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971.
A survey of indications and results of cryopreserved testicular spermatozoa has been performed by French Federation of CECOS from 1 January 96 to 31 December 97. 340 sperm cryopreservations (264 with testicular sperm) has been performed: 252 in excretory azoospermia, 88 in non obstructive azoospermia. 30 cycles of ICSI was performed with frozen-thawed spermatozoa with 6 clinical pregnancies (20%). 相似文献
972.
V Segarra MI Crespo F Pujol J Beleta T Doménech M Miralpeix JM Palacios A Castro A Martinez 《Canadian Metallurgical Quarterly》1998,8(5):505-510
In order to define more precisely the risk of hypoglycaemia in GH-deficient children and to clarify the role of growth hormone (GH) in glucose homeostasis, a 24-h fast was monitored in 10 GH-deficient children aged 1.1-6.5 y. Asymptomatic hypoglycaemia (blood glucose < or = 2.6 mmol/l) occurred in 9/10 children, 2 of whom prematurely interrupted the test. Blood glucose profile was not reproducible between children and had no correlation with age (p = 0.48). Gluconeogenesis was considered as non-altered as read from the normal plasma lactate and pyruvate concentrations throughout the test. Plasma ketone body concentrations increased during the test, but were lower than expected with respect to the decrease of blood glucose. This suggests insufficient ketogenesis which could exacerbate hypoglycaemia in GH-deficient children if brain glucose utilization were not alleviated by ketone body oxidization, as is normally the case. The positive glucose response after glucagon stimulation in 6/10 patients indicated normal hepatic glycogen content. However, these responses were unexpected following the prolonged fast and its concomitant hypoglycaemia, and would therefore tend to suggest a defect in glycogenolysis. These results confirm the tendency to hypoglycaemia, even after infancy, in GH-deficient children. These hypoglycaemias may occur by different types of malfunctioning, such as insufficient ketogenesis or a defect in glycogenolysis. These hypotheses require confirmation by a more systematic study of the metabolic and hormonal changes that occur during fasting in both GH-deficient and normal children. 相似文献
973.
AD Dwarakanath LG Yu C Brookes D Pryce JM Rhodes 《Canadian Metallurgical Quarterly》1995,37(4):585-588
Pyoderma gangrenosum is strongly associated with inflammatory bowel disease and exhibits pathergy, occurring at sites of previous minor trauma. A patient is presented with a 21 year history of extensive ulcerative colitis, who developed pyoderma gangrenosum and arthralgia while receiving high dose corticosteroids for active ulcerative colitis. The arthralgia exhibited pathergy affecting particularly the left temporomandibular joint, which was stressed by an asymmetric bite, and the left elbow, which had been fractured many years previously. This prompted the hypothesis that neutrophils in this condition may be marginated, as a result of increased stickiness of either the neutrophil or the vascular endothelium. The introduction of heparin therapy was associated with rapid resolution of the arthralgia, pyoderma gangrenosum, and ulcerative colitis. 相似文献
974.
975.
An NSF-like ATPase, p97, and NSF mediate cisternal regrowth from mitotic Golgi fragments 总被引:2,自引:0,他引:2
Golgi cisternae regrew in a cell-free system from mitotic Golgi fragments incubated with buffer alone. Pretreatment with NEM or salt washing inhibited regrowth, but this could be restored either by p97, an NSF-like ATPase, or by NSF together with SNAPs and p115, a vesicle docking protein. The morphology of cisternae regrown with p97 and NSF-SNAPs-p115 differed, suggesting that they play distinct roles in rebuilding Golgi cisternae after mitosis. 相似文献
976.
Radiotherapy-induced emesis depends on the site of irradiation, the field size and the dose per fraction and is generally less intense than chemotherapy-induced emesis. Established anti-emetic drugs offer only limited symptom control (50%). Ondansetron, a 5HT3 receptors antagonist, had proven a complete or a major control efficacy (0-2 emetic episodes) of 68 to 95% in three pilot studies (fractionated, single-dose and total body irradiations). In controlled studies, ondansetron efficacy was significantly higher than placebo, metoclopramide and prochlorperazine. The treatment was well tolerated in the different studies. 相似文献
977.
Effect of a new rifamycin derivative, rifalazil, on liver microsomal enzyme induction in rat and dog
T Mae K Hosoe T Yamamoto T Hidaka T Ohashi JM Kleeman PE Adams 《Canadian Metallurgical Quarterly》1998,28(8):759-766
1. The effect of a new rifamycin derivative, rifalazil (KRM-1648), on liver microsomal enzyme induction was studied in rat and dog with repeated oral administration of the compound. Relative liver weight, cytochrome b5 and P450 contents, enzyme activities of NADPH-cytochrome c reductase, aniline hydroxylase, p-nitroanisole O-demethylase, aminopyrine N-demethylase, and erythromycin N-demethylase were measured. 2. In rat, rifalazil treatment at 300 mg/kg/day for 10 days increased cytochrome b5 content but it did not affect liver weight, P450 content or enzyme activities. In contrast, rifampicin and rifabutin increased relative liver weights, cytochrome contents and enzyme activities under similar conditions. 3. In dog, rifalazil did not affect any parameters at 30 or 300 mg/kg/day for 13 weeks. 4. These findings indicate that rifalazil is not an enzyme inducer in rat and dog. This property differs from other rifamycin derivatives such as rifampicin and rifabutin. 相似文献
978.
Cardiovascular events and mortality in newly and chronically depressed persons > 70 years of age 总被引:1,自引:0,他引:1
BW Penninx JM Guralnik CF Mendes de Leon M Pahor M Visser MC Corti RB Wallace 《Canadian Metallurgical Quarterly》1998,81(8):988-994
The role of duration of depressed mood in the prediction of cardiovascular disease (CVD) requires further study, as it has been suggested that emerging depressive symptoms may be a better predictor than persistent depressive symptoms. This prospective cohort study of 3,701 men and women aged > 70 years uses 3 measurement occasions of depressive symptomatology (Center for Epidemiologic Studies-Depression Scale) during a 6-year period to distinguish persons who were newly (depressed at baseline but not at 3 and 6 years before baseline) and chronically depressed (depressed at baseline and at 3 or 6 years before baseline). Their risk of subsequent CVD events and all-cause mortality was compared with that of subjects who were never depressed during the 6-year period. Outcome events were based on death certificates and Medicare hospitalization records. During a median follow-up of 4.0 years, there were 732 deaths (46.2/1,000 person-years) and 933 new CVD events (64.7/1,000 person-years). In men, but not in women, newly depressed mood was associated with an increased risk of CVD mortality (relative risk 1.75, 95% confidence interval [CI] 1.00 to 3.05), new CVD events (relative risk 2.07, 95% CI 1.44 to 2.96), and new coronary heart disease events (relative risk 2.03, 95% CI 1.28 to 3.24) after adjustment for traditional CVD risk factors. The association between newly depressed mood and all-cause mortality was smaller (relative risk 1.40, 95% CI 0.95 to 2.07). Chronic depressed mood was not associated with new CVD events or all-cause mortality. Our findings suggest that newly depressed older men, but not women, were approximately twice as likely to have a CVD event than those who were never depressed. In men, recent onset of depressed mood is a better predictor of CVD than long-term depressed mood. 相似文献
979.
980.
KE Stockbauer D Grigsby X Pan YX Fu LM Mejia A Cravioto JM Musser 《Canadian Metallurgical Quarterly》1998,95(6):3128-3133
In many countries, M1 strains of the human pathogenic bacterium group A Streptococcus are the most common serotype recovered from patients with invasive disease episodes. Strains of this serotype express an extracellular protein that inhibits complement [streptococcal inhibitor of complement (Sic)] and is therefore believed to be a virulence factor. Comparative sequence analysis of the 915-bp sic gene in 165 M1 organisms recovered from diverse localities and infection types identified 62 alleles. Inasmuch as multilocus enzyme electrophoresis and pulsed-field gel electrophoresis previously showed that most M1 organisms represent a distinct streptococcal clone, the extent of sic gene polymorphism was unexpected. The level of polymorphism greatly exceeds that recorded for all other genes examined in serotype M1 strains. All insertions and deletions are in frame, and virtually all nucleotide substitutions alter the amino acid sequence of the Sic protein. These molecular features indicate that structural change in Sic is mediated by natural selection. Study of 70 strains recovered from two temporally distinct epidemics of streptococcal infections in the former East Germany found little sharing of Sic variants among strains recovered in the different time periods. Taken together, the data indicate that sic is a uniquely variable gene and provide insight into a potential molecular mechanism contributing to fluctuations in streptococcal disease frequency and severity. 相似文献