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21.
Summary Intraspecific and reciprocal interspecific crosses involving Zinnia angustifolia clones and Z. elegans lines showed that in both species, sporophytic self-incompatibility (SI) systems were present. Intensity of SI varied among clones and lines, and high self seed set was associated with a concomitant decrease in callose fluorescence in papillae and pollen tubes. Incomplete stigmatic inhibition of pollen germination and tube growth was observed in reciprocal interspecific crosses and associated with callose synthesis, suggesting S-gene activity. Seed set and progeny obtained following Z. angustifolia×Z. elegans matings was comparable to intraspecific compatible matings of Z. angustifolia although the rate of pollen tube growth through the style was slower. In Z. elegans × Z. angustifolia matings, additional prezygotic barriers were present and acted between pollen tube penetration of the stigma and syngamy. SI X SI interspecific incompatibility was essentially unilateral, with no embryos or progeny obtained when Z. elegans was the pistillate parent. It was hypothesized that nonfunctioning of Z. elegans × Z. angustifolia crosses was due to S-gene expression at the stigmatic surface and to other isolating mechanisms in the stylar or ovarian transmitting tissue.Scientific Article No. A-4448, Contribution No. 7439 of the Maryland Agricultural Experiment Station, Department of HorticultureA portion of this paper was presented in the report: Boyle TH, Stimart DP (1986) Incompatibility relationships in intra- and interspecific crosses of Z. elegans Jacq. and Z. angustifolia HBK (Compositae). In: Mulcahy D (ed) Biotechnology and ecology of pollen. Springer, New York  相似文献   
22.
目的:探讨不同术式对颞叶癫痫患者术后认知功能、记忆能力以及生活质量的影响。方法:选取2014年2月~2018年4月期间我院收治的103例颞叶癫痫患者为研究对象,根据随机数字表法将患者分为单侧前颞叶切除术(ATL)组(n=51,给予ATL治疗)和选择性海马杏仁核切除术(SAH)组(n=52,给予SAH治疗),比较两组患者的手术疗效、术后认知功能、记忆能力、生活质量以及并发症。结果:两组术后6个月临床总有效率比较差异无统计学意义(P0.05)。两组患者术后6个月生活质量量表各项评分均较术前升高(P0.05)。两组患者术后6个月总智商(FIQ)、语言智商(VIQ)评分均较术前升高,且SAH组高于ATL组(P0.05)。两组术后6个月优势半球侧记忆商数(MQ)评分降低,非优势半球侧MQ评分升高(P0.05);SAH组术后6个月非优势半球侧MQ评分高于ATL组(P0.05)。两组患者术后并发症发生率比较无统计学差异(P0.05)。结论:颞叶癫痫患者采用ATL、SAH术式治疗,可获得相似的治疗效果,安全性均较好,但SAH术式在保护患者的认知功能及记忆能力方面更优。  相似文献   
23.
目的:探讨单侧与双侧穿刺入路经皮椎体后凸成形术(PKP)对骨质疏松性胸腰椎压缩骨折(OVCF)患者手术效果、生活质量以及血清应激因子的影响。方法:回顾性选取2016年7月~2019年7月期间我院接收的行PKP的OVCF患者83例。根据入路方式的不同分为A组(n=41,单侧穿刺入路)和B组(n=42,双侧穿刺入路),对比两组患者围术期指标、影像学指标、视觉模拟评分法(VAS)评分、Oswestry腰椎功能障碍指数(ODI)评分、健康调查生活质量量表(SF-36)评分、血清应激因子以及并发症发生情况。结果:A组手术时间短于B组,骨水泥用量、术中透视次数少于B组(P0.05)。两组术后6个月VAS评分、ODI评分降低,SF-36评分升高(P0.05)。两组术后3d去甲肾上腺素(NE)、肾上腺素(E)、皮质醇(Cor)均升高,但A组低于B组(P0.05)。两组术后6个月椎体前缘高度、后凸Cobb角均升高(P0.05)。两组并发症发生率比较差异无统计学意义(P0.05)。结论:单侧穿刺入路PKP可获得与双侧穿刺入路PKP相当的治疗效果和安全性,同时可缩短手术时间,减少骨水泥用量及术中透视次数,减轻机体应激反应。  相似文献   
24.
目的明确肾脏纤维化中波形蛋白表达在上皮-间充质转分化观察中的意义。方法雄性SD大鼠12只,随机分成假手术组和模型组,模型组行单侧输尿管梗阻术。造模后14天处死大鼠,分别采用免疫组织化学染色和Western印迹法对梗阻侧肾组织波形蛋白和α平滑肌肌动蛋白作定性和定量检测。并通过体外实验用TGF-β1刺激诱导人近端小管上皮细胞株(HK-2)发生上皮-间充质转分化。采用间接免疫荧光法对E-钙粘蛋白和波形蛋白进行染色,采用激光共聚焦显微镜观察细胞形态改变,并用蛋白印迹法定量检测HK-2细胞波形蛋白和α平滑肌肌动蛋白表达水平。结果萎缩和扩张的肾小管上皮细胞出现波形蛋白和α平滑肌肌动蛋白表达,肾组织中波形蛋白和α平滑肌肌动蛋白表达量显著增加;正常的HK-2细胞,细胞形态为不规则圆形,TGF-β1刺激后细胞伸展成长梭形;细胞α平滑肌肌动蛋白表达水平显著增加,波形蛋白表达水平无显著变化。结论体内实验研究上皮-间充质转分化,将波形蛋白作为间充质细胞标志物具有较好的参考价值,而体外研究中,其标志作用尚存在争议。  相似文献   
25.
 The S-locus-related gene SLR1 is highly conserved and highly expressed in several species of the Brassicaceae family. Its function has not been determined, although several features would suggest a fundamental role in pollination. A second related gene (SLR2) is conserved and expressed in a subset of Brassica genotypes. We analysed the stigmatic expression of SLR1 and SLR2 genes among 11 different plants from various species or genera of the Brassicaceae and examined the extent of the pollen-stigma interaction during intraspecific, interspecific and intergeneric pollinations between them. Appropriate statistical tests on these variables (pollen adhesion, germination, penetration into the stigma, style and ovary, and SLR gene expression) showed that expression of SLR1 (but not SLR2) may be a factor in pollen-stigma adhesion. This hypothesis was supported by the observation of reduced pollen-stigma adhesion in transgenic B. napus plants modified for SLR1 expression. Received: 25 February 1997/Revision accepted: 24 June 1997  相似文献   
26.
摘要 目的:探讨腰椎内镜下单侧入路椎板切除双侧减压术(LE-ULBD)与传统椎板间开窗技术椎管减压治疗退变性腰椎管狭窄症(DLSS)疗效及对JOA评分、ODI评分和关节活动度(ROM)的影响。方法:回顾性选取2019年11月-2022年4月收治的80例DLSS患者,根据手术方法分为研究组(n=40)和对照组(n=40),对照组采用传统椎板间开窗椎管减压术治疗,研究组采用LE-ULBD治疗,比较两组围手术期指标、腰痛和下肢痛的视觉模拟评分(VAS)、JOA评分、Oswestry评分、上下方邻近节段ROM。结果:研究组手术时间、住院时间短于对照组,切口长度小于对照组(t=3.249;t=3.240;t=16.690,P<0.05);术后1、3个月,研究组腰痛、下肢痛VAS评分低于对照组(t=2.296;t=2.071;t=2.531;t=2.117,P<0.05);术后1、3个月,研究组JOA评分高于对照组,ODI评分低于对照组(t=3.119;t=2.231;t=3.065;t=2.457,P<0.05);术后6个月,研究组上下方邻近节段ROM低于对照组(t=5.372;t=6.076,P<0.05);两组并发症比较,差异无统计学意义(P>0.05)。结论:相较于传统椎板间开窗椎管减压,LE-ULBD治疗DLSS能显著缩短手术时间和住院时间,减少手术创伤,保留上下邻近节段活动度,加快术后腰腿痛缓解及腰椎功能的恢复。  相似文献   
27.
Nicotiana tabacum was used as a pistillate parent and crossed with three self-compatible species, N. rustica, N. repanda and N. trigonophylla, which were previously reported to have pollen tubes unilaterally inhibited by N. tabacum pistil. Temporal and morphological observations revealed distinct differences of pollen tube behavior among these incongruous crosses. Pollen tubes of N. repanda were arrested in stigma and those of N. rustica in the middle of the style. On the other hand, pollen tubes of N. trigonophylla continued growing at a slow rate. Tubes of N. repanda and N. rustica showed morphological abnormalities such as swelling, thick wall, and irregular callose deposition. In addition, tubes of N. rustica often elongated in reverse direction and wound about in the middle of the style. Although the tubes of N. trigonophylla were apparently normal in morphology, they were distributed throughout the transmitting tissue, differing from the self-pollination of N. tabacum in which they were confined to the peripheral region of it. The diversity of pollen tube behavior indicates that physiological causes of incongruity are different among the three crosses. Bud pollination enabled pollen tubes to reach the ovary in all crosses, indicating that the N. tabacum pistil acquired its ability to inhibit foreign pollen tube elongation with its development. When interspecific hybrids between N. tabacum and the other three species were pollinated by parental species, tubes reached the ovary in all crosses, but the elongation rate of tubes slowed down and morphology was abnormal.  相似文献   
28.
Summary Pollen tube growth was evaluated using an 18-step scale after both intra- and interspecific pollinations of genotypically widely differing diploid potato species and potato dihaploids expressing monofactorial gametophytic incompatibility. The results obtained account for a wide array of types of pollen tube growth resulting from crossing partners with distinct incompatibility behavior. Based on the assumption that inhibition of pollen tubes is the rule and solely prevented by the pollen itself, a model proposing one common cause underlying different mechanisms for both intraspecific selfincompatibility and interspecific incompatibility in diploids is put forward. Data supporting the model are presented from the experimental results of this study and from the literature. The strength of pollen-style interaction depends on particular S-alleles in combination with recognition and activity properties of the basic S-genotypes. The model is suitable to explain all former observations on incompatibility in diploids with a gametophytic system of incompatibility and, with modifications of the manner of phenotypic expression, also in plants with sporophytic incompatibility. The proposed scheme of pollen tube growth phenotypes permits prediction of pollen tube growth behavior in an intended cross combination. The model is based on both classical Mendelian genetics and recent molecular genetic insight.  相似文献   
29.
In adult rats, removal of one ovary leads to an acute albeit transient rise in serum follicle stimulating hormone and an increase in the weight of the remaining ovary. In an attempt to correlate the high titre of endogenous follicle stimulating hormone with the changes taking place at the macromolecular level, the phenomenon of compensatory ovarian hypertrophy was studied for one cycle after hemiovariectomy at metoestrus in the adult, cycling female rats derived from the Holtzman strain. The significant finding with respect to hormonal changes was an acute follicle stimulating hormone surge commencing 6h post-unilateral ovariectomy, reaching a maximum at 12 h and declining thereafter, hitherto not reported in the Holtzman strain. Serum luteinizing hormone, prolactin, oestradiol-17β and testosterone remained unaltered while progesterone showed a decline at 6 h after surgery. There was an increase in the number of healthy class III (> 350 μm) follicles with a concomitant drop in atretic class III follicles 24 h post-unilateral ovariectomy. Analysis for DNA, RNA and protein content showed that all three constituents registered a continuous rise in the hypertrophying ovary up to 120h after surgery. When expressed as ?g/mg ovarian weight, the increase in DNA reached a maximum at 24 h and declined thereafter. The kinetics of DNA synthesis was followed by pulse labelling with [3H] thymidine at 18, 24, 36 and 48 h after unilateral ovariectomy. Maximum incorporation occurred at 36 h. Autoradiographic studies showed that the granulosa cells of healthy follicles preferentially incorporated the label. In an extension of this study, it was found that labelling index registered a significant increase following ovariectomy, the maximum being reached at 24 h especially in classIII follicles. The results clearly point out the crucial role of hyperplasia in the response of the contralateral ovary to the surgery and implicate the rise in follicle stimulating hormone as the primary signal for initiation of such a response. This raises the question whether in compensatory ovarian hypertrophy follicle stimulating hormone has a mitogenic role  相似文献   
30.
The pentose phosphate pathway operates at an elevated level in rat kidney following induction of diabetes and in the compensatory hypertrophy following unilateral nephrectomy in control and alloxan-diabetic rats, as shown by the yields of 14Co2 from [1-14C]glucose, [6-14C]glucose and 3H2O yields from [2-3H]glucose. The elevated flux through the pentose phosphate pathway is correlated with the increased RNA content and weight of the kidney. The direct utilization of NADPH for reductive synthetic reactions and the potential for indirect utilization via the sorbitol route and the linked transhydrogenase reactions of the glucuronate-xylulose pathway, for NADH and ATP generation, are also discussed.  相似文献   
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