tested by way of a taphonomic, techno-typological and economic approach applied to the Upper Paleolithic levels of Warwasi (spits LL–AA) and Yafteh (the series from the lower part of the sequence). A comparison of the techno-economic features of both assemblages demonstrates a conceptual bond with contemporaneous techno-complexes from Levant and Europe (Ahmarian, Protoaurignacian, etc.). The techno-typological Middle Paleolithic character of the Warwasi lithic assemblage permits a discussion of a possible in situ dependence/continuum from the Mousterian or perhaps particular activities linked to the type of the occupation of the site. However, bladelet technology cannot be considered as rooted in the Zagros Mousterian. Consequently the origin of the Aurignacian sensu stricto has to be reconsidered.  相似文献   

2.
The World Health Organization(WHO)estimatesthat as manyas80%of the world′s populationrely pri-marily on plant and animal-based medicines.Amongthe252essential chemicals that have been selected bythe World Health Organization,11.1%comefrompla-nts,and8.7%fr…  相似文献   

3.
This article analyses high-quality hydroclimate proxy records and spatial reconstructions from the Central and Eastern Mediterranean and compares them with two Earth System Model simulations (CCSM4, MPI-ESM-P) for the Crusader period in the Levant (1095–1290 CE), the Mamluk regime in Transjordan (1260–1516 CE) and the Ottoman crisis and Celâlî Rebellion (1580–1610 CE). During the three time intervals, environmental and climatic stress tested the resilience of complex societies. We find that the multidecadal precipitation and drought variations in the Central and Eastern Mediterranean cannot be explained by external forcings (solar variations, tropical volcanism); rather they were driven by internal climate dynamics. Our research emphasises the challenges, opportunities and limitations of linking proxy records, palaeoreconstructions and model simulations to better understand how climate can affect human history.  相似文献   

4.
Transient receptor potential vanilloid type channels (TRPVs) are expressed in several cell types in human and animal lungs. Increasing evidence has demonstrated important roles of these cation channels, particularly TRPV1 and TRPV4, in the regulation of airway function. These TRPVs can be activated by a number of endogenous substances (hydrogen ion, certain lipoxygenase products, etc.) and changes in physiological conditions (e.g., temperature, osmolarity, etc.). Activation of these channels can evoke Ca(2+) influx and excitation of the neuron. TRPV1 channels are generally expressed in non-myelinated afferents innervating the airways and lungs, which also contain sensory neuropeptides such as tachykinins. Upon stimulation, these sensory nerves elicit centrally-mediated reflex responses as well as local release of tachykinins, and result in cough, airway irritation, reflex bronchoconstriction and neurogenic inflammation in the airways. Recent studies clearly demonstrated that the excitability of TRPV1 channels is up-regulated by certain autacoids (e.g., prostaglandin E(2), bradykinin) released during airway inflammatory reaction. Under these conditions, the TRPV1 can be activated by a slight increase in airway temperature or tissue acidity. Indirect evidence also suggests that TRPV channels may play a part in the pathogenesis of certain respiratory diseases such as asthma and chronic cough. Therefore, the potential use of TRPV antagonists as a novel therapy for these diseases certainly merits further investigation.  相似文献   

5.
The population history of the East Slavs is complicated. There are still many unanswered questions relating to the origins and formation of the East Slavic gene pool. The aims of the current study were as follows: (1) to assess the degree of biological affinity in medieval East Slavic tribes and to test the hypothesis that East Slavic peoples have a common origin; (2) to show their genetic connections to the autochthonous populations of the northern part of Eastern Europe (Baltic and Finno‐Ugric tribes); and (3) to identify a genetic continuity between the bearers of Chernyakhov culture and medieval Eastern Slavs. In this study, nonmetric cranial trait data for medieval East Slavic tribes and comparative samples from unrelated groups were examined. Analyzes of phenotypic differentiation were based on Nei's standard genetic distance and hierarchical GST statistics. The results obtained suggest that the genetic affinity of the East Slavic tribes is due not only to inter‐tribal gene flow, but is, more importantly, a result of their common population history. Evidence of gene flow from the Baltic and Finno‐Ugric groups was showed in the gene pool of Eastern Slavs, as was genetic continuity between medieval East Slavic tribes and the populations of the preceding Chernyakhov culture. These findings support a “generalizing” hypothesis of East Slavic origin, in which a Slavic community was formed in some particular ancestral area, and subsequently spread throughout Eastern Europe. Am J Phys Anthropol 152:495–505, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

6.
通过对我国学者近2年在国内外发表的相关论文进行检索和整理,分类综述针对神经退行性疾病(如阿尔茨海默病、帕金森病等)、心血管疾病(如高血压、心律失常、心衰、冠心病、心肌梗死、动脉粥样硬化等)、脑血管疾病、代谢类疾病(如肥胖症、血脂异常、脂肪肝、糖尿病等)、感染性疾病(如艾滋病、流感、结核病等)、恶性肿瘤、自身免疫性疾病等多种疾病的药物作用靶点研究最新进展。  相似文献   

7.
大气氟污染源附近食桑昆虫中氟的积累和分布   总被引:1,自引:0,他引:1  
对大气F污染源附近野桑蚕,桑赤蠖和桑蚕体内的氟化物含量和器官分布进行了研究,结果表明,污染源附近食桑昆虫体有较高的氟化物含量,且食桑昆虫体的氟化物含量随着离污染源的距离增大而降低,野桑蚕,桑赤蠖和桑蚕的氟化物含量与桑叶的氟化物含量有极显著的线性正相关性,食桑昆虫不同器官间的氟化物积累量也存在较大差异,其消化管是食桑昆虫的主要氟化物积累器官。  相似文献   

8.
9.
Scorpion and its organs have been used to cure epilepsy, rheumatism, and male impotency since medieval times. Scorpion venom which contains different compounds like enzyme and non-enzyme proteins, ions, free amino acids, and other organic inorganic substances have been reported to posses antiproliferative, cytotoxic, apoptogenic, and immunosuppressive properties. We for the first time report the apoptotic and antiproliferative effects of scorpion venom (Odontobuthus doriae) in human neuroblastoma cells. After exposure of cells to medium containing varying concentrations of venom (10, 25, 50, 100, and 200 μg/ml), cell viability decreased to 90.75, 75.53, 55.52, 37.85, and 14.30%, respectively, after 24 h. Cells expressed morphological changes like swelling, inhibition of neurite outgrowth, irregular shape, aggregation, rupture of membrane, and release of cytosolic contents after treatment with venom. Lactate dehydrogenase (LDH) level increased in 50 and 100 μg/ml as compared to control, but there was no significant increase in LDH level at a dose of 10 and 20 μg/ml. Two concentrations viz. 50 and 100 μ/ml were selected because of the profound effect of these concentrations on the cellular health and population. Treatment with these two concentrations induced reactive nitrogen intermediates and depolarization in mitochondria. While caspase-3 activity increased in a concentration-dependent manner, only 50 μg/ml was able to fragment DNA. It was interesting to note that at higher dose, i.e., 100 μg/ml, the cells were killed, supposedly by acute necrosis. DNA synthesis evidenced by bromodeoxyuridine (BrdU) incorporation was inhibited in a concentration-dependent manner. The cells without treatment incorporated BrdU with high affinity confirming their cancerous nature whereas very less incorporation was noticed in treated cells. Our results show apoptotic and antiproliferative potential of scorpion venom (O. doriae) in human neuroblastoma cells. These properties make scorpion venom a valuable therapeutic agent in cancer research.  相似文献   

10.
燕麦属(Avena L.)植物中有5个栽培种即普通栽培燕麦(A. sativa L.)、埃塞俄比亚燕麦(A. abyssinica Hochst.)、地中海燕麦(A. byzantina Koch)、砂燕麦(A. strigosa Schreb.)和大粒裸燕麦又称莜麦(A. nuda L.),其中大粒裸燕麦的子粒不带稃皮为裸燕麦,其他物种均带稃皮为皮燕麦。国际上主要种植皮燕麦,而我国主要种植大粒裸燕麦,由此不难看出,大粒裸燕麦在世界燕麦中占有特殊的地位。然而,关于大粒裸燕麦的起源和分类地位问题,迄今学者们的意见仍不尽相同。笔者通过参阅有关文献和研究实践,对这两个问题进行探讨,认为大粒裸燕麦起源于我国山西和内蒙古一带,在植物学分类上应为一个独立的物种即A. nuda L.。  相似文献   

11.
The term "functional foods" comprises some bacterial strains and products of plant and animal origin containing physiologically active compounds beneficial for human health and reducing the risk of chronic diseases. Among the best known functional compounds probiotics, prebiotics and natural antioxidants should be given as examples. These substances can be obtained by biotechnological methods and by extraction from plant or animal tissues.  相似文献   

12.
Non-siliceous algae in a five meter core from Lake Kinneret (Israel)   总被引:1,自引:1,他引:0  
U. Pollingher 《Hydrobiologia》1986,143(1):213-216
The composition and succession of non-siliceous algae, studied in a five meter core from Lake Kinneret (Israel), are described. Only Chlorophyta species were recorded, probably due to the standard palynological sample processing which was used. In the lower part of the core, from the bottom to 300 cm (interval 5500–2500 years B.P.), Botryococcus braunii was the only common alga. Relevant changes in algal diversity and abundance occur at 300 cm. Many species of green algae were recorded for the first time (Pediastrum, Scenedesmus, Coelastrum, etc.). These changes may be related to an increase in nutrient concentration as a consequence of cultural disturbance. In the interval 300-0 cm, a succession of Pediastrum species is followed. The recovered green algae are extant in the present plankton of Lake Kinneret. They also constitute an important part of the algae found in the profundal sediments today.  相似文献   

13.
With steam navigation, men, but also seeds of diseases, move faster. In 1865, the pilgrimage to Mecca induced a terrible cholera pandemic. This caused deep trauma in Europe and prompted the international community, recently born, to focus on the pilgrims who were regarded as the main "risk group" in the spread of epidemics. Through a series of international sanitary conferences, European powers, in agreement with the Ottoman Empire, imposed a heavy control over the pilgrims, much harsher than that applied to ordinary commercial navigation exchanges. These decisions led to the establishment of a huge quarantine device in the Red Sea and the Levant, including two lazaretto, one at the entrance and the other at the exit of the Red Sea, where the pilgrims were trapped and disinfected during their sacred journey. This contrasted with the concommitant disappearance of quarantines everywhere else. The pilgrims did not show hostility towards medical and prophylactic treatments but protested against the dehumanizing conditions of their realization. The combined pressures of nationalism and sovereignty claims from Saudi Arabia ended this system in 1957.  相似文献   

14.
Abstract: Silkworm ( Bombyx mori L.) is one of the important economic insects. Silkworm rearing and silk industry plays an important role in China, India and other developing countries. In the long history of sericultural practice, introduction of silkworm strains with high resistance to diseases has greatly improved cocoon and silk quality and productivity. However, current silkworm breeding is mainly based on traditional method that involves high input of time and labour. In order to increase the selection efficiency and accuracy for future silkworm breeding, it is necessary to establish a molecular marker-assisted selection system. In our study, three silkworm near isogenic lines that had different resistance to nuclear polyhedrosis virus (NPV) were established by means of different hybridization methods. A total of 150 random amplified polymorphic DNA (RAPD) random primers were used to screen molecular markers. Among them, two molecular markers OPA-18700 and OPY-11400 were found linked to major genes resistant and susceptible to NPV, respectively. Validity of the molecular markers was proved in F2 populations.  相似文献   

15.
A new method for the determination of the antilactoferrin activity (ALfA) of microorganisms, based on the detection of lactoferrin by the enzyme immunoassay, is proposed. The new method widens the spectrum of microorganisms to be tested, makes it possible to detect lactoferrin inactivation by bacteria producing antagonistically active substances (muramidases, organic acids, hydrogen peroxide, etc.), increases the reliability of the determination of the ALfA antilactoferrin activity of microorganisms due to the increased accuracy of its quantitative characterization. Testing of the culture fluid for lactoferrin following the growth of microorganisms in a medium with this protein revealed the capacity to inactivate lactoferrin in bacteria (Escherichia coli, Salmonella sp.) and yeast-like fungi (Candida sp.), isolated from feces and clinical material, of persons with carrier states, dysbiotic disturbances and pyoinflammatory diseases.  相似文献   

16.
The incidence of spina bifida in the Community of Madrid (Spain) has been assessed during an eleven-year period, since 1970 to 1980: 0.37 per 1,000 newborns over a total of 272,332 newborns, dead and alive, of simple births. The sex ratio at birth was 94. Maternal variables have been studied (maternal age, menarche, parity, etc.), obstetric variables (number of abortions, medication during pregnancy, etc.) and also neonatal variables (weight, gestational age, state at birth, etc.). Seasonal variations were observed.  相似文献   

17.
A review of history of genosystematics (macromolecular systematics) from E. Chargaff and A. N. Belozersky up to date. The role of A.N. Belozersky and his collaborators in the development of this new branch of systematics is analyzed. Genosystematics was the source of valuable information clarifying some aspects of biological evolution. Its methods were successfully employed in microorganisms--(e.g., discovery of archaebacteria) and in eucaryote systematics (origin of plastids, falcification of "molecular clock" hypothesis, substantial changes in higher plants phylogenetics, etc.). However, attempts to employ some fragmentary and unreliable data obtained by genosystematics for modifying the existing phylogenetic schemes and systems of organisms failed. Nowadays genosystematics is like a newborn child suffering from children's diseases well-known to "classical" systematics. It is rather far from final conclusions describing the evolution of genotypes. Some of its recent achievments, e.g., elaboration of the concept of PhyloCode, allow to believe that this science is able to suggest revolutionary changes in Linnean systematics.  相似文献   

18.
Millions of biological samples, including cells of human, animal or bacterial origin, viruses, serum/plasma or DNA/RNA, are stored every year throughout the world for diagnostics and research. The purpose of this review is to summarize the resources necessary to set up a bio-banking facility, the challenges and pitfalls of sample collection, and the most important techniques for separation and storage of samples. Biological samples can be stored for up to 30 years, but specific protocols are required to reduce the damage induced by preservation techniques. Software dedicated to biological banks facilitate sample registration and identification, the cataloguing of sample properties (type of sample/specimen, associated diseases and/or therapeutic protocols, environmental information, etc.), sample tracking, quality assurance and specimen availability. Bio-bank facilities must adopt good laboratory practices and a stringent quality control system and, when required, comply with ethical issues.  相似文献   

19.
Hepatocyte transplantation is considered as an alternative to organ transplantation in particular for the treatment of liver metabolic diseases. However, due to the difficulties to obtain a large number of hepatocytes, new sources of cells are needed. These cells could be either of hepatic origin (hepatic stem cells) or extrahepatic such as mesenchymal stem cells or pluripotent stem cells (human embryonic stem cells [hESC] or iPS). We developed a new method to differentiate hESCs into fetal hepatocytes. These conditions recapitulate the main liver developmental stages, using fully defined medium devoid of animal products or unknown factors. The differentiated cells express many fetal hepatocytes markers (cytochrome P450 3A7, albumin, alpha-1-antitrypsin, etc.). The cells display specific hepatic functions (ammonia metabolism, excretion of indocyanin green) and are capable to engraft and express hepatic proteins two months after transplantation into newborn uPAxrag2gc-/- mouse liver. We have also showed that this approach is transposable to human iPS, and further studies on animal models will allow us to compare the in vivo potential of these two sources of pluripotent cells. Finally, only studies on large animals such as nonhuman primates will validate an eventual clinical application.  相似文献   

20.
The history of use by the man of plants of a sort Cannabis totals more than 4000 years. The people have begun to use Cannabis in stone century. On Taiwan archaeologist the rests of utensils made with application of stalks Cannabis more of 10000 years back were found. Cannabis (Cannabis sativa, Cannabis sowing, named also "Indian") - cultural plant, which has set of applications. From it received fibres for hemp of ropes and make a fabric similar on linen. Its stalks went on manufacture glossy of a paper and building of plates. Her sabadilla were used for graziery a bird; oil from sabadilla Cannabis offered as fuel instead of diesel. The greatest popularity Cannabis has received as raw material for reception of products (marijuana, hashish etc.), causing at the man psychotropic--first of all psychomymetic--effects, that at their regular application can result in formation of dependence. Besides the attempts were undertaken to use preparations Cannabis in the medical purposes: at migraine, spasmes, vomiting, pains of a different origin etc.  相似文献   

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