Gonadoblastoma: histologic, ultrastructural, and histochemical observations in five cases

In this series of gonadoblastomas it appeared that the germ cells were the motivating force underlying either tumor proliferation or regression. The ultrastructural morphology confirmed the presence of undifferentiated gonadal cells with active steroid synthesis by the interstitial cells. The Call-Exner-like bodies which showed extensive calcification were composed of basement membrane material containing a sulfated mucosubstance. A histochemical comparison with the noncalcifying Call-Exner bodies of a granulosa-cell tumor differed only in their glycoprotein content. The calcium deposits were identified as oriented hydroxyapatite crystals by electron diffraction, and it is proposed that the basement membrane material serves as a nucleation site for calcification. High serum testosterone levels were correlated with the presence solely of interstitial cells in one case. The finding of a gonadoblastoma without the presence of a Y chromosome contradicts earlier proposals concerning the requirement of a Y chromosome for germ cell proliferation.     

Diffraction from a Natural Grain Boundary in a Magnetite Bicrystal

The structure of a natural small-angle boundary in a magnetite bicrystal was investigated by X-ray diffraction. This boundary was a "general" type with a mixed twist and tilt character. The grain-boundary reflections observed around an 040 matrix reflection were in good agreement with those predicted by Boll-mann's O-lattice theory. These extra reflections appear to arise from a predominantly planar dislocation network. The structural width of the boundary, determined from the length of the relrods of the grain-boundary reflections, was of the order of four unit cells, close to the average spacing of the expected dislocation network.     

量度及預測隧道鑽機的土傳噪音及震動

在市區進行夜間隧道鑽挖工程所產生的土傳噪音及震動,容易引起投訴。現時的技術難以準確預測噪音及震動的級數,而隧道工程的進度也常因進行隧道鑽挖工程時產生過大的土傳噪音及震動而延誤。本文所提述的新技術,可以更準確地量度及預測鑽機震動強度及土壤傳震的特性@個技術包括測量單位衝擊力及隧道鑽機摩擦力所產生的震動級數鋵嵲珈?80於代,美國政府運輸部門(U.S.DeptofTransportationFederalTransitAdministrative)已研發相關的技術,並將該技術應用於鐵路土傳噪音量度及預測上。本文報告隧道鑽機所產生的土傳噪音及震動級數1/3倍頻帶數值的量度及預測。比較地面震動峰值速度(PPV)、最高(Lmax)噪聲和振動級數按快速和緩慢的時間常數和整體百分比(Percentile)數值列出。     

Hormone replacement therapy and the risk of stroke. Follow-up of a population-based cohort in Sweden

BACKGROUND: The protective effect of postmenopausal estrogen replacement therapy on coronary heart disease has been shown in several studies. However, the effect on stroke is more controversial, and data on estrogen-progestin combinations are sparse. METHODS: A total of 23,088 women living in the Uppsala (Sweden) Health Care Region were identified from pharmacy records as having been prescribed noncontraceptive estrogens during 1977 through 1980. They were followed up from 1977 to 1983 for admissions to the hospital because of a first stroke (International Classification of Diseases, Eighth Revision, codes 430 through 438 and 344). The mean observation time was 5.8 years. The expected number was based on person-years in the cohort and incidence rates in the population of the region. RESULTS: Overall, 361 cases of first stroke were observed in the cohort, as compared with 403.2 expected (relative risk [RR], 0.90; 95% confidence limits, 0.81, 0.99). The RR for acute stroke (International Classification of Diseases, Eighth Revision, codes 431 through 436) was 0.85 (0.75, 0.97). In women younger than 60 years at entry who were prescribed estradiol compounds (1 to 2 mg) or conjugated equine estrogens (0.625 to 1.25 mg), the risk of any stroke was reduced by almost 30% (RR, 0.72; 0.58, 0.88) and the risk of acute stroke was reduced by 40% (RR, 0.61; 0.46, 0.79). Women prescribed a combined estradiol-levonorgestrel brand also had a lowered risk of stroke (RR, 0.61; 0.40, 0.88). Weak compounds (mainly estriol) showed no stroke-protective effect, nor was there any relationship between hormone replacement and risk of subarachnoid hemorrhage. CONCLUSION: Hormone replacement therapy with potent estrogens alone or cyclically combined with progestins can, particularly when started shortly after menopause, reduce the risk of stroke.     

Alcohol intake, Lewis phenotypes and risk of ischemic heart disease. The Copenhagen Male Study

In the Copenhagen Male Study we found an increased risk of ischaemic heart disease (IHD) in men with the Lewis phenotype Le(a-b-). This study investigated whether, within the group of Le(a-b-) men, any conventional risk factors modified their increased risk. Three thousand, three hundred and eighty-three men aged 53 to 75 years were examined in 1985/86 and their morbidity and mortality over the next four years recorded. Three hundred and forty-three men with cardiovascular diseases were excluded at baseline. Potential risk factors examined were: alcohol consumption, physical activity, tobacco smoking, serum cotinine, serum lipids, body mass index, blood pressure, hypertension, non-insulin dependent diabetes mellitus and social class. In eligible men with Le(a-b-), N = 280 (9.6%), alcohol was the only risk factor associated with risk of IHD. There was a significant inverse dose-effect relationship between alcohol consumption and risk. The age-adjusted p-values of trend tests were for risk of non-fatal + fatal IHD: p = 0.03; for risk of fatal IHD: p = 0.02. In eligible men with other phenotypes, N = 2,649 (90.4%) only a limited and non-significant negative association with alcohol. In Le(a-b-) men, a group genetically at increased risk of IHD, the risk was strongly and significantly negatively correlated with alcohol consumption.     

Daseinsanalysis: In defense of the ontological difference.

Reviews the special issue of The Humanistic Psychologist, Psychotherapy for freedom: The daseinsanalytic way in psychology and psychotherapy edited by Erik Craig (Volume 16, Number 1, Spring 1988, 278 pp.). The editor brings together a uniquely developed collection of essays, seminars, and interviews delving into foundational as well as clinically-oriented issues regarding the application of Martin Heidegger's philosophy to the fields of psychiatry and psychotherapy. Craig's edition exhibits a cohesiveness not often found in edited volumes, and it manages to be inspiring to the more advanced reader while remaining accessible to the introductory student. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

PDLLA microspheres containing steroids: spray-drying, o/w and w/o/w emulsifications as preparation methods

Sea urchins of the genus Arbacia (order Stirodonta) have discontinuous allopatric distributions ranging over thousands of kilometers. Mitochondrial DNA (mtDNA) sequences were used to reconstruct phylogenetic relationships of four Arbacia species and their geographic populations. There is little evidence of genetic structuring of populations within species, except in two cases at range extremes. The mtDNA sequence differentiation between species suggests that divergence occurred about 4-9 MYA. Gene sequences encoding the sperm protein bindin and its intron were obtained and compared with the mtDNA phylogeny. Sea urchins among the well-studied echinoid order Camarodonta, with degrees of mtDNA divergence similar to those of Arbacia species, are known to have remarkable variation in bindin. However, in Arbacia, little variation in deduced amino acid sequences of bindin was found, indicating that purifying selection acts on the protein. In contrast, bindin intron sequences showed much differentiation, including numerous insertion/deletions. Fertilization experiments performed between a divergent pair of Arbacia species from the Atlantic and Pacific Oceans revealed no evidence of blocks to gamete recognition. In Arbacia, fertilization specificities may have evolved relatively slowly as a result of extensive gene flow within species, greater functional constraint on the bindin polypeptide, or reduced selective pressure for species recognition in singly occurring species.