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21.
During spermiogenesis, histone-to-protamine exchange causes chromatin condensation. Spermatozoa from infertile men are known to exhibit an increased protamine-1 (PRM1) to protamine-2 (PRM2) protein ratio. Since patients undergoing testicular sperm extraction (TESE) followed by intracytoplasmic sperm injection (ICSI) reveal low fertilization rates, whether the outcome of ICSI could be related to the percentage of round spermatids expressing PRM1-mRNA and PRM2-mRNA was investigated. Applying in-situ hybridization, 55 testicular biopsies from men undergoing TESE/ICSI were investigated. The percentage of PRM1-mRNA and PRM2-mRNA positive spermatids was significantly (P < 0.0001) decreased in men with at least qualitatively normal spermatogenesis (PRM1-mRNA: 58.4 +/- 13.8%; PRM2-mRNA: 56.4 +/- 11.3%) and impaired spermatogenesis (PRM1-mRNA: 32.6 +/- 10.8%; PRM2-mRNA: 31.7 +/- 11.1%) compared with men with obstructive azoospermia and quantitatively normal spermatogenesis (PRM1-mRNA: 79.9 +/- 4.6%; PRM2-mRNA: 78.1 +/- 5.7%). A positive correlation (r(PRM1) = 0.733; r(PRM2) = 0.784; P < 0.001) was demonstrated between the score and the percentage of PRM1-mRNA and PRM2-mRNA positive spermatids. While successful fertilization was neither related to the score, nor to the percentage of PRM1-mRNA and PRM2-mRNA positive spermatids, a significant (P < 0.05) relationship was demonstrated between successful fertilization and the PRM1-mRNA to PRM2-mRNA ratio. Therefore, the PRM1-mRNA to PRM2-mRNA ratio in round spermatids may serve as a possible predictive factor for the outcome of ICSI.  相似文献   
22.
We report cytogenetic findings in 19 c-Kit-positive gastrointestinal stromal tumors (GISTs) that represent a heterogenous group of mesenchymal neoplasms with respect to site, histology, and biologic behavior. All of the GISTs (5 low-risk, 11 high-risk, 3 recurrences) displayed clonal chromosomal aberrations; 15 were hypo- to near-diploid, and 4 were near-triploid and hypotetraploid. The most common abnormalities were loss of chromosomes 14 and/or 22, demonstrated in 14 GISTs irrespective of site or predominant phenotype. Ten cases (2 low-risk, 5 high-risk, 3 recurrences) were characterized by loss of both chromosomes 14 and 22, 2 cases (1 low-risk, 1 high- risk), by loss of chromosome 14; and 2 high-risk cases, by loss of chromosome 22. Additional chromosomal aberrations occurred preferentially in high-risk and recurrent GISTs, including loss of 9p and 1p in 8 cases each, loss of 15 in 6 cases, loss of 3p in 5 cases, loss of 13q and 10q in 4 cases each, loss of 19 in 3 cases, and complete or partial gains of chromosomes 5 and 4 in 2 cases each. More significantly, 5 of 6 patients with clinically aggressive GISTs, including 2 recurrences and 3 metastasing GISTs, were additionally characterized by loss of 9p; four of these had additional loss of chromosomes 1p and 15. The presented results herein indicate that loss of chromosome 14 and/or 22 is an early change in GIST tumorigenesis irrespective of site or differentiation, whereas malignant transformation and progression of GISTs appear to be associated with an increasing incidence of additional secondary aberrations.  相似文献   
23.
Equipment and procedures were devised for quantifying relatively noise-free recordings of low amplitude chin and lip electromyograms (EMGs) during sleep. A total of 28 REM periods were recorded from 5 young adult female Ss. Tonic EMG levels tended to decline toward their lowest level of the night beginning 5 min in advance of REM periods. With very rare exceptions, the lowest EMG levels of the night were maintained throughout REM sleep. During the 20 min of NREM sleep which followed REM periods, mean EMG levels increased over the REM levels but were lower than those recorded during the 20 min of NREM sleep which preceded the REM periods. This pattern of tonic EMG variation obtained for each of the first 3 REM periods of the night.  相似文献   
24.
Zusammenfassung Es wird eine Möglichkeit zur Definition von Serumfermentaktivitäten angegeben, bei der die obere Grenze des Normalen als eine Klinische Einheit bezeichnet wird. Damit soll dem Kliniker die Auswertung der Serumfermentdiagnostik am Krankenbett erleichtert werden.  相似文献   
25.
The presence of a damaged tube has been suggested in recent studies to have a negative effect on in-vitro fertilization (IVF) outcome. Performing bilateral salpingectomy prior to IVF to maximize pregnancy rates may also result in unnecessary surgery. This case is also an example of the occurrence of interstitial pregnancy after salpingectomy. This unusual type of ectopic pregnancy must be kept in mind when evaluating a patient suspected of a possible early abnormal gestation after assisted reproductive technolologies.   相似文献   
26.
27.
A sample of aphthovirus type C3 strain Resende carrying two polyribocytidilic acid [poly(C)] tracts was cloned in tissue culture. One clone with a poly(C)-rich tract of about 145 nucleotides long (clone 3B) and another with a poly(C)-rich tract of about 230 nucleotides long (clone 12) and a mixture of both were injected intralingually into three steers. Samples from all three animals were recovered during the acute phase of the disease, from the blood and from the feet, and at various days after inoculation from the oesophageal-pharyngeal (OP) fluids. Analysis of the viral RNAs of the positive samples by means of RNase T1 maps on one- and two-dimensional gels showed (1) changes in the electrophoretic mobility of the poly(C)-rich tracts of viruses recovered from the OP fluids at various times after infection; (2) selection of virus populations with poly(C)-rich tracts of increased size; (3) later on, changes in the patterns of oligonucleotides of persistent viruses. These variations may lead to the production of new strains with altered biological properties that may contribute to the maintenance and spread of these viruses in the field.  相似文献   
28.
Early life markers of atopy and asthma   总被引:1,自引:0,他引:1  
Since early intervention could modulate the natural course of atopic disease, the availability of predictive markers is of considerable interest. As long as specific genetic markers are not available, early IgE-responses (hen's egg) together with a positive family history of atopy can be proposed as highly specific and predictive markers, which could define subgroups as potential candidates for secondary prevention.  相似文献   
29.
Sleep deprivation in the rat: VII. Immune function   总被引:5,自引:0,他引:5  
Immune function studies were performed on splenic lymphocytes obtained from rats subjected to total or paradoxical sleep deprivation. Spleen cell counts, in vitro lymphocyte proliferation responses to mitogens, and in vitro and in vivo plaque-forming cell responses to antigens were obtained. Sleep-deprived rats were roughly equivalent to both their yoked controls and home-cage controls in all assays. The results do not support the hypothesis that sleep deprivation results in immune suppression as measured by the above-mentioned parameters.  相似文献   
30.
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