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1.
In only a few perennial herbs is age determination of individual plants possible. The life cycle of Corydalis intermedia and C. solida is described. Plants have an age in years identical to the number of dead sheaths outside their underground tuber. Various ways to determine age in other species are reviewed: No. of dead layers around corm: Corydalis cava ; no. of dead layers around tuber: Corydalis pumila, Drosera erythrorhiza, D. bulbosa ; no. of dead remains of leaves/inflorescence stalks to the side of the corm: Philydrella pygmaea ; no. of collaterals in corm: Liatris aspera ; no. of nodes on rootstock: Trillium erectum ; and no. of bands of high and low density of leaf scars on stems: Aeonium species.  相似文献   

2.
The dissociation of a labeled ligand from a binding structure to which it is reversibly attached can be promoted either by dilution or by chase. The kinetics of the dissociation brought up by dilution can be modified or not by the presence of various concentrations of cold ligand, according to the molecular mechanism of interaction. Analog computer simulation leads to the following results: (i) no cooperativity, monomolecular dissociation: no modification; (ii) positive or negative cooperativity (sequential models): acceleration, no modification, or slowing down (according to the kinetic constants); (iii) positive cooperativity (concerted model): no modification; (iv) two-step interaction: no modification if both interaction steps take place in the same phase, otherwise acceleration; and, (v) bimolecular association and dissociation: acceleration. This methodology could be used in order to characterize the molecular properties of various binding structures in the field of drug and hormone receptors as well as in enzymology.  相似文献   

3.
Patient no 1, a boy, was carrier of a de novo del (14) (pter- greater than q23::q32- greater than qter). Patient no 2, a boy, had a de novo del (14) (pter- greater than q23::q24.2- greater than qter). Common dysmorphisms included bushy eyebrows, frontal bossing, and micrognathia. Patient no 2 had features of Holt-Oram syndrome, i.e. congenital heart defect and severe ulnar defect. Patient no 1 had congenital heart defect but no typical osseous disorders. The association of Holt-Oram syndrome and del 14q24.1 is stressed. Patient no 1 was heterozygous for Pl (alpha-1-antitrypsin) phenotypes. The gene locus could thus be excluded from q24 and q31, and tentatively assigned to q32.1.  相似文献   

4.
BackgroundPatients with psychiatric comorbidities represent a significant subset of those sustaining pilon fractures. The purpose of this study is to examine the association of psychiatric comorbidities (PC) in patients with pilon fractures and clinical outcomes.MethodsA multi-institution, retrospective review was conducted. Inclusion/exclusion criteria were skeletally mature patients with a tibia pilon fracture (OTA Type 43B/C) who underwent definitive fracture fixation utilizing open reduction internal fixation (ORIF) with a minimum of 24 weeks of follow-up. Patients were stratified into two groups for comparison: PC group and no PC group.ResultsThere were 103 patients with pilon fractures that met the inclusion/exclusion criteria of this study. Of these patients, 22 (21.4%) had at least one psychiatric comorbidity (PC) and 81 (78.6%) did not have psychiatric comorbidities (no PC). There was a higher percentage of female patients (PC: 59.1% vs no PC: 25.9%, p=0.0.005), smokers (PC: 40.9% vs no PC: 16.0%, p=0.02), and drug users (PC: 22.7% vs no PC: 8.6%, p=0.08) amongst PC patients. Fracture comminution (PC: 54.5% vs no PC: 32.1%, p=0.05) occurred more frequently in PC patients. The PC group had a higher incidence of weightbearing noncompliance (22.7% vs 7.5%, p=0.04) and reoperation (PC: 54.5% vs no PC: 29.6%, p=0.03).ConclusionPatients with psychiatric comorbidities represent a significant percentage of pilon fracture patients and appear to be at higher risk for postoperative complication. Risk factors that may predispose patients in the PC group include smoking/substance use, weightbearing noncompliance, and fracture comminution. Level of Evidence: III  相似文献   

5.
目的:初步评价一种新型瓷嵌体修复用树脂粘接材料的生物安全性。方法:按照国标GB16886.5-1997,医药行业标准YY/T0268-2001、YY/T0279-1995、以及YY/T 0244-1996所规定的方法对本院材料科新研制的复合树脂粘接材料的生物安全性进行评价,内容包括短期急性全身毒性试验,粘膜刺激实验,细胞毒性试验。结果:此种新型瓷嵌体修复用树脂粘接材料无细胞毒性,无短期全身毒性,对口腔黏膜无刺激。结论:此种新型瓷嵌体修复用树脂粘接材料具有良好的生物安全性,可以进行进一步安全性检测。  相似文献   

6.
汤明  陈森林  曾亮 《现代生物医学进展》2007,7(7):1039-1041,F0003
目的1观察热休克蛋白60和热休克蛋白27在结直肠癌中的表达及意义。方法:收集结直肠癌80例,其中淋巴结转移40例(转移组),无淋巴结转移40例(无转移组);另外,在结直肠癌80例中,有结直肠腺瘤(腺瘤组)以及距肿块15cm以上的正常肠粘膜(对照组)各40例。应用免疫组织化学SP法检测组织中蛋白的表达。结果:HSP60的表达主要定位在癌细胞胞浆,在对照组、腺瘤组、非转移组、转移组中的表达阳性率分别为25%、30%、57.5%、90%,组间比较发现,对照组与转移组、腺瘤组与转移组、转移组与非转移组(x^2=10.912,P〈0.001)的HSP60阳性表达率存在统计学差异;而对照组与腺瘤和非转移组间以及腺瘤与非转移组间无统计学差异。HSP27的表达主要定位在癌细胞的胞浆,在对照组、腺瘤组、非转移组、转移组的表达阳性率分别为5%,35%,50%,90%,组间比较发现,对照组分别与无淋巴结转移组、淋巴结转移组;腺瘤组分别与转移组;非转移组与转移组间存在统计学差异,腺瘤与非转移组间无统计学差异。HSP60和HSP27表达间无统计学相关。结论:HSP27表达可能与结直肠癌发生和转移相关。而HSP60的表达可能在结直肠癌转移中具有重要意义。  相似文献   

7.
The effect of 3 months exposure to short day length (L:D, 9:15) on spermatogenesis in R. cyanophlyctis was studied. There was no difference in the qualitative and quantitative aspect of spermatogenesis between control frogs exposed to ambient photoperiod (L:D, 12.16:11.44) and frogs exposed to short day light. The present findings indicate that light has no role in spermatogenesis in the frog.  相似文献   

8.
目的:观察不同能量输出的Er,C r:YSGG激光照射对牙周病牙根面的影响,探讨Er,C r:YSGG激光用于牙周治疗的可行性和有效性。方法:选择因牙周病松动Ⅲo而拔除牙12颗,随机分3组,每组4颗。分别以1.5 W、2.0 W、2.5 W激光照射。扫描电镜(SEM)观察各组牙根表面和纵剖面。结果:低倍镜下各组根面改变无明显差异,表面干净,粗糙程度均匀,未见明显弹坑状痕迹;高倍镜下1.5 W激光照射组显示根面粗糙程度更均匀一致,无弹坑状改变,无熔融、炭化迹象,未见牙本质小管暴露。结论:Er,C r:YSGG激光能有效去除牙周病牙根面玷污层及病变牙骨质,根面无熔融、炭化等改变。1.5 W激光照射组优于2.0 W组和2.5 W组。  相似文献   

9.
Increasing the proportion of an amino acid mixture corresponding to casein in a low-fat, cholesterol-free, semipurified diet fed to rabbits causes a progressive increase in serum total and low density lipoprotein cholesterol, and the effect appears to be due primarily to the essential amino acids in the mixture. Our recent studies have also shown that the variations in serum cholesterol in response to different levels of the amino acid mixture are not associated with any changes in fecal excretion of cholesterol or bile acids. Further attempts to understand the mechanism of action of dietary amino acids on serum cholesterol levels have shown the following: (1) no correlation with levels of plasma amino acids, either in the fasting or postprandial state: (2) no correlation with serum levels of thyroid hormones: (3) no relationship to activity of hepatic or intestinal microsomal hydroxymethylglutaryl coenzyme A reductase: (4) no corresponding effects on the activities of cholesterol esterifying enzymes of intestinal mucosa: and (5) no correlation with the degree of esterification of cholesterol in very low or low density lipoproteins. Further studies are required to identify the specific amino acids responsible for the hypercholesterolemic effects and to determine the mechanisms involved.  相似文献   

10.
目的:通过胆肠吻合缝合技术的改进,减少并发症的发生。方法:对52例肠道吻合手术采用降落伞式缝合。结果:降落伞式胆肠吻合时间平均20 min,明显缩短了手术时间,全部病例均未出现胆肠吻合漏,无死亡病例。结论:降落伞式胆肠吻合术具有操作简便、省时、并发症少等特点。  相似文献   

11.
We investigated the impact of obesity on the abnormalities of systolic and diastolic regional left ventricular (LV) function in patients with or without hypertension or hypertrophy, and without heart failure. We studied 120 individuals divided into 6 groups of 20 patients (42 ± 6 years, 60 females) using standard and pulsed-wave tissue Doppler imaging (TDI) echocardiography, and heterogeneity index (HI): nonobese (I: no hypertension, no hypertrophy, control group; II: hypertension, no hypertrophy; III: hypertension and hypertrophy) and obese (IV: no hypertension, no hypertrophy; V: hypertension, no hypertrophy; VI: hypertension and hypertrophy). The criterion for obesity was BMI ≥30 kg/m2, for hypertension was blood pressure ≥ 140/90 mm Hg, for hypertrophy in nonobese was LV mass/body surface area (BSA) >134 g/m(2) (men) and >110 mg/m2 (women), and in obese was LV mass/height(2.7) >50 (men) and >40 (women). Obese groups had normal LV ejection fraction compared with nonobese groups, but decreased longitudinal and radial systolic myocardial peak velocities (S'), and early diastolic myocardial peak velocity (E'). Also, a great variability of E' and late diastolic myocardial peak velocity (A') from the longitudinal basal region was observed in obese groups (E'basal nonobese: 11 ± 7 vs. obese 19 ± 11, P < 0.001, A'basal nonobese: 7 ± 4 vs. obese 11 ± 7, P < 0.001). Our findings were more evident when comparing groups IV with V and VI, with the latter having concentric hypertrophy and obvious segmental systolic and diastolic dysfunctions. Subclinical myocardial alterations and increased variability of the velocities were observed in obese groups, especially with hypertension and hypertrophy, reflecting impaired regional LV relaxation, segmental atrial, and systolic dysfunctions.  相似文献   

12.
A series of experiments was conducted to study the effects of dietary and injected lead (as Pb acetate-3H2O) and of dietary Cd, Hg, and Se on fatty acid composition of serum lipids of chicks as measured by gas-liquid chromatography. The effect of dietary Pb on fatty acid composition of erythrocyte membranes was measured also. Dietary Pb (1000 ppm) increased the serum concentration of arachidonic acid (20:4, first no. = no. of carbon atoms:second no. = no. of double bonds) and decreased the concentration of linoleic acid (18:2) and the ratio 18:2/20:4. Intraperitoneal injection of Pb (52 mg/100 g body weight) did not alter serum fatty acid composition by 4 h post-injection. The separate effects of 2000 ppm Pb, 60 ppm Cd, 500 ppm Hg, and 10 ppm Se added to the diet on serum fatty acids were measured in a single experiment. In comparison to controls, Pb and Cd lowered serum concentration of 18:2. Only Pb raised serum 20:4. Pb lowered the ratio 18:2/20:4, whereas Cd and Hg raised the ratio and Se was without effect. Dietary Pb (2000 ppm) raised the concentration of 20:4 and lowered the ratio 18:2/20:4 in erythrocyte membranes. The different effects of injected and dietary Pb on the serum 18:2/20:4 ratio suggest that Pb alters 20:4 synthesis from 18:2 rather than mobilization of 20:4 from tissues. The Pb-induced increase of lipid peroxida-tion in erythrocytes observed by other workers may be a reflection of increased 20:4 level in erythrocyte membranes.  相似文献   

13.
Summary Seeds of Nicotiana tabacum were allowed to imbibe water for 1 h and were then treated with 5–20 mM N-nitroso-N-methylurea (NMU) for 1 h. Seedlings were planted out separately and leaves no. 1–6 were scored individually after expansion was complete: frequencies of leaves with mutant sectors and the percentage of leaf area that was mutant were determined for the numbered leaves. Treatment with 5 mM NMU gave few mutant plants but after 10–20 mM NMU 50–98% of plants were mutant. The frequency of mutant leaves increased from leaf no. 1 to leaves no. 3–4; as much as a 5.6-fold increase, from leaf no. 1 to no. 3 was found. There appears to be differential sensitivity to NMU: it is lower in the initial cells for leaf no. 1 than in the initials for leaves no. 3 or 4. Leaves no. 1–4 arise from four different groups of initial cells: mutations appearing in two or more of leaves no. 1–4 must, therefore, arise independently of one another. From mutants found in leaves no. 1–4 it is estimated that the mean number of mutations per seedling was 2.68 after treatment with 20 mM NMU. Mean percentage of leaf surface area occupied by mutant sectors increased from 14% to 29.4% as NMU concentration increased from 10 to 20 mM. It also increased significantly from leaf no. 1 to leaves no. 3–6 after treatment with 15 or 20 mM NMU but not after 10 mM NMU: this suggests that mutagen treatment may affect the formation of mutant homoplasmon cells and their contribution to leaf primordia.  相似文献   

14.
The effect of photoperiod on sexual function and growth in weanling male and female collared lemmings (Dicrostonyx groenlandicus) was studied. Males and females maintained in 6 hr light:18 hr dark after weaning were larger at the end of 70 days than their siblings kept in 20L:4D. Males in 6L:18D were longer and overall body growth was greater. Males in 6L:18D had heavier adrenals but there were no differences in the weights of testes, preputial glands or seminal vesicles or in the mean testosterone levels of the two groups. Females in 6L:18D had heavier preputial glands than the 20L:4D females. There were no differences between the two groups in uterine, ovarian or adrenal weights or in the number or mean size of atretic or healthy Graafian follicles. Adult males kept in 6L:18D increased more in body weight than those in 20L:4D, but there was no detectable influence of the short photoperiod on reproductive function.  相似文献   

15.
Purpose: The aim of this study was to model the relationship between risk factors of postpartum depression and quality of life in Iranian women. Methods: In this study, 306 women were included as a sample. The study tools of the Edinburgh Postpartum Depression Inventory included items such as socioeconomic characteristics, recent pregnancy history and outcome, and Quality of Life Questionnaire (SF-12). SPSS software was used for data analysis and a significance value of 0.05 was considered. Results: Most participants were homemakers with no instances of abortion, no stillbirth, no history of depression, no preterm delivery, no difficulties during pregnancy, no difficulties during delivery, no unplanned pregnancy, no smoking during pregnancy, had family support during pregnancy and after delivery, type of delivery was cesarean, had a healthy baby and satisfaction with neonatal sex, and never or rarely experienced partner violence. Their mean age, years of education, living arrangements, and breastfeeding of participants respectively were 29.73±5.42, 14.64±1.96, 1.09±0.53, and 5.61±2.98. The prevalence of postpartum depression was 5.6%. According to the path analysis, living arrangements with β=0.73 had the most direct effect and occupation with β=0.69 had the most indirect effect on postpartum depression. Conclusions: According to the path analysis model, postpartum depression is affected by many factors such as age, years of education, occupation, living arrangements, and quality of life.  相似文献   

16.
Objective: To compare weight regain, satisfaction, and convenience among three weight maintenance programs: telehealth, traditional classes, and no program. Research Methods and Procedures: This quasi‐experimental study compared weight change, satisfaction, and convenience among three program types. The telehealth participants interacted with a registered dietitian (RD) through the web and e‐mail, traditional program participants attended a traditional classroom program, and no program participants received no interaction. Eighty‐seven subjects (14 men and 73 women) were enrolled in the study: 31 traditional, 31 telehealth, and 25 no program participants. Eligibility included participation in a community‐based weight loss program (Colorado Weigh) and minimum 7% weight loss before enrollment. Results: Subject characteristics at baseline were as follows: age, 50 ± 9.3 (standard deviation) years; height, 1.68 ± 0.09 m; weight, 80.5 ± 18.4 kg, with no significant differences between groups. Over 6 months, the traditional group lost 0.5 ± 4.3 kg, the telehealth group lost 0.6 ± 2.5 kg, and the no program group gained 1.7 ± 3.0 kg. Weight change among all three groups was significant (p = 0.02); no program participants gained significantly more weight than the telehealth and traditional groups. There were no differences in overall satisfaction between the telehealth and traditional groups (p = 0.43), but individuals in the telehealth group rated their program as more convenient compared with the traditional group (p = 0.0001). Discussion: These results show the usefulness of telehealth programs in long‐term weight loss maintenance. They may be a useful alternative for those who successfully lose weight in a structured behavioral program but do not choose to participate in a formal behavioral weight loss maintenance program.  相似文献   

17.
目的:通过研究束缚浸水应激对大鼠肝胆汁分泌的影响,探讨其作用机制。方法:实验分6组(n=8):A组:室温下单纯束缚+生理盐水;B组:束缚浸水应激+生理盐水;C组:室温下单纯束缚+阿托品;D组:束缚浸水应激+阿托品;E组:室温下单纯束缚+酚妥拉明;F组:束缚浸水应激+酚妥拉明。结果:与A组比较,B组肝胆汁分泌量显著减少(P〈0.05),pH值显著升高(P〈0.01);与A组比较,C组肝胆汁分泌量变化不明显,只有微量减少:E组与A组相对照肝胆汁分泌量无明显变化,但也有微量减少。与B组比较,D组肝胆汁分泌量有明显变化(P〈0.05),肝胆汁pH无明显变化;F组与B组对照其肝胆汁分泌量有明显变化(P〈0.05),肝胆汁pH无明显变化;D组与F组对照肝胆汁分泌量无明显变化,肝胆汁pH无明显变化。结论:束缚浸水应激对大鼠肝胆汁分泌有明显地抑制作用。浸水应激组肝胆汁的分泌量明显减少,肝胆汁的pH明显升高;迷走神经、交感神经在室温单纯束缚的情况下对肝胆汁的分泌影响较小,而在束缚浸水的情况下迷走神经、交感神经对肝胆汁的分泌有较显著的影响(P〈0.05)。  相似文献   

18.
ROSO: optimizing oligonucleotide probes for microarrays   总被引:1,自引:0,他引:1  
ROSO is software to design optimal oligonucleotide probe sets for microarrays. Selected probes show no significant cross-hybridization, no stable secondary structures and their Tm are chosen to minimize the Tm variability of the probe set. AVAILABILITY: The program is available on the internet. Sources are freely available, for non-profit use, on request to the authors. Supplementary information: http://pbil.univ-lyon1.fr/roso  相似文献   

19.
Small mammals were trapped on five islands for short periods during the summers of 1964 and 1965, with the following results:
Handa: Rattus norvegicus only, probably no other species present.
Muck: Sorex araneus, S. minutus, Apodemus sylvaticus and Microtus agrestis; R. norvegicus also present.
Pabay: S. minutus and Neomys fodiens ; probably no other species present.
Scalpay: S. araneus, S. minutus and M. agrestis.
Soay: S. araneus and S. minutus ; rodents almost certainly absent.
Ectoparasites (fleas and Acarina) collected from these small mammals are tabulated.  相似文献   

20.
目的:探讨胃癌患者远端胃大部切除术后放置鼻胃管引流的短期效果。方法:选取我科从2010年9月1日到2013年3月1日间318例胃癌行远端胃切除的患者,随机分为术后留置鼻胃管(NGT组)或不留置组(no NGT组),比较两组间围手术期的短期效果。结果:158例患者纳入NGT组,而160例患者纳入no NGT组。两组间在术后腹胀、持续呕吐、吻合口瘘、发热、肺部感染、伤口感染的发生率上无统计学差异(P0.05)。进一步分析65例既往有腹部手术史的患者(NGT组34例vs no NGT组31例),NGT组腹胀发生率(5.88%vs 29.03%,P0.05)显著低于no NGT组。结论:对于胃癌患者行远端胃切除术后不推荐放置鼻胃管;而对于既往有腹部手术史的患者,术后放置胃管可以降低腹胀的发生。  相似文献   

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