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991.
Previous studies have shown that severe ovarian hyperstimulation syndrome (OHSS) is secondary to circulatory dysfunction due to the simultaneous occurrence of increased vascular permeability and marked arteriolar vasodilation which lead to an intense homeostatic stimulation of the renin-aldosterone and sympathetic nervous systems and antidiuretic hormone (ADH). In the present report, we have investigated the correlation between changes in haematocrit concentration, and white blood cell (WBC) and platelet counts and the severity of OHSS, as assessed by these markers of effective intra- arterial blood volume, in a series of 50 patients. In comparison with recovery values (4-5 weeks after hospital discharge), OHSS patients showed arterial hypotension, tachycardia, oliguria, very high plasma concentrations of renin, aldosterone, norepinephrine and ADH, and increased mean haematocrit values and WBC and platelet counts. The haematocrit concentration values were directly related to the plasma concentrations of vasoactive substances (plasma renin activity, aldosterone, norepinephrine and ADH) during OHSS (P < 0.001). In contrast, no correlation was evident between WBC or platelet counts and neurohormonal measurements during the syndrome. It is concluded that haematocrit, but not WBC or platelet counts, can act as a biological marker of the severity of OHSS as indicated by plasma measurement of volume-dependent endogenous vasoactive substances.   相似文献   
992.
A simple and objective approach to identifying human round spermatids   总被引:2,自引:9,他引:2  
Although round spermatids have been studied extensively using staining techniques and electron microscopy, little information is available about their appearance in living conditions. We describe a method of collecting and identifying round spermatids from ejaculates and testicular biopsies. The validity of the selection procedure was confirmed by fluorescence in-situ hybridization. Based on cell size, morphological characteristics of nucleus and cytoplasm, and on the nucleus/cytoplasm ratio, we harvested a population of cells that was 84% haploid. This procedure can be applied to select spermatids for clinical or research purposes.   相似文献   
993.
994.
Only four cases of chordoma have been described cytogenetically. We report the cytogenetic findings of a fifth case. Chromosome analysis of a primary sacral chordoma from a 69-year-old man showed the following chromosome complement: 43,XY,-2,-3,del(4)(q32),-6,+7,-11,der(12)t(9;12)(q12;p11),add(16)(q23),- 20,add(22)(q13),+mar.  相似文献   
995.
Partial duplication of distal 17q   总被引:3,自引:0,他引:3  
A male propositus and an older sister had a similar pattern of congenital anomalies, including facial asymmetry with hypertelorism, frontal bossing and temporal narrowness, a broad nasal bridge, epicanthal folds, a wide mouth with a thin upper lip, micrognathia, webbed neck, low-set posteriorly angulated ears, and an abnormal hairline. There was also postaxial polydactyly, flexion contractures of the digits, hypotonia, and a congenital heart anomaly. The propositus also had renal anomalies whereas the sister did not, and the sister had a cleft lip and palate not present in her brother. The propositus and a subsequent fetus identified through genetic amniocentesis were determined to have a 46, XY, -18, +der(18),t(17;18)(q25.1;q23)mat chromosome constitution. Clinical findings are compared to those of other reported cases of dup(17q).  相似文献   
996.
HPRT-APRT-deficient mice are not a model for lesch-nyhan syndrome   总被引:4,自引:0,他引:4  
Complete hypoxanthine-guanine phosphoribosyl-transferase (HPRT) deficiency in humans results in the Lesch-Nyhan syndrome which is characterized, among other features, by compulsive self-injurious behavior. HPRT-deficient mice generated using mouse embryonic stem cells exhibit none of the behavioral symptoms associated with the Lesch- Nyhan syndrome. Administration of drugs that inhibit adenine phosphoribosyltransferase (APRT) in HPRT-deficient mice has produced the suggestion that deficiency of APRT in combination with HPRT- deficiency in mice may lead to self-mutilation behavior [C.L. Wu and D.W. Melton (1993) Nature Genet. 3, 235-240]. To test this proposition, we bred HPRT-APRT-deficient mice. Although the doubly-deficient mice excrete adenine and its highly insoluble derivative, 2,8- dihydroxyadenine, which are also associated with human APRT deficiency, additional abnormalities or any self-injurious behavior were not detected. Thus, APRT-HPRT-deficient mice, which are devoid of any purine salvage pathways, show no novel phenotype and are not a model for the behavioral abnormalities associated with the Lesch-Nyhan syndrome as previously suggested.   相似文献   
997.
998.
The performance of hysterosalpingo contrast sonography (Hy Co Sy) as a first-line, outpatient investigation of tubal patency was examined in 500 consecutive, infertile women, at one centre. Hy Co Sy was completed in 463 (92.6%) cases, using a galactose microbubble contrast agent (Echovist-200) and transvaginal sonography. Initial plain scanning identified adnexal pathology in 198 women (39.6%). Examination with Echovist was attempted for 905 tubes and only 67 (7.4%) were not assessable; after the first 100 women this decreased to 35 tubes (4.8%). A sonographic appearance compatible with blocked tubes was found on 118 (14.1%) occasions but it was also possible to identify variations in the appearance/filling/spilling patterns of individual tubes which increased the number assessed as abnormal to 193 (23.0%). Comparison with laparoscopy and dye chromopertubation findings from the past three years was possible for 185 (37%) women, representing 282 tubes, which gave Hy Co Sy an overall concordance rate of 85.8%, sensitivity of 90.4%, specificity of 70.3%, positive predictive value of 91.2% and negative predictive value of 68.2%. Some 51.0% of women described only mild discomfort and there were no significant postprocedure complications. Hy Co Sy appears to be an acceptable first- line screen and may select out women in whom more invasive investigations are likely to reveal pathology.   相似文献   
999.
Data on the chromosome aberrations associated with leiomyosarcomas of soft tissues are limited, complex, and incomplete. The aim of this study was to characterize genetic aberrations associated with this tumor group, to identify consistent regions of involvement and to determine correlations with clinical outcome. Chromosomes were prepared from 10 primary soft-tissue leiomyosarcoma samples, and preparations from four of them, plus the cell line SK-LMS-1, were suitable for analysis using 24-color karyotyping by multifluor fluorescence in situ hybridization. This method allowed rearranged chromosomes to be characterized, which would not have been possible by banding analysis alone. The remaining six chromosome preparations were analyzed using standard Giemsa banding. The chromosome imbalances associated with all the samples were determined by comparative genomic hybridization analysis. Taken together, the results show both intra- and intertumor heterogeneity and considerable complexity. Although no highly consistent rearrangements were found, some regions of the genome frequently were involved, including 1q21, 5p14-pter, and 20q13, which likely harbor genes that play a role in the pathogenesis of soft-tissue leiomyosarcomas. There were no obvious correlations between the chromosomal changes identified and available clinical details.  相似文献   
1000.
分子生物学,特别是重组DNA技术的出现,使我们对人类遗传病有了更深入的认识。这一领域的进展是极其迅速的,其中最明显的例子就是对X-连锁遗传病Duchenne肌营养不良症(DMD)的研究。用基因组探针检测携带者和产前诊断已经证明XJ1.1和pERT基因组探针,及侧翼探针如C7、754和99.6对于发现DMD携带者和产前诊断具有不可估量的价值。受累患儿血清CK水平是正常儿童的100~200倍,但用于检测携带者却不可靠,因为有1/3的肯定携带者的CK水平在正常范围。而应用RFLP进行的连锁分析具有很高的可信  相似文献   
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