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1.
《Plains anthropologist》2013,58(67):1-25
Abstract

The Stricker site is a multi-component habitation area in Big Bend Reservoir, South Dakota. Component A, the latest and most I imited occupation, represents the Dakota from the middle of the 19th century to the present. Component B represents the major occupation by people following the Coalescent Tradition in the form of the Extended Coalescent variant. Component C, a minor occupation, is representative of the Initial variant of the Middle Missouri Tradition. Most of the features and artifacts pertain to Component B. The analysis provides evidence for a transition from the Shannon phase into the Felicia phase  相似文献   

2.
Abstract

The Breeden Site cultural sequence reenforcesthe general culture history already established for the Bad-Cheyenne Region and the more inclusive Middle Missouri Tradition. House remains and the bulk of the ceramic materials from the site indicate habitation of the area by peoples of the Initial Middle Missouri Variant and the PostContact Coalescent Variant.Component A at the Breeden Site and the Monroe and Anderson components at the Dodd Site exhibit a complex of diagnosticcultural traits significant enough to define a new phase - the Anderson Phase. A temporal span of approximately A.D. 950to 1250 is suggested for the phase. Component B of the Breeden Site, an early manifestation of the Post-Contract Coalescent Variant, is closely associated with components of the Felicia Phase and the putative Talking Crow Phase. Breeden Component B probably represents an upriver movement of Coalescent peoples from the Big Bend area, eventually being assimilated into the Arikara populations of the Bad River Phase within the Bad-Cheyenne Region.  相似文献   

3.
The globin derived from the monomer Component IV hemoglobin of the marine annelid,Glycera dibranchiata, has been completely sequenced, and the resulting information has been used to create a structural model of the protein. The most important result is that the consensus sequence of Component IV differs by 3 amino acids from a cDNA-predicted amino acid sequence thought earlier to encode the Component IV hemoglobin. This work reveals that the histidine (E7), typical of most heme-containing globins, is replaced by leucine in Component IV. Also significant is that this sequence is not identical to any of the previously reportedGlycera dibranchiata monomer hemoglobin sequences, including the sequence from a previously reported crystal structure, but has high identity to all. A three-dimensional structual model for monomer Component IV hemoglobin was constructed using the published 1.5 å crystal structure of a monomer hemoglobin fromGlycera dibranchiata as a template. The model shows several interesting features: (1) a Phe31 (B10) that is positioned in the active site; (2) a His39 occurs in an interhelical region occupied by Pro in 98.2% of reported globin sequences; and (3) a Met41 is found at a position that emerges from this work as a previously unrecognized heme contact.  相似文献   

4.
5-Oxo-L-prolinase from Pseudomonas putida is composed of two reversibly dissociable proteins: Component A catalyzes 5-oxoproline-dependent cleavage of ATP, but does not catalyze the decyclization of 5-oxoproline; Component B is required for the coupling of ATP cleavage to ring-opening of 5-oxoproline to form glutamate (Seddon, A. P., Li, L., and Meister, A. (1984) J. Biol. Chem. 259, 8091-8094). We describe here the purifications of Components A and B to apparent homogeneity and the interactions between these two proteins. The cellular content of Component B activity is significantly greater than that of Component A. By gel filtration, Component A is a hexamer; but in the presence of substrates, it is a dimer. Component B can exist as an aggregate, an octamer, or a tetramer, depending upon the conditions used. Gel filtration of a mixture of Components A and B in the presence of substrates gives a unique protein species that exhibits 5-oxoprolinase activity. The Mr of this Component A-Component B complex indicates that it probably has an A2-B2 structure. The molar ratio of Component A to Component B in the complex was determined to be 1:1 by the continuous variation method (Job). Titrations of each component by the other suggest that phosphorylated 5-oxoproline-bound Component A is the entity that interacts with Component B. These studies indicate that the binding of phosphorylated 5-oxoproline-bound Component A to Component B to form a complex proceeds by a cooperative type mechanism. This is supported by the observed shifts of the intersection points of the Job curves (see Appendix).  相似文献   

5.
《Plains anthropologist》2013,58(22):231-237
Abstract

In the Plains periphery of the Central Area, Missouri, extensive preceramic remains are found. Well recognized complexe s with Paleo-Indian connections are Nebo Hill, Sedalia, Graham Cave Levels 6-4, andArnoldResearch Cave. Radiocarbon dates range from 7738 B. C. to 4322 B. C. Other preceramic complexes described from excavations include the Hatten Mound component and the Lincoln County burial site, in the Northwest Prairie; Blackwell Component A in the Ozark Highland; and the Jakie L2 and L3 components dated at 5112 B. C. to 4422 B. C. in the Southwest Drainage. Surface collections from all areas indicate preceramic occupations.  相似文献   

6.
Kinetics of dark recoveries of Component X, Center A, and Center B at 20 and 0 °C after a 30-s illumination were studied in membrane fragments from a blue-green alga by using low temperature electron paramagnetic resonance spectroscopy in combination with a quick-freeze method. These kinetics were compared with those obtained by spectrophotometry under the same conditions. Contrary to the currently popular view, the result strongly suggests that Component X, rather than Center A or Center B, is P430.  相似文献   

7.
The globin derived from the monomer Component IV hemoglobin of the marine annelid,Glycera dibranchiata, has been completely sequenced, and the resulting information has been used to create a structural model of the protein. The most important result is that the consensus sequence of Component IV differs by 3 amino acids from a cDNA-predicted amino acid sequence thought earlier to encode the Component IV hemoglobin. This work reveals that the histidine (E7), typical of most heme-containing globins, is replaced by leucine in Component IV. Also significant is that this sequence is not identical to any of the previously reportedGlycera dibranchiata monomer hemoglobin sequences, including the sequence from a previously reported crystal structure, but has high identity to all. A three-dimensional structual model for monomer Component IV hemoglobin was constructed using the published 1.5 å crystal structure of a monomer hemoglobin fromGlycera dibranchiata as a template. The model shows several interesting features: (1) a Phe31 (B10) that is positioned in the active site; (2) a His39 occurs in an interhelical region occupied by Pro in 98.2% of reported globin sequences; and (3) a Met41 is found at a position that emerges from this work as a previously unrecognized heme contact.Abbreviations used GMHX the holo-protein (including b-type heme, Glycera dibranchiata monomer hemoglobin Component X (X=2, 3, or 4) - GMGX the apo-protein, or globin, Glycera dibranchiata monomer globin derived from Component X (X=2, 3, or 4) - rec-gmg the globin derived from a recombinant holoprotein of a Glycera dibranchiata monomer hemoglobin, rec-gmh, whose sequence has been inferred from an isolated cDNA insert - CB label refers to peptides generated from cyanogen bromide cleavage of GMG4 - HPLC high-performance liquid chromatography - T label refers to peptides generated from trypsin digests of GMG4 - Mb myoglobin - MCS monomer hemoglobin crystal structure from Glycera dibranchiata. H, N-terminal sequence of GMG4 - SWMb sperm whale myoglobin  相似文献   

8.
目的:比较高浓度玻璃酸钠滴眼液与聚乙二醇滴眼液防治飞秒激光辅助LASIK术后干眼的临床效果。方法:选取2016年1月至2017年1月在我院视光学中心收治的飞秒激光辅助LASIK术后干眼患者80例并将其随机分为A、B两组,分别给予玻璃酸钠滴眼液(3 g/L)、聚乙二醇滴眼液,在用药后1周、2周、1个月进行干眼体征检查,比较患者用药前后泪液分泌试验(SIT)、泪膜破裂时间(BUT)、角膜荧光素染色(FL)的变化。结果:术后1周,所有患者BUT均较术前显著降低,FL均较术前显著升高,差异均有统计学意义(P0.05),但SIT与术前比较差异无统计学意义(P0.05)。两组患者用药后SIT数值随时间变化差异没有统计学意义(P0.05);A组和B组分别在用药后1周、2周、1个月时进行比较,SIT变化差异没有统计学意义(P0.05);而A组BUT时间、FL评分改善时间明显早于B组,差异有统计学意义(P0.05)。结论:滴用高浓度玻璃酸钠滴眼液(3 g/L)对飞秒激光辅助LASIK术后干眼患者的效果明显优于滴用聚乙二醇。  相似文献   

9.
《Journal of bryology》2013,35(4):745-751
Abstract

Contrary to an earlier report that the spore sac in Archidium is endothecial in origin, evidence is presented from this earlier report on A. alternifolium and from observations on A. stellatum that the spore sac is amphithecial in origin as in the Bryideae. The retention of Archidium in the Archidiidae is supported on sporophytic evidence.  相似文献   

10.
Abstract

The predictions of currently available theories for treating DNA-diffuse ionic cloud free energy contributions to conformational stability have been tested against experimental data for salt induced B-Z and B-A transitions. The theories considered are (i) Manning's counterion condensation approach (CC), (ii) the idealized Poisson-Boltzmann approximation (PB), and (iii) the potentials of mean force (PMF) approach proposed by Soumpasis. As far as we can judge from comparison with the set of experimental data currently available, it is found that only the latter theory yields satisfactory quantitative results for the dependence of the B-Z and B-A relative stabilities on monovalent salt concentration. The correct application of the PB and CC theories does not yield very low salt Z-B transitions, in contradiction to earlier assertions. At low salt concentrations the PB theory is qualitatively correct in predicting that the B form is electrostatically more favorable than both the A and B forms, whereas the CC theory is qualitatively wrong predicting that Z-DNA is more stable than both B and A DNA.  相似文献   

11.
《Gender Medicine》2005,2(4):246-254
Background:Effective self-care, including adherence to diet, exercise, and medication regimens, is an essential component of health care for individuals with diabetes mellitus (DM).Objective:The goals of this study were to examine sex-based differences in DM and to explore the effects of gender on self-care.Methods:This study was conducted retrospectively using data from the 2001 Medical Expenditure Panel Survey (MEPS). People with DM were identified by International Classification of Diseases, Ninth Revision, Clinical Modification diagnostic code; analyses were stratified by sex. Variables included age, race/ethnicity, education, income, body mass index (BMI), number of comorbidities, physical and cognitive limitations, smoking status, and depression. Outcome measures were assessed by Short Form-12 (SF-12) Mental Component Summary (MCS) and Physical Component Summary (PCS) scores. Univariate analyses were determined using t, χ2, or Fisher exact tests, as appropriate. Multivariate analyses examined associations between sex and SF-12 MCS/PCS scores adjusted for other variables.Results:A total of 1653 MEPS respondents (883 women, 770 men) with DM were identified for the current study. The women were significantly older than the men (61.2 vs 59.1 years), had less education (11.1 vs 12.0 years), and had lower incomes. Women had higher calculated BMI (31.4 vs 30.3), more comorbidities (7.8 vs 6.4), more depression, and more physical and cognitive limitations than did men. Women also scored lower than men on the SF-12 MCS and PCS (47.8 vs 49.9 and 38.2 vs 41.4, respectively). All these measures were statistically significant (P < 0.01). In multivariate analyses, physical limitations, BMI, and number of comorbidities were negatively correlated, and income and education were positively correlated, with MCS and PCS scores.Conclusions:Compared with their male counterparts, diabetic women scored lower on measuresof health status and functioning—factors that are likely to affect self-care activities. Sex-based differences should be considered when developing screening and treatment programs for people with DM.  相似文献   

12.
摘要 目的:观察腹腔镜胆囊切除术治疗胆囊结石合并急性胆囊炎的疗效及对免疫功能和生活质量的影响。方法:本次研究为回顾性研究,分析2018年3月~2021年3月期间我院收治的98例胆囊结石合并急性胆囊炎患者的临床资料,根据手术方案的不同将患者分为A组(n=46,给予开腹手术)和B组(n=52,给予腹腔镜胆囊切除术),记录两组患者围术期相关指标、肝功能、免疫功能、生活质量和并发症发生率。结果:B组术中出血量少于A组,切口大小短于A组,手术时间长于A组,住院时间、首次排气时间短于A组(P<0.05)。两组术后3 d总胆红素 (TBIL)、谷丙转氨酶(ALT)、谷草转氨酶(AST)均升高,但B组低于A组(P<0.05)。B组术后3 d CD3+、CD4+、NK细胞、CD4+/CD8+高于A组(P<0.05),B组术后3 d CD8+低于A组(P<0.05)。B组术后3个月健康生活量表简表(SF-36)各维度评分高于A组(P<0.05)。B组术后并发症发生率虽低于A组,但组间对比差异无统计学意义(P>0.05)。结论:腹腔镜胆囊切除术治疗胆囊结石合并急性胆囊炎,虽然手术时间较开腹手术更长,但切口小、可促进患者术后恢复,对患者免疫功能、肝功能损害更轻,有利于提高患者生活质量。  相似文献   

13.
Abstract

A multivariate data-representation of a portion of the 1H-NOESY spectrum of an RNA octamer duplex was used to explore the possibility of using Principal Component Analysis and Partial Least Squares Discrimination for pattern recognition. In this case, it is found that the methods can: (i) distinguish slices containing signal from those containing only noise, (ii) locate slices containing overlapping signals, and (iii) in some cases to segregate slices with unique aspects such as those from terminal nucleotides, overlapping signals, purine-H8, pyrimidine-H6 and adenine-H2 containing slices. These properties can easily be included in a scheme to automate spectral analysis. The formulation described here does not distinguish patterns needed to automate sequential assignment of resonances in NOESY spectra of RNA.  相似文献   

14.
Bacterial 5-oxoprolinase is composed of two protein components: Component A, which catalyzes 5-oxoproline-dependent ATP-hydrolysis and Component B, which couples the hydrolysis of ATP with the decyclization of 5-oxoproline to form glutamate (Seddon, A. P., Li, L., and Meister, A. (1984) J. Biol. Chem. 259, 8091-8094). Studies on this unusual enzyme system have led to evidence that an intermediate is formed by Component A. Application of the isotope-trapping method demonstrated an activated 5-oxoproline intermediate, whose formation requires ATP, Mg2+, and Component A. The amount of ATP-dependent trapping was close to the number of enzyme active sites. The intermediate formed by Component A was shown to be reducible by potassium borohydride to proline in low yield; when Component B was added, the formation of proline was abolished. Treatment of reaction mixtures containing Component A, 5-oxoproline, and [gamma-32P] ATP with diazomethane led to appearance of a 32P-labeled compound (found on thin layer chromatography), whose formation was significantly reduced when Component B was present. The new compound, which is labile, breaks down to form dimethyl[32P]phosphate. The total amount of dimethyl[32P]phosphate formed after breakdown is close to the number of active sites of Component A. The data are consistent with the conclusion that a phosphorylated form of 5-oxoproline is formed by Component A and suggest that Component B is required for conversion of this intermediate to glutamate.  相似文献   

15.
摘要 目的:探讨不同切口超声乳化术联合小梁切除术对白内障合并青光眼患者视力、角膜内皮细胞及生活质量的影响。方法:回顾性分析2018年4月~2019年7月期间我院收治的150例白内障合并青光眼患者的临床资料,根据手术方式的不同分为A组(n=75,单切口超声乳化术联合小梁切除术)和B组(n=75,双切口超声乳化术联合小梁切除术)。比较两组患者眼压、裸眼视力、最佳矫正视力、角膜内皮细胞、生活质量及并发症。结果:两组术后3个月健康调查简表(SF-36)各维度评分均升高,且B组高于A组(P<0.05)。两组术后3个月眼压均降低,且B组低于A组(P<0.05);两组术后3个月裸眼视力和最佳矫正视力均升高,且B组高于A组(P<0.05)。两组术后3个月角膜内皮细胞面积均增加,但B组小于A组(P<0.05);角膜内皮细胞密度均下降,但B组高于A组(P<0.05)。B组术后并发症总发生率低于A组(P<0.05)。结论:与单切口超声乳化术联合小梁切除术相比,白内障合并青光眼患者采用双切口超声乳化术联合小梁切除术治疗,在改善患者眼压、裸眼视力、最佳矫正视力、角膜内皮细胞、生活质量及减少并发症发生率方面的效果更佳。  相似文献   

16.
目的:对比颌骨囊肿经传统刮治术与开窗减压术治疗后的手术效果、生活质量和预后。方法:回顾性选取2016年1月~2018年7月期间我院收治的90例颌骨囊肿患者的临床资料,上述患者根据手术方式的不同分为A组(n=45,传统刮治术)和B组(n=45,开窗减压术),比较两组患者疗效、临床指标、生活质量和预后。结果:B组患者临床总有效率为97.78%(44/45),高于A组的84.44%(38/45)(P0.05)。B组患者伤口愈合时间、手术时间、均短于A组,术中出血量少于A组(P0.05)。两组患者末次随访时情绪、外貌、味觉、疼痛、唾液、咀嚼等项目评分均升高,且B组高于A组(P0.05)。B组并发症发生率、复发率均低于A组(P0.05)。结论:与传统刮治术治疗相比,开窗减压术治疗颌骨囊肿,在手术效果、生活质量和预后方面效果显著,具有较高的临床应用价值。  相似文献   

17.
《PloS one》2016,11(3)
IntroductionDetermining the optimal time to vaccinate is important for influenza vaccination programmes. Here, we assessed the temporal characteristics of influenza epidemics in the Northern and Southern hemispheres and in the tropics, and discuss their implications for vaccination programmes.MethodsThis was a retrospective analysis of surveillance data between 2000 and 2014 from the Global Influenza B Study database. The seasonal peak of influenza was defined as the week with the most reported cases (overall, A, and B) in the season. The duration of seasonal activity was assessed using the maximum proportion of influenza cases during three consecutive months and the minimum number of months with ≥80% of cases in the season. We also assessed whether co-circulation of A and B virus types affected the duration of influenza epidemics.Results212 influenza seasons and 571,907 cases were included from 30 countries. In tropical countries, the seasonal influenza activity lasted longer and the peaks of influenza A and B coincided less frequently than in temperate countries. Temporal characteristics of influenza epidemics were heterogeneous in the tropics, with distinct seasonal epidemics observed only in some countries. Seasons with co-circulation of influenza A and B were longer than influenza A seasons, especially in the tropics.DiscussionOur findings show that influenza seasonality is less well defined in the tropics than in temperate regions. This has important implications for vaccination programmes in these countries. High-quality influenza surveillance systems are needed in the tropics to enable decisions about when to vaccinate.  相似文献   

18.
目的:探讨CPAP(Continuous Positive Airway Pressure)联合肺表面活性物质治疗新生儿呼吸窘迫综合征(NRDS)临床疗效及对血气指标的影响。方法:选择2014年8月至2018年8月本院收治的新生儿呼吸窘迫综合征患者200例,将其随机分为2组,每组100例。A组给予CPAP(持续正压通气)联合肺表面活性物质治疗,B组给予CPAP(持续正压通气)治疗,分析和比较两组的临床疗效及治疗前后血气指标的变化。结果:治疗后,两组新生儿患者PaO_2均较治疗前均显著升高,PaCO_2较治疗前明显降低,且A组PaO_2显著高于B组(P0.05),PaCO_2显著低于B组(P0.05);A组住院时间显著短于B组(P0.05),临床总有效率显著高于B组(P0.05);两组新生儿患者的胸部X线评分均较治疗前显著降低(P0.05),A组12 h和24 h胸部X线评分均显著性低于B组(P0.05);A组PEEP/cmH_2O水平显著低于B组(P0.05),Fi O_2水平显著高于B组(P0.05);两组生儿患者的的OI指数均较治疗前显著升高,且A组明显高于B组(P0.05)。结论:CPAP联合肺表面活性物质治疗NRDS的临床效果显著优于单用CPAP(持续正压通气)治疗,且且可显著改善患儿血气指标。  相似文献   

19.
BackgroundAdenosine receptors are involved in tumor growth, progression, and response to therapy. Among them, A2B receptor is highly expressed in various tumors. Furthermore, ionizing radiation induces translocation of epidermal growth factor receptor (EGFR), which promotes DNA repair and contributes to radioresistance. We hypothesized that A2B receptor might be involved in the translocation of EGFR.MethodsWe investigated whether A2B receptor is involved in EGFR translocation and DNA damage response (γH2AX/53BP1 focus formation) of lung cancer cells by means of immunofluorescence studies. Radiosensitivity was evaluated by colony formation assay after γ-irradiation.ResultsA2B receptor was expressed at higher levels in cancer cells than in normal cells. A2B receptor antagonist treatment or A2B receptor knockdown suppressed EGFR translocation, γH2AX/53BP1 focus formation, and colony formation of lung cancer cell lines A549, calu-6 and NCI-H446, compared with a normal cell line (beas-2b). γ-Irradiation-induced phosphorylation of src and EGFR was also attenuated by suppression of A2B receptor expression.ConclusionActivation of A2B receptor mediates γ-radiation-induced translocation of EGFR and phosphorylation of src and EGFR, thereby promoting recovery of irradiated lung cancer cells from DNA damage.General significanceOur results indicate that A2B receptors contribute to radiation resistance in a cancer-cell-specific manner, and may be a promising target for radiosensitizers in cancer radiotherapy.  相似文献   

20.
《Journal of bryology》2013,35(4):743-746
Abstract

The spore wall ornamentation of B. indusiata (B. viridis) and B. aphylla has been characterized by SEM and is similar in both species. On the basis of the observations made, the authors define the spores of the two species as catalept and not atreme as reported in earlier literature.  相似文献   

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