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71.
The records of an ongoing Health Surveillance Registry that utilizes multiple sources of ascertainment were used to study the incidence rate of infantile hypertrophic pyloric stenosis (IHPS) in liveborn children in British Columbia during the period 1966–1977 inclusive. The incidence was 4.6 males/1,000 livebirths and 1.2 females/1,000 livebirths, giving a male to female ratio of 3.1 to 1. No significant overall incidence variations with time could be shown during the study period. There was suggestive evidence of independent sex-incidence variation in different geographical regions, which clearly warrants further investigation. 相似文献
72.
Vio K Rodríguez S Navarrete EH Pérez-Fígares JM Jiménez AJ Rodríguez EM 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2000,135(1):41-52
Stenosis of the cerebral aqueduct seems to be a key event for the development of congenital hydrocephalus. The causes of such a stenosis are not well known. Overholser et al. in 1954 (Anat Rec 120:917-933) proposed the hypothesis that a dysfunction of the subcommissural organ (SCO) leads to aqueductal stenosis and congenital hydrocephalus. The SCO is a brain gland, located at the entrance of the cerebral aqueduct, that secretes glycoproteins into the cerebrospinal fluid that, upon release, assemble into a fibrous structure known as Reissner's fiber (RF). By the permanent addition of new molecules to its rostral end, RF grows and extends along the aqueduct, fourth ventricle, and central canal of the spinal cord. The immunological blockage of the SCO-RF complex has been used to test Overholser's hypothesis. The following was the sequence of events occurring in pregnant rats that had been immunized with RF glycoproteins: the mother produced anti-RF antibodies and transferred them to the fetus through the placenta and to the pup through the milk, and the antibodies reached the brain of the fetus and pup and blocked the SCO-RF complex. This resulted in a permanent absence of RF that was followed by stenosis of the cerebral aqueduct, and then by the appearance of hydrocephalus. The latter was patent until the end of the 6-month observation period. The chronic hydrocephalic state appeared, in turn, to induce new alterations of the SCO. It is concluded that a selective immunological knock out of the SCO-RF complex leads to hydrocephalus. 相似文献
73.
Ei Kawahara Yoshio Oda Shogo Katsuda Isao Nakanishi Kunihiko Aoyama Katsuro Tomita 《Virchows Archiv : an international journal of pathology》1991,419(5):373-380
Summary Thickened ligamenta flava obtained from 14 patients with spinal canal stenosis were examined with special reference to type VI collagen. The characteristic histological finding in the thickened area was rupture of normal elastic fibre meshwork with resultant fibrosis which usually appeared hyaline. Using an immunohistological method, collagen types VI, I and III were found to be present in the hyaline matrix. Ultrastructural study revealed many microfilamentous structures of type VI collagen admixed in loosely packed, banded collagen fibres. With differential salt precipitation of pepsin-extracted collagen the existence of type VI collagen was confirmed by SDS-polyacrylamide gel electrophoresis analysis and Western blotting analysis using anti-type VI collagen antibody. Quantification of type VI collagen in pepsin-extracted crude collagen samples by an inhibition enzyme-linked immunosorbent assay showed an increasing amount of type VI collagen in the thickened ligamenta flava compared to the normal ligaments. Thus, increase of type VI collagen is the main contribution to the thickening of the ligamentum flavum. This may represent an adaptational and reparative process associated with disruption of elastic fibres. 相似文献
74.
Robert H. Ardinger Kenneth K. Goertz Leone F. Mattioli 《American journal of medical genetics. Part A》1994,51(3):200-202
We report on a patient with Williams syndrome who suffered a cerebrovascular accident. Clinical evaluation demonstrated the presence of carotid and cerebral arterial stenoses. We believe these lesions led to acute cerebrovascular ischemia and a non-hemorrhagic cerebral infarction. It is possible the stenoses were exacerbated by a vasculitis. The stenoses were identified by both invasive and noninvasive imaging studies. These studies may have a role in the evaluation of persons with Williams syndrome. © 1994 Wiley-Liss, Inc. 相似文献
75.
We report an infant with Pfeiffer syndrome (acrocephalosyndactyly type V) and a solid cartilaginous trachea lacking rings. This airway abnormality has been reported in a child with Crouzon syndrome but has not been described in Pfeiffer syndrome. 相似文献
76.
作为文章[1]的继续,本文在文章[1]的分析结果基础上,针对壁面对称和非对称狭窄的两种不同情况,通过数值计算给出弯曲狭窄血管内血流的轴向和周向切应力的分布曲线,并讨论其随管壁面几何参数的变化情况。同时,还讨论壁面几何参数对平均血流量和压力降影响的规律。从中发现,当狭窄较轻时(λ<0.2),壁面切应力、平均流量和压力降受狭窄度(λ)的影响不大,而在狭窄较严重时(λ>0.7),狭窄度微小的变化会引起它们急剧变化。此外,在讨论狭窄的非对称性对上述血流动力学参数的影响时还发现,非对称性只对轴向切应力有明显的影响,而对其它参量的影响并不十分显著。 相似文献
77.
马尾神经根松弛症诊断及治疗研究 总被引:1,自引:0,他引:1
目的 :探讨马尾神经根松弛症的诊断及治疗。方法 :对我院开展椎管造影以来 ,发现马尾神经根松弛症9例患者的临床表现、椎管造影及治疗结果进行分析。结果 :9例患者除具有腰椎管狭窄症的一般临床表现之外 ,椎管造影结果显示狭窄节段上方马尾神经根呈波浪状蛇形卷曲 ,甚至“环状”改变 ,9例患者均行手术治疗。经随访 ,除1例患者症状无明显改善外 ,均完全恢复。结论 :椎管造影是诊断马尾神经根松弛症的有效手段 ,手术外围减压及神经根粘连松解是治疗的有效方法 相似文献
78.
79.
Honghong Ren Lijun Zhao Yutong Zou Yiting Wang Junlin Zhang Yucheng Wu Rui Zhang Tingli Wang Jiali Wang Yitao Zhu Ruikun Guo Huan Xu Lin Li Mark E. Cooper Fang Liu 《Renal failure》2021,43(1):477
AimsChronic kidney disease (CKD) and diabetes mellitus increase atherosclerotic cardiovascular diseases (ASCVD) risk. However, the association between renal outcome of diabetic kidney disease (DKD) and ASCVD risk is unclear.MethodsThis retrospective study enrolled 218 type 2 diabetic patients with biopsy-proven DKD, and without known cardiovascular diseases. Baseline characteristics were obtained and the 10-year ASCVD risk score was calculated using the Pooled Cohort Equation (PCE). Renal outcome was defined as progression to end-stage renal disease (ESRD). The association between ASCVD risk and renal function and outcome was analyzed with logistic regression and Cox analysis.ResultsAmong all patients, the median 10-year ASCVD risk score was 14.1%. The median of ASCVD risk score in CKD stage 1, 2, 3, and 4 was 10.9%, 12.3%, 16.5%, and 14.8%, respectively (p = 0.268). Compared with patients with lower ASCVD risk (<14.1%), those with higher ASCVD risk had lower eGFR, higher systolic blood pressure, and more severe renal interstitial inflammation. High ASCVD risk (>14.1%) was an independent indicator of renal dysfunction in multivariable-adjusted logistic analysis (OR, 3.997; 95%CI, 1.385–11.530; p = 0.010), though failed to be an independent risk factor for ESRD in patients with DKD in univariate and multivariate Cox analysis.ConclusionsDKD patients even in CKD stage 1 had comparable ASCVD risk score to patients in CKD stage 2, 3, and 4. Higher ASCVD risk indicated severe renal insufficiency, while no prognostic value of ASVCD risk for renal outcome was observed, which implied macroangiopathy and microangiopathy in patients with DKD were related, but relatively independent. 相似文献
80.
In the context of collateral circulation of the heart, the role of extra-cardiac collateral arteries has been thought to be negligible. We present a case in which such collateral vessel acted as a rescue, subsequent to a failed revascularisation attempt. With surgeons nowadays considering ‘less is more’ in terms of grafting in coronary artery bypass grafting (CABG), and more evidence arising in favour of medical therapy, we need to re-assess the role of these collateral vessels in the coronary circulation. 相似文献