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51.
52.
53.
B Boneu M R Buchanan C Caranobe A M Gabaig D Dupouy P Sie J Hirsh 《Thrombosis research》1987,46(6):845-853
In previous studies, we have reported that standard heparin (SH) was cleared by two mechanisms, a saturable mechanism which predominated at low doses (<100 anti-factor Xa U/kg) and a non-saturable mechanism which predominated at higher doses, when the first mechanism became saturated. In this study, we examined the importance of these two mechanisms in the disappearance of a low molecular weight heparin fraction (LMWH) (CY 216), by comparing the pharmacokinetics and the pharmacodyna-mics of a wide range of doses of SH and CY 216 (1.5 to 500 anti-factor Xa U/kg) Pharmacokinetics was measured as the disappearance of 125I-radiolabelled SH or CY 216. Pharmacodynamics was measured as the disappearance of the anti-factor Xa activity of SH and CY 216. We found that the saturable mechanism contributed little to the disappearance of CY 216 and that it was cleared predominantly by the non-saturable mechanism at all doses tested. Thus, at low doses (<100 anti-factor Xa U/kg), SH was cleared more rapidly than CY 216, whereas at higher doses, CY 216 was cleared more rapidly than SH. We conclude that the mechanism of disappearance of LMWH's differ significantly from those of SH, and that this difference may explain the apparent prolonged anticoagulant activity of LMWH's within the therapeutic range doses. 相似文献
54.
Jesse J. Sturm Harold K. Simon Naghma S. Khan Daniel A. Hirsh 《The American journal of emergency medicine》2013
Background
The use of ondansetron in children with vomiting after a head injury has not been well studied. Concern about masking serious injury is a potential barrier to its use.Objective
The aim of this study was to evaluate the use of ondansetron in children with head injury and symptoms of vomiting in the pediatric emergency department (PED) and its effect on return rates and masking of more serious injuries.Design/Methods
Visits to 2 PEDs from 2003 to 2010 with a diagnosis of head injury were evaluated retrospectively. Patients discharged home after a head computed tomography (CT) are the primary cohort for the study. A logistic regression model was used to analyze ondansetron's effects on the likelihood of return to the PED within 72 hours for persistent symptoms. A secondary analysis was performed on patients with a diagnoses of head injury who did not receive a head CT and were discharged.Results
A total of 6311 patients had a diagnosis of head injury, had a head CT performed, and were discharged from the PED. The use of ondansetron increased significantly from 3.7% in 2003 to 22% in 2010 (P < .001). After controlling for demographic/acuity differences, receiving ondansetron in the PED was associated with a lower likelihood of returning within 72 hours (0.49, 95% confidence interval [0.26-0.92]). In patients with head injury who did not have a head CT performed and were sent home, the use of ondansetron in the PED was not associated with an increased risk of missed diagnoses.Conclusion
Ondansetron use in children with a CT scan who are dispositioned home is relatively safe, does not appear to mask any significant conditions, and significantly reduces return visits to the PED. 相似文献55.
Amichai Perlman Bruria Hirsh Raccah Ilan Matok Mordechai Muszkat 《Journal of cardiac failure》2018,24(8):533-536
Background
Because neprilysin is involved in the degradation of amyloid-beta, there is concern that the angiotensin-neprilysin inhibitor sacubitril-valsartan could increase the risk for dementia.Methods
We analyzed adverse event cases submitted to the Food and Drug Administration Adverse Event Report System from July 2015 to March 2017. Cognition- and dementia-related adverse event cases were defined with the use of broad and narrow structured medical queries.Results
During the period evaluated, 9,004 adverse event reports (out of a total of 2,249,479) involved the use of sacubitril-valsartan. Based on the broad definition, sacubitril-valsartan was associated with cognition- and dementia-related adverse events in 459 reports (5.1%), but this was lower than the proportion of these reports among other medications (6.6%, reporting odds ratio [ROR] 0.72, 95% confidence interval [CI] 0.65–0.79). Restricting the comparison to cases with age >60 years and with the use of a comparator group with heart failure resulted in no association between sacubitril-valsartan and dementia-related adverse events, with the use of both the broad and the narrow definitions (ROR 0.87, 95% CI 0.76–1.02, and ROR 1.06, 95% CI 0.4–3.16, respectively).Conclusion
Sacubitril-valsartan is not associated with a disproportionately high rate of short-term dementia-related adverse effect reports. Long-term studies assessing cognitive outcomes are required to better establish the medication's cognition effects. 相似文献56.
A comparison of three months of anticoagulation with extended anticoagulation for a first episode of idiopathic venous thromboembolism 总被引:30,自引:0,他引:30
Kearon C Gent M Hirsh J Weitz J Kovacs MJ Anderson DR Turpie AG Green D Ginsberg JS Wells P MacKinnon B Julian JA 《The New England journal of medicine》1999,340(12):901-907
BACKGROUND: Patients who have a first episode of venous thromboembolism in the absence of known risk factors for thrombosis (idiopathic thrombosis) are often treated with anticoagulant therapy for three months. Such patients may benefit from longer treatment, however, because they appear to have an increased risk of recurrence after anticoagulant therapy is stopped. METHODS: In this double-blind study, we randomly assigned patients who had completed 3 months of anticoagulant therapy for a first episode of idiopathic venous thromboembolism to continue receiving warfarin, with the dose adjusted to achieve an international normalized ratio of 2.0 to 3.0, or to receive placebo for a further 24 months. Our goal was to determine the effects of extended anticoagulant therapy on rates of recurrent symptomatic venous thromboembolism and bleeding. RESULTS: A prespecified interim analysis of efficacy led to the early termination of the trial after 162 patients had been enrolled and followed for an average of 10 months. Of 83 patients assigned to continue to receive placebo, 17 had a recurrent episode of venous thromboembolism (27.4 percent per patient-year), as compared with 1 of 79 patients assigned to receive warfarin (1.3 percent per patient-year, P<0.001). Warfarin resulted in a 95 percent reduction in the risk of recurrent venous thromboembolism (95 percent confidence interval, 63 to 99 percent). Three patients assigned to the warfarin group had nonfatal major bleeding (two had gastrointestinal bleeding and one genitourinary bleeding), as compared with none of those assigned to the placebo group (3.8 vs. 0 percent per patient-year, P=0.09). CONCLUSIONS: Patients with a first episode of idiopathic venous thromboembolism should be treated with anticoagulant agents for longer than three months. 相似文献
57.
58.
Bhattacharya S; MacLennan F; Hamilton MP; Templeton A 《Human reproduction (Oxford, England)》1997,12(7):1440-1442
Although the conventional method of pain relief during outpatient oocyte
recovery involves physician-administered drugs, patient- controlled
analgesia (PCA) offers an alternative technique with the potential to give
women more control over peroperative analgesia. We conducted a prospective
randomized study to compare the effect of fentanyl administered either
through a PCA delivery system or by a physician. Thirty-nine women were
randomized to PCA during egg collection while 42 were allocated to receive
intermittent doses administered by a physician. Pain was evaluated by means
of a 100 mm linear analogue scale. The mean (SD) pain score in the PCA
group was 38.5 (19.8) while in the other group it was 46.1 (21.3) (P =
0.1). In the PCA group, 64% of women felt very satisfied with their
analgesia as compared with 57% in the non-PCA group (P = 0.6). Among the
PCA users, 39% of demands were successful. Significantly more fentanyl
(97.5 microg) was used in the PCA group than in the other group (84.6
microg) (P = 0.03). Though intraoperative PCA with fentanyl is an effective
alternative to physician-administered techniques, many women still feel the
need for more analgesia during the procedure.
相似文献
59.
60.
Novero V; Camus M; Tournaye H; Smitz J; Verheyen G; Joris H; Derde MP; Van Steirteghem AC; Devroey P 《Human reproduction (Oxford, England)》1997,12(1):59-63
Serum follicle stimulating hormone (FSH) is routinely measured when
evaluating the infertile male for intracytoplasmic sperm injection (ICSI).
However, among the sperm parameters, only its relationship with sperm
concentration is well documented. Few investigations concern the
relationship between FSH and sperm motility and morphology, and the results
of ICSI. A retrospective study of 316 couples who underwent ICSI was
carried out to determine the relationships between serum FSH concentrations
in the male and (i) standard sperm parameters_(concentration, motility and
morphology) and (ii) fertilization, cleavage, pregnancy and implantation
rates after ICSI. There was an inverse correlation with sperm concentration
and total motility but no relationship was found with progressive motility
and sperm morphology. Neither was any relationship found between serum FSH
and fertilization, cleavage, pregnancy and implantation rates, and the
results of ICSI. These findings suggest the need to review the routine
measurement of serum FSH in the infertile male when ICSI is the planned
treatment procedure.
相似文献