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41.
R. Gamzu L. Yogev PhD A. Botchan A. Amit J. B. Lessing D. Lichtenberg G. Paz and H. Yavetz 《Andrologia》1997,29(1):17-21
Summary. The study was conducted to evaluate the diverse effect and clinical significance of TEST yolk buffer treatment on sperm samples of 128 infertile men. Sperm samples were incubated with TEST yolk buffer and control medium (Ham's F-10) at room temperature for 2 h. The hemizona indices (mean ± SE) of the TEST yolk buffer and medium-treated sperm samples were 29 ± 2.3% and 22 ± 1.6%, respectively. Inspection of the individual response of each sperm sample to TEST yolk buffer revealed that 63 samples (49%) improved (double the interassay variation = 28%) their binding to zona pellucida, 36 (28%) remained unchanged, whereas the binding capacity of 29 samples (23%) decreased. Furthermore, TEST yolk buffer treatment of 24 samples (19%) resulted in an increased binding beyond the hemizona index threshold set up at 23%. This level was previously shown to be the cut-off point between fertile and infertile sperm samples. It was concluded that when applied to an unselected group of infertile men, TEST yolk buffer significantly increased sperm binding capacity to the zona pellucida. However, only 19% of the sperm samples showed improvement with clinical significance. The other sperm samples may have improved, remained unchanged or even deteriorated independently on basic sperm variables. Thus, the effect of TEST yolk buffer treatment on sperm binding should be tested prior to its clinical use to avoid possible damage to certain sperm samples. 相似文献
42.
Teresa S. Priebe Edward N. Atkinson Bih-Fang Pan J. Arly Nelson 《Cancer chemotherapy and pharmacology》1992,29(6):485-489
Summary PANC02 is a ductal adenocarcinoma of the pancreas that is resistant to every known class of clinically active antitumor agent. To study the mechanism(s) underlying the intrinsic drug resistance of this tumor, a mammary adenocarcinoma (CA-755) that also grows in C57/BL mice and is known to be drugsensitive was used for comparison. PANC02 resistance and CA-755 sensitivity to several antitumor agents and to X-ray therapy was confirmed in mice, and PANC02 also demonstrated relative resistance in tissue culture. Relative to Chinese hamster ovary (CHO) and CA-755 cells, PANC02 did not appear to show a higher rate of mutation to drug resistance in culture as based on the 6-thioguanine resistance marker. Although P-glycoprotein characteristic of the multidrug resistance (MDR) phenomenon could be demonstrated at the mRNA level using a sensitive RNAse protection assay, the level of expression found was several orders of magnitude lower than that observed in phenotypic MDR cell lines. Furthermore, quinidine failed to increase the sensitivity of PANC02 cells to Adriamycin under conditions that clearly potentiated the toxicity of the drug to a CHO cell line exhibiting classic MDR traits. The heterogeneity in the distribution of drugs was inferred as being significantly greater in PANC02 versus CA-755 cells in vivo as based on measurements of within-animal, within-tumor variance in the distribution of the marker compounds inulin and antipyrine. Although it may not be the only mechanism involved, this greater intratumor heterogeneity in drug distribution could theoretically play a major role in the intrinsic drug resistance of PANC02 in vivo.Supported by grant CH-458 from the American Cancer Society, by grant CA-28034 from the National Cancer Institute, and in part by Cancer Center Core Support grant, NIH-NCI-CA-16672. Animals were maintained in facilities approved by the American Association for Accreditation of Laboratory Animal Care and in accordance with current United States Department of Agriculture, Department of Health and Human Services, and National Institutes of Health regulations and standards 相似文献
43.
Spindler A; Paz S; Berman A; Lucero E; Contino N; enalba A; Tirado S; Santana M; Zeballos A 《Nephrology, dialysis, transplantation》1997,12(1):128-132
Purpose. The objective of this study was to determine
the relationship between muscular strength and bone mineral density (BMD)
in patients undergoing regular haemodialysis. Methods.
The BMD was measured in the lumbar spine (L2L4) and in the proximal femur
(femoral neck and trochanter) with dual-energy X-ray absorptiometry (DEXA
(Lunar DPX). Muscular strength of the extensors, flexors and abductors
muscles of the femur (proximal muscles) and extensors muscles of the back
was measured with an isometric cynamometer. Thirty patients, 15 women with
a mean age of 33.7 years (18-43) and 15 men with a mean age of 15.5 years
(18-65) were included in the study. Results. There was
a positive and significant correlation between the BMD of the femoral neck
and muscular strength of the flexors (r=0.490, P<0.005), the
extensors (r=0.658, P<0.01) and the abductors muscles of the femur
(r=0.671, P <0.0008), as well as between the muscular strength of
the flexors (r=0.413, P <0.02) and extensors muscles of the femur
(r=0.433, P <0.01) with BMD of the trochanter. There was no
correlation between the muscular strength of the back extensor muscles and
the BMD of the lumbar spine (r=-0.119, P NS). There was no correlation
between the BMD and the number of years of haemodialysis therapy (r=-0.032,
P NS), the patient's age (r=-159, P NS), or the value of serum PTH
(r=0.369, P NS) respectively. However, there was a significant correlation
between the BMD of the femoral neck with muscular strength (r=0.602, P
<0.05). Conclusion. This study reveals the
close relationship that exists between muscular strength of the proximal
muscles and the BMD of proximal femur in patients undergoing haemodialysis. 相似文献
44.
45.
Correlation between sperm penetration into the human zona pellucida and in vitro fertilization rates
L. Yogev PhD R. Gamzu R. Hauser A. Botchan A. Amit J. B. Lessing G. Paz and H. Yavetz 《Andrologia》1997,29(2):71-75
Summary. Sperm penetration into the zona pellucida of unfertilized oocytes, and its correlation with in vitro fertilization rates of the sibling oocytes, were assessed. This was performed in order to evaluate the prediction rate of the sperm penetration test into the zona pellucida. Unfertilized oocytes ( n =1872) from 371 cycles were pipetted through a microcapillary, and the remaining sperm cells penetrating the zona pellucida were counted. The mean (±SD) number of spermatozoa that penetrated the zona pellucida of unfertilized oocytes was 12.9±16.37. A significant correlation was found between the fertilization rate and the mean number of spermatozoa that penetrated into the zona pellucida of the unfertilized sibling oocytes (r = 0.48; P < 0.001), or the percent of unpenetrated zonae pellucidae in a cohort (r= —0.43; P < 0.001). However, a distinct variation in the number of spermatozoa that penetrated into the zona pellucida was detected. A step-wise regression analysis proved the number of spermatozoa penetrating the zona pellucida to be more predictive for fertilization rates than the variable of percent of unpenetrated zonae pellucidae. The results imply that although there is interdependence between penetration into the zona pellucida and fertilization rate, the predictive value of sperm penetration test for prognosis and future management after the first in vitro fertilization attempt, is limited. 相似文献
46.
María de Gracia García-Martín María Violante de Paz Juan Antonio Galbis 《Macromolecular chemistry and physics.》1997,198(1):219-227
A chiral poly(3-substituted isobutyl D -aspartate) 12 was synthesized by polymerization of the chiral β-lactam 11 derived from D -glyceraldehyde. The new polyamide was characterized by elemental analyses, and infrared, 1H- and 13C nuclear magnetic resonance spectroscopies. The molecular weight was estimated as 543 000 and 230 000 on the basis of viscosimetric measurements and gel-permeation chromatography, respectively. Polyamide 12 is soluble in a variety of organic solvents including chloroform. 相似文献
47.
48.
J C Tutor A Alvarez-Prechous F Bernabeu M C Pardi?as J M Paz V Lareu 《Clinical biochemistry》1988,21(3):193-198
Urinary D-glucaric acid (DGA) and the activities of gamma-glutamyl transferase (GGT) and other hepatic enzymes in serum were determined in 33 noncirrhotic male alcoholics who had continued to consume alcohol until at least 24 h prior to the taking of samples. DGA excretion was significantly greater in them than in a group of 30 healthy controls (p less than 0.001), exceeding the upper reference level in 38% of the alcoholic cases (as compared with 88% for GGT). In the alcoholic patients, there was highly significant correlation between urinary DGA and serum GGT (r = 0.613, p less than 0.001), suggesting that in both cases the increased levels are due to enzyme induction. None of the biochemical variables studied were significantly correlated with estimated daily alcohol consumption. Urinary DGA levels fell off rapidly with abstinence, and in 31 alcoholic patients who had consumed no alcohol for 5 days, there was no statistically significant correlation between DGA excretion and serum GGT (r = 0.158, p congruent to 0.4). 相似文献
49.
Periodic lateralized epileptiform discharges: etiology, clinical aspects, seizures, and evolution in 130 patients. 总被引:4,自引:0,他引:4
Irene García-Morales M Teresa García Lucia Galán-Dávila Carlos Gómez-Escalonilla Rosana Saiz-Díaz Antonio Martínez-Salio Pilar de la Pe?a Julian A Tejerina 《Journal of clinical neurophysiology》2002,19(2):172-177
The purpose of this study was to analyze the clinical aspects in 130 patients presenting periodic lateralized epileptiform discharges (PLEDs) in their EEG and to compare these results with those found in the literature. Etiology, neurologic deficit, seizure occurrence, and evolution were studied in each patient by historical review. The recordings were obtained on 8- or 16-channel EEGs with electrode placement according to the International 10-20 System. Recordings containing PLEDs were selected. PLEDs were defined as repetitive periodic, focal, or hemispheric epileptiform discharges (spikes, spike and waves, polyspikes, sharp waves) usually recurring every 1 to 2 seconds. The statistical study was carried out via the chi(2) test using the computer program SPSS. The main etiology found in this group of patients was stroke (61 of 130 patients). Other processes found were brain infections, tumors, hematomas, and several other entities grouped together as miscellaneous (anoxic encephalopathy, subarachnoid hemorrhage, craniocerebral trauma, Creutzfeldt-Jacob disease, migraine, multiple sclerosis, and aminophylline intoxication). Half of these patients (65 of 130) developed seizures, mostly partial motor seizures. No significant relation between etiology and seizures was found (chi(2) = 2.81, P = 0.4222). Seizures recurred in 14 of 130 patients during a follow-up of 14.5 months. PLEDs were not recorded in any EEG at the time of seizure recurrence. PLEDs constitute a distinctive but uncommon EEG phenomenon of repetitive, periodic, and stereotyped lateralized complexes. In agreement with the literature, PLEDs were associated with an acute process and occurred early during the course of the illness in all patients studied and were usually associated with structural lesions, with stroke being the main etiology. Traditionally, seizures occur with PLEDs but it is also accepted that they can exist in patients who never develop epileptic activity, either clinically or electrically, as demonstrated in 50% of the patients studied. No significant association between seizures and any etiology could be found. It was not demonstrated that the occurrence of seizures may influence the outcome in any way. 相似文献
50.
Claudio R Cernea Alberto R Ferraz Inês V de Castro Miriam N Sotto Angela F Logullo Carlos E Bacchi André S Potenza 《Otolaryngology--head and neck surgery》2006,134(3):471-475
BACKGROUND: Some skin carcinomas may be very aggressive. Increased expression of the protein p53 has been associated with tumor aggressiveness. In this study, p53 expression was evaluated in basal cell carcinomas (BCC) and squamous cell carcinomas (SCC) with skull base invasion, and was compared to tumors with good outcome. STUDY DESIGN AND SETTING: Expression of p53 was immunohistochemically analyzed and it was reported as present or absent in 24 BCC and 11 SCC with skull base invasion. Control group (good outcome) included 23 BCC and 10 SCC. RESULTS: Expression of p53 was noted in 70.83% of BCC with skull base invasion, compared to 43.48% in the control group (P = 0.058). Regarding SCC, p53 positivity was noted in only 9.09% of SCC with skull base invasion, compared to 40.00% in the control group (P = 0.149). CONCLUSIONS: In this study, p53 expression was more common among BCC with skull base invasion, compared to controls with good outcome, and the difference was considered marginally significant. This proportion was reversed in SCC, but the difference was not statistically significant. EBM rating: B-3b. 相似文献