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71.
In northern Shiraz (SW Iran), Lower Cretaceous carbonate was studied in detail. In this study, nine species of dasycladacea algae were classified. There are different species of dasycladacea algae which belong to seven different genera: Actinoporella, Cylindroporella, Dissocladela, Heteroporella, Neomeris, Salpingoporella, Trinocladus; one species of udoteaceae belongs to Bouenia; one species of acetabulariaceae belongs to Clypeina and the microproblematicum Coptocampylodon was also seen. Among the green algae, dasycladaceae and acetabulariceae are the most frequent and udoteaceans are rare in Zagros Mountains. The genus of Trinocladus is a new record for Lower Cretaceous (Upper Albian) in SW Iran.  相似文献   
72.
Abstract: In the early Late Devonian, terminal Frasnian proetid trilobites have previously only been known from Europe and North Africa. For the first time, a rich fauna of late Frasnian proetids is described from the Virgin Hills Formation, Canning Basin, Western Australia. Seventeen species in six genera are described, of which three are new: Rudybole gen. nov., Palpebralina gen. nov. and Canningbole gen. nov. A new subgenus, Chlupaciparia (Australoparia) subgen. nov. is also described. Fourteen of the species are new: Palpebralia initialis sp. nov., P. pustulata sp. nov., ?P. sp. nov. A, Rudybole depressa sp. nov., Palpebralina pseudopalpebralis sp. nov. (comprising the subspecies P. pseudopalpebralis pseudopalpebralis subsp. nov. and P. pseudopalpebralis ultima subsp. nov.), P. minor sp. nov., P. ocellifer sp. nov., Canningbole latimargo sp. nov., C. henwoodorum sp. nov., C. macromma sp. nov., Pteroparia extrema sp. nov., Chlupaciparia (Chlupaciparia) planiops sp. nov., Chlupaciparia (Australoparia) australis sp. nov. and C. (Australoparia) lata sp. nov. The subspecies Rudybole adorfensis angusta subsp. nov. is also described. The proetids range through conodont Zones 11–13b and terminate at the Upper Kellwasser Event, which marks the terminal Frasnian mass extinction event. Three of the six proetid lineages, Palpebralia, Canningbole and Pteroparia, show evolutionary trends of eye reduction. Two of the remaining lineages, Rudybole and Palpebralina, consist exclusively of blind taxa. The last, Chlupaciparia, also comprises forms with reduced eyes. The proetids show a stepped pattern of extinction during the late Frasnian, which correlate with two Kellwasser biocrises documented in European/North African Frasnian sections. The highest diversity preceded the Lower Kellwasser event that occurred at the end of conodont Zone 12 and saw the extinction of all species present in that zone. However, only one genus, Pteroparia, locally became extinct. A major higher‐level taxonomic mass extinction at the top of Zone 13b initiated the Upper Kellwasser extinction event. This included extinction at the generic level, with all five remaining genera becoming extinct, and at the family level, with the loss of the Tropidocoryphidae.  相似文献   
73.
【摘 要】目的 了解本地区儿童呼吸道感染病原菌种类、分布特点及其耐药性,为临床合理应用抗菌药物提供参考。方法 对2009年5月至2012年5月间本地区两家医院儿科住院患者送检的共1350份呼吸道分泌物的细菌培养结果及要检出菌的耐药情况,进行回顾性分析。结果 从1350份标本中共分离出384株病原菌,检出率为28.4%,革兰阴性杆菌258株,占67.2%,革兰阳性球菌95株,占24.7%,厌氧菌17株,占4.4%,真菌14株,占3.6%;革兰阴性前三位杆菌肺炎克雷伯杆菌、大肠埃希菌和解鸟氨酸克雷白杆菌对氨苄西林、哌拉西林耐药率均大于50%以上,共分离出产ESBLs菌57株,阳性率为43.2%;革兰阳性前三位球菌肺炎球菌、金黄色葡萄球菌和表皮葡萄球菌对青霉素、红霉素耐药率达50%以上。结论 本地区儿童呼吸道感染主要病原菌是革兰阴性杆菌,加强细菌培养和耐药性监测对临床合理使用抗生素有重要意义。  相似文献   
74.
目的了解小儿下呼吸道感染病原菌的分布及对常用抗菌药物的耐药状况。方法对2710例小儿下呼吸道感染患者痰标本进行培养,用VITEK-2Compact微生物鉴定系统鉴定菌种和药敏试验,WHO-NET5.4软件对数据进行分析。结果共分离病原菌675株,革兰阴性杆菌457株,占67.7%,主要为大肠埃希菌、肺炎克雷伯菌;革兰阳性球菌159株,占23.5%,主要为金黄色葡萄球菌、肺炎链球菌;真菌59株,占8.7%,主要为白色假丝酵母菌。结论小儿下呼吸道感染病原菌以革兰阴性杆菌为主,耐药性较为严重,应不断加强耐药性监测,合理使用抗菌药物。  相似文献   
75.
目的:探讨320排螺旋CT血管成像(CTA)在行双下肢动脉血管成像过程中,护理配合对的图像质量的影响。方法:将138例患者分为护理组(82例)及对照组(56例),分别进行320排螺旋CT双下肢血管造影检查,经高压团注造影剂欧乃派克,进行三维重组,获取容积再观(VR)、曲面重组(CPR)和最大密度投影(MIP)图像。对照组的患者只进行口头的训练,没有其他的护理干预措施;实验组进行一系列的护理干预以提高患者的配合,减低在成像过程中的非生理性运动。用工作站进行图像后处理,显示双下肢动脉图像,对其图像质量和影响因素进行分析,并在检查过程中的护理干预加以总结。结果:对照组有2例患者穿刺部位不合理而影响图像质量,对双下肢的病变显示具有一定的影响,3例患者注射压力过高引起外渗,流速在2.5-3.5 ml/s,影响了图像的清晰度,其余均获得满意效果。结论:良好的护理配合有利于320排CT双下肢成像的顺利进行,精心的护理操作是取得检查成功的动脉成像保证。  相似文献   
76.
Background: Hybridisation in Senecio/Jacobaea is frequent and of significance in speciation and evolution. Moreover, these genera are model systems for studying the evolution of pyrrolizidine alkaloids (PAs). Hybrids between Jacobaea aquatica and J. vulgaris have been reported from north-western Europe.

Aims: Our aim was to determine whether hybrids between Jacobaea aquatica and J. vulgaris also occurred in Austria, and if these hybrids could be responsible for the presumed increase of J. aquatica-like plants in this part of Europe. Furthermore, we tested if such hybrids showed an altered PA spectrum compared with parental species.

Methods: We used amplified fragment length polymorphisms (AFLPs) to analyse genetic diversity and structure, and gas chromatography–mass spectrometry (GC–MS) to identify PAs.

Results: We were able to identify genetically one hybrid population adjacent to a large J. aquatica population. The AFLP phenotypes of hybrids demonstrated a closer relationship to J. aquatica, suggesting frequent backcrossing. All hybrid individuals contained the same set of PAs as the parental species, but in differing amounts, plus four additional PAs, one of which may be novel.

Conclusions: Although hybridisation in Jacobaea is common, we were able to confirm only one hybrid population in Austria. Therefore, it seems unlikely that hybridisation plays a role in the presumed increase of J. aquatica in this area.  相似文献   
77.
The purpose of this study was to characterize responses in oxygen uptake ( V·O2), heart rate (HR), perceived exertion (OMNI scale) and integrated electromyogram (iEMG) readings during incremental Nordic walking (NW) and level walking (LW) on a treadmill. Ten healthy adults (four men, six women), who regularly engaged in physical activity in their daily lives, were enrolled in the study. All subjects were familiar with NW. Each subject began walking at 60 m/min for 3 minutes, with incremental increases of 10 m/min every 2 minutes up to 120 m/min V·O2 , V·E and HR were measured every 30 seconds, and the OMNI scale was used during the final 15 seconds of each exercise. EMG readings were recorded from the triceps brachii, vastus lateralis, biceps femoris, gastrocnemius, and tibialis anterior muscles. V·O2 was significantly higher during NW than during LW, with the exception of the speed of 70 m/min (P < 0.01). V·E and HR were higher during NW than LW at all walking speeds (P < 0.05 to 0.001). OMNI scale of the upper extremities was significantly higher during NW than during LW at all speeds (P < 0.05). Furthermore, the iEMG reading for the VL was lower during NW than during LW at all walking speeds, while the iEMG reading for the BF and GA muscles were significantly lower during NW than LW at some speeds. These data suggest that the use of poles in NW attenuates muscle activity in the lower extremities during the stance and push-off phases, and decreases that of the lower extremities and increase energy expenditure of the upper body and respiratory system at certain walking speeds.  相似文献   
78.
目的:探讨沙格雷酯治疗2型糖尿病伴下肢动脉硬化闭塞症(ASO)患者的临床疗效。方法:选择2014年4月~2015年5月我院2型糖尿病伴下肢ASO患者80例,给予口服沙格雷酯100 mg,3次/日,连续8周,监测治疗前后患肢的症状与体征、双下肢动脉峰值血流速度、血糖、血脂及血液流变学等指标的变化。结果:口服沙格雷酯8周后,患者疼痛感、冷感、间歇性踱行、麻木感及下肢溃疡等主观症状有效率均大于91%,临床总有效率为93.75%。治疗后患者左、右下肢动脉血管直径与治疗前比较,差异无统计学意义(P0.05),但左、右下肢动脉峰值血流速度比治疗前显著降低,差异有统计学意义(P0.05)。治疗后患者的甘油三酯、总胆固醇、低密度脂蛋白、全血高切黏度及全血低切黏度比治疗前降低,差异有统计学意义(P0.05)。结论:沙格雷酯可改善2型糖尿病伴下肢ASO患者的症状,降低双下肢动脉峰值血流速度,临床疗效确切,值得临床推广应用。  相似文献   
79.
目的:探讨导管接触性溶栓(catheter-directed thrombolysis,CDT)联合球囊及支架成形术治疗下肢动脉硬化闭塞症合并血栓形成的临床疗效及安全性。方法:选择2011年1月~2014年12月收治的36例下肢动脉硬化闭塞症合并血栓形成性病变患者,先行置管溶栓治疗,再联合球囊及支架成形术治疗,观察其溶栓效果及血管再通情况。结果:本组溶栓总有效率为86.1%,尿激酶用量(75.5±34.6)万单位,溶栓后31例下肢缺血症状改善,下肢疼痛症状有不同程度减轻,下肢跛行距离明显延长,无垃圾脚发生。球囊及支架成形术后踝肱指数(ABI)由术前的0.39±0.11升高至术后的0.79±0.19,差异有统计学意义(P0.01)。随访1~48月,无死亡病例,9例出现支架内膜增生血管再狭窄,5例出现糖尿病膝下动脉狭窄闭塞,给予球囊扩张及支架成形术后下肢缺血症状减轻,其中1例患者于术后3年行下肢截肢治疗。结论:CDT联合球囊及支架成形术治疗下肢动脉硬化闭塞症合并血栓形成具有较高的临床价值,可以为PTA血管成形或支架置入赢得时机,改善下肢缺血,该方式创伤小,并发症少。  相似文献   
80.
《L'Anthropologie》2016,120(3):237-262
The Lower Palaeolithic site of Menez-Dregan I is currently the subject of an important excavation and has been part of a multidisciplinary project since 1991. It is an ancient marine cave whose roof has gradually collapsed and thus partly protected the site from erosion. In Menez-Dregan 1, the sedimentological evidence has been significantly reduced due to multiple episodes of marine erosion in the cave (low sedimentary preservation in terms of sedimentation and erosion process). However, the proximity of a section with a longer sedimentary record (Gwendrez cliff) has allowed for an attempt at correlation between the different deposits by way of a sedimentologic study applied to sandy marker beds (dunes). The resulting new data permitted a more precise chronostratigraphy of this site to be drawn up and contributed to further validation of dating. Three main stratigraphic units show distinct levels of human occupation at the site, separated by coastal deposits. The ESR dates tend to place the first human occupation in MIS 12 or at the end of MIS 13 (around 465,000 years). The ESR dating obtained at the base of layer 5 gave an age of 380,000 years. The geological analysis (sedimentology, stratigraphical correlations at short distance) tends to confirm these dates. The fauna has not preserved due to the acidic environment, leaving only the lithic industry to show how the human groups who settled at the site lived and, it is worth noting, mastered fire lighting, and or control, at a very early date (late MIS 13 or early MIS 12). The lithic industry from the upper levels (layer 5) is likely Colombanian and is composed of numerous flakes and cores alongside a great quantity of cobble tools (mostly choppers), fractured cobbles, and cobbles with isolated removals on various types of rocks, some cleavers and very rare bifaces. Additionally denticulates and notches form the main part of the light duty tools, together with scrapers. These retouched light duty tools are mainly made on flint, but quartz and glossy sandstone were also used. The last level of occupation (layer 4) probably shows the transition between Lower and Middle Palaeolithic. This may represent a regional cobble tool industry of the south armorican shoreline, however, it is still difficult to separate it totally from the classic European Acheulean from Northern France. These armorican lithic industries could indeed correspond with areas of specialised activities, as demonstrated for some Middle Palaeolithic groups with a cobble tools lithic industry. The notion of culture that could be chosen to explain this variability must be treated with caution, because it would only be based on the presence or absence of only one type of tool (the handaxe).  相似文献   
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