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991.
A 40-year-old man with aortic stenosis and disseminated histoplasmosis did not respond to treatment with itraconazole. Though there was no haemodynamic deterioration, valvar regurgitation, or embolic phenomena a presumptive diagnosis of infective endocarditis was made. This was confirmed at aortic valve replacement. Antifungal treatment was continued for 18 months after valve replacement and serological tests for Histoplasma became progressively more negative during a three year follow up. 相似文献
992.
OBJECTIVE: To examine the hypothalamic-pituitary sites of clomiphene citrate (CC) action in women with polycystic ovarian syndrome (PCOS). DESIGN: Prospective controlled trial. PATIENTS, PARTICIPANTS: Seventeen women with PCOS and 9 normal-cycling women. INTERVENTIONS: Subjects with PCOS received CC, 150 mg/d for 5 days. MAIN OUTCOME MEASURES: Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels and LH pulse characteristics and their response to gonadotropin-releasing hormone (GnRH, 10 micrograms) were examined before and after 3 days of CC in PCOS subjects during a 12-hour frequent sampling study (n = 8). Daily urinary estrone glucuronide and pregnanediol glucuronide levels after CC were compared with concentrations in normal-cycling women through one menstrual cycle. In another nine PCOS subjects, pituitary and ovarian hormonal cyclicity was monitored by daily blood sampling. RESULTS: Thirteen of 17 treated cycles were ovulatory with normal luteal phases. In the ovulatory cycles, serum LH, FSH, estradiol (E2), and estrone levels increased after CC. Luteinizing hormone pulse frequency was unchanged, but LH pulse amplitude increased significantly after CC. Both LH and FSH response to exogenous GnRH was significantly attenuated after CC treatment. In anovulatory cycles, serum LH, FSH, and E2 increased initially and then returned to baseline and remained unchanged for the ensuring 40 days. CONCLUSIONS: Clomiphene citrate-induced ovulation in women with PCOS is accompanied by increased secretion of LH and FSH with enhanced estrogen secretion. The increased LH pulse amplitude after CC, together with decreased pituitary sensitivity to GnRH, suggests a hypothalamic effect. 相似文献
993.
In this study, the number of circulating endothelial cells (CEC) was counted and used as an indicator of the injury of vascular endothelial cells (VEC) in 27 cases with coronary heart disease (CHD), in vivo, CECs were identified with fluorescein-labeled anti-human antibody to factor VIII related antigen. The contents of MDA representing lipid peroxides were also measured in these cases. Meanwhile the number of CEC in normal people was counted as control and compared with that in patients before and after therapy. The results were as follows: The number of CEC and content of MDA in the patients were higher than that in normal people and these two induces were significantly correlated (r = 0.802). The CEC number reflects the severity of CHD. The present investigation suggests that VEC injury induced by the lipid peroxide may play an important role in the pathogenesis of the CHD and CEC counting can be used as a reference for judging the severity and the prognosis of the CHD. 相似文献
994.
Nevus of Ota is a melanotic pigmentary disorder characterized by its distinctive cutaneous distribution involving skin innervated by the trigeminal nerve. Most cases are clinically manifest at birth or around puberty; however, acquired lesions in adults have been reported. We report a case of nevus of Ota acquisita that occurred in an eighty-one-year-old man. 相似文献
995.
The mutagenicity and genotoxicity of cis-[Pt(NH3)2[d(GpG)-N7(1),-N7(2)]] (G*G*), the major DNA adduct of the antitumor drug cisplatin, has been investigated in Escherichia coli. A duplex bacteriophage M13 genome was constructed to contain the G*G* adduct at a specific site in the (-) strand. The singly platinated duplex genome exhibited a survival of 22% relative to that of the unplatinated control genomes, and this value rose to 38% in cells treated with ultraviolet light to induce the SOS response. Singly platinated single-stranded genomes were also produced. Replication of the single- and double-stranded genomes in vivo yielded SOS-dependent, targeted mutations at frequencies of 1.3% and 0.16%, respectively. The mutagenic specificity of G*G* in both single- and double-stranded DNA was striking in that 80-90% of the mutations occurred at the 5'-platinated G. Approximately 80% of the mutations were G-->T transversions at that site. A model of mutagenesis is presented to explain this mutational specificity with respect to current understanding of platinum-DNA adduct structure. 相似文献
996.
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998.
CJ Anobile JA Talbot SJ McCann V Padmanabhan WR Robertson 《Canadian Metallurgical Quarterly》1998,4(7):631-639
The heterogeneity of follicle stimulating hormone (FSH) and luteinizing hormone (LH) was investigated in five women aged 29.4 +/- 3.2 years (mean +/- SD) throughout their menstrual cycles and in five post-menopausal women aged 53.8 +/- 5.6 years. Chromatofocusing (pH range 7-4) revealed menstrual cycle stage- and postmenopausal-related differences in the serum gonadotrophin charge. There were differences in the proportion of FSH with an isoelectric point (pl) > 4.3 across phases of the menstrual cycle (P = 0.019): midcycle (MC) 50%; early to mid-follicular (EMF) 36%; late follicular (LF) 37%, luteal (L) 29% and following the menopause (PM) 17%. There was no significant difference in the proportion of LH with pl > 6.55 between midcycle (53%) and EMF, LF or L phases (36, 43 and 32% respectively); although all were greater than that found in the menopause (13%). Concanavalin A chromatography revealed less (P < 0.005) complex FSH and LH glycoforms at midcycle (63 and 13%) than in the EMF, LF and L phases (90 and 18; 90 and 20 and 93 and 24% respectively). Menopausal gonadotrophins were least complex (FSH 34%, LH 4%). There was a direct relationship between serum FSH and FSH pl/complexity, and less acidic FSH was associated with reduced FSH complexity. Increased oestradiol was associated with basic FSH isoforms during the menstrual cycle and reduced follicular phase FSH complexity. We conclude that changes in gonadotrophin glycoforms occur through the menstrual cycle which are related to changes in the prevailing steroid environment. Following the menopause oestrogenic loss resulted in acidic, relatively simple glycoforms. 相似文献
999.
Every year between one and two million African children under five die of malaria. If one adds to this the contribution of malaria to all-cause infant mortality then clearly the burden of the disease is catastrophic--a disaster quietly happening each and every year. New tools are needed urgently to support those currently available for control of the disease. An effective vaccine remains elusive. This article outlines the potential contribution to malaria control services of satellite information, which is being used by resource managers in other sectors. In particular, it highlights the lessons which can be learned from early warning systems in other areas, especially those designed to respond to famine. An appendix provides a brief introduction to satellite data and their interpretation. 相似文献
1000.