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排序方式: 共有702条查询结果,搜索用时 187 毫秒
291.
292.
Alpern MB; Lawson TL; Foley WD; Perlman SJ; Reif LJ; Arevalos E; Rimm AA 《Radiology》1986,158(1):45-49
A prospective evaluation of 185 consecutive patients with abdominal pain or suspected hepatic malignancy was performed to compare the diagnostic accuracy of contrast material-enhanced incremental dynamic computed tomography (IDCT) scans with plain CT scans for detection of hepatic masses and fatty infiltration of the liver. After a series of nondynamic plain CT scans, patients were examined at 7.5 scans/min during intravenous injection of 50 g of iodinated contrast material. Enhanced IDCT study was found to be an accurate, reproducible technique for liver evaluation. Of 155 neoplasms measured in 59 patients, liver-to-lesion differences of less than 10 HU were seen in only two tumors in IDCT scans as compared with 31 in plain CT scans. These differences were not significantly affected by lesion size for neoplasms greater than 6 mm in diameter. A confident diagnosis of fatty infiltration (23 patients) could be made when the spleen-minus-liver difference was 25 HU on enhanced IDCT scans and 10 HU on plain CT scans. In eight patients with liver metastases, there was little variation in the attenuation values of normal-appearing liver between serial examination studies (8 HU average). 相似文献
293.
Identification of a novel sarcoglycan gene at 5q33 encoding a sarcolemmal 35 kDa glycoprotein 总被引:9,自引:5,他引:9
294.
Patient satisfaction with the management of infertility 总被引:5,自引:5,他引:5
Souter VL; Penney G; Hopton JL; Templeton AA 《Human reproduction (Oxford, England)》1998,13(7):1831-1836
The objective of this study was to assess patient satisfaction with the
investigation and initial management of infertility. A postal questionnaire
survey was carried out of 1366 women attending outpatient clinics for the
investigation and initial management of infertility at 12 hospitals
throughout Scotland. The response rate to the questionnaire was 59%
(806/1366). Overall, 87% of responders were satisfied or very satisfied
with their care but a number of deficiencies were identified. Thirty-nine
per cent had never been asked to bring their partner to the clinic and 86%
felt they had not been given enough help with the emotional aspects of
infertility. Forty- seven per cent felt they were not given a clear plan
for the future and 23% of those who had been given drug treatments reported
receiving little or no information about the treatment or possible
side-effects. Overall, only a third had been given any written information
and 78% expressed a wish for more written information. Women ranked 'the
information and explanation given' and the 'attitude of the doctor at the
clinic' highly in comparison to other aspects of their care, including
'help with the emotional aspects of infertility'. In general women were
satisfied with their care but improvements may be made by giving more
explanation and written information and by adopting a more couple-centred
approach. Where resources allow, clinics should take steps to address the
emotional aspects of infertility.
相似文献
295.
296.
Cleavage, aggregation and toxicity of the expanded androgen receptor in spinal and bulbar muscular atrophy 总被引:3,自引:17,他引:3
Spinal and bulbar muscular atrophy (SBMA) is a neurodegenerative disease
caused by the expansion of a polyglutamine repeat within the androgen
receptor (AR). We have studied the mutant AR in an in vitro system, and
find both aggregation and proteolytic processing of the AR protein to occur
in a polyglutamine repeat length-dependent manner. In addition, we find the
aberrant metabolism of expanded repeat AR to be coupled to cellular
toxicity, indicating a likely molecular basis for the toxic gain of AR
function that produces neuronal degeneration in SBMA.
相似文献
297.
The OX-40 receptor provides a potent co-stimulatory signal capable of inducing encephalitogenicity in myelin-specific CD4+ T cells 总被引:1,自引:0,他引:1
Kaleeba JA; Offner H; Vandenbark AA; Lublinski A; Weinberg AD 《International immunology》1998,10(4):453-461
The OX-40 receptor, a member of the nerve growth factor/tumor necrosis
factor receptor gene family, is expressed preferentially on autoreactive
CD4+ T cells isolated from the site of inflammation in rats with clinical
signs of experimental autoimmune encephalomyelitis (EAE). To examine
whether the OX-40 receptor has biologic relevance to T cell function, we
evaluated the ability of a rat OX-40 receptor- specific antibody to
co-stimulate a myelin basic protein (MBP)-reactive CD4+ T cell line. The
anti-OX-40 antibody provided a potent co- stimulatory signal to CD4+ T
cells when added in conjunction with a submitogenic dose of anti-CD3, but
the anti-OX-40 antibody alone did not produce a mitogenic response. The
magnitude and dose-response of anti-OX-40 co-stimulation was virtually
identical to the signal delivered to T cells when cultured with anti-CD28
in conjunction with anti-CD3. MBP-specific T cells stimulated with both
anti-CD3 and anti- OX-40 antibodies expressed increased mRNA and protein
for IL-2 when compared to anti-CD3 alone. MBP-specific T cells stimulated
with both anti-CD3 and anti-OX-40 antibodies were also able to induce EAE
when transferred into naive Lewis rats. In contrast, cells stimulated with
anti-CD3 alone were not encephalitogenic. These data suggest that the
function of the OX-40 receptor on activated T cells is to provide an
alternative pathway for T cell co-stimulation that may be similar in
potency to the CD28-mediated signal.
相似文献
298.
Apoptosis and expression of apoptotic regulators in the human testis following short- and long-term anti-androgen treatment 总被引:4,自引:0,他引:4
Woolveridge I; Bryden AA; Taylor MF; George NJ; Wu FC; Morris ID 《Molecular human reproduction》1998,4(7):701-707
Apoptosis and its augmentation by androgen withdrawal is an important event
in the testis. In other tissues apoptosis is regulated by genes belonging
to the bcl-2 family. However, little is known about these pathways in the
human testes. Human testes were obtained from patients with prostate
cancer, undergoing orchidectomy for permanent androgen ablative treatment.
The patients were either untreated or had previously received short- or
long-term anti-androgen therapy by cyproterone acetate or GnRH agonist
(goserelin). In comparison with untreated patients, testicular testosterone
concentrations were reduced by 83% in patients treated with cyproterone
acetate and by 99% in patients treated with goserelin. Apoptotic cells were
identified in tissue sections by in-situ end labelling of fragmented DNA.
The expression of Bcl-2, Bcl-xl, Bax, p53 and poly(ADP) ribose polymerase
(PARP) was demonstrated in tissue extracts by Western blotting. Apoptotic
germ cells were present in the spermatogenic epithelium of untreated
patients and patients who received short-term anti-androgen treatment.
There were few or no apoptotic cells in the seminiferous tubules following
long-term anti-androgen treatment. Following short- term treatment, the
concentrations of the apoptosis-related proteins examined did not change.
However, in the long-term treated testes, Bcl- xl and PARP expression
declined, Bax and p53 protein concentrations were unchanged, and Bcl-2 was
up-regulated. In conclusion, apoptosis occurs in spermatogenic cells of the
human testis and may contribute to the regulation of germ cell populations.
The apoptosis-related gene products which have been described in other
tissues are present in the human testis and are modulated by androgenic
stimuli.
相似文献
299.
300.
Preimplantation development of mouse and human embryos biopsied at cleavage stages using a modified displacement technique 总被引:1,自引:1,他引:1
Pierce KE; Michalopoulos J; Kiessling AA; Seibel MM; Zilberstein M 《Human reproduction (Oxford, England)》1997,12(2):351-356
A modified embryo biopsy method was tested on four- and eight-cell stage
mouse embryos and used on human embryos to obtain blastomeres for
preimplantation genetic diagnosis. The biopsy method tested combines zona
drilling and fluid displacement to force one or two cells through an
opening in the zona pellucida of the cleavage-stage embryo. Rates of cell
division and the percentage of mouse embryos forming blastocysts following
biopsy at the eight-cell stage were not significantly different from those
observed in unoperated control embryos. The percentage blastocyst formation
was not significantly different in embryos biopsied at the four-cell stage
and in control embryos, although cell division was significantly retarded
following biopsy. 96% of the mouse blastomeres isolated at the eight-cell
stage were recovered intact and 96% of those placed in culture underwent
cell division. Survival and division of cells isolated at the four-cell
stage were 92 and 84% respectively. Most of the cultured blastomeres
cleaved several times and formed small trophoblast vesicles. Chromosomes
were observed in 59% of blastomeres incubated in the presence of colcemid.
In the initial use of this biopsy technique for human preimplantation
genetic diagnosis, blastocyst formation was observed in 9 of 13 human
embryos biopsied at the 7- to 10-cell stage. These findings support the use
of this biopsy method as an alternative to aspiration techniques.
相似文献