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21.
Human Y chromosome azoospermia factors (AZF) mapped to different subregions in Yq11 总被引:56,自引:0,他引:56
Vogt PH; Edelmann A; Kirsch S; Henegariu O; Hirschmann P; Kiesewetter F; Kohn FM; Schill WB; Farah S; Ramos C; Hartmann M; Hartschuh W; Meschede D; Behre HM; Castel A; Nieschlag E; Weidner W; Grone HJ; Jung A; Engel W; Haidl G 《Human molecular genetics》1996,5(7):933-943
In a large collaborative screening project, 370 men with idiopathic
azoospermia or severe oligozoospermia were analysed for deletions of 76 DNA
loci in Yq11. In 12 individuals, we observed de novo microdeletions
involving several DNA loci, while an additional patient had an inherited
deletion. They were mapped to three different subregions in Yq11. One
subregion coincides to the AZF region defined recently in distal Yq11. The
second and third subregion were mapped proximal to it, in proximal and
middle Yq11, respectively. The different deletions observed were not
overlapping but the extension of the deleted Y DNA in each subregion was
similar in each patient analysed. In testis tissue sections, disruption of
spermatogenesis was shown to be at the same phase when the microdeletion
occurred in the same Yq11 subregion but at a different phase when the
microdeletion occurred in a different Yq11 subregion. Therefore, we propose
the presence of not one but three spermatogenesis loci in Yq11 and that
each locus is active during a different phase of male germ cell
development. As the most severe phenotype after deletion of each locus is
azoospermia, we designated them as: AZFa, AZFb and AZFc. Their probable
phase of function in human spermatogenesis and candidate genes involved
will be discussed.
相似文献
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23.
Clinical profiling of recombinant follicle stimulating hormone (rFSH; Puregon): relationship between serum FSH and efficacy 总被引:9,自引:0,他引:9
Single-dose and multiple-rising dose studies of recombinantfollicle stimulating hormone (rFSH) in hypogonadotrophic maleand female volunteers demonstrated that the rate of FSH absorptionafter i.m. injection is higher in men than in women. In theabsence of endogenous FSH, a correlation between serum FSH andbody weight became apparent. The elimination half-life of rFSHwas not different between the sexes and was comparable withurinary FSH. However, the in-vitro bio:immuno ratio of serumFSH was significantly higher after the administration of rFSHthan after urinary FSH. When rFSH was administered daily witha fixed dose, steady state levels were reached within 3-5 days.Serum FSH concentrations increased in a dose-dependent mannerwhen the daily dose was increased weekly over 3 weeks from 75to 225 IU. In hypogonadotrophic women, rFSH induced normal folliculargrowth whereas oestrogen synthesis was impaired. In women pituitarysuppressed by a high-dose oral contraceptive, the daily administrationof 150 IU rFSH for 1 week induced more and larger antral folliclesthan the same regimen with urinary FSH, whereas the serum immunoactiveFSH concentrations measured 24 h after each dosing were similar.It is concluded that even though equal or lower serum immunoactiveFSH concentrations were obtained following the administrationof rFSH compared with urinary FSH, circulating bioactivity FSHconcentrations were higher. Therefore, the conventional ideathat serum immunoreactive FSH correlates positively with themagnitude of the ovarian response should be reconsidered. 相似文献
24.
25.
Semmler W; Gademann G; Bachert-Baumann P; Zabel HJ; Lorenz WJ; van Kaick G 《Radiology》1988,166(2):533-539
Tumors in 23 patients were studied by means of in vivo phosphorus-31 magnetic resonance (MR) spectroscopy. In five patients, the response to chemotherapy and radiation therapy was monitored in a long-term follow-up study. In one patient, the P-31 MR spectra were recorded during the infusion of chemotherapeutic drugs. In comparison with healthy muscle tissue of patients, the tumors showed elevated inorganic phosphate, phosphomonoester, and phosphodiester peaks and reduced creatine phosphate peaks, whereas the nucleoside 5'-triphosphate levels remained nearly unchanged. Tumor treatment resulted in changes in the ratio of the signal intensity value of creatine phosphate to that of inorganic phosphate and in the sum of these values. In an osteosarcoma, an initial response followed by renewed tumor growth was clearly indicated by changes in these parameters. In the short-term follow-up examination, slight spectral changes were observed during the infusion of chemotherapeutic drugs. Changes in the concentrations of phosphorus metabolites during therapy can therefore be monitored in human tumors by means of P-31 MR spectroscopy. 相似文献
26.
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28.
HJ Greten ;T Greten ;F Brazklewlcz ;F Schroder ;S Sertel ;M Goncalves ;Wendt ;O Karrer ;A Mafalda ;A Remppis 《针灸推拿医学(英文版)》2008,6(5):272-272
Objective: The guiding criteria are considered the backbone of Chinese medicine. They have previously been described as functional features (symptoms) leading to the overall assessment of human functions on the basis of a regulatory (cybernetic) model referring to the I Ging. Methods: The Heidelberg model can explain symptoms such as created by "heat" on a rational physiological level. Results & Conclusion: The overall of physiological symptoms are shown as a schematic draft. The basis of "heat" is considered to be a general increase of microcirculation in the periphery. This leads to a couple of local pathophysiological consequences and sensations like 1) red tongue (the tongue is considered an embryological somatotopic system). 2) Sensation of warmth (by increase of capillary flow). 3) pre-inflammatory state, leading to pain modalities like "worse if pressed", as inflammations tend to be increasingly painful under pressure; 4) reddish skin, the mechanisms by which this is induced may include the release of substance P, therefore accompanied by burning sensation. Systemic pathophysiological consequences may include. Relative lack of fluid in the larger vessels, as fluid supplies peripheral capillary flow. This may lead to water saving mechanisms like thirst, dry mucosa with do, mouth, dry nose, dry lips, dry skin, and also dry stool, yellow and sparse urine. 相似文献
29.
M Size ES Borgstein HJ Haisma 《Malawi medical journal : the journal of Medical Association of Malawi》2005,17(1):12-14
The intensive care unit at Queen Elizabeth Central Hospital (QECH) has 4 beds and offers level 2 care. A retrospective audit of all admissions to the unit during 2002 was carried out. There were a total of 339 admissions giving a bed occupancy rate of 82 %. Surgical patients made up 81 % of admissions. 45% of all admissions were ventilated. Overall mortality was 38%. Ventilated patients had a mortality of 71% compared with 10% for non-ventilated. Data are also presented for mortality within the surgical and paediatric surgical admissions. 相似文献
30.
Kroese ED; Dortant PM; van Steeg H; van Oostrom CT; van der Houven van Oordt CW; van Kranen HJ; de Vries A; Wester PW; van Kreijl CF 《Carcinogenesis》1997,18(5):975-980
E mu-pim-1 transgenic mice are predisposed to develop lymphomas. Due to
their low spontaneous tumour incidence and their increased sensitivity
towards the lymphomagen ethylnitrosourea these mice may present an
interesting model for short-term carcinogenicity testing. Here, we report
on the further exploration of this transgenic mouse model with two
additional carcinogens known to have, among others, the
lymphohaematopoietic system as target, i.e. benzo[a]pyrene (B[a]P) and
12-O-tetradecanoylphorbol-13-acetate (TPA). B[a]P, given three times a week
(by gavage) for 13 weeks at 4.3, 13 or 39 mg/kg body weight, resulted in a
dose-related increase in lymphomas up to a 90% incidence in E(mu)-pim-1
mice during the observation period of 40 weeks. B[a]P also induced tumours
of the forestomach within this observation period, though at a lower
incidence and apparently equally effective in wildtype and transgenic mice.
TPA, on the other hand, was unable to induce lymphomas (or tumours in any
other organ) in either transgenic or wildtype animals within the
observation period of 44 weeks, when applied dermally at the maximum
tolerated dose of 3 microg/mouse, twice a week for 35 weeks. Molecular
analysis showed that B[a]P-induced lymphomas in transgenic mice were of
T-cell origin, 80% of which had elevated levels of c-myc expression. None
of the lymphomas had increased N-myc expression and mutation analysis of
the ras-gene family revealed a K-ras mutation in only one out of eight
tumours investigated. Also, none of the lymphomas showed aberrant
expression of p53 as determined by immunohistochemistry. It is concluded
that the E mu-pim-1 mouse model will not be very suitable for short-term
carcinogenicity testing in general: only genotoxic chemicals that have the
lymphohaematopoietic system as target for carcinogenesis in wild- type
mice, appear to be efficiently identified.
相似文献