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51.
陕西省健康人群脊髓灰质炎免疫屏障的评价 总被引:8,自引:2,他引:6
为了对陕西省近 10年脊髓灰质炎 (脊灰 )的免疫状况做出科学的评价 ,在地理特点不同、经济发展程度各异的 3个地区采集 0~ 39岁健康人群血标本 86 6份测定脊灰抗体。脊灰Ⅰ、Ⅱ、Ⅲ型中和抗体阳性率分别为96 88%、98 0 4%、92 73%,几何平均滴度 (GMT)分别为 1∶2 5 9 30、1∶10 3 6 9、1∶5 2 6 9。表明通过口服脊灰疫苗的常规免疫和强化免疫 ,陕西省健康人群对脊灰已形成牢固的免疫屏障。 相似文献
52.
W Y Chung C C Nast R B Ettenger G M Danoviton H J Ward A H Cohen 《Journal of the American Society of Nephrology : JASN》1992,2(8):1298-1301
Acquired cystic disease has been documented to complicate most forms of chronic renal damage; it has only infrequently been described in transplanted kidneys. Five patients with noncystic ESRD and chronically rejected transplants in which acquired cystic disease arose are reported. The diagnosis of acquired cystic disease was established in examination of transplant nephrectomies from four patients and a core biopsy from the fifth. The allografts were in place from 44 to 80 months; three patients were treated with hemodialysis before the diagnosis of acquired cystic disease, whereas two received peritoneal dialysis. Three of the four patients evaluated had cysts in the native kidneys. Although papillary hyperplasia of lining epithelium was evident in four specimens, only one kidney was the site of neoplasms in the form of multiple small tubular adenomas. No malignant neoplasms were noted in this study or in the few similar previous ones; however, it is possible that chronically rejected transplanted kidneys may harbor neoplasms with the same malignant potential as those in acquired cystic disease in native kidneys. 相似文献
53.
A finite element analysis was carried out to study the roles of posts in reducing dentin stress in pulpless teeth. Two-dimensional plane strain models of the midlabiolingual section of a human maxillary central incisor were first analyzed. The results showed that the gold alloy post reduced maximal dentin stress by as much as 30%. However, the integrity of the dentin was compromised and the effects of the post were likely to be exaggerated in such models. In an effort to correct for these problems, plane stress models with side plates and axisymmetric models were analyzed. Posts were found to reduce maximal dentin stress by only 3% to 8% when the teeth were subjected to masticatory and traumatic loadings in these latter models. Although posts reduced maximal dentin stress by as much as 20% when the teeth were loaded vertically, teeth such as incisors and canines normally are not subjected to vertical loadings. Thus the reinforcement effects of posts seem to be doubtful in these teeth. 相似文献
54.
We examine the relationship between ethnicity and income as determinants of mammography use over a span of four years as a means of assessing community intervention impacts. The sample consisted of 1,447 women older than 34 years, living in Hawaii, who participated in the Behavioral Risk Factor Surveillance System (BRFSS). The percentage of women in the sample reporting a screening mammogram within the past two years was 31.4% in 1987, 54.1% in 1989, and 51.6% in 1990. Women of Hawaiian ancestry had the lowest percentage of mammogram use in the past two years (38.7%), while Japanese women had the highest percentage (49.8%). Results of logistic regression analysis indicate a significant increase in mammography use from 1987 to 1989 and no difference from 1989 to 1990. Findings also showed an association between age, income, and ethnicity with use in the past two years. Greater age, higher income, and Japanese origin, compared to Hawaiian, were all independently associated with increased odds of having had a mammogram in the past two years. We discuss results in terms of program evaluation and future research implications for community health surveys. 相似文献
55.
The present study is a quantitative analysis of the unmyelinated fiber population in the fasciculus gracilis of the second cervical segment of cat and monkey. We find that unmyelinated fibers represent 13.7% of the total fiber population in this pathway in the cat and 18.9% in the monkey (Macaca fascicularis). The existence of such large numbers of these axons suggests that there may be a sizeable ascending fine primary afferent pathway in the fasciculus gracilis in cat and monkey whose destination is presumably the dorsal column nuclei. These findings are of interest in regard to classic ideas that the afferent fibers in the dorsal columns are large myelinated fibers that convey fine discriminative information to the dorsal column nuclei. 相似文献
56.
G. M. Brieger M. Mongelli L. Y. Hin T. K. H. Chung 《International urogynecology journal》1997,8(4):191-195
The epidemiology of urinary dysfunction in a Chinese population living in Hong Kong was investigated. Fifteen hundred ethnic
Chinese women answered a telephone questionnaire including symptoms of urinary dysfunction, anthropometric measurements, obstetric
history and place of birth. The relative predictive value of these factors was analyzed using logistic regression. The prevalence
of urinary dysfunction was 13%. Ten percent reported stress incontinence, and 4% had urgency or urge incontinence. The strongest
predictor was place of birth, with women born in mainland China having the highest prevalence of pure stress incontinence
(OR 1.33, CI 1.1–1.6). For the symptoms of detrusor instability age was the strongest predictor, with women over 50 years
being at greater risk (OR 2.8, CI 1.6–5.0). Contrary to earlier beliefs, urinary dysfunction in Chinese women is as common
as in Caucasian women. Place of birth is the strongest predictor for pure stress incontinence, with women born in mainland
China being at greater risk. This suggests that environmental factors in early life have a differential effect on the development
of urinary incontinence.
EDITORIAL COMMENT: Taiwan Chinese women have a comparable prevalence of urinary dysfunction with Hong Kong Chinese women.
A survey representing a multistage sample of 82 678 women aged 18 years or older was conducted in the Taipei area from January
to June 1993. A total of 818 cases were interviewed by trained students. One hundred and eighty-nine (23.1%) of the respondents
reported having had some degree of incontinence in the preceding 12 months, 28 (3.4%) reporting regular incontinence. Most
presented with stress urinary incontinence, whereas urge incontinence and mixed incontinence were more commonly seen in the
elderly group (aged 60 years or older). The risk factors for urinary incontinence included age, number of vaginal deliveries
(>3), number of abortions (>2) and maternal history of incontinence. Voiding symptoms (irritative or obstructive) and constipation
were significantly more prevalent among respondents with incontinence than those without (P<0.001). This evidence also indicates that the long-held belief that Chinese women have a much lower prevalence of urinary
dysfunction than western women has all but ended. 相似文献
57.
In this paper, we have derived some sufficient conditions for existence and uniqueness of equilibrium and global exponential stability in delayed Hopfield neural networks by using a different approach from the usually used one where the existence, uniqueness of equilibrium and stability are proved in two separate steps, rather we first prove global exponential convergence to 0 of the difference between any two solutions of the original neural networks, the existence and uniqueness of equilibrium is the direct results of this procedure. We obtain the conditions by suitable construction of Lyapunov functionals and estimation of derivates of the Lyapunov functionals by the well-known Young's inequality and Holder's inequality. The proposed conditions are related to p-norms of vector or matrix, p in [1, infinity] and thus unify and generalize some results in the literature. 相似文献
58.
Suk Hee Heo Yong Yeon Jeong Sang Soo Shin Tae Woong Chung Heoung Keun Kang 《Korean journal of radiology》2007,8(2):180-183
We report an uncommon case of solitary, small hepatic angiosarcoma that was initially considered as a hemangioma. We present the imaging findings, with an emphasis on the initial and follow-up CT and MR findings, as well as report on the more suggestive findings of angiosarcoma than those of a hemangioma. 相似文献
59.
Isolation of a renal function-facilitating constituent from the Oriental drug, salviae miltiorrhizae radix 总被引:2,自引:0,他引:2
An attempt was made to isolate the active component which exhibits an improving effect on renal function from Salviae Miltiorrhazae Radix (Chinese crude drug). Systematic isolation from aqueous extract of Salviae Miltiorrhizae Radix was carried out, and Compound 1 was found to be more effective than any of the other constituents in improving renal functional parameters; that is, a marked reduction of glomerular filtration rate following adenine ingestion was improved by administration of this substance. The renal plasma flow and renal blood flow were also increased in renal failure rats. On the basis of chemical and spectroscopic data, Compound 1 was shown to be identical with magnesium lithospermate B. 相似文献
60.
Pinhole collimator scintigraphy in differential diagnosis of metastasis, fracture, and infections of the spine 总被引:1,自引:0,他引:1
The informational gains obtained by the use of pinhole collimator scintigraphy (PCS) have been well documented. The present study has been undertaken to prospectively investigate its efficacy in diagnosing several commonly occurring spinal diseases. Patient material consisted of metastatic cancer (39 vertebrae), compression fractures (33 vertebrae), tuberculous spondylitis (17 vertebrae), and pyogenic spondylitis (six vertebrae). PCS findings were characterized in terms of localization, appearance, and homogeneity of abnormal radionuclide accumulation. Thus, metastatic cancer manifested as diffusely or focally homogeneous accumulation within the vertebral body or as a typical short-segmental accumulation along the end-plate, whereas compression fracture manifested as characteristic board-like accumulation along the entire length of end-plates. Tuberculous spondylitis, on the other hand, revealed homogeneous accumulation throughout the vertebral body, and pyogenic spondylitis revealed accumulation at the end-zone of opposing vertebral bodies giving sandwich-like appearance. The disk space at the affected level was not narrowed in the former two diseases but it was narrowed in the latter two. It was concluded that PCS may be useful in differentiating metastatic cancer, compression fracture, tuberculous spondylitis, and pyogenic spondylitis. 相似文献