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排序方式: 共有632条查询结果,搜索用时 15 毫秒
1.
Local mucosal immunoglobulin E production: does allergy exist in non‐allergic rhinitis? 总被引:2,自引:0,他引:2
In this review, we critically evaluate the evidence for local IgE production in allergic rhinitis mucosa and the concept of local allergy in non-atopic idiopathic rhinitis. Significantly, fewer studies have focused on the disease pathways associated with non-allergic rhinitis compared with their allergic counterparts. Recently, there's been a revival of the hypothesis concerning the existence of local tissue-specific allergic disease confined to the nasal mucosa of some systemically non-atopic rhinitis subjects. Providing the evidence for local mucosal IgE production in allergic rhinitis is a pre-requisite to reviewing its existence in non-allergic rhinitis. In addition, practical and theoretical approaches useful in the detection of allergy in non-allergic rhinitis will be discussed. Furthermore, successful therapeutic regimens used in the treatment of non-allergic rhinitis will be examined as these could provide an insight into the underlying pathophysiology of this common but poorly understood disease. 相似文献
2.
L. E. Boulware M. U. Troll N. Y. Wang N. R. Powe 《American journal of transplantation》2006,6(11):2774-2785
Attitudes toward monetary and nonmonetary incentives for living (LD) and deceased donation (DD) among the U.S. general public and different racial/ethnic and income groups have not been systematically studied. We studied attitudes via a telephone questionnaire administered to persons aged 18-75 in the continental United States. Among 845 participants (85% of randomized households), less than one-fifth participants were in favor of incentives for DD (range 7-17%). Most persons were in favor of reimbursement of medical costs (91%), paid leave (84%) and priority on the waiting list (59%) for LD. African Americans and Hispanics were more likely than Whites to be in favor of some incentives for DD. African Americans were more likely than Whites to be in favor of monetary incentives for LD. Whites with incomes less than $20 000 were more likely than Whites with greater incomes to be in favor of reimbursement for deceased donors' funeral expenses or medical expenses. The U.S. public is not generally supportive of incentives for DD, but is supportive of limited incentives for LD. Racial/ethnic minorities are more supportive than Whites of some incentives. Persons with low income may be more accepting of certain monetary incentives. 相似文献
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5.
Renal uptake of Tl-201 reflects renal perfusion and may have a role in defining renal asymmetry in patients with hypertension who are referred for myocardial scintigraphy. The authors compared two methods of quantitating differential renal uptake of Tl-201, with similar data obtained from the angiographic and renal uptake (RU) phases of Tc-99m DTPA scintigraphy in 35 patients with hypertension. For Tl-201, asymmetry in renal counts was quantitated based on a simple outline technique or on interpolative background subtraction of 5-minute posterior images. Inter-observer and intra-observer variability among duplicate measurements were lower for Tl-201, particularly with interpolative background subtraction, than for Tc-99m DTPA. Renal/background ratios were similar for Tl-201 and RU-phase Tc-99m DTPA images when considering liver, spleen, or inter-renal regions as background; however, paraspinal uptake was relatively higher with Tl-201 (P less than 0.01). Qualitatively, renal asymmetry scores with the two radiotracers agreed (r = 0.89, blinded readings by four observers), although asymmetry was more marked with Tl-201 (P = 0.06). Measurements with Tl-201 agreed with both phases of Tc-99m DTPA (r = 0.96 to 0.98), but interpolative background subtraction systematically yielded greater inter-renal asymmetry than RU (P less than 0.01), reflecting the qualitative impression. Thus, ancillary Tl-201 imaging reflects differences between the kidneys in a fashion similar but not identical to Tc-99m DTPA scintigraphy. 相似文献
6.
Strontium-89 radiotherapy is becoming an important treatment in the palliation of bone pain from osteoblastic metastases. The absorbed dose delivered to bone metastases during 89Sr radiotherapy has been estimated in four patients with metastatic prostatic carcinoma. Patients were injected with a tracer dose of 85Sr-chloride. Blood and urine samples were obtained during the week following injection. Strontium-85 scintigrams of metastases and normal bone were obtained up to 8 wk postinjection. Half of the patients showed elevated whole-body retention; plasma-strontium concentrations were decreased from normal values. Uptake of strontium in metastases was 2-25 times that in normal bone but rates of washout of strontium from metastases were similar to those from normal bone. Absorbed doses delivered in infinite time to the metastases by 89Sr ranged from 21 +/- 4 to 231 +/- 56 cGy/MBq with a median value of 68 cGy/MBq. Doses to red marrow were less by a factor of 2 to 50. These absorbed doses are sufficiently large to be expected to produce a therapeutic benefit. 相似文献
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8.
Ghosh D; Stewart DR; Nayak NR; Lasley BL; Overstreet JW; Hendrickx AG; Sengupta J 《Human reproduction (Oxford, England)》1997,12(5):914-920
The present study was undertaken to assess the temporal association between
the profiles of serum concentrations of oestradiol-17beta, progesterone,
chorionic gonadotrophin (CG) and relaxin in pregnancies established
naturally, and after embryo transfer, as well as in failed pregnancies in
rhesus monkeys. In naturally mated cycles (group 1) a conception rate of
75% was obtained. In group 1, the mean day of CG detection in serum was
11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day
post-ovulation. In group 2, embryo transfer to synchronous, non-mated
surrogate recipients was performed; seven embryo transfer cycles yielded
three pregnancies which were allowed to continue to term and normal infants
were delivered. In embryo transfer cycles the mean day of CG detection was
14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day
post-ovulation. A delay of about 3 days was observed in the appearance in
circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between
natural mated and embryo transfer conception cycles. Significant
differences (P < 0.05 for progesterone and P < 0.03 for oestradiol)
were obtained for the areas under the curves for progesterone and
oestradiol between days 12 and 16 in conception cycles compared with failed
pregnancies. These data provide the first observation of the normal
hormonal signals associated with maternal recognition of transferred
embryos during the peri- implantation period, and suggest that the use of
such an experimental primate embryo transfer model may help to elucidate
components of maternal and embryonic signal-response mechanisms during
embryo implantation.
相似文献
9.
The role of size, sequence and haplotype in the stability of FRAXA and FRAXE alleles during transmission 总被引:2,自引:5,他引:2
Murray A; Macpherson JN; Pound MC; Sharrock A; Youings SA; Dennis NR; McKechnie N; Linehan P; Morton NE; Jacobs PA 《Human molecular genetics》1997,6(2):173-184
Factors involved in the stability of trinucleotide repeats during
transmission were studied in 139 families in which a full mutation,
premutation or intermediate allele at either FRAXA or FRAXE was
segregating. The transmission of alleles at FRAXA, FRAXE and four
microsatellite loci were recorded for all individuals. Instability within
the minimal and common ranges (0-40 repeats for FRAXA, 0-30 repeats for
FRAXE) was extremely rare; only one example was observed, an increased in
size at FRAXA from 29 to 39 repeats. Four FRAXA and three FRAXE alleles in
the intermediate range (41-60) repeats for FRAXA, 31-60 for FRAXE) were
unstably transmitted. Instability was more frequent for FRAXA intermediate
alleles that had a tract of pure CGG greater than 37 although instability
only occurred in two of 13 such transmissions: the changes observed were
limited to only one or two repeats. Premutation FRAXA alleles over 100
repeats expanded to a full mutation during female transmission in 100% of
cases, in agreement with other published series. There was no clear
correlation between haplotype and probability of expansion of FRAXA
premutations. Instability at FRAXA or FRAXE was more often observed in
conjunction with a second instability at an independent locus suggesting
genomic instability as a possible mechanism by which at least some FRAXA
and FRAXE mutations arise.
相似文献
10.
Effect of the ownership of dialysis facilities on patients' survival and referral for transplantation 总被引:11,自引:0,他引:11
BACKGROUND: More than 200,000 patients with end-stage renal disease undergo dialysis in the United States each year, about two thirds in for-profit centers. Economic pressures, such as the decline in inflation-adjusted Medicare payments for dialysis, may compromise the quality of care. Facilities may also be reluctant to refer patients to be evaluated for transplantation because of the loss of revenues from dialysis after patients receive transplants. It is unknown whether for-profit facilities respond more aggressively than not-for-profit facilities to these financial pressures. Therefore, we examined the effect of for-profit ownership of dialysis facilities on patients' survival and referral for possible transplantation. METHODS: We used data from the U.S. Renal Data System to assemble a nationally representative cohort of patients with end-stage renal disease of recent onset. We followed patients for a minimum of three years and a maximum of six years, until death, placement on the waiting list for a renal transplant, or loss to follow-up, or until May 31, 1996. We used proportional-hazards models to assess the effect of the profit status of the dialysis facility on patients' outcomes and adjusted for differences in sociodemographic, clinical, and facility-level characteristics. RESULTS: Of the 3681 patients who were eligible for inclusion, we included 3569 in the analysis of mortality and 3441 in the analysis of the waiting list. The crude mortality rate per 100 person-years of end-stage renal disease was 21.2 for patients treated in for-profit facilities and 17.1 for patients treated in not-for-profit centers (adjusted relative hazard, 1.20; 95 percent confidence interval, 1.02 to 1.42). The likelihood of being placed on the waiting list for a renal transplant was lower for patients treated at for-profit centers (adjusted relative hazard, 0.74; 95 percent confidence interval, 0.56 to 0.98). CONCLUSIONS: In the United States, for-profit ownership of dialysis facilities, as compared with not-for-profit ownership, is associated with increased mortality and decreased rates of placement on the waiting list for a renal transplant. 相似文献