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排序方式: 共有973条查询结果,搜索用时 437 毫秒
931.
Zinreich SJ; Wang H; Updike ML; Kumar AJ; Ahn HS; North RB; Rosenbaum AE 《Radiology》1985,157(2):387-390
The diagnostic usefulness, limitations, and adverse reactions associated with computed tomographic myelography using metrizamide were assessed for broad outpatient application. The initial approach was to examine inpatients (n = 38) with low-dose metrizamide (100 mgI/ml). This low dose was believed less likely to be associated with side effects. They were then treated as if they were outpatients, with the liberties this entailed. The consequences of needle puncture were minimized by using a 25-gauge disposable needle. Thirty-four (89%) patients remained free of side effects after the procedure. Subsequently, this technique was extended to 42 outpatients, 38 (90.5%) of whom remained asymptomatic. For comparison, 170 mgI/ml was used in another 25 outpatients, who evidenced more symptoms. The potential medical, economic, and therapeutic benefits of obviating hospitalization by safer outpatient CT myelography seem clear. 相似文献
932.
We have analyzed the T-cell receptor (TCR) V beta repertoire using polymerase chain reaction (PCR) in a cohort of eight patients receiving allogeneic bone marrow transplantation (BMT) from related and unrelated donors at the City of Hope. Results of PCR studies from graft-versus- host disease (GVHD) skin lesions show a bias in the usage of TCR V beta families, whereas examination of peripheral blood (PB) withdrawn at the same time did not reveal a similar phenomenon. In one such family, TCR V beta 2 is predominantly expressed in 7 of 7 biopsy specimens examined. V beta 2 TCR expression from these patients was analyzed more extensively using a combination of individual TCR gene cloning, followed by sequence analysis. We found evidence of oligoclonal expansion of single V beta 2-bearing TCRs in GVHD lesions, and in the PB of some patients after diagnosis of GVHD. In contrast, GVHD-negative biopsy samples showed no evidence for clonotypic TCR amplification. Sequence-specific TCR CDR3 region probes were derived from analysis of the predominant expressed TCR in GVHD lesions, and used to probe Southern blots of amplified V beta 2 TCR mRNA from PB and tissue from BMT recipients and their respective donors. In most cases the probes are highly specific in detecting TCR expression from GVHD lesions alone, although in several instances expression could be detected in PB after GVHD diagnosis. These data provide supporting evidence for the hypothesis that acute GVHD is associated with expansion of T-cell clones expressing antigen-specific TCRs that may contribute to the disease pathology. 相似文献
933.
M D Taylor E W Badger R P Steffen S J Haleen T A Pugsley Y H Shih R E Weishaar 《Journal of medicinal chemistry》1988,31(8):1659-1664
The title compounds are novel double bond isomers of 1,4-dihydropyridine-type calcium channel blockers (CCB). These derivatives were prepared by using the Hantzsch dihydropyridine synthesis. The assignment of structure was based on spectroscopic data and a regiochemically unambiguous synthesis. Several of the analogues inhibited [3H]nitrendipine binding with IC50 values as low as 25 nM. By comparison, nifedipine, a clinically useful 1,4-dihydropyridine CCB, inhibits [3H]nitrendipine binding with an IC50 of 1.6 nM. In the Langendorff rat heart preparation, treatment with the more potent derivatives produced marked dose-related increases in coronary flow with little or no effect on heart rate or contractility, except at the highest concentrations tested. The selectivity for vascular versus cardiac effects was similar to that of nifedipine, i.e., the concentration producing vasodilation was approximately 2 orders of magnitude lower than the concentration eliciting cardiodepression. These novel isomers extend the structure-activity relationships for calcium channel blockers into a series closely related to the 1,4-dihydropyridines. 相似文献
934.
935.
COMPLIANCE MONITORING OF NSAID DRUG THERAPY IN ANKYLOSING SPONDYLITIS, EXPERIENCES WITH AN ELECTRONIC MONITORING DEVICE 总被引:1,自引:1,他引:0
We conducted a randomized, controlled trial to compare once-daily20 mg piroxicam versus once-daily 20 mg tenoxicam in ankylosingspondylitis. We recorded patients' dosing histories with electronicmonitors for an average of 225 days (range 55379) in34 recipients of piroxicam and 31 recipients of tenoxicam. Dosinghistories with the two agents were similar and are combined.Patients took 81% of prescribed doses; 78% once daily (as prescribed)and 3% as two or more daily doses. On 19% of all monitored days,there was no record of a dose being taken; 68% were single no-dosedays, the rest (32%) being 2 to > 10 consecutive no-dosedays. In 3% of monitored days, extra doses were evidently taken,88% as twice daily and 12% as three or more daily doses. Only22% of all patients (14/65) strictly complied with the regimen:one dose daily every day. The remainder alternated between no-dosedays and extra-dose days. We found no correlation between patientcompliance and improvement in reported pain or morning stiffness. KEY WORDS: Ankylosing spondylitis, Patient compliance, NSAIDs 相似文献
936.
Hereditary spherocytosis with spectrin deficiency due to an unstable truncated beta spectrin 总被引:1,自引:0,他引:1
Hassoun H; Vassiliadis JN; Murray J; Yi SJ; Hanspal M; Johnson CA; Palek J 《Blood》1996,87(6):2538-2545
937.
938.
A prospective, randomized, double-blind study for the evaluation of assisted hatching in patients with advanced maternal age 总被引:7,自引:3,他引:4
Lanzendorf SE; Nehchiri F; Mayer JF; Oehninger S; Muasher SJ 《Human reproduction (Oxford, England)》1998,13(2):409-413
The objective of this study was to determine if assisted hatching improved
the rates of implantation, clinical pregnancy and ongoing pregnancy for
in-vitro fertilization (IVF) patients aged > or =36 years. On the day of
oocyte aspiration, consenting patients were randomized according to whether
all embryos underwent the hatching procedure (hatched; n = 41) or all
embryos remained unhatched (controls; n = 48). Patients in both groups were
treated with methylprednisolone and doxycycline starting on the day of
oocyte retrieval and continuing for 4 days. The hatching procedure was
performed approximately 55 h after insemination on all potential embryos
for transfer and employed the release of acidified acid Tyrode's medium
against the zona pellucida to create an opening approximately 20 microm in
diameter. No significant differences were noted in the mean age, number of
oocytes aspirated and number of embryos transferred between the hatched and
control groups. In addition, no significant differences were observed in
the rates of implantation (11.1 versus 11.3%), clinical pregnancy (39.0
versus 41.7%) and ongoing pregnancy (29.3 versus 35.4%) between the hatched
and control groups respectively. These results suggest that assisted
hatching may have no significant impact on IVF success rates in the patient
population studied.
相似文献
939.
Single-lung transplantation: imaging features 总被引:1,自引:0,他引:1
940.
Sakuma H; Fujita N; Foo TK; Caputo GR; Nelson SJ; Hartiala J; Shimakawa A; Higgins CB 《Radiology》1993,188(2):377