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81.
The optimal time period for intrauterine insemination (IUI) in relation to either luteinizing hormone (LH) surge or human chorionic gonadotrophin (HCG) administration leading to the best pregnancy rates has not been determined. In this study, 856 consecutive human menopausal gonadotrophin (HMG)-stimulated and 49 natural unstimulated IUI cycles carried out at a reproductive medicine unit affiliated with a tertiary centre were analysed in a retrospective fashion. There were three scenarios in the temporal relationship of the LH surge, HCG administration and artificial insemination. These were (group A) subjects who had an endogenous LH surge but were not given HCG; (group B) subjects who were given HCG after an observed LH surge, and (group C) subjects who were given HCG before the LH surge. The overall pregnancy rate (PR) was 16% per cycle. The PR was 9% in group A, 20% in group B and 14% in group C. The PR in group B was significantly better than group C (P = 0.04). In group B, the longer the time interval between the LH surge and HCG administration, the better the PR up to 20 h (P = 0.025); the timing of IUI based on the LH surge was not critical to the achievement of pregnancy within 3 days. In group C, PR improved with the increasing interval between HCG and IUI from <28 h up to 60 h. We conclude that a better PR is achieved if a spontaneous LH surge occurs before HCG administration, especially where the administration of HCG is delayed 8-20 h after an observed LH surge; the timing of IUI based on the LH surge is not critical to the achievement of pregnancy within 3 days.   相似文献   
82.
The aim of this study was to investigate functional interactions between sorbic acid, alcoholic cosolvents, and pH with respect to pharmacopeial requirements for the antimicrobial preservation of oral liquids. Twenty-seven test formulations of sugar-free syrups with varying amounts of glycerol (18–36%), propylene glycol (4–21%), and sorbic acid (0-0.15%) and with different pH values (5–8) were tested for antimicrobial preservation efficacy after inoculation with spores of Aspergillus niger. Multivariate data analysis revealed that at pH 5 the minimum concentration of sorbic acid necessary for a tenfold decrease of viable spores ranges between 0.08% and 0.10% exhibiting only minor dependence on the cosolvents concentration. Various interactions between sorbic acid and cosolvents could be observed and were discussed on basis of the degree of dissociation and distribution of sorbic acid. All tested preparations, even those free of sorbic acid, met the criteria for oral products with aqueous bases according to USP32-NF27 and JP XV which claim no increase from the initial spore count at 14 and 28 days. The EP requirement, not less than 1 log10 reduction from the initial count at 14 days, was only met by preparations with pH 5 and not less than 0.15% sorbic acid. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:357–367, 2010  相似文献   
83.
Creek  MR; Mani  C; Vogel  JS; Turteltaub  KW 《Carcinogenesis》1997,18(12):2421-2427
The tissue distribution and macromolecular binding of benzene was studied over a dose range spanning nine-orders of magnitude to determine the nature of the dose-response and to establish benzene's internal dosimetry at doses encompassing human environmental exposures. [14C]-Benzene was administered to B6C3F1 male mice at doses ranging between 700 pg/kg and 500 mg/kg body wt. Tissues, DNA and protein were analyzed for [14C]-benzene content between 0 and 48 h post-exposure (625 Ng/kg and 5 microg/kg dose) by accelerator mass spectrometry (AMS). [14C]-Benzene levels were highest in the liver and peaked within 0.5 h of exposure. Liver DNA adduct levels peaked at 0.5 h, in contrast to bone marrow DNA adduct levels, which peaked at 12-24 h. Dose- response assessments at 1 h showed that adducts and tissue available doses increased linearly with administered dose up to doses of 16 mg/kg body wt. Tissue available doses and liver protein adducts plateau above the 16 mg/kg dose. Furthermore, a larger percentage of the available dose in bone marrow bound to DNA relative to liver. Protein adduct levels were 9- to 43-fold greater than DNA adduct levels. These data show that benzene is bioavailable at human-relevant doses and that DNA and protein adduct formation is linear with dose over a dose range spanning eight orders of magnitude. Finally, these data show that the dose of bioactive metabolites is greater to the bone marrow than the liver and suggests that protein adducts may contribute to benzene's hematoxicity.   相似文献   
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Although molecular biologic techniques can now detect minimal numbers of residual cancer cells in patients in complete clinical remission, the clinical significance of minimal residual disease has never been conclusively established. If the detection of minimal residual disease predicts which patients will relapse, then therapy could be altered based upon the detection of these cells. The t(14;18) can be detected by polymerase chain reaction (PCR) amplification in 50% of patients with B-cell non-Hodgkin's lymphoma and allows detection of one lymphoma cell in up to 1 million normal cells. To determine the clinical significance of the detection of minimal residual lymphoma cells in the bone marrow (BM) PCR amplification was used to detect the presence of residual lymphoma cells after autologous BM transplantation (ABMT) in serial BM samples from 134 patients with B-cell lymphoma in whom a bcl- 2 translocation could be detected. PCR analysis was performed on a total of 542 BM samples obtained while these patients were in complete remission. Disease-free survival was markedly increased in patients with no PCR-detectable lymphoma cells in the marrow compared with those in whom residual lymphoma cells were detected (P < .00001), and the presence of detectable lymphoma cells was associated with a 48-fold increase in the risk of relapse. Of the 77 patients (57%) with no PCR- detectable lymphoma cells in their most recent BM sample, none have relapsed. In contrast, all 33 patients (25%) who have relapsed had PCR- detectable lymphoma cells detected in their BM before clinical relapse occurred. In 19 patients (14%), residual lymphoma cells in the BM were detected early following transplantation and subsequently were no longer detectable, although these patients received no further therapy. In these patients, residual lymphoma cells may already have been irreversibly damaged by the high-dose therapy or an endogenous immune mechanism may be capable of eliminating residual lymphoma cells in some patients. Therefore, although the detection of minimal residual disease by PCR following ABMT in patients with lymphoma identifies those patients at high risk of relapse, the presence of residual minimal disease early after transplantation may not be associated with poor prognosis in a small subset of patients. Confirmatory studies will be required to determine more definitively the role of minimal disease detection to identify which patients require additional therapy.  相似文献   
86.
Monoclonal antibody OKT11 was found to compete with sheep red blood cells for binding sites on human lymphocytes. Preincubation of lymphocytes with OKT11 eliminated E-rosette formation. In a study of 142 peripheral blood samples ranging from 1% to over 90% E-rosette- positive cells, comparison to the percent OKT11-positive cells yielded a correlation coefficient of 0.93. In normal donors, subsets of OKT11+ cells were identified using two-color immunofluorescent staining methods with OKT3, OKT4, and OKT8. On the average, approximately 13% of OKT11+ lymphocytes were OKT3- and 13% of OKT11+ lymphocytes were OKT4- and OKT8-. Based on our double antibody fluorescence intensity data, low antigen density OKT11+ lymphocytes were OKT3-. OKT4+ and OKT8+ lymphocytes in normal peripheral lymphocytes have similar OKT11 antigen density.  相似文献   
87.
A 43-year-old male with a phenotypically homogeneous, expanded subset of T cells presented in 1981 with anemia and neutropenia. The surface antigen phenotype of 99% of the peripheral blood lymphocytes was T3+, T8+, T4-, and they were morphologically large granular lymphocytes (LGL). The same cells comprised 37% of the marrow nucleated cells. Eight months after he presented, the peripheral blood T8+, LGL diminished spontaneously, and the anemia and neutropenia completely resolved. The patient remains hematologically normal as of October 1984. To determine if the T8+, LGL represented a clonal expansion, DNA from peripheral blood lymphocytes collected and cryopreserved when the patient was neutropenic and anemic, and when he was hematologically normal, was analyzed for clonal T-cell antigen receptor gene rearrangements. Using Southern blot analysis, a clonal DNA rearrangement was demonstrated, and this clone diminished but was still demonstrable in peripheral blood lymphocytes collected in 1984. The above observations implicate the expanded T8+, LGL in the pathogenesis of the neutropenia and anemia, yet the exact mechanism remains to be elucidated.  相似文献   
88.
Purpose:  To identify factors associated with variability in anatomical and functional response of diabetic macular oedema (DMO) after 4 mg of intravitreal triamcinolone acetonide (ivTA), and for recurrence of macular oedema.
Design:  Pooled analysis of individual data from two randomized controlled trials.
Methods:  This was a multicentre study involving 107 eyes with DMO administered 4 mg ivTA. Predictive factors for response to treatment were evaluated with linear regression analysis. Factors associated with time to recurrence of oedema were studied with Cox proportional hazards modelling. Main outcome measures were maximum improvement in optical coherence tomography (OCT)-measured central foveal thickness (CFT) and best-corrected visual acuity (BCVA), final CFT and BCVA at 12 months and time to oedema recurrence.
Results:  Greater reduction of retinal thickening occurred in eyes with worse baseline thickening ( P  < 0.001). There was also greater improvement of visual acuity in eyes with poorer preoperative BCVA levels ( P  < 0.001). Age, duration of oedema and previous macular laser treatment had no significant effect on maximal BCVA or CFT improvement. Eyes given 4 mg triamcinolone alone were more likely to develop recurrence of oedema at 12 months than those given a combination of 4 mg triamcinolone plus sequential laser (hazard ratio 2.60 [95% confidence interval: 1.45–4.67]).
Conclusion:  Baseline OCT-measured retinal thickening and BCVA are important predictors of maximal anatomical and functional response of DMO to ivTA, respectively. Combination treatment strategy using sequential laser therapy may have a role in delaying recurrence of oedema after triamcinolone.  相似文献   
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SUMMARY To assess the feasibility of performing an ophthalmic assessment on elderly inpatients, we examined 48 patients over 75 years of age who were consecutively admitted to an acute elderly-care ward. Difficulties were encountered in 35 patients (73%). By employing simple methods to overcome these problems, useful information was obtained in all cases and the time taken to complete the examination ranged from six to 20 minutes (mean 7.5 minutes). Doctors looking after elderly patients should be encouraged to assess visual function and must not be deterred by anticipated logistical difficulties.  相似文献   
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