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排序方式: 共有813条查询结果,搜索用时 15 毫秒
71.
72.
Mycobacterial Infections After Renal Transplantation 总被引:5,自引:0,他引:5
HIGGINS RM; CAHN AP; PORTER D; RICHARDSON AJ; MITCHELL RG; HOPKIN JM; MORRIS PJ 《QJM : monthly journal of the Association of Physicians》1991,78(2):145-153
Mycobacterial infections occurred in 11 of 633 (1.7 per cent)recipients of successful renal transplants. There were no casesof tuberculosis in patients receiving chemoprophylaxis, butamongst those who did not receive prophylaxis disease occurredin six of the 27 (22 per cent) high-risk patients. The majorcause of morbidity during treatment was renal allograft rejection,largely due to reduction in immunosuppressive drug therapy. 相似文献
73.
Evelien P. M. Brouwers Berend Terluin Bea G. Tiemens Peter F. M. Verhaak 《Journal of occupational rehabilitation》2009,19(4):323-332
Objective To investigate which factors predict return to work (RTW) after 3 and 6 months in employees sick-listed due to minor mental
disorders. Methods Seventy GPs recruited 194 subjects at the start of sick leave due to minor mental disorders. At baseline (T0), 3 and 6 months
later (T1 and T2, respectively), subjects received a questionnaire and were interviewed by telephone. Using multivariate logistic
regression analyses, we developed three prediction models to predict RTW at T1 and T2. Results The RTW rates were 38% after 3 months (T1) and 61% after 6 months (T2). The main negative predictors of RTW at T1 were: (a)
a duration of the problems of more than 3 months before sick leave; and (b) somatisation. The main negative predictors of
RTW at T2 were: (a) a duration of the problems of more than 3 months before sick leave; (b) more than 3 weeks of sick leave
before inclusion in the study; and (c) anxiety. The main negative predictors of RTW at T2 for those who had not resumed work
at T1 were: (a) more than 3 weeks of sick leave before inclusion in the study; and (b) depression at T1. The predictive power
of the models was moderate with AUC-values between 0.695 and 0.763. Conclusions The main predictors of RTW were associated with the severity of the problems. A long duration of the problems before the
occurrence of sick leave and a long duration of sick leave before seeking help predict a relatively small probability to RTW
within 3–6 months. High baseline somatisation and anxiety, and high depression after 3 months make the prospect even worse.
Since these predictors are readily assessable with just a few questions and a symptom questionnaire, this opens the opportunity
to select high-risk employees for a targeted intervention to prevent long-term absenteeism. 相似文献
74.
Mid-trimester loss--appraisal of a screening protocol 总被引:1,自引:0,他引:1
The main causes for mid-trimester loss are known. There is likely to be
overlap with those of first trimester loss, but the proportions may be
different. We wished to perform an aetiological survey in a large
population of patients with a history of recurrent miscarriage, for
possible explanations for their second trimester miscarriages. Database
analysis of 636 patients attending a UK University Teaching Hospital
dedicated miscarriage clinic between 1991 and 1996 revealed a 25%
prevalence (n = 158) for second trimester miscarriage. Results from an
investigative screening protocol were positive in 50% of cases: 33% (n =
52) tested positive for antiphospholipid syndrome (APS); 8% (n = 13)
fulfilled strict criteria for cervical incompetence; there was a 4%
prevalence of uterine anomaly; 3% for infection (n = 5) and 2% of patients
(n = 3) proved to be hypothyroid. Importantly, dual pathology was found in
5% of patients with a history of second trimester miscarriage. As
idiopathic mid-trimester loss is a diagnosis by exclusion, a high index of
suspicion is required, as are modern diagnostic techniques.
相似文献
75.
76.
Breast MR imaging with loop-gap resonators 总被引:1,自引:0,他引:1
Breast images obtained at 1.5 T using a loop-gap resonator pair as both the excitation and detection device are presented. The efficiency of this approach is high, as judged by the low level of radio frequency (RF) power required to obtain a 90 degree pulse and the uniformity of the RF field within the resonator pair. A modification of the pair geometry provides for reasonable observation of the tissues through the chest wall and laterally to the axillae. 相似文献
77.
78.
79.
A distal single nucleotide polymorphism alters long-range regulation of the PU.1 gene in acute myeloid leukemia 总被引:2,自引:0,他引:2
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80.
GERD FRÖHLIG ARMIN BOLZ JÖRG STRÖBEL MARTIN RUTZ PETER LAWALL HOLGER SCHWERDT MAX SCHALDACH HERMANN SCHIEFFER 《Pacing and clinical electrophysiology : PACE》1998,21(6):1239-1246
Minimizing the geometric surface area of pacing electrodes increases impedance and reduces the current drain during stimulation, provided that voltage (pulse-width) thresholds remain unchanged. This may be feasible by coating the electrode surface to increase the capacity of the electrode tissue interface and to diminish polarization. Ten unipolar, tined leads with a surface area of 1.3 mm2 and a “fractal” coating of Iridium (Biotronik SD-V137) were implanted in the ventricle, and electrogram amplitude (unfiltered), slew-rate, pacing threshold (0.5 ms), and impedance (2.5 V; 0.5 ms) were measured by the 5311 PSA (Medtronic). On days 0, 2, 5, 10, 28, 90, 180, 360 postimplant, sensing threshold (up to 7.0 mV, measuring range 1–14 mV on day 360 only) and the strength duration curve (0.5–4.0 V; 0.03–1.5 ms; steps: 0.5 V; 0.01 ms, respectively) were determined, the minimum charge delivered per pulse (charge threshold), and the impedance were taken from pacemaker telemetry (Intermedics 294–03). Data were compared with those of an earlier series of 20 unipolar, tined TIR-leads (Biotronik) with a surface area of 10 mm2 and a “fractal” coating of titanium nitride. With the model SD-V137 versus TIR, intraoperative electrogram amplitudes were 15.1 ± 6.1 versus 14.4 ± 3.9 mV(NS), slew rates 3.45 ± 1.57 versus 1.94 ± 1.06 V/s (P < 0. 05), pacing thresholds 0.16 ± 0.05 versus 0.52 ± 0.15 V (P < 0.01) and impedance measurements 1,136 ±175 versus 441 ± 73 Ω (P < 0.0001), respectively. During follow-up, sensing thresholds were the same with both leads. Differences in pulse width thresholds lost its significance on day 28 but resumed on day 360 (SD-V137: 0.08 ± 0.04 ms; TIR: 0.16 ± 0.06 ms at 2.5 V; P < 0.01). With an electrode surface of 1.3 mm2, charge per pulse and impedance consistently differed from control, beingO.15 ± 0.15 versus 0. 66 ± 0. 20 μC (P < 0.001) and 1,344 ± 376 versus 538 ± 79 Ω, respectively, one year after implantation (P < 0.0001). In summary, “fractally” coated small surface electrodes do not compromise sensing; by more than doubling impedance against controls they offer pacing thresholds (mainly in terms of charge) that are significantly lower than with the reference electrode. 相似文献