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61.
Pal L; Leykin L; Schifren JL; Isaacson KB; Chang YC; Nikruil N; Chen Z; Toth TL 《Human reproduction (Oxford, England)》1998,13(7):1837-1840
A case series of eight cycles of in-vitro fertilization (IVF) in five women
diagnosed with malignant disorders is presented. These patients chose to
defer definitive treatment for a chance for preservation of potential
fertility. The response of these patients to ovarian stimulation, and the
outcome, was compared with 17 IVF cycles in 12 age- matched patients with
isolated tubal infertility. An apparent adverse influence of malignant
disease on the quality and behaviour of oocytes was observed. Despite a
comparable total number of oocytes per cycle in the two groups, a
significantly reduced percentage of mature oocytes was retrieved per cycle
from patients with malignant diseases. The oocytes from patients with
malignant disorders were of a poorer quality and exhibited a significantly
impaired fertilization rate compared to the controls. We propose that
neoplastic processes, irrespective of the site or cell of origin, may have
a detrimental impact on the biology of oocytes, an effect akin to that seen
on spermatozoa in men with certain malignancies.
相似文献
62.
Antileukemic effect of recombinant tumor necrosis factor alpha in vitro and its modulation by alpha and gamma interferons 总被引:2,自引:0,他引:2
The effect of recombinant human tumor necrosis factor alpha (rTNF- alpha) on human myelogenous leukemia clonogenic cells growing either in semisolid media or in suspension cultures was studied and compared with the effect on normal granulocyte-macrophage progenitors (GM-CFC). Exposure of cells to a range of rTNF-alpha doses including pharmacologically achievable plasma concentrations revealed a large heterogeneity in the response of leukemic clonogenic growth to rTNF- alpha. Only one of 13 specimens was highly resistant to rTNF-alpha. Eight of ten leukemic samples were significantly more sensitive than were normal GM-CFC, particularly within the in vivo achievable dose range (1 x 10(0) to 1 x 10(2) ng/mL). No significantly increased inhibition of either normal or leukemic clonogenic growth could be achieved by increasing the rTNF-alpha concentration above 250 ng/mL. Proliferation of leukemic clonogenic cells (L-CFC) was studied in suspension cultures. In five cases the clonogenic cells were significantly inhibited by rTNF-alpha while in one case no inhibition was observed. The inhibition of L-CFC growth by rTNF-alpha was dose dependent between 1 x 10(0) and 1 x 10(2) ng/mL. In suspension cultures, the TNF effect on L-CFC was a function of time of exposure, particularly with low concentrations of TNF. A remarkably higher inhibition of L-CFC as compared with the total leukemic population was observed in suspension cultures. Stimulation of L-CFC growth by rTNF- alpha was not observed. Normal GM-CFC were inhibited by alpha and gamma interferons (INF-alpha, -gamma) in a dose-related manner, with higher sensitivity of colonies than clusters. The response of GM-CFC to combination of recombinant IFNs and TNF was influenced by the size of clones scored and the source of colony-stimulating activity. The response of L-CFC to recombinant IFN-alpha and/or -gamma was highly variable, and sensitivity to one of the lymphokines did not predict for sensitivity to another. The response of L-CFC to combinations of rTNF- alpha and either IFN-alpha or IFN-gamma was complex, varying from synergistic to additive and indifferent. In three of six specimens, IFN- gamma acted antagonistically with rTNF-alpha, a phenomenon not observed with IFN-alpha. These observations suggest that the action of rTNF- alpha in acute myelogenous leukemia could be exploited therapeutically and the dose-time-response relationship should be considered in designing treatment schedules.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
63.
Aim: To compare the decrease in total serum bilirubin (TSB) concentration during conventional phototherapy in infants treated in supine position exclusively versus infants alternated between exposure in supine and prone position every third hour. Moreover, to survey current practice patterns in two Scandinavian countries as far as alternating exposure. Methods: A total of 112 infants with non‐haemolytic hyperbilirubinaemia, but otherwise healthy, and a gestational age ≥33 weeks were randomized to one of the treatment groups. All infants received phototherapy for 24 h. TSB was measured at start of phototherapy and after 12 and 24 h of treatment. Questionnaires about routines for position changes in infants during phototherapy were sent to all 41 neonatal departments in Denmark and Norway. Results: No statistically significant differences in the decrease in TSB were observed between the two treatment groups: at 12 h of therapy, TSB decreased 32% in both groups and at 24 h 49% and 50%, respectively. In two‐thirds of Danish and Norwegian departments, the infants were routinely turned during phototherapy, most often every third hours. Conclusion: The decrease in TSB was not significantly associated with positioning of the infant during conventional phototherapy. Alternating exposure is widely practiced in Scandinavia but is unnecessary. 相似文献
64.
Jean-Ralph Zahar Carole Schwebel Christophe Adrie Maité Garrouste-Orgeas Adrien Fran?ais Aurélien Vesin Molière Nguile-Makao Alexis Tabah Kevin Laupland Alban Le-Monnier Jean-Fran?ois Timsit 《Critical care (London, England)》2012,16(6):R215
Introduction
As data from Clostridium difficile infection (CDI) in intensive care unit (ICU) are still scarce, our objectives were to assess the morbidity and mortality of ICU-acquired CDI.Methods
We compared patients with ICU-acquired CDI (watery or unformed stools occurring ≥ 72 hours after ICU admission with a stool sample positive for C. difficile toxin A or B) with two groups of controls hospitalized at the same time in the same unit. The first control group comprised patients with ICU-acquired diarrhea occurring ≥ 72 hours after ICU admission with a stool sample negative for C. difficile and for toxin A or B. The second group comprised patients without any diarrhea.Results
Among 5,260 patients, 512 patients developed one episode of diarrhea. Among them, 69 (13.5%) had a CDI; 10 (14.5%) of them were community-acquired, contrasting with 12 (17.4%) that were hospital-acquired and 47 (68%) that were ICU-acquired. A pseudomembranous colitis was associated in 24/47 (51%) ICU patients. The median delay between diagnosis and metronidazole administration was one day (25th Quartile; 75th Quartile (0; 2) days). The case-fatality rate for patients with ICU-acquired CDI was 10/47 (21.5%), as compared to 112/443 (25.3%) for patients with negative tests. Neither the crude mortality (cause specific hazard ratio; CSHR = 0.70, 95% confidence interval; CI 0.36 to 1.35, P = 0.3) nor the adjusted mortality to confounding variables (CSHR = 0.81, 95% CI 0.4 to 1.64, P = 0.6) were significantly different between CDI patients and diarrheic patients without CDI. Compared to the general ICU population, neither the crude mortality (SHR = 0.64, 95% CI 0.34 to 1.21, P = 0.17), nor the mortality adjusted to confounding variables (CSHR = 0.71, 95% confidence interval (CI) 0.38 to 1.35, P = 0.3), were significantly different between the two groups. The estimated increase in the duration of stay due to CDI was 8.0 days ± 9.3 days, (P = 0.4) in comparison to the diarrheic population, and 6.3 days ± 4.3 (P = 0.14) in comparison to the general ICU population.Conclusions
If treated early, ICU-acquired CDI is not independently associated with an increased mortality and impacts marginally the ICU length of stay. 相似文献65.
K.B. Laupland O. Lyytikäinen M. Sgaard K.J. Kennedy J.D. Knudsen C. Ostergaard J.C. Galbraith L. Valiquette G. Jacobsson P. Collignon H.C. Schnheyder 《Clinical microbiology and infection》2013,19(5):465-471
Although the epidemiology of Staphylococcus aureus bloodstream infection (BSI) has been changing, international comparisons are lacking. We sought to determine the incidence of S. aureus BSI and assess trends over time and by region. Population-based surveillance was conducted nationally in Finland and regionally in Canberra, Australia, western Sweden, and three areas in each of Canada and Denmark during 2000–2008. Incidence rates were age-standardized and gender-standardized to the EU 27-country 2007 population. During 83 million person-years of surveillance, 18 430 episodes of S. aureus BSI were identified. The overall annual incidence rate for S. aureus BSI was 26.1 per 100 000 population, and those for methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) were 24.2 and 1.9 per 100 000, respectively. Although the overall incidence of community-onset MSSA BSI (15.0 per 100 000) was relatively similar across regions, the incidence rates of hospital-onset MSSA (9.2 per 100 000), community-onset MRSA (1.0 per 100 000) and hospital-onset MRSA (0.8 per 100 000) BSI varied substantially. Whereas the overall incidence of S. aureus BSI did not increase over the study period, there was an increase in the incidence of MRSA BSI. Major changes in the occurrence of community-onset and hospital-onset MSSA and MRSA BSI occurred, but these varied significantly among regions, even within the same country. Although major changes in the epidemiology of community-onset and hospital-onset MSSA and MRSA BSIs are occurring, this multinational population-based study did not find that the overall incidence of S. aureus BSI is increasing. 相似文献
66.
BACKGROUND:
Although Staphylococcus aureus is a major cause of bloodstream infections, population-based data on these infections in children are limited.OBJECTIVE:
To describe the epidemiology of S aureus bacteremia in children.METHODS:
Population-based surveillance for all incident S aureus bacteremias was conducted among children (18 years of age or younger) living in the Calgary Health Region (Alberta) from 2000 to 2006.RESULTS:
During the seven-year study, 120 S aureus bloodstream infections occurred among 119 patients; 27% were nosocomial, 18% health care associated and 56% community acquired. The annual incidence was 6.5/100,000 population and 0.094/1000 live births. A total of 52% had a significant underlying condition, and this was higher for nosocomial cases. Bone and joint (40%), bacteremia without a focus (33%), and skin and soft tissue infections (15%) were the most common clinical syndromes. Infections due to methicillin-resistant S aureus were uncommon (occurring in one infection) and three patients (2.5%) died.CONCLUSIONS:
S aureus bacteremia is an important cause of morbidity in the paediatric age group. Underlying medical conditions and implanted devices are important risk factors. Methicillin-resistant S aureus and mortality rates are low. 相似文献67.
68.
反相HPLC法测定六味安消胶囊及大黄药材中大黄素的含量 总被引:9,自引:0,他引:9
目的:用反相HPLC法测定六味安消胶囊及大黄药材中大黄素的含量.方法:采用CLC-ODS C18色谱柱(5μm,4.6×150mm),流动相:甲醇-0.4%磷酸溶液(85∶15),检测波长:438nm,流速:1.2ml/min,柱温25℃.结果:大黄素的平均回收率为98.56%(RSD=2.61%,n=12),线性范围为0.0798~0.638μg(r=0.9999).结论:本法快速,准确,灵敏,简便易行. 相似文献
69.
Virulence factors of Escherichia coli isolates that produce CTX-M-type extended-spectrum beta-lactamases 下载免费PDF全文
Pitout JD Laupland KB Church DL Menard ML Johnson JR 《Antimicrobial agents and chemotherapy》2005,49(11):4667-4670
This study determined the phylogenetic groups and virulence factors of 37 Escherichia coli isolates producing types of CTX-M compared with those of 19 isolates producing different types of extended-spectrum beta-lactamases (ESBLs) in a well-defined North American population. Most CTX-M-14 producers (97%) were from phylogenic group D; 67% of the CTX-M-15 producers were from group B2. A single CTX-M-14-producing strain belonged to clonal group A. There were significant prevalence differences for individual virulence factors among CTX-M producers and nonproducers; however, aggregate virulence factor scores were similar. CTX-M producers more commonly caused repeat urinary tract infections. Our results indicate that CTX-M type predicts phylogenetic background, and the virulence potential of ESBL-producing E. coli isolates is a complex issue, requiring further study and ongoing surveillance. 相似文献
70.