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91.
早期脑血管病的微循环表现   总被引:1,自引:1,他引:1  
通过对血液微循环观测,分析微循环障碍与早期脑血管病发生率的相关性。方法:采用微循环显微镜观察人体甲襞微循环的微血管和微血流的动态变化。结果:微循环障碍患者,表现明显微血管痉挛性和淤滞性改变,由于微循环灌注减少,加重组织缺血缺氧,微血栓形成。结论:微血管及微血流的异常影响人体机能代谢的变化,导致微血管内皮损伤、血液的凝固性增强,而外周血流及血管的异常改变,同样可影响脑血流量及供血。提示微循环障碍与早期脑血管病密切相关。对早期预防、诊断具有重要参考价值。  相似文献   
92.
The clinical and radiological spectrum of spondylocostal dysostosis syndromes encompasses distinctive costo‐vertebral anomalies. RIPPLY2 biallelic pathogenic variants were described in two distinct cervical spine malformation syndromes: Klippel–Feil syndrome and posterior cervical spine malformation. RIPPLY2 is involved in the determination of rostro‐caudal polarity and somite patterning during development. To date, only four cases have been reported. The current report aims at further delineating the posterior malformation in three new patients. Three patients from two unrelated families underwent clinical and radiological examination through X‐ray, 3D computed tomography and brain magnetic resonance imaging. After informed consent was obtained, family‐based whole exome sequencing (WES) was performed. Complex vertebral segmentation defects in the cervico‐thoracic spine were observed in all patients. WES led to the identification of the homozygous splicing variant c.240‐4T>G in all subjects. This variant is predicted to result in aberrant splicing of Exon 4. The current report highlights a subtype of cervical spine malformation with major atlo‐axoidal malformation compromising spinal cord integrity. This distinctive mutation‐specific pattern of malformation differs from Klippel–Feil syndrome and broadens the current classification, defining a sub‐type of RIPPLY2‐related skeletal disorder. Of note, the phenotype of one patient overlaps with oculo‐auriculo‐vertebral spectrum disorder.  相似文献   
93.
A family with cardiac malformation, cleft lip-palate, short stature, microcephaly, distally placed thumbs, short 2nd and 5th fingers, long and broad 1st toes, broad distance between 1st and 2nd toes and mediodorsal curvature of the 4th toes with syndactyly of the 2nd and 3rd toes has been described as having a new syndrome. While some members of the family had full signs of the syndrome, others had similar but fewer and less severe anomalies of the same structures. The presence of common findings in three generations, its variable expressivity and pleiotropism, and the non-consanguineous history in the parents suggest that the inheritance is autosomal dominant.  相似文献   
94.
Lymphangioma is a disfiguring malformation of early childhood. A mouse lymphangioma model has been established by injecting Freund's incomplete adjuvant (FIA) intraperitoneally, but has not been compared with the human disease. We show that, in accordance with studies from the 1960s, the mouse model represents an oil-granuloma, made up of CD45-positive leukocytes and invaded by blood and lymph vessels. Several markers of lymphatic endothelial cells are expressed in both mouse and human, like CD31, Prox1, podoplanin, and Lyve-1. However, the human disease affects all parts of the lymphovascular tree. We observed convolutes of lymphatic capillaries, irregularly formed collectors with signs of disintegration, and large lymph cysts. We observed VEGFR-2 and -3 expression in both blood vessels and lymphatics of the patients, whereas in mouse VEGFR-2 was confined to activated blood vessels. The experimental mouse FIA model represents a vascularized oil-granuloma rather than a lymphangioma and reflects the complexity of human lymphangioma only partially.  相似文献   
95.
We describe a lethal malformation syndrome in 28 newborn infants from 18 families. The main manifestations were hydrocephalus (often with an unusual structure of the brain and the occipital bone), very small mandible, Polydactyly, congenital heart defect, abnormalities of the respiratory organs, and (different from the Meckel syndrome) normal kidneys. Polyhydramnios and stillbirth or neonatal death were the rule. Autosomal recessive inheritance is evident. This syndrome is another in the group of rare recessive disorders which are found in Finland. Because of the 25 % recurrence risk and possibilities for prenatal diagnosis, this syndrome should be recognized by paediatricians and, because of the frequent stillbirths, also by obstetricians and pathologists. The name hydrolethalus syndrome (hydramnios, hydrocephalus, lethality) may be of help in this.  相似文献   
96.
Isolated adducted thumbs is an uncommon malformation that occurs sporadically in the majority of cases although some affected families have been reported. Previously, autosomal dominant inheritance was suggested in two familial cases, but this mode of inheritance has not been confirmed. Here we describe a family with adducted thumbs and other digital anomalies in which seven members (six females and one male) are affected in three consecutive generations. Additionally, the patients showed mild abnormalities of fingers 2nd–4th bilaterally and hypoplasia of the middle phalanx of the 5th fingers. This family represents an autosomal dominant condition that apparently has not been previously reported.  相似文献   
97.
In this report we describe the occurrence of severe mesomelic shortening of the forearms due to hypoplasia of the ulnae with severe radial bowing. In contrast to the mesomelic dysplasias, i.e. Langer type of mesomelic dwarfism, this apparently autosomal dominantly inherited skeletal anomaly occurred as an isolated anomaly without concomitant involvement of shanks or other parts of the skeleton, and did not influence final adult height.  相似文献   
98.
Objective: The aims of the present study were to elucidate the interaction of reactive oxygen species (ROS) and Ca2+ response in central nervous system (CNS) pericytes. Methods: The intracellular Ca2+ concentration was measured using fluorescent Ca2+ indicator, fura-2, in cultured CNS pericytes. Results: Hydrogen peroxide evoked a dose-dependent increase in cytosolic Ca2+, which was completely inhibited by catalase. Removal of external Ca2+ or addition of nicardipine (1 μM) during application of hydrogen peroxide did not affect Ca2+ response. Incubation of the cells in Ca2+ free solution did not abolish but slightly reduced Ca2+ response by hydrogen peroxide. Ca2+ response to hydrogen peroxide was not altered by the depletion of intracellular Ca2+ by thapsigargin (1 μM). Pretreatment of the cells with tyrosine kinase inhibitor genistein (100 μM) or tyrphostin A47 (30 μM) significantly reduced Ca2+ increase by hydrogen peroxide. Conclusions: These results indicate that hydrogen peroxide evokes Ca2+ increase predominantly by release from intracellular Ca2+ store, which may be regulated by tyrosine kinases.  相似文献   
99.
We report a female patient who had a scalp hemangioma, a cleft uvula, an upper sternal defect, pectus excavatum, arachnodactyly, pes planus, and joint hypermobility. She had rupture of an aortic aneurysm after minor trauma at 11 years of age. At 17 years of age, elective repair of a dilated, ectatic aorta was complicated by cerebral ischemia. Other vascular abnormalities in the proband included an aneurysm of the left subclavian artery, atresia of the right carotid artery, and calcified cerebral aneurysms. We believe that the proband's physical anomalies are best described by the PHACE (posterior fossa brain malformations, hemangiomas, arterial anomalies, coarctation of the aorta and cardiac defects, and eye abnormalities) phenotypic spectrum. This spectrum of physical anomalies also includes sternal clefting and hemagiomas as part of the sternal malformation/vascular dysplasia (SM/VD) association, as found in our patient, and the acronym PHACES has also been used. We consider that the PHACE phenotypic spectrum is likely to be broader than previously recognized and includes orofacial clefting and aortic dilatation and rupture. Our patient also had skeletal anomalies that lead to consideration of Marfan syndrome as a diagnosis. It should be recognized that there is clinical overlap between PHACE syndrome and Marfan syndrome when aortic dilatation is present. We would also like to emphasize the minor nature of the cutaneous findings in our patient despite her severe vascular complications. This is in contrast to previous reports of large or multiple hemangiomas in PHACE syndrome. Published 2002 Wiley‐Liss, Inc.  相似文献   
100.
The results obtained in 304 consecutive patients with spontaneous subarachnoid hemorrhage are described, the majority of whom (86%) were admitted while in acute condition. Only 46% of the patients in this series were in good condition at admission. The initial management was standardized for all patients, but the protocol of "delayed surgery" was applied to patients with subarachnoid hemorrhage from aneurysmal rupture. Two hundred and twenty-two patients (73%) had intracranial aneurysms. Of these, 20 (9%) were moribund and died shortly after admission; nine (4%) underwent emergency surgery due to the coexistence of a life-threatening cerebral hematoma; seven (3%) were operated upon within 3 days of admission; 78 (35%) died after rebleeding or after steady deterioration of the patient's condition due to vasospasm while awaiting surgery. Of the remaining 108 patients ready for delayed surgery, 12 (11%) (operation refused, elderly patients in poor general condition, spontaneous thrombosis of the aneurysm) were treated conservatively, and 96 (89%), who were in various clinical conditions, were actually operated on. Of these 96 patients, 79 (82%) exhibited excellent or good results, 5 (5%) were disabled, and 12 (12%) died. In the authors' experience, the overall management of intracranial aneurysms in unselected patients according to the protocol of delayed surgery results in significant loss of patients awaiting surgery, and good surgical results in the survivors.  相似文献   
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