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1.
Little attention has been devoted to assessing the reproducibility of (paleo)pathological observations. Harris lines (HL) are among the markers most used to determine chronology of stresses suffered during growth. Nevertheless, their scoring entails remarkable methodological difficulty. Bone sections (S) and radiographs (R) of 29 adult tibiae of archeological provenance (medieval) were scored for HL by five observers. At regular intervals of time, each observer gave two independent counts on both series. Results show a) a substantial interobserver disagreement of HL estimates for both sectional and radiographic records, and b) a high level of intraobserver error. © 1994 Wiley-Liss, Inc.  相似文献   
2.
Apophua simplicipes (Cresson) (Hymenoptera: Ichneumonidae) is a common parasitoid of the oblique banded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae) in organically managed apple orchards in the southern interior of British Columbia, Canada. The biological characteristics of a laboratory colony of A. simplicipes were studied. When held at 15 and 25°C and provided with honey water, individual females survived an average of 60.6±6.1 and 29.8±4.7 days, oviposited 196.7±50.7 and 326.6±51.3 eggs and parasitized a total of 163.4±40.4 and 229.4±35.8 hosts, respectively. Females oviposited into first through fourth instar oblique banded leafrollers, with significantly more parasitism occurring in the first two instars compared to the third and fourth instars. No parasitoid larvae survived past the first larval stage in parasitized fourth instar hosts. Apophua simplicipes did not parasitize larvae of three-lined leafroller, Pandemis limitata (Robinson) (Lepidoptera: Tortricidae) which is sympatric with oblique banded leafrollers in orchards in the southern interior of British Columbia. Female predation and host feeding from wounds on early instars of both leafroller species was observed under laboratory conditions. In addition, early instar hosts exited diet feeding sites in response to the probing activity of the ovipositing wasps. A similar escape reaction in the orchard may cause a leafroller larva to move away from its feeding site, making it more vulnerable to predation or movement off the tree. Apophua simplicipes larvae emerged from fifth and sixth instar hosts. Parasitized oblique banded leafroller hosts consumed significantly less meridic diet than unparasitized female larvae from fifth instar through to parasitoid emergence or leafroller pupation. Our laboratory results suggest that A. simplicipes may reduce field populations of oblique banded leafroller and decrease pest feeding damage.  相似文献   
3.
The morphological characters of Pterophyllum guizhouense sp. nov. were reported and those of P. astartense Harris were supplied and emended. Meanwhile, the significance of cuticle characters chosen in the identification of fossil plants was also discussed.  相似文献   
4.
目的:探讨人工髋关节置换术在治疗股骨头缺血性坏死(ANFH)中的临床疗效。方法:选择2007 年2 月-2011 年2 月我院收 治的320 例(340 髋)股骨头缺血性坏死患者,均采用人工髋关节置换术对患者进行治疗,其中160 例(172 髋)患者应用骨水泥型 假体进行治疗,另外160 例(168)患者采用非骨水泥型假体进行治疗。采用Harris评分对患者手术前后的髋关节功能情况进行评 价,并比较骨水泥治疗组和非骨水泥治疗组的临床疗效。结果:患者均获得随访,随访时间为3~18 个月。全部患者手术后的 Harris评分明显高于手术前,差异有统计学意义(P<0.05)。骨水泥治疗组和非骨水泥治疗组在术后出血量、术后Harris 评分及住 院时间方面的差异无统计学意义(P>0.05),但非骨水泥治疗组的并发症发生率明显低于骨水泥治疗组(P<0.05)。结论:采用人工 髋关节置换术治疗ANFH疗效显著,能明显改善患者的生活质量,骨水泥型假体与非骨水泥型假体的治疗效果相当,应根据患者 的具体情况进行合理的选择。  相似文献   
5.
光周期对两种色型豌豆蚜种群参数的影响   总被引:1,自引:0,他引:1  
马亚玲  刘长仲 《生态学报》2016,36(14):4548-4555
为探讨光周期对红绿两种色型豌豆蚜种群增长的影响,于室内模拟光周期22L∶2D、16L∶8D、10L∶14D和4L∶20D四个水平,研究了红绿两种色型豌豆蚜的发育、繁殖和生命表。结果表明:相对于其它光周期,在光周期22L∶2D时,红绿两种色型豌豆蚜若蚜存活率最高,繁殖力最强;其红色型豌豆蚜种群增长内禀增长率(r_m=0.3263)高于绿色型豌豆(r_m=0.2863)。光周期16L∶8D时,红色型豌豆蚜的若蚜存活率(72.22%)高于绿色型豌豆蚜(69.45%),而成蚜寿命(6.58d)较短;但绿色型豌豆蚜内禀增长率(r_m=0.2648)高于红色型豌豆蚜(r_m=0.2249),其种群繁殖力强。光周期10L∶14D时,红色型豌豆蚜与绿色型豌豆蚜相比,若蚜存活率(80.55%)高,内禀增长率(r_m=0.2490)高,种群增长力强,而绿色型豌豆蚜成蚜寿命(12.71d)较长。光周期4L∶20D时,两种色型豌豆蚜若蚜存活率最低,繁殖力最弱,成蚜寿命显著延长;红色型豌豆蚜若蚜存活率(64.67%)高于绿色型(35.50%),成蚜没有产生后代;绿色型豌豆蚜内禀增长率(r_m=-0.0366),其种群为负增长。综上,短光照条件(4L∶20D)延长了两种色型豌豆蚜的若蚜发育历期及成蚜寿命,降低了若蚜存活率、繁殖力及生命表各项参数;长光照条件(22L∶2D)缩短了两种色型豌豆蚜的若蚜发育历期及成蚜寿命,若蚜存活率高、繁殖力强;红色型豌豆蚜更适宜光周期10L∶14D,而绿色型豌豆蚜更适宜光周期16L∶8D。  相似文献   
6.
Hypoplastic defects of tooth enamel and Harris lines in the long bones have been heralded as potentially useful indicators of health conditions in prehistoric populations. Both result from temporary cessation of growth processes due to similar types of disease, malnutrition, or other metabolic insult. An association test for the first six years of life was conducted on a large series of prehistoric California Indians, using femora and canines from young adults. No significant association was found. This is ascribable to differences in etiology and stability.  相似文献   
7.

Background

Avascular necrosis (AVN) of femoral head is a progressive bone disease due to ischemia of femoral head; patients experience pain and they can not do normal activity. There is not an effective way to treat the cause of this disease. In recent studies, treatment of this disease using pluripotent stem cell–derived mesenchyme is safe and effective, but this method needs more investigation. In this study, the safety and efficacy of CD133+ cells were evaluated as a novel method of stem cell therapy to treat AVN.

Methods

In this prospective quasi-experimental study, the participants were selected among patients with AVN who were referred to the Royan Cell Therapy Center. Autologous bone marrow–derived CD133+ cells were injected into the necrotic site of the femoral head during core decompression (CD). The Visual Analogue Scale (VAS), Harris Hip Score (HHS), Western Ontario and McMaster Universities Arthritis Index (WOMAC) and walking distance (WD) were measured before and 2, 6 and 12 months after CD.

Results

Overall, nine patients (six men and three women) were investigated in this study. Their mean age was 26 years old. All of them significantly improved in VAS, HHS, WOMAC and WD scores and they could do more activity without pain. Also, imaging findings demonstrated significant reductions in joint injuries. Significant complications were not seen in patients.

Discussion

This prospective quasi-experimental study demonstrated that, in patients with AVN, a single bone marrow–derived CD133+ cell injection into the necrotic site of the femoral head during CD is safe and effective in providing significant, clinically relevant pain relief and patients could do more activity over 2, 6 and 12 months. This pilot study suggested further clinical trials over an extended assessment period to approve bone marrow–derived CD133+ cell injection to treat AVN.  相似文献   
8.
Leptospirosis, a widespread zoonosis, is a re-emerging infectious disease caused by pathogenic Leptospira species. In Taiwan, Leptospira santarosai serovar Shermani is the most frequently isolated serovar, causing both renal and systemic infections. This study aimed to generate a L. santarosai serovar Shermani genome sequence and categorize its hypothetical genes, particularly those associated with virulence. The genome sequence consists of 3,936,333 nucleotides and 4033 predicted genes. Additionally, 2244 coding sequences could be placed into clusters of orthologous groups and the number of genes involving cell wall/membrane/envelope biogenesis and defense mechanisms was higher than that of other Leptospira spp. Comparative genetic analysis based on BLASTX data revealed that about 73% and 68.8% of all coding sequences have matches to pathogenic L. interrogans and L. borgpetersenii, respectively, and about 57.6% to saprophyte L. biflexa. Among the hypothetical proteins, 421 have a transmembrane region, 172 have a signal peptide and 17 possess a lipoprotein signature. According to PFAM prediction, 32 hypothetical proteins have properties of toxins and surface proteins mediated bacterial attachment, suggesting they may have roles associated with virulence. The availability of the genome sequence of L. santarosai serovar Shermani and the bioinformatics re-annotation of leptospiral hypothetical proteins will facilitate further functional genomic studies to elucidate the pathogenesis of leptospirosis and develop leptospiral vaccines.  相似文献   
9.
目的:分析髋关节置换术对股骨头坏死(osteonecrosis of the femoral head,ONFH)患者的髋关节Harris功能评分(Harris hip score,HHS)与简式Fugl-Meyer运动功能评分(Fugl-Meyer assessment scale,FMA)的影响。方法:回顾性选取于我院受诊的ONFH患者87例,按照其所用术式的不同,分为两组,传统组采用传统股骨头置换术治疗,共43例病例;研究组采用无柄解剖型人工髋关节置换术治疗,共44例,比较两组Harris评分、Fugl-Meyer运动功能评分的改变及统计并发症信息。结果:研究组Harris评分无显著差异(P0.05);治疗后,研究组Harris评分明显高于传统组(P0.05);研究组简式Fugl-Meyer运动功能显著优于传统组(P0.05);研究组并发症的发生率低于传统组(P0.05)。结论:无柄解剖型人工髋关节置换术治疗ONFH的临床疗效显著,能够改善患者髋关节功能及运动功能。  相似文献   
10.
A simple method for determining the age of an individual at the time of radiopaque transverse (Harris) line formation is presented. To use this method, only two measurements are required: total bone length and distance of line to nearest bone end; these are put into formulae that calculate the percent of total bone growth when the line appeared. The result of this calculation is compared with tables of percent bone growth per year (one to 16 years in females and one to 18 years in males) to arrive at estimations of age at line formation. Since these tables are presented for the femur, tibia, humerus, and radius, this technique can be used on any one of the major long bones exhibiting lines.  相似文献   
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