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排序方式: 共有428条查询结果,搜索用时 15 毫秒
191.
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HF Rodgers CM Irvine IL van Wezel TC Lavranos MR Luck Y Sado Y Ninomiya RJ Rodgers 《Canadian Metallurgical Quarterly》1998,59(6):1334-1341
During follicular development the proliferative and differentiated state of the epithelioid granulosa cells changes, and the movement of fluid across the follicular basal lamina enables the formation of an antrum. Type IV collagen is an important component of many basal laminae. Each molecule is composed of three alpha chains; however, six different type IV collagen chains have been identified. It is not known which of these chains are present in the follicular basal lamina and whether the type IV collagen composition of the basal lamina changes during follicular development. Therefore, we immunolocalized each of the six chains in bovine ovaries using antibodies directed to the nonconserved non-collagenous (NC) domains. Additionally, dissected follicles were digested with collagenase to release the NC domains, and the NC1 domains were then detected by standard Western immunoblot methods. The follicular basal lamina of almost all primordial and preantral follicles was positive for all type IV collagen alpha chains. Colocalization of type IV collagen and factor VIII-related antigen allowed for discrimination between the follicular and endothelial basal laminae. Type IV collagen alpha1, alpha2, alpha3, alpha4, and alpha5 chains were present within the follicular basal lamina of only a proportion of antral follicles (17 of 22, 20 of 21, 15 of 18, 14 of 28, and 12 of 23, respectively), and staining was less intense than in the preantral follicles. Staining for the alpha1 and alpha2 chains was diffusely distributed throughout the theca in regions not associated with recognized basal laminae. The specificity of this immunostaining for alpha1 and alpha2 chains of type IV collagen was confirmed by Western immunoblots. As well as being detected in the basal lamina of approximately half of the antral follicles examined, type IV collagen alpha4 also colocalized with 3beta-hydroxysteroid dehydrogenase-immunopositive cells in the theca interna. Type IV collagen alpha6 was detected in the basal lamina of only one of the 16 antral follicles examined. Thus, the follicular basal lamina changes in composition during follicular development, with immunostaining levels being reduced for all type IV collagen chains and immunoreactivity for type IV collagen alpha6 being lost as follicle size increases. Additionally, immunoreactivity for alpha1 and alpha2 appears in the extracellular matrix of the theca as it develops. 相似文献
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YM Lo ES Lo N Watson L Noakes IL Sargent B Thilaganathan JS Wainscoat 《Canadian Metallurgical Quarterly》1996,88(11):4390-4395
The bilateral trafficking of nucleated cells between the fetus and the mother was studied using polymerase chain reaction (PCR)-based systems sensitive enough to detect 1 target cell in 100,000 background cells. Sixty-six mother-baby pairs were recruited; maternal and cord blood samples were collected at delivery for DNA extraction. Cell trafficking was studied in informative cases using PCR-genotyping of polymorphic regions in the beta-globin cluster, the glutathione S-transferase M1 locus and the angiotensin converting enzyme gene. In addition, Y-PCR was also used in conjunction with these systems for the detection of fetal cells in maternal circulation. Fetal cells were detected in maternal peripheral blood in 26 of 51 cases whereas maternal cells were detected in 16 of 38 fetal umbilical cord blood samples. The proportion of umbilical samples with detectable maternal sequences was much higher than previously reported. In the 28 cases informative for both mother and baby, there was no obvious correlation between the cell traffic from mother to baby as compared to that from baby to mother. These findings may have implications for the use of cord blood for bone marrow transplantation, the vertical transmission of infectious agents, and the physiology of the feto-maternal relationship. 相似文献
196.
SL Dzemeshkevich AS Ivanov IE Rykunov LM Kuznetsova NA Trekova IV Poplavski? AE Belous IL Zhidkov Kh Koseros AA Eremenko NI Chaus 《Canadian Metallurgical Quarterly》1998,(6):49-53
Standard technique of establishment of interatrial anastomoses allows to carry out orthotopic transplantation of the heart quickly and reliably. However the accumulation of collective experience evidences about a number of unavoidable shortcomings of such operation: rhythm disturbances, worsening of hemodynamics in discordant atrial contractions of recipient and donor, atrio-ventricular valve insufficiency, thromboembolism, coronary fistulas. Since 1990 in RRCS 25 operations were carried out with the use of standard technique and we also met with the risk of developing the above complications. In experiment on 30 mongrel dogs the technique of anatomical, truly orthotopic transplantation of the heart with six anastomoses was developed: left pulmonary veins with a common cuff, separate anastomoses of the superior and inferior caval veins, anastomoses of aorta and pulmonary artery. Particular attention was paid to developing of original surgical modes for prophylaxis of stenoses in the area of anastomoses of pulmonary and caval veins. In 1997 the anatomical technique of heart transplantation was successfully introduced by us into clinical practice. Clinical electrophysiological, echocardiographic and functional examinations have confirmed the results of the experiments and have evidenced for substantial advantages of the anatomical technique of orthotopic transplantation of the heart. By reliability the new operation is not inferior to standard method of N. Shumway. 相似文献
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The lactate dehydrogenase isoenzyme patterns in 46 extraocular eye muscle samples removed at surgery for squint were determined by acrylamide-gel electrophoresis and reduction of NAD coupled with formazan reaction. Muscle type subunits predominated in the isoenzymes of the medial and lateral rectus muscles of emmetropic and hypermetropic eyes, whereas heart type subunits predominated in those of myopic eyes. 相似文献
199.
We report our experience with epidural morphine analgesia. Morphine 2-3 mg in 10-15 ml 0.9% saline was given to patients after abdominal surgery, patients with terminal carcinoma and patients with multiple fractured ribs. Mean duration of analgesia was 14 hours and was not accompanied by severe complications. 相似文献
200.