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991.
Haematocrit, leukocyte and platelet counts and the severity of the ovarian hyperstimulation syndrome 总被引:2,自引:1,他引:2
Fabregues F; Balasch J; Manau D; Jimenez W; Arroyo V; Creus M; Rivera F; Vanrell JA 《Human reproduction (Oxford, England)》1998,13(9):2406-2410
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.
Angelopoulos T; Krey L; McCullough A; Adler A; Grifo JA 《Human reproduction (Oxford, England)》1997,12(10):2208-2216
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.
A simplified serum-free method for preparation and cultivation of human granulosa-luteal cells 总被引:1,自引:0,他引:1
Figenschau Y; Sundsfjord JA; Yousef MI; Fuskevag OM; Sveinbjornsson B; Bertheussen K 《Human reproduction (Oxford, England)》1997,12(3):523-531
A simplified method for the preparation and long-term cultivation of
granulosa-luteal cells in serum-free medium is described. The cells were
harvested from women undergoing in-vitro fertilization, enriched by
sedimentation and dissociated by enzymatic treatment. We demonstrated, by
introducing a synthetic serum replacement (SSR2), that these primary cell
cultures cultivated in monolayers on an extracellular matrix may be used in
experiments exceeding 7 days with low cell loss and cell death. No adverse
effect on progesterone production was found. There was a high diversity in
progesterone production between cells from individual patients. After
several days in culture, the cells were challenged with human chorionic
gonadotrophin which revived the rapidly decreasing progesterone production.
We were unable to demonstrate an increase in cell number after 7 days of
cultivation when the cells were grown in medium supplemented with either
serum or SSR2. The mitogens epidermal growth factor and basic fibroblast
growth factor had no influence on proliferation. We also found that the
present method prevents leukocyte contamination in the granulosa-luteal
cell cultures. Compared with the common method based on the enrichment of
granulosa-luteal cells on a density gradient (Ficoll/Percoll), this method
saves time, labour and expense, in addition to augmenting purity.
相似文献
995.
Unprofessional behavior in medical school is associated with subsequent disciplinary action by a state medical board. 总被引:1,自引:0,他引:1
Maxine A Papadakis Carol S Hodgson Arianne Teherani Neal D Kohatsu 《Academic medicine》2004,79(3):244-249
PURPOSE: To determine if medical students who demonstrate unprofessional behavior in medical school are more likely to have subsequent state board disciplinary action. METHOD: A case-control study was conducted of all University of California, San Francisco, School of Medicine graduates disciplined by the Medical Board of California from 1990-2000 (68). Control graduates (196) were matched by medical school graduation year and specialty choice. Predictor variables were male gender, undergraduate grade point average, Medical College Admission Test scores, medical school grades, National Board of Medical Examiner Part 1 scores, and negative excerpts describing unprofessional behavior from course evaluation forms, dean's letter of recommendation for residencies, and administrative correspondence. Negative excerpts were scored for severity (Good/Trace versus Concern/Problem/Extreme). The outcome variable was state board disciplinary action. RESULTS: The alumni graduated between 1943 and 1989. Ninety-five percent of the disciplinary actions were for deficiencies in professionalism. The prevalence of Concern/Problem/Extreme excerpts in the cases was 38% and 19% in controls. Logistic regression analysis showed that disciplined physicians were more likely to have Concern/Problem/Extreme excerpts in their medical school file (odds ratio, 2.15; 95% confidence interval, 1.15-4.02; p =.02). The remaining variables were not associated with disciplinary action. CONCLUSION: Problematic behavior in medical school is associated with subsequent disciplinary action by a state medical board. Professionalism is an essential competency that must be demonstrated for a student to graduate from medical school. 相似文献
996.
Engle SJ; Womer DE; Davies PM; Boivin G; Sahota A; Simmonds HA; Stambrook PJ; Tischfield JA 《Human molecular genetics》1996,5(10):1607-1610
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.
Evaluation of the performance of hysterosalpingo contrast sonography in 500 consecutive, unselected, infertile women 总被引:1,自引:1,他引:1
Hamilton JA; Larson AJ; Lower AM; Hasnain S; Grudzinskas JG 《Human reproduction (Oxford, England)》1998,13(6):1519-1526
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.
Linkage analysis of candidate regions for coeliac disease genes 总被引:5,自引:0,他引:5
Houlston RS; Tomlinson IP; Ford D; Seal S; Marossy AM; Ferguson A; Holmes GK; Hosie KB; Howdle PD; Jewell DP; Godkin A; Kerr GD; Kumar P; Logan RF; Love AH; Johnston S; Marsh MN; Mitton S; O'Donoghue D; Roberts A; Walker-Smith JA; Stratton MF 《Human molecular genetics》1997,6(8):1335-1339
A strong HLA association is seen in coeliac disease [specifically to the
DQ(alpha1*0501,beta1*0201 heterodimer], but this cannot entirely account
for the increased risk seen in relatives of affected cases. One or more
genes at HLA-unlinked loci also predispose to coeliac disease and are
probably stronger determinants of disease susceptibility than HLA. A recent
study has proposed a number of candidate regions on chromosomes 6p23
(distinct from HLA), 6p12, 3q27, 5q33.3, 7q31.3, 11p11, 15q26, 19p13.3,
19q13.1, 19q13.4 and 22cen for the location of a non-HLA linked
susceptibility gene. We have examined these regions in 28 coeliac disease
families by linkage analysis. There was excess sharing of chromosome 6p
markers, but no support for a predisposition locus telomeric to HLA. No
significant evidence in favour of linkage to coeliac disease was obtained
for chromosomes 3q27, 5q33.3, 7q31.3, 11p11, 19p13.3, 19q13.1, 19q13.4 or
22cen. There was, however, excess sharing close to D15S642. The maximum
non-parametric linkage score was 1.99 (P = 0.03). Although the evidence for
linkage of coeliac disease to chromosome 15q26 is not strong, the well
established association between coeliac disease and insulin dependent
diabetes mellitus, together with the mapping of an IDDM susceptibility
locus (IDDM3) to chromosome 15q26, provide indirect support for this as a
candidate locus conferring susceptibility to coeliac disease in some
families.
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