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71.
脉络膜黑色素瘤脱色素处理后Caspase-3的免疫组化研究   总被引:4,自引:0,他引:4  
目的 观察凋亡基因Caspase-3在脉络膜黑色素瘤(choroidal melanoma)中的表达及分型与细胞凋亡的关系。方法 收集20例脉络膜黑色素瘤标本,对其进行Caspase-3免疫组织化学染色,观察表达情况及染色强度。结果 Caspase-3在脉络膜黑色素瘤有较好的表达,在梭形细胞型中5例/6例呈阳性表达,在混合型中6例/8例呈阳性表达,在上皮样瘤细胞型中3例/4例呈阳性表达,在坏死型中1例/2例呈阳性表达,且在各型之间没有显著性差异(P>0.05)。结论 凋亡在脉络膜黑色素瘤中存在;Caspase-3在脉络膜黑色素瘤的发生发展中起重要作用。  相似文献   
72.
本文分析了20例PNH患者红细胞膜总脂,Ch/PIM比及磷脂组分,并比较了10例PNH红细胞膜AChE在PBS系统和生理盐水中的酶活性。发现PNH红细胞膜脂缺失严重,比正常少22%,但Ch/PIM比值及各磷脂相对含量均无明显改变。在PBS中AChE活性接近正常红细胞,但在生理盐水中明显低于正常红细胞,仅为正常的40%。表明PNH红细胞对补体敏感而溶血可能是由于补体导致膜脂缺失,进而破坏了红细胞膜结构的完整性而引起的,这也是AChE活性在低pH环境中酶活性比正常红细胞低的原因。  相似文献   
73.
研究结果表明:①人鼻粘膜的上皮在胚胎期的发育并不完善。在新生儿,纤毛上皮细胞的融合刚刚开始,其表面的纤毛呈微绒毛状。②在最常见的四种鼻粘膜炎症病变中,其超微结构的损害程度以伴有化脓性感染者最重,慢性肥厚性鼻炎与萎缩性鼻炎次之,变态反应性鼻炎最轻。③上述四种炎症病人的鼻纤毛输送能力均较正常人差,其中以伴有化脓性感染者最差,慢性肥厚性鼻炎和萎缩性鼻炎次之,变态反应性鼻炎最轻。  相似文献   
74.
Eight premature babies affected by hyaline membrane disease and needing mechanical respiratory support were ventilated by means of a VDR 1 (Bird Space Technology) respirator at 10 Hz during a mean time of 51 h. Before HFV 7 infants had been on conventional mechanical ventilation (CMV) and one on nasal CPAP. The values of mean airway pressure (MAP) and oxygenation index (PaO2/FIO2) on CMV and HFV were (mean and range): 1. CMV: MAP 15 (4–29) mm Hg, ox. index 15.47 (5.07–23.19) kPa; 2. HFV after 1 h: MAP 15 (10–19) mm Hg, ox. index 24.13 (9.07–46.12) kPa. Improved oxygenation allowed rapid reduction of FIO2 in the following hours. Only 3 infants were weaned directly from VDR 1, 5 were switched back to CMV mainly because of technical failures of the respirator. The change from HFV to CMV was associated with a fall of PaO2/FIO2 from 35.99 (15.86–74.52) to 22.39 (7.33–31.46) kPa. The mean time of artificial ventilation (CMV+HFV) was 121 h (range 46–166). Except for 1 pneumothorax no medical complications were seen during HFV, and all patients survived. Despite impressive improvements in oxygenation it is cautioned against the use of the VDR 1 because of the high incidence of technical problems.  相似文献   
75.
The major forms of lung pathology in the perinatal period are reviewed with emphasis on disturbances of growth and maturation. Lung hypoplasia results from impairment in the physiological control of lung growth during the fetal period. It is more common than organogenetic defects which are discussed only briefly. Hyaline membrane disease is now seldom seen in a pure form due to improvements in perinatal care. However, its complications and sequelae such as interstitial emphysema, pneumothorax and bronchopulmonary dysplasia are encountered more frequently. In addition, a wide variety of pathological processes may localize to, or be expressed in, the lung of the newborn, notably asphyxial changes, persistent pulmonary hypertension, haemorrhage and infection.  相似文献   
76.
Two-dimensional HOHAHA and ROESY nuclear magnetic resonance techniques are used to obtain complete proton resonance assignments and to perform a conformational investigation of the neuropeptide neurotensin (pGlu-Leu-Tyr-Glu-Asn-Lys-Pro-Arg-Arg-Pro-Tyr-Ile-Leu) in aqueous solution, methanol, and membrane-mimetic [deuterated sodium dodecylsulfate (SDS)] environments. Results suggest the absence of discernible elements of secondary structure in water and methanol. ROESY spectra confirm that Lys-Pro and Arg-Pro peptide bonds are all-trans, but that a significant population of cis Arg-Pro bonds arises in aqueous solution, which increases in the environment of SDS micelles. The conformational ensemble of the peptide is observed to narrow as it becomes bound through its cationic mid-region to SDS micelles, with the accompanying advent of local extended structure. The overall results indicate the inherent conformational flexibility of neurotensin, and emphasize the environmental dependence of conformation in peptides of medium length.  相似文献   
77.
Membrane flow within the myelin sheath in IDPN neuropathy   总被引:1,自引:0,他引:1  
This report describes some aspects of beta,beta'-iminodipropionitrile (IDPN) neuropathy in rats as observed by ultrastructural methods and X-ray diffraction. Light microscopy shows gross swelling of the axons in proximal lumbar spinal roots 8 days after intraperitoneal injection of IDPN. Mean axon cross-sectional area and mean axon perimeter increased to 280% and 160% of their control values, respectively. At the same time, myelin membrane packing was not visibly disturbed. In addition, X-ray diffraction patterns, recorded under physiological conditions, demonstrate that the myelin lipid bilayer thickness and widths of the aqueous spaces between bilayers did not change. Related observations are made on posterior tibial nerve (PNS myelin) and ventral spinal cord (CNS myelin). The various observations together are interpreted in terms of a fluid myelin membrane. It is proposed that the myelin membrane flows during axon swelling even though normal membrane-membrane contacts are maintained within the sheath. Membrane flow and slippage between membranes are explained in terms of a molecular model of the myelin multilayer.  相似文献   
78.
Summary. The aim of the present study was to establish a more differentiating indicator of plasma membrane integrity of spermatozoa than the classic version of the hypoosmotic swelling test according to Jeyendraan. Spermatozoa were prepared by density gradient centrifugation (90% Percoll) to select 'fertilization competent' spermatozoa only. After a second washing procedure sufficiently pure sperm cell suspensions were obtained. The volume distributions of these sperm cells were measured with a Coulter Counter at 25 °C after adaptation in 300 mosmolar NaCl solution resp. 150 mosmolar NaCl solution for 5 min. These volume distributions showed significantly different patterns for the isotonic and hypotonic stress situation in the simple salt solution. Moreover, the comparison of the response to hypoosmotic stress showed more than four reproducible characteristic patterns, promising well differentiated results for different sperm populations. The new method for the detection of hypoosmotic swelling effect might be a real and valuable functional parameter.  相似文献   
79.
80.
Summary Effects of Chinese Medicinal Preparation “Re Du Qing” (RDQ) on the activation, proliferation and membrane fluidity of T lymphocytes from human peripheral blood Were studied by means of3H-TdR incorporation and DPH fluorescence polarization. The results showed that “RDQ” can:1) significantly inhibit the activation of T lymphocytes; 2) restrain the proliferation of activated T lymphoblasts in the presence of exogenous interleukin-2 (IL-2); and 3) increase the membrane fluidity of T lymphocytes and antagonize the decreased fluidity of lymphocyte membrane mediated by Con A or PHA. The functional abnormalities of T lymphocytes in some autoimmune diseases such as arthritis and the usefulness of RDQ in the treatment of these diseases were also discussed.  相似文献   
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