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11.
Acute myocardial disease, which may be associated with abnormal platelet activity, has been reported after routine immunisation. Thirty-two army apprentices undergoing immunisation were studied for changes in the heparin neutralising activity (HNA) of platelet poor plasma. HNA increased after immunisation. This increase in HNA may represent an increase in platelet activation but may also relate to changes in acute phase proteins. These changes were not observed in elderly subjects undergoing immunisation with influenza vaccine. 相似文献
12.
Preimplantation genetic diagnosis principles and ethics 总被引:4,自引:0,他引:4
13.
Life expectancy in British Marfan syndrome populations 总被引:2,自引:0,他引:2
JR Gray AB Bridges RR West L. McLeish AG Stuart JCS Dean MEM Porteous M. Boxer SJ Davies 《Clinical genetics》1998,54(2):124-128
A total of 206 patients with Marfan syndrome were ascertained throughout genetic clinics in Wales and Scotland during the period 1970–1990. There were 45 deaths representing 22% of the cohort. Mean age at death was 45.3 ± 16.5 years. 50% median cumulative survival in the total cohort (n = 206) was 53 years for males and 72 years for females. Multivariate analysis confirmed severity as the best independent indicator of survival. These findings and survival curves will assist in the counselling of British families and individuals with Marfan syndrome. 相似文献
14.
Frataxin is reduced in Friedreich ataxia patients and is associated with mitochondrial membranes 总被引:17,自引:8,他引:17
Campuzano V; Montermini L; Lutz Y; Cova L; Hindelang C; Jiralerspong S; Trottier Y; Kish SJ; Faucheux B; Trouillas P; Authier FJ; Durr A; Mandel JL; Vescovi A; Pandolfo M; Koenig M 《Human molecular genetics》1997,6(11):1771-1780
Friedreich ataxia is a progressive neurodegenerative disorder caused by
loss of function mutations in the frataxin gene. In order to unravel
frataxin function we developed monoclonal antibodies raised against
different regions of the protein. These antibodies detect a processed 18
kDa protein in various human and mouse tissues and cell lines that is
severely reduced in Friedreich ataxia patients. By immunocytofluorescence
and immunocytoelectron microscopy we show that frataxin is located in
mitochondria, associated with the mitochondrial membranes and crests.
Analysis of cellular localization of various truncated forms of frataxin
expressed in cultured cells and evidence of removal of an N-terminal
epitope during protein maturation demonstrated that the mitochondrial
targetting sequence is encoded by the first 20 amino acids. Given the
shared clinical features between Friedreich ataxia, vitamin E deficiency
and some mitochondriopathies, our data suggest that a reduction in frataxin
results in oxidative damage.
相似文献
15.
Recessively inherited L-DOPA-responsive parkinsonism in infancy caused by a point mutation (L205P) in the tyrosine hydroxylase gene 总被引:4,自引:0,他引:4
16.
17.
Y chromosome deletions in azoospermic and severely oligozoospermic men undergoing intracytoplasmic sperm injection after testicular sperm extraction 总被引:11,自引:16,他引:11
Silber SJ; Alagappan R; Brown LG; Page DC 《Human reproduction (Oxford, England)》1998,13(12):3332-3337
Y chromosome deletions encompassing the AZFc region have been reported in
13% of azoospermic men and 7% of severely oligozoospermic men. We examined
the impact of these Y deletions on the severity of testicular defects in 51
azoospermic men undergoing intracytoplasmic sperm injection (ICSI) after
testicular sperm extraction (TESE) and 30 men with severe oligozoospermia
undergoing ICSI after ejaculation of spermatozoa. In addition, five
azoospermic patients shown previously to have Y chromosome deletions
underwent histological evaluation of their previously obtained testis
biopsy specimens. A further 27 azoospermic men underwent TESE-ICSI, but not
Y chromosome DNA testing. Ten of 51 azoospermic men (20%) who underwent
TESE-ICSI and Y-DNA testing were found to be deleted for portions of the Y
chromosome AZFc region. Of these 10, five had spermatozoa retrievable from
the testis, and in two cases the wives became pregnant. Of the 41
azoospermic men with no Y chromosome deletion, 22 (54%) had spermatozoa
retrievable from the testis, and in 12 cases (29%) the wives became
pregnant. Four of 30 (13%) severely oligozoospermic patients were found to
be deleted for AZFc and in three (75%) of these pregnancy was achieved. The
other 26 severely oligozoospermic couples who had no AZFc deletions
underwent ICSI, and 12 (46%) have an ongoing or delivered pregnancy. The
embryo implantation rate was not significantly different for azoospermic
(22%), oligozoospermic (16%), Y-deleted (14%) or Y-intact (18%) men. Of the
total of 19 infertile men who had Y chromosome deletions, 14 had deletions
within Y chromosome intervals 6D-6F, in the AZFc region. Twelve of those 14
had some spermatozoa (however few in number) in the ejaculate or testis.
Five of the Y-deleted men had deletions that extended more proximally on
the Y chromosome, and in none of these could any spermatozoa be observed in
either ejaculate or testis. These results support the concept that, in
azoospermic or oligozoospermic men with Y chromosome deletions limited to
intervals 6D-6F (AZFc), there are generally very small numbers of
testicular or ejaculated spermatozoa. Larger Y deletions, including and
extending beyond the AZFc region and encompassing more Y genes, tend to be
associated with a total absence of testicular spermatozoa. In those cases
where spermatozoa were retrieved, the presence of Y deletions had no
obvious impact on fertilization or pregnancy rate.
相似文献
18.
Mercan R; Mayer JF; Walker D; Jones S; Oehninger S; Toner JP; Muasher SJ 《Human reproduction (Oxford, England)》1997,12(9):1886-1889
The aim of this study was to compare the efficacy of pure follicle
stimulating hormone (FSH) with that of FSH/human menopausal gonadotrophin
(HMG) combination in downregulated cycles. A total of 357 patients was
evaluated retrospectively. Sixty percent of patients in the FSH group and
55% in the FSH/HMG group were new; the others were repeat patients.
Ovulation was suppressed with leuprolide acetate in all patients, followed
by either FSH (n = 218) or FSH/HMG (n = 119). There was no difference in
patients' age, infertility factors, number of ampoules used, length of
stimulation, oestradiol levels on day of human chorionic gonadotrophin
(HCG) administration, number of oocytes recovered or the number of embryos
transferred. Also, nuclear maturity at aspiration and fertilization rates
were not different between the two groups. FSH stimulation resulted in a
significantly higher percentage of mature oocytes that showed the typical
'mature' morphological characteristics (P < 0.0001). The clinical
pregnancy rates per transfer were 40 and 28% in patients stimulated with
pure FSH and FSH/HMG respectively (P < 0.05). The significantly higher
number of immature oocytes matured in vitro in the FSH/HMG group (P =
0.001) suggests a possible effect on in-vitro maturation, due to
luteinizing hormone present in HMG. The difference in mature oocyte quality
may be an important determinant in the higher pregnancy rates for the FSH-
stimulated patients.
相似文献
19.
Role of chemotaxis in the association of motile bacteria with intestinal mucosa: fitness and virulence of nonchemotactic Vibrio cholerae mutants in infant mice. 总被引:5,自引:4,他引:5 下载免费PDF全文
Contrary to earlier findings with all other in vivo and in vitro models of cholera studied, nonchemotactic vibrio mutants showed a relatively greater fitness in 5-day-old infant mice as compared with chemotactic parent or chemotactic revertant strains. This trend was manifest in the relatively greater number of nonchemotactic mutants recovered from the upper small intestine at 4 and 18 h after intragastric infection. The same trend was also revealed in the significantly greater virulence (in terms of time to death) of nonchemotactic mutants as compared with the chemotactic parent or revertant strains. Histological studies in infant mice of the penetration of chemotactic and nonchemotactic vibrios into the mucus gel of the small intestine yielded the same findings as in all other models studied, i.e., significantly greater penetration by chemotactic vibrios. There was no correlation between the relative fitness of nonchemotactic vibrios in the small intestine of infant mice and the rate of recovery of viable nonchemotactic vibrios from that site. In contrast, excellent correlation was found between the relative fitness of nonchemotactic vibrios and a decrease in the recovery of viable cells of the chemotactic strain from the small intestine. This indicates that the relatively greater fitness of the nonchemotactic vibrios in infant mice was only apparent and that the observed phenomenon was actually due to an antibacterial mechanism which prevented the accumulation of the chemotactic strains in the small intestine rather than to any stimulating effect on the nonchemotactic mutant itself. To study the in vivo fate of the inoculum in infant mice, vibrios were labeled with either 32P, 35S, or [3H]thymidine. Specific activity determinations of the 32P label were compatible with the assumption of an accelerated rate of death of the chemotactic parent strain in the small intestine. Results with the other isotopes, however, were significantly different. Indeed, the amount of radioactivity retained in the small intestine after feeding labeled bacteria correlated more closely with the isotope used than with the strain of vibrio under study. Consequently, considerable doubt must be cast on the general validity of this not uncommon technique for determining the in vivo location and the death or survival of radioactively labeled bacteria. 相似文献
20.
止泻散敷脐治疗婴幼儿腹泻100例 总被引:1,自引:1,他引:0
0 引言 腹泻乃小儿最常见病 ,尤以 2岁以下婴幼儿最为常见 .年龄越小 ,发病率越高 ,且多在夏、秋季发病 .小儿患病后惧怕打针 ,服药以及输液 ,给治疗带来一些困难 . 12 a来 ,我们用自拟的止泻散敷脐治疗婴幼儿泄泻 ,效果良好 .1 对象和方法1.1 对象 1998- 0 6 / 1999- 10婴幼儿腹泻发病高峰期门诊病例 10 0 (男 6 6 ,女 34 )例 ,年龄 2月龄~ 5岁 .肠炎 5 8例 ,单纯消化不良 42例 . 6 7例曾多次治疗 ,33例初诊 .凡接受治疗之患儿 ,一律停止用其他药物 .1.2 方法 药物组成 :川椒 12 g,干姜 12 g,小茴香 12 g,白芷 2 0 g,吴茱萸 5 g,… 相似文献