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991.
992.
The therapeutic reactivation of fetal haemoglobin 总被引:3,自引:1,他引:2
Unusually high levels of fetal haemoglobin production can ameliorate sickle
cell disease and beta thalassaemia. Although efforts directed at the
pharmacological stimulation of fetal haemoglobin as an approach to managing
these conditions have met with limited success, there is wide variation in
individual responses. Whether this reflects the particular mutations that
underlie these conditions or other genetic factors remains to be
determined, as does the ideal combination of agents to achieve this end.
These results are encouraging, however, in particular in view of the recent
demonstration that other monogenic diseases, Duchenne muscular dystrophy,
for example, might be amenable to the same therapeutic strategy.
相似文献
993.
Intracardiac extension of intravenous leiomyomatosis 总被引:2,自引:0,他引:2
Kaszar-Seibert DJ; Gauvin GP; Rogoff PA; Vittimberga FJ; Margolis S; Hilgenberg AD; Saal DK; Goldsmith GO 《Radiology》1988,168(2):409-410
A 42-year-old woman was found to have intravenous leiomyomatosis of the uterus with extension into the inferior vena cava and right atrium. Intravenous leiomyomatosis is a rare neoplastic disease characterized by invasion of venous channels by a benign smooth muscle tumor arising either from the wall of a vessel or from a uterine myoma. Intracardiac extension is often initially misdiagnosed as a right atrial myxoma and may cause death by mechanical obstruction. The diagnosis of intravenous leiomyomatosis should be considered in young women with cardiac symptoms associated with a right atrial mass who also have a pelvic mass or who have previously undergone hysterectomy because of leiomyoma uteri. 相似文献
994.
Purpose: The effect of the rate of the interpupillary distance (IPD) change with age on the near fusion free position was investigated in the present study. Methods: Three hundred and fifty-two children aged from 2 to 16 years of age were tested. Interpupillary distance was estimated with a modified Viktorin's method and the near fusion free position was measured with a modified Maddox Wing. Results: The results reveal a significant difference in IPD growth rate between females and males and between children aged below and above 5 years. Most children below 5 years of age were orthophoric, but heterophoria became more common above 5 years of age. Conclusion: The present study suggests that the oculomotor control system for convergence can compensate for age changes in IPD. 相似文献
995.
Sperm output of healthy men in Australia: magnitude of bias due to self- selected volunteers 总被引:9,自引:8,他引:1
Controversial claims, based on a meta-analysis aggregating 61 heterogeneous
observational studies, have been made that human sperm output has decreased
by 50% over the last six decades and that this trend may be due to global
pollution. If true, such effects should be evident in all areas of the
globe; however, longitudinal studies within single centres in Europe and
America have produced conflicting results and there are no reports from the
southern hemisphere. We therefore reviewed semen analyses obtained from
1980-1995 from 689 healthy men volunteering for screening either as
potential sperm donors for a donor insemination programme (n = 509) or to
participate in five male contraception research studies (studies no. 1-5, n
= 180). All were recruited through the Andrology Unit of the Royal Prince
Alfred Hospital, Sydney, by the same doctors using standard methods of
recruiting, screening and laboratory examination throughout the period
1980-1995. Recruitment was by advertising without regard to marital or
fertility status except in two contraceptive efficacy studies (no. 1 and
no. 3) where participants had to be in a stable relationship requiring
contraception. Analysing the first semen sample individually or when
grouped by year of ejaculation, there was no significant difference in
sperm concentration over time or between years or according to year of
birth. During the second half of this period, 180 consecutive volunteers
were recruited by the same doctors and staff for five male contraception
studies. The median sperm concentration for studies no. 1 (103 x 10(6) ml)
and no. 2 (142 x 10(6) ml) were significantly (P < 0.05) higher than for
studies no. 3-5 (84, 67 and 63 x 10(6) ml, respectively) and for potential
sperm donors (median 69 x 10(6) ml). The inconsistency of these estimates
illustrates the magnitude of bias (up to 100%) in sperm output that may
occur in recruiting groups of self-referred volunteers within a single
centre. This highlights the invalidity of extrapolating similar findings on
sperm output of self-selected volunteers to the general male community or
in using such study groups to characterize sperm output in supposedly
'normal' men.
相似文献
996.
Vereb M; Agulnik AI; Houston JT; Lipschultz LI; Lamb DJ; Bishop CE 《Molecular human reproduction》1997,3(1):55-59
Sequenced-tagged site (STS) analysis of the Y chromosome long arm (Yq) of
azoospermic males has identified a minimum common deleted region of several
hundred kilobases in approximately 13% of cases. A candidate azoospermia
gene, DAZ (deleted in azoospermia), has been isolated from this region. DAZ
has also been shown to be absent in severely oligozoospermic males albeit
at a much lower frequency. These data, although highly suggestive, do not
constitute formal proof that DAZ actually plays a role in azoospermia, as
no small intragenic deletions, rearrangements or point mutations in the
gene have been found. In this study we report the screening of DNA from 168
azoospermic/oligospermic males for the presence of the DAZ gene. Deletions
involving DAZ were detected in five out of 43 (11.6%) azoospermic males
whereas none were found in the remaining 125 oligospermic patients. We
present the genomic structure of the 5' end of the DAZ gene together with
its sequence analysis in 30 non-obstructed azoospermic males. No mutations
in DAZ were found in any of the patients sequenced. These data provide no
formal proof that DAZ is AZF. Thus the possibility is still valid that
another gene(s) mapping to the deletion interval may be responsible for, or
contribute to, the observed phenotypes. Alternatively, if DAZ is AZF, they
suggest that the most frequent cause of gene inactivation is via large
deletions possibly mobilized by Y chromosome repetitive sequences.
相似文献
997.
998.
999.
1000.
Summary: Immunological changes and liver disease associated with alpha-1 -antitrypsin deficiency.
A female aged 60 years with heterozygous alpha-1-antitrypsin deficiency developed a progressive and ultimately fatal liver disease with the clinical, biochemical, immunological and histological characteristics of active chronic hepatitis. It is suggested that the hepatic disease of A-AT deficiency be included among the types of liver disease which may initiate a progressive immuno-pathic response. 相似文献
A female aged 60 years with heterozygous alpha-1-antitrypsin deficiency developed a progressive and ultimately fatal liver disease with the clinical, biochemical, immunological and histological characteristics of active chronic hepatitis. It is suggested that the hepatic disease of A-AT deficiency be included among the types of liver disease which may initiate a progressive immuno-pathic response. 相似文献