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81.
82.
Ampullary organs of Acipenser naccarii sturgeons were examined by optical and electronic microscopy (transmission electron microscopy and scanning electron microscopy) from hatching until 1 month later when the juvenile phase is completely established. It was observed that, when A. naccarii begins to feed actively, the ultrastructural characteristics of ampullary organs already correspond to those of adult animals. These organs may, therefore, be functional and, together with taste buds, facilitate food search after exhaustion of yolk sac food reserves. Mature ampullary organs of A. naccarii are formed by an ampulla that communicates with the exterior by means of a short channel. These ampullae correspond to the sensory portion of these receptors and are formed by two cell types: receptor cells and support cells. Receptor cells present a kinocilium on their free surface and establish ribbon synapses with axon nerve endings that arise from the underlying conjunctive tissue. Support cells enclose receptor cells, bear stereocilia and occasional cilia, and are of a secretory nature. The mucus associated with ampullary organs mainly comprises neutral mucopolysaccharides, whereas mucopolysaccharides are usually acid in other fish groups. Anat Rec, 290:1178–1189, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   
83.
Summary The neurons of the medial terminal nucleus (MTN) of the accessory optic system (AOS) have been studied in the rat, rabbit and cat in Golgi-Cox and Golgi-Kopsch impregnated brain sections. The present anatomical findings permit a division of the MTN of these species into dorsal and ventral components (MTNd, MTNv), in agreement with other investigations. The MTNd contains predominantly linear-bipolar and linear-multipolar shaped neurons with cell bodies that measure in the range of 25–50 m. These neurons have 2 to 4 primary dendrites which, along with their smaller dendritic branches, are oriented in the plane of the long axis of the MTN (i.e. from ventromedial to dorsolateral). These linear-bipolar and linear-multipolar cells represent 70–80% of the neurons of the MTNd as seen in the Golgi impregnated sections. The remaining 20–30% of the MTNd neurons are nearly all multipolar in shape with somata measuring in the range of 15–25 m. An occasional multipolar neuron is larger, has a soma that measures around 30–60 m and has dendrites which extend outward from the cell body to cover large areas of the MTNd. There was considerable extension of the dendrites of MTNd neurons into the MTNv; however, the dendrites of MTNd neurons were not observed extending into the adjacent substantia nigra (SN) or ventral tegmental area (VTA) of Tsai (1925). Conversely, the dendrites of neurons in the neighboring SN and VTA course along the borders of the MTN but only occasionally extend into the MTN. The neuron population of the MTNv consists almost entirely of small-multipolar shaped cells with somata measuring from 15–25 m and dendritic trees resembling those described for multipolar cells of the MTNd. A small number of neurons of the ventral division are medium-multipolar in shape with cell bodies that measure approximately 30–60 m. Typically, these cells have several dendrites which extend ventrally within the MTNv and one or more dendrites that extend either across the MTNv or dorsally into the MTNd. Only a few linear-bipolar and linear-multipolar neurons were observed in the MTNv. The present findings are discussed in relation to anatomical, physiological, and histochemical studies on the MTN.Abbreviations to Figures CP Cerebral Peduncle - DTN Dorsal Terminal Nucleus - LG Lateral Geniculate Nucleus - LP Lateral Posterior Nucleus - MG Medial Geniculate Nucleus - ML Medial Lemniscus - MTNd Medial Terminal Nucleus, dorsal division - MTNv Medial Terminal Nucleus, ventral division - NTO Nucleus of the Optic Tract - PA Anterior Pretectal Nucleus - pn Nucleus Paranigralis - PP Posterior Pretectal Nucleus - Pul Pulvinar - PO Olivary Pretectal Nucleus - RN Red Nucleus - SGS Stratum Griseum Superficiale, Superior Colliculus - SN Substantia Nigra Supported by USPHS research grant EYO3642 from the National Eye Institute  相似文献   
84.
目的:探讨骨盆环恶性肿瘤的切除、重建方式与并发症的处理 .方法:手术治疗骨盆环原发恶性或低度恶性肿瘤5例,其中骶骨恶性畸胎瘤2例、脊索瘤1例,髂骨骨肉瘤1例、恶性骨软骨瘤1例.所有患者术前未行动脉栓塞、结扎髂内血管.髂骨翼肿瘤采用自体髂骨、髋臼肿瘤采用异体骨重建骨盆环、自体股骨头重建髋臼骨床 人工全髋关节置换术.结果:5例肿瘤均行根治性切除,3例骶骨肿瘤术中出血量150~800 mL,术后出血300~1 000 mL,1例切口感染,1例术后出现失血性休克.髂骨翼肿瘤和髋臼周围肿瘤术中出血量分别为1 000 mL和4 000 mL,术后分别为800 mL和1 100 mL.髂骨肿瘤切除与重建患者2月后恢复关节功能,髋臼肿瘤切除与重建患者6月后恢复功能,4例患者术后随访4~24个月,生存良好.结论:骨盆环恶性肿瘤的外科手术治疗关键是完整的手术切除,包膜外切除可以减少出血、预防复发,影响骨盆环稳定时应考虑重建,自体、异体骨移植能够恢复髋臼周围骨量、维持骨盆环生物学稳定.  相似文献   
85.
Predictive value of normal sperm morphology: a structured literature review   总被引:12,自引:0,他引:12  
The aim of the study was to conduct a structured review of theliterature published on the use of normal sperm morphology,as an indicator of male fertility potential in the in-vitrofertilization (IVF) situation, and to establish the universalpredictive value of this semen parameter. Published literaturein which normal sperm morphology was used to predict fertilizationand pregnancy, during the period 1978-1996, was reviewed. Atotal of 216 articles were identified by the sourcing methodology,but only 49 provided data that could be tabulated and analysed.Of these, only 18 provided sufficient data for statistical analysis.Fifteen studies used the strict criteria to evaluate sperm morphology,two used World Health Organization (WHO) guidelines and oneused both the strict criteria and the WHO guidelines. All thestudies (n=10) using the 5 and 14% normal sperm morphology thresholds(strict criteria) produced positive predictive values for IVFsuccess. In the prediction of pregnancy, 82% (9/11) and 75%(6/8) of the studies produced positive predictive values whenusing the 5% and 14% thresholds respectively. Aggregating thedata produced around the 5% normal sperm morphology threshold(strict criteria), the overall fertilization rates were 59.3%(1979/3337; per oocyte) for the 4% group and 77.6% (10345/13327;per oocyte) for the >4% group, and the overall pregnancyrates were 15.2% (60/395; per cycle) and 26.0% (355/1368; percycle) respectively. The no-transfer rates across the 5% thresholdwere 24.0% (86/359; per cycle) in the 4% group compared to 7.4%(80/1088; per cycle) in the >4% group. The inclusion of anaccurately evaluated normal sperm morphology count as an integralpart of the standard semen analysis makes this analysis stillthe most cost-effective means of evaluating the male factor.  相似文献   
86.
The discharge characteristics of sacral visceral afferents supplying the urinary bladder, urethra, colon and anus to mechanical stimuli were analyzed in the anaesthetized cat. The stimuli used were passive distension (urinary bladder, colon), isovolumetric contraction (urinary bladder), movements of the urethral catheter and mechanical shearing stimuli (mucosal skin of the anal canal). (1) In total 245 afferent units which projected in the pelvic nerve were isolated from the sacral dorsal roots. From one of the following organs, urinary bladder, colon, urethra and anus 117 afferent units were activated. By these stimuli from the bladder, urethra and anus 122 afferent units could not be activated, and as far as tested also not from the colon; in 6 afferent units the classification was unclear. (2) Afferent units from the urinary bladder and the colon responded consistently to passive distension of the respective organ. The units from the urinary bladder showed graded responses at intraluminal pressures of about 10–70 mm Hg and responded also to isovolumetric contractions of the organ. The thresholds of the units from the bladder to passive distension and contraction varied from about 5 to 20 mm Hg intravesical pressure. (3) The afferent units from the urethra and the anus did not react or showed some weak phasic and irregular responses to distension and contraction applied to the urinary bladder or to distension of the colon. They were consistently excited by low threshold mechanical stimulation of the urethra and anus, respectively. (4) The axons from the bladder, urethra and anus were presumably myelinated (conduction velocity above 2 m/s) and conducted at 10.3±6.1 m/s (n=34, mean±SD), 26.3±9.3 m/s (n=13) and 9.5±5.1 m/s (n=37), respectively. The axons from the colon conducted at about 0.5 to 16 m/s (n=20), 13 of them conducting at less than 2 m/s. About 75% of the axons which could not be activated by mechanical stimulation of the visceral organs were presumably unmyelinated (conduction velocity below 2 m/s). (5) Some ongoing activity was found in 9 out of 26 afferent units from the anus but, with one exception, the afferent units from the bladder, urethra and colon were silent. (6) It is concluded that the pelvic afferent units from the urinary bladder, urethra, colon and anus consist of distinct populations with characteristic response patterns. There is no indication from this investigation that the urinary bladder is supplied by sacral afferents which are only recruited at high intravesical pressures during passive distension and isovolumetric contractions and which are possibly associated with pain.Supported by the Deutsche Forschungsgemeinschaft  相似文献   
87.
乳腺叶状肿瘤的形态学和免疫组织化学研究   总被引:1,自引:0,他引:1  
目的观察乳腺叶状肿瘤(phyllodes tumours,PTs)的形态学和免疫组织化学特征,并探讨其诊断标准。方法对21例PTs进行组织学观察和免疫组化SP法检测,并选取5例乳腺纤维腺瘤和5例乳腺腺病标本作为对照组。使用一抗包括CK-pan、EMA、SMA、p53、S-100蛋白、CD117、CD34、CD99、bc l-2、ER、PR、K i-67、CD10。结果21例PTs大体上均表现为界限清楚的肿块,且呈分叶状。肿瘤由具有双层排列的上皮成分以及过度生长的间质成分组成。根据间质的过度生长程度、细胞的异型程度、核分裂数、肿瘤边缘情况、有无异源性成分以及肿瘤性坏死等继发性改变将其分为良性、交界性和恶性3个级别。间质细胞免疫组化表达情况:CKpan:0/21、EMA:0/21、SMA:17/21、CD117:6/21、CD34:18/21、S-100蛋白:2/21、CD99:13/21、CD10:8/21、PR:5/21、ER:4/21、p53:18/21、K i-67:3%~10%、bc l-2:15/21。结论PTs的诊断主要依据组织学观察,免疫组化CD117、CD34、CD99、CD10、bc l-2的检测可以起到一定的辅助作用。  相似文献   
88.
Increased adrenal cortical activity and hypertrophy of adrenal glands associated with defeat and social subordination have been reported frequently in small mammals; these adrenal changes have been linked to impairments in immune response, glucose metabolism and reproductive performance. Similar studies in primates have produced variable results. The current study was undertaken to illuminate the effects of social status on the adrenal gland and to examine concurrent effects of social variables on other physiological systems in Macaca fascicularis, in an initial exploration of the hypothesis that high and low social status have different physiological consequences. Sixty adult male M. fascicularis were housed in social groups of n = 5, under either stable or unstable social conditions. It was found that subordinate animals had heavier adrenal glands and somewhat higher plasma glucose concentrations than dominants. In contrast, dominants had higher blood pressure and worsened atherosclerosis, under some conditions, than subordinates. These data appear to offer preliminary support for Henry and Stephen's hypothesis of differential arousal of dominant and subordinate animals.  相似文献   
89.
K Sosa  A Mori  M Sisido  Y Imanishi 《Biomaterials》1985,6(5):312-324
Prepolymers, which were produced by the polyaddition reaction of polytetramethylene glycol (PTMG) or polyethylene glycol (PEG) and 4,4'-diphenylmethane diisocyanate (MDI) or hexamethylene diisocyanate (HMDI), were chain-extended with a linear dipeptide of L-serine (Z-Ser-Ser-OMe) or a cyclic dipeptide of L-serine [c-(Ser)2] to yield novel polyetherurethanes containing dipeptide segments. The relationship between the surface morphology and the biomedical properties of the film of the novel polyetherurethanes was investigated. The surface of PU(PTMG,Z-Ser-Ser-OMe,MDI) film was smooth, but fibrous structures were developed in the bulk of the film with increasing molecular weight of the PTMG segment. The antithrombogenicity of the film containing the low molecular weight PTMG segment was better than that of the usual polyetherurethane film without the dipeptide segments. The partial hydrolysis of the ester groups involved in the dipeptide segment improved the antithrombogenicity. In the surface and the bulk of PU[PTMG,c-(Ser)2,MDI] film, spherulite structures were developed when the molecular weight of the PTMG segment was high, while single crystals with a length of 3-4 microns were produced when the molecular weight of the PTMG segment was low. The antithrombogenicity of the film containing the high molecular weight PTMG segment was better than that of the usual polyetherurethane film without the dipeptide segments. PU(PTMG/PEG,Z-Ser-Ser-OMe,MDI) film and PU[PTMG/PEG,c-(Ser)2,MDI] film were permeated by uraemic toxins. The permeation was accelerated with increasing water content of the film and decreasing molecular weight of the solute. The oxygen permeability of the film of the polyetherurethane containing the linear or cyclic dipeptide segments was greater than that of polyetherurethane film which does not contain the dipeptide segments.  相似文献   
90.
狗冠状动脉的几何形态学   总被引:5,自引:0,他引:5  
本文采用8例成年狗心,其中5例制成冠状动脉铸型;3例制备血管墨汁灌注的组织切片,测量左、右冠状动脉的分支共1525个。应用Stfahler体系分级方法。对冠状动脉的分支用计算机进行分级归类、分析处理。求得左、右冠状动脉各级分支的一系列几何形态数据以及相应的直径比、长度比和分支比。冠状动脉的直径、长度及分支数目与分支级数呈指致函数关系,其相关有高度显著性(P<0.005)。从几何形态学的定量角度,探讨了狗左、右冠状动脉的形态特征,认为左冠状动脉是狗心首要的供血动脉。  相似文献   
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