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971.
自然是园林的主体--朱有玠大师园林设计思想和实践 总被引:1,自引:0,他引:1
文章介绍了未有玠大师的园林设计思想:立意是设计的灵魂,传统文化是设计的底蕴,体宜因借是中国园林设计的手法精髓.对其具有代表性的主题园林的表现手法、创作特征作了剖析和介绍,并以南京药物园和红楼艺文苑为例,对"自然是园林的主体"作了进一步的分析介绍. 相似文献
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To obtain accurate, unbiased rates of neural tube defects (NTDs) in twins, we conducted a population-based study that included live births and fetal deaths in Los Angeles County, California, ascertaining cases by multiple methods. Twenty-eight twin cases yielded a prevalence-at-birth of 1.6/1,000 twin births, which is significantly higher than the singleton prevalence of 1.1/1,000 births. In twins compared with singletons, the prevalences of both encephalocele and anencephaly are increased, whereas spina bifida is decreased. The twin case male/female sex ratio (.55) is lower than the singleton case sex ratio (.77). Concordance is relatively low at 3.7%, but appears to be higher than recently reported recurrence risks in other low prevalence areas. Stillbirths were most common among female cases and like-sex twins. Our study tends to support proposed etiologic theories associating NTDs with females or monozygotic twins, or both. There is increasing evidence that the etiology of NTDs may differ in high and low prevalence areas. We suggest also that twins and singletons may differ in their response to etiologic factors. The variations among anencephaly, spina bifida, and encephalocele in their association with twinning suggest that there may be different factors that influence the development of each specific NTD. The noted differences among the malformations also indicate that some of the variation among results of other studies of NTDs and twinning may be due to case ascertainment. Including spina bifida cases would decrease the proportion of twins in a study population, while including anencephalics would increase the proportion. Importantly, ascertaining fetal deaths would increase the proportion of anencephalics and case females, so studies of NTDs that do not include fetal deaths will show fewer twins than expected. On the basis of our findings and those of Layde et al., excluding encephaloceles will also decrease the number of twins among NTD cases. When investigating etiologic hypotheses for NTDs, these potential biases must be recognized. 相似文献
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The gene frequencies in samples of two language groups from Afghanistan, comprising 104 Pushtu and 179 Dari subjects living in Kabul, have been examined for 24 loci. Some systems suggest greater affinity to the west (e.g. the MS gene combination, the esterase D2 allele), some to the east (e.g. the K blood group), while others are intermediate between those of India and the Orient on the one hand, and Europe and the West on the other. In general, the gene frequency levels are much as would be expected from the geographical position of the country. The two language samples are essentially similar in gene frequency, so any earlier gene frequency differences that may have existed between the language groups are no longer distinguishable. However, the amount of heterozygosity shows that the Kabul population is not yet homogeneous and that the two endogamous linguistic groups remain disparate to some extent. 相似文献
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BJ Cedermark LE Blumenson JW Pickren DE Holyoke EG Elias 《Canadian Metallurgical Quarterly》1977,144(4):537-546
A study to determine the frequency of metastases to the adrenal glands following carcinoma of the colon and rectum was undertaken. Patients with, or without, adrenal spread were compared regarding age, sex, race and survival time. The over-all metastatic pattern was analyzed to determine its usefulness for predicting the presence of metastases to the adrenal glands. Autopsy reports and clinical records of patients with adrenal spread were reviewed regarding the extent of tumor involvement in the glands and possible adrenal insufficiency. Of 457 patients with adenocarcinoma of the colon and rectum who underwent autopsy, 63 or 14% had metastasis to the adrenal glands. Of these, 29 had bilateral involvement. Patients with bilateral metastases had a lower median age than did those without adrenal spread. No correlation was found between adrenal metastatic status and sex or race. Although survival time was found to be shorter for patients with bilateral metastases of the adrenal glands, adrenal insufficiency did not seem to be the reason for this shorter survival time. In retrospect, however, the presence of adrenal insufficiency could not be ruled out in several of these patients. Eight sites were studied with regard to whether or not metastatic involvement in a specific site might indicate a higher risk for simultaneous metastases to the adrenal glands. It was found for all sites that, when involved, there was a higher frequency of metastases to the adrenals than if free of tumor. Metastases especially above the diaphragm indicated a considerable risk for adrenal involvement. Different sites were combined in groups and studied in the same way. It was found that the more sites involved, the higher the relative chance of metastases to the adrenals. It was suggested that the results presented may be useful in predicting the relative chance of adrenal metastases in patients with advanced carcinoma of the colon and rectum. 相似文献
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