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91.
The phylogeny of howler monkeys (Alouatta, Platyrrhini): Reconstruction by multicolor cross-species chromosome painting 总被引:2,自引:0,他引:2
Edivaldo H. C. de Oliveira Michaela Neusser Wilsea B. Figueiredo Cleusa Nagamachi Julio Cesar Pieczarka Ives J. Sbalqueiro Johannes Wienberg Stefan Müller 《Chromosome research》2002,10(8):669-683
We performed multidirectional chromosome painting in a comparative cytogenetic study of the three howler monkey species Alouatta fusca, A. caraya and A. seniculus macconnelli (Atelinae, Platyrrhini) in order to reconstruct phylogenetic relationships within this genus. Comparative genome maps between these species were established by multicolor fluorescence in-situ hybridization (FISH) employing human, Saguinus oedipus and Lagothrix lagothricha chromosome-specific probes. The three species included in this study and previously analyzed howler monkey species were subjected to a phylogenetic analysis on the basis of a data matrix comprised of 98 discrete molecular cytogenetic characters. The results revealed that howler monkeys represent the genus with the most extensive karyotype diversity within Platyrrhini so far analyzed with high levels of intraspecific chromosomal variability. Two different multiple sex chromosome systems were identified. The phylogenetic analysis indicated that Alouatta is a monophyletic clade which can be derived from a proposed ancestral Atelinae karyotype of 2n=62 chromosomes by a chromosome fusion, a fission, a Y-autosomal translocation and a pericentric inversion. Following these suggestions, the genus Alouatta can be divided into two distinct species groups: the first includes A. caraya and A. belzebul, the second A. s. macconnelli, A. sara, A. s. arctoidea and A. fusca. 相似文献
92.
镉对大鼠肾脏和睾丸毒性的比较 总被引:2,自引:0,他引:2
大鼠饮水中给镉12wk后,检测了尿低分子蛋白(LMWP)排出量。尿碱性磷酸酶(ALP)活性,血清睾酮水平,睾丸乳酸脱氢酶同功酶(LDH-X)活性,精子计数和形态,雄鼠生育力,肾,睾丸和附睾组织镉含量,并在光镜和电镜下观察上述组织的病理变化,从生化,形态和功能改变三方面比较了大鼠肾脏和睾丸对镉的敏感性,发现尿LMWP和ALP仅在高剂量组显著增加,而血清睾酮和睾丸LDH-X在中剂量纽和低剂量纽已明显降低,说明镉对睾丸的有害作用可出现在肾脏之前。 相似文献
93.
K. Miyashita I. Morioka T. Tanabe H. Iwata S. Takeda 《International archives of occupational and environmental health》1992,64(5):347-351
Summary To study the effects of construction machinery operation on subjective symptoms, a questionnaire survey was caried out among construction machinery operators by a self-reporting method. Subjects were 184 power shovel operators, 127 bulldozer operators, 44 forklift operators as operator groups, and 44 office workers as a control. Their ages were in a range of 30–49 years. The questionnaire contained 20 symptoms referring to fatigue, digestive problems, and upper or lower limbs or back problems. The prevalence rate and symptom characteristics were examined. The dominant symptoms of the operator groups were stiff shoulder, low back pain, and stomack symptoms. The prevalence rate of low back pain was significantly different between forklift operators and controls. No significant differences were found in the symptoms of upper limbs and fingers between operator groups and controls. The prevalence of Raynaud's phenomenon was 0.5%–2.3% in the operator groups and 2.3% in the control group. 相似文献
94.
A. C. Metting van Rijn A. Peper C. A. Grimbergen 《Medical & biological engineering & computing》1991,29(4):433-440
A multichannel instrumentation amplifier, developed to be used in a miniature universal eight-channel amplifier module, is
described. After discussing the specific properties of a bioelectric recording, the difficulties of meeting the demanded specifications
with a design based on operational amplifiers are reviewed. Because it proved impossible to achieve the demanded combination
of low noise and low power consumption using commercially available operational amplifiers, an amplifier equipped with an
input stage with discrete transistors was developed. A new design concept was used to expand the design to a multichannel
version with an equivalent input noise voltage of 0·35 μV RMS in a bandwidth of 0·1–100 Hz and a power consumption of 0·6
mW per channel. The results of this study are applied to miniature, universal, eight-channel amplifier modules, manufactured
with thick-film production techniques. The modules can be coupled to satisfy the demand for a multiple of eight channels.
The low power consumption enables the modules to be used in all kinds of portable and telemetry measurement systems and simplifies
the power supply in stationary measurement systems. 相似文献
95.
Effects of Clodronate on Cortical and Trabecular Bone in Ovariectomized Rats on a Low Calcium Diet 总被引:5,自引:0,他引:5
T. S. Kaastad O. Reikerås J. E. Madsen S. Narum J. H. Strømme K. J. Obrant L. Nordsletten 《Calcified tissue international》1997,61(2):158-164
The aim of this study was to evaluate the contribution of a low calcium diet to the cortical and trabecular osteoporosis
seen in ovariectomized rats after 7 weeks on a low calcium diet and to investigate the effects of the bisphosphonate clodronate
on this development of osteoporosis. Thirty-six mature, female Wistar rats were randomized into four groups: Ovx−B (bisphosphonate)
and Ovx−C (control) were ovariectomized, and Sham−Ca (low calcium) and Sham+Ca (normal calcium) were sham operated. The first
three groups were fed a low calcium diet (0.01%) and Sham+Ca normal rat chow (Ca 1.1%). The Ovx−B received 10 mg/kg s.c. clodronate
daily for nine weeks, and Ovx−C, Sham−Ca, and Sham+Ca received the same volumes of saline. Bone mineral turnover measured
as 85Sr-uptake was increased in all low calcium groups compared to Sham+Ca. The Sham+Ca femora had higher dry weight and ash weight
than the other groups, and Ovx−C had higher dry weight compared with Ovx−B and Sham−Ca. Calcium content was lower in both
Ovx groups compared to both Sham groups. Magnesium was lower in all groups compared to Sham+Ca and higher in Ovx−B compared
with Ovx−C. In the femoral shaft, Sham+Ca had significantly higher ultimate bending moment, energy absorption, and deflection
compared to the other three groups. Ultimate bending moment was higher in Sham−Ca than in Ovx−C. Stiffness was increased in
both Sham+Ca and Ovx−B compared to Ovx−C. The maximum stress in the femoral midshaft was higher in Sham+Ca than in the other
groups, and higher in Ovx−B than in Ovx−C. Histomorphometry showed increased medullary area in all low calcium groups compared
to Sham+Ca and larger cortical area in Sham+Ca and Ovx−B compared to Ovx−C. Compared to Sham+Ca the trabecular bone volume
was decreased to 30% in Sham−Ca and to 9% in Ovx−C, but was unchanged in Ovx−B. The low calcium diet generally increased bone
mineral turnover and reduced the tibial bone volume. Femoral changes led to a reduction of cortical fracture strength and
maximal stress. Ovariectomy in addition to a low calcium diet reduced femoral strength even more. Daily injections of clodronate
to ovariectomized rats on a low calcium diet increased femoral shaft stiffness and maximum stress, and clodronate preserved
both trabecular and cortical tibial bone volume completely.
Received: 11 June 1996 / Accepted: 5 March 1997 相似文献
96.
M. J. Ray P. A. Carroll S. J. E. Just G. A. T. Hawson J. H. N. Belt 《Journal of clinical monitoring and computing》1994,10(2):97-100
Objective. The Ciba Corning 512 coagulation monitor (CC512) can be used to monitor heparin therapy by performing an activated
partial thromboplastin time (APTT) at the patient’s bedside. This study was designed to compare the CC512 results to results
using the laboratory system. The relative sensitivities of both systems to the effect of oral anticoagulant therapy also was
investigated.Methods. Activated partial thromboplastin times were performed with both the CC512 and laboratory system on 74 specimens from patients
receiving IV heparin therapy, and on 14 specimens from patients on warfarin only. Heparin assays were performed on 43 of the
specimens from the heparinized patients.Results. When a patient was receiving heparin only, the APTT results of the CC512 proved to be similar to existing laboratory methods.
The CC512 APTT results of patients on warfarin only were markedly prolonged, whereas the laboratory APTTs were only slightly
affected.Conclusion. The CC512 results were comparable to the laboratory system. However, the CC512 APTT was more sensitive to the effect of
warfarin than the laboratory APTT system used in this study. CC512 APTT results on a patient receiving both oral and intravenous
anticoagulation could be misleading.
The authors wish to thank D.M. O’Brien and the nursing staff of the Coronary Care Unit for providing CC512 data and laboratory
specimens, and I. Smith for the preparation of graphics. We also wish to thank Australian Diagnostics Corporation, which provided
consumables. 相似文献
97.
目的了解延边地区警察人群的血脂水平。方法将382例(男350例,女32例;朝鲜族165例,汉族217例)延边少数民族自治州公安局职工作为观察组,将100例健康人群作为对照组,应用日立7600生化分析仪分别测定甘油三酯(TG)、总胆固醇(CHO)、高密度脂蛋白胆固醇(HDL—C)、低密度脂蛋白胆固醇(LDL—C),并进行对比分析。结果观察组检出血脂异常者220例,占58.9%;对照组28例,占28%,两者差异有统计学意义(Х^2=27.78,P〈0.01),观察组明显高于对照组。此外,观察组中朝鲜族与汉族的血脂异常率差异无统计学意义(P〉0.05),但男女差异显著(P〈0.01)。结论延边地区警察人群的血脂代谢异常率明显高于普通人群,无民族差异,提示该人群应及早加强健康教育和其他预防措施。 相似文献
98.
Loading anticancer drugs into HDL as well as LDL has little affect on properties of complexes and enhances cytotoxicity to human carcinoma cells 总被引:5,自引:0,他引:5
Low density lipoprotein (LDL) has been found to represent a suitable carrier for cytotoxic drugs that may target them to cancer. This study investigated whether very low density lipoprotein (VLDL), LDL and high density lipoprotein (HDL) can be used to effectively incorporate four cytotoxic drugs, 5-fluorouracil (5-FU), 5-iododeoxyuridine (IUdR), doxorubicin (Dox) and vindesine; characterized the complexes; and examined the effect of incorporation on drug cytotoxicity against HeLa cervical and MCF-7 breast carcinoma cells. Significant drug loading was achieved into all three classes of lipoproteins, consistent with the sizes and hydrophobicity of the drugs. The relative loading efficiency was found to be vindesine>IUdR>Dox>5-FU for all three classes of lipoproteins. As shown by electron microscopy (EM), drug incorporation did not affect the size or morphology of the lipoproteins. Differential scanning calorimetry (DSC) showed that drug loading did not significantly change the thermal transition temperature of core lipids in the lipoproteins. The transition enthalpy was changed only for LDL–Dox and LDL–vindesine. The drugs remained stable in the lipoproteins as determined by high performance liquid chromatography (HPLC). EM, DSC and HPLC data suggest that drugs were incorporated into lipoproteins without disrupting their integrity and drugs remained in their stable forms inside lipoproteins. Compared with free drugs in cytotoxicity assays, the IC50 values of LDL– and HDL–drug complexes were significantly lower (2.4- to 8.6-fold for LDL complexes and 2.5- to 23-fold for HDL complexes). All free or lipoprotein-bound drug formulations were comparably more cytotoxic against MCF-7 than HeLa cells. Upregulating the lipoprotein receptors enhanced, and downregulating them inhibited, the cytotoxicity, indicating the mechanistic involvement of lipoprotein receptor pathways. Complexes of all four drugs with VLDL, in contrast to LDL and HDL, had the same cytotoxicity as the four corresponding free drugs. Our results suggest that further studies are required of the potential of HDL to be a cancer targeting drug carrier. 相似文献
99.
应用荧光探针H2DCF-DA检测光照致细胞内活性氧产生的初步研究 总被引:1,自引:1,他引:0
目的应用荧光显微镜及新型荧光探针H2DCF-DA检测在光源照射过程中人脐静脉血管内皮细胞(ECV304)内活性氧的产生情况。方法将ECV304细胞接种于35mm培养皿中,24h后加入H2DCF-DA,使其终浓度为10μmol/L,孵育30min。利用荧光显微镜的激发光源作为照射光源,在采集荧光图像的同时完成光源照射,光源输出波长范围为460~490nm,功率密度约为100mW/cm2。连续采集DCF的荧光图,观察细胞内DCF荧光的变化情况,采用计算机图像处理和分析技术,求得细胞内不同照射时间点DCF平均荧光强度,进而得到平均荧光强度-时间曲线。另外,使用线粒体特异标记探针MitoFluorRed589与H2DCF-DA共同孵育细胞,分别采集同一细胞的DCF的荧光图和MitoFluorRed589的荧光图,并利用像素-荧光强度分析方法来确定DCF荧光在细胞内的分布位置。结果在光源照射的开始阶段,ECV304细胞内的DCF荧光强度迅速增加,在第10s时便上升至第2s时的2.2倍,但是随着照射时间逐渐延长,荧光强度增幅逐渐变小,到第60s时上升至第2s时的4.7倍。观察时间进一步延长,DCF的荧光强度的变化似乎进入平台期,继而开始出现下降。考察DCF荧光在ECV304细胞内的分布位置主要通过比较细胞内不同区域的I1/I2值,通过图像分析与计算得到线粒体区、细胞核区以及细胞质非线粒体区内I1/I2值分 相似文献
100.
肝素钠软膏(海普林)治疗皮质类固醇激素依赖性皮炎疗效观察 总被引:3,自引:0,他引:3
目的观察肝素钠软膏(海普林)治疗皮质类固醇激素依赖性皮炎的效果。方法随机抽取部分病例组成对照组,其余病例组成治疗组,分别使用单纯乳剂和肝素钠软膏外涂,配合相关内服药物治疗,比较治疗组和对照组疗效。结果对照组治疗有效率为24.81%,治疗组治疗有效率为52.24%,两组结果差异有非常显著性。结论应用肝素钠软膏外用治疗皮质类固醇激素依赖性皮炎取得了满意的疗效。 相似文献