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991.
This study presents a case of vaginoperineal histologically verified endometriosis at the site of episiotomy scar in a 40-year female subject, 17 years after delivery. Apart from episiotomy during delivery manual revision of the uterus was performed and the cervical rupture managed. Residue symptoms occurs 8 months after the first surgical excision. Clinical data indicate that decidua implantation at the site of episiotomy occurred during the manual revision of the uterine cavity during delivery. 相似文献
992.
993.
D Brown S Kogan E Lagasse I Weissman M Alcalay PG Pelicci S Atwater JM Bishop 《Canadian Metallurgical Quarterly》1997,94(6):2551-2556
The malignant cells of acute promyelocytic leukemia (APL) contain a reciprocal chromosomal translocation that fuses the promyelocytic leukemia gene (PML) with the retinoic acid receptor alpha gene (RAR alpha). To test the hypothesis that the chimera PMLRAR alpha plays a role in leukemogenesis, we expressed a PMLRAR alpha cDNA in myeloid cells of transgenic mice. PMLRAR alpha transgenic mice exhibited impaired neutrophil maturation early in life, which progressed at a low frequency over the course of several months to overt APL. Both the preleukemic state and the leukemia could be transplanted to nontransgenic mice, and the transplanted preleukemia could progress to APL. The APL recapitulated features of the human disease, including a response to retinoic acid. Retinoic acid caused the leukemic cells to differentiate in vitro and in vivo, eliciting remissions of both the preleukemic state and APL in mice. Our results demonstrate that PMLRAR alpha impairs neutrophil differentiation and initiates the development of APL. The transgenic mice described here provide an apparently accurate model for human APL that includes clear evidence of tumor progression. The model should be useful for exploring the molecular pathogenesis of APL and the mechanisms of the therapeutic response to retinoic acid, as well as for preclinical studies of therapeutic regimens. 相似文献
994.
A simple technique for modeling transients in erbium-doped fiber amplifiers (EDFAs) has been applied to a gain-clamped amplifier. Integration of the variables along the length of the amplifier allows the formulation of the problem as a single simple, ordinary, time-dependent differential equation. We demonstrate examples for a typical conventional EDFA and one in which internal out-of-band oscillation is used to clamp the gain 相似文献
995.
GB Lipford T Sparwasser M Bauer S Zimmermann ES Koch K Heeg H Wagner 《Canadian Metallurgical Quarterly》1997,27(12):3420-3426
Certain bacterial immunostimulatory (i.s.) DNA sequences containing unmethylated CpG motifs stimulate antigen-presenting cells (APC) to express a full complement of costimulatory molecules and to produce cytokines including interleukin (IL)-12 and tumor necrosis factor (TNF)-alpha. While IL-12 is key to their T helper cell (Th)1-promoting adjuvant activity, secretion of toxic levels of TNF-alpha is harmful in that it promotes toxic shock. Given the beneficial as well as harmful consequences of i.s. DNA, we investigated the possibility of identifying DNA sequences, i.e. CpG oligodeoxynucleotides (ODN) which differentially activate IL-12 versus TNF-alpha cytokine production in APC. Here, we describe an i.s. DNA sequence with these characteristics. While its potential to induce IL-12 is preserved, its ability to trigger TNF-alpha release is strongly curtailed both in vitro and in vivo. I.s. DNA could be segregated into lethal and non-lethal in a mouse toxic shock model. The non-toxic i.s. DNA was useful as an adjuvant, thus allowing cytotoxic T cell responses to the soluble protein ovalbumin and conferring a resistant Th 1 phenotype to BALB/c mice lethally infected with Leishmania major. This i.s. CpG motif may thus be prototypic for a useful immunostimulating DNA sequence that lacks harmful side effects. 相似文献
996.
Based on a contemporary cognitive-psychoanalytic theory (control-mastery theory; J. Weiss, H. Sampson, & Mount Zion Psychotherapy Research Group, 1986), this study proposed that college students have plans for college that consist of conscious and unconscious goals and obstructions to be overcome in meeting those goals. The construct of unconscious guilt was used to mediate the dual goals of autonomy and attachment. The idiographic plan-formulation method was adapted to derive plans for 12 sophomore women. Acceptable interjudge reliabilities and criterion validity were demonstrated, and several themes in the goals and obstructions were illustrated. Students worried more about mothers than about fathers, particularly when they perceived the mother as weak or needy. The potential of the method for generating inferences about unconscious process for normative development is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
SL Kamholz RJ Brewer G Grijalva J Burack MJ Del Rio M Vaynblatt N Lawson S Squinto WL Fodor AJ Norin 《Canadian Metallurgical Quarterly》1997,21(9):951-955
The lack of sufficient suitable human donor lungs for the many patients requiring pulmonary transplantation as life-saving therapy for end-stage lung diseases has generated extensive interest in cross-species lung transplantation. Ethical concerns and those of animal rights advocates have prompted studies of nonprimate species as potential solid organ donors for humans. This paper provides an overview of some of the laboratory studies of cross-species pulmonary transplantation performed over the past 20 years and focuses, in particular, on more recent work (from our laboratory and others) in the area of porcine-to-primate pulmonary xenotransplantation. 相似文献
998.
One of many problems to be faced when assessing in vivo human muscle mitochondria respiration by phosphorus magnetic resonance spectroscopy (31P-MRS) is the definition of the correct reference population and the values of reference range. To take into account most factors that influence muscle activity as age, sex, physical activity; nutritional state etc., an exceedingly high number of different reference groups are needed. To overcome this problem we developed specific tests to assess separately in vivo the activity and the functionality of muscle mitochondria by 31P-MRS in clinical settings. By activity we refer to muscle whole metabolic activity, i.e. the total oxidative capacity of muscle mitochondria which is influenced by many factors (age, sex, physical activity, nutritional state etc.). By functionality we refer to the qualitative aspects of mitochondrial respiration which depends on the integrity of mitochondrial multienzyme systems and on substrate availability. Our tests have been experienced on some 1200 patients and are currently used to detect deficits of mitochondrial respiration and ion transport in patients with suspected primary or secondary muscle mitochondrial malfunctioning. 相似文献
999.
OBJECTIVE: To evaluate the efficacy of terazosin, an alpha-blocker, for the treatment of idiopathic oligozoospermia. PATIENTS AND METHODS: Thirty couples with infertility whose only detectable abnormality was male idiopathic subfertility entered the study. The diagnosis of idiopathic subfertility in all males studied, aged 26 to 38 years (mean 28.2 years), was confirmed after exclusion of any iatrogenic, systemic, congenital, infectious, autoimmune or endocrinological cause. In order to start with a baseline value before the study, at least three semen samples were evaluated in accordance with the WHO recommendation. Before initiation of treatment, blood samples were drawn for measurement of FSH, LH, testosterone, prolactin, dihydrotestosterone, and estradiol. Fifteen randomly selected patients (Group A) received 2 mg/d of alpha-blocker (terazosin), while another 15 (Group B) were administered an identically packed placebo tablet. Both groups received therapy for 6 months. RESULTS: The mean seminal volume changed insignificantly between the two groups (4.15 +/- 1.95 vs. 4.10 +/- 1.95). There was a statistically significant increase of the sperm concentration in patients who received the alpha-blocker compared to those receiving placebo (24.76 +/- 9.45 vs. 13.15 +/- 11.55 millions/mL; P < .001). No improvement of the mean percentage of abnormal spermatozoa was observed in the treated patients, nor a statistically significant difference of sperm motility in the treated group compared to the placebo group. Side effects were not observed in the patients receiving terazosin treatment, or were so minimal that therapy was continued. The pregnancy rates did not differ between the two groups to a statistically significant degree. CONCLUSION: The administration of terazosin to patients with idiopathic oligozoospermia has a demonstrably positive effect, especially on sperm concentration. 相似文献
1000.
D Ben-Yehuda S Krichevsky EA Rachmilewitz A Avraham GA Palumbo F Frassoni D Sahar H Rosenbaum O Paltiel M Zion Y Ben-Neriah 《Canadian Metallurgical Quarterly》1997,90(12):4918-4923
We previously reported that the abl promoter (Pa) undergoes de novo DNA methylation in the course of chronic myelocytic leukemia (CML). The clinical implications of this finding are the subject of the present study in which samples of CML patients, including a group treated with interferon alpha (IFNalpha) were surveyed. The methylation status of the abl promoter was monitored by polymerase chain reaction (PCR) amplification of the Pa region after digestion with several site-methylation sensitive restriction enzymes. Some 74% of the DNA samples from blood and marrow drawn in the chronic phase were nonmethylated, similar to control samples from non-CML patients. The remaining 26% were partially methylated in the abl Pa region. The latter samples were derived from patients who were indistinguishable from the others on the basis of clinical presentation. Methylated samples were mostly derived from patients known to have a disease of longer duration (26 months v 7.5 months, P = .01). Samples of 30 IFNalpha-treated patients were sequentially analyzed in the course of treatment. Fifteen patients with no evidence of Pa methylation before treatment remained methylation-free. The remainder, who displayed Pa methylation before treatment, reverted to the methylation-free status. The outcome is attributed to IFNalpha therapy, as the Pa methylation status was not reversed in any of the patients treated with hydroxyurea. Methylation of the abl promoter indicates a disease of long-standing, most likely associated with a higher probability of imminent blastic transformation. It appears to predict the outcome of IFNalpha therapy far better than the cytogenetic response. 相似文献