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41.
A literature review conducted for a 1989 article on assessing the quality of life in surgical studies revealed that quality of life was more often mentioned than measured. Few authors reported the use of known, standardized scales. The objective of this study was to determine if and to what extent this situation has changed. A MEDLINE search of surgical studies published between 1989 and 1995 produced over 277 abstracts of surgical studies containing the words "quality of life." The abstracts were studied in three time periods: 1989-1990, 1991-1992 and 1993-1995. Findings indicated that the use of the term "quality of life" increased markedly over the study period, and studies using standardized measures escalated from 27.4% in 1989-1990 to 48.3% in 1993-1995. Those abstracts not stating how quality of life was assessed decreased from 48.4% in the early period to 21.7% in the last period. Of the abstracts reporting studies that used quality of life measures, 33% came from cancer studies, 21.7% from cardiovascular or respiratory studies, 14.8% from gastroenterology studies, 13.4% from nephrology studies and 6.1% from orthopedic studies. Surgical investigators selected a variety of global measures of quality of life as well as disease-specific instruments. The abstracts also revealed that surgeons are using quality-of-life assessment to monitor patients over time, to help select patients for surgery, to determine the effect of surgical treatment and for making policy decisions. Notwithstanding the limitations of this project, there is evidence in the literature that surgeons are increasingly willing to assess the impact of the surgical interventions by quality-of-life measures and are becoming more familiar with the diverse measures used to assess quality of life. 相似文献
42.
1. Lamotrigine is a new antiepileptic drug, chemically unrelated to currently used antiepileptic medication. Its pharmacokinetics can be influenced by concomitant antiepileptic medication. 2. This study was performed to assess the pharmacokinetic profile of lamotrigine in three groups of children treated with different types of comedication: drugs known to induce, to inhibit or to have no clinically significant influence on drug metabolism, respectively. 3. Thirty-one children aged 6 months to 5 years were included and received a 2 mg kg-1 single oral dose. Lamotrigine plasma profiles were different between the three comedication groups. The half-lives (mean +/- s.d.) were: 7.7 +/- 1.8 h, 21.9 +/- 6.8 h, 44.7 +/- 10.2 h in the "inducer', "other' and "inhibitor' groups respectively. 4. Patients were then dosed to steady state, with the dosage adjusted on the basis of the single dose pharmacokinetics to achieve a minimum plasma concentration between 1.5 and 3 mg l-1. The mean minimum plasma concentration for the three groups was 2.54 +/- 1.28 mg l-1 at steady state. 5. Dosage of lamotrigine can be optimised with knowledge of the metabolic effects of antiepileptic comedication. 相似文献
43.
Navigating growth cones need signal transduction machinery to amplify and transmit the effects of extracellular signals throughout the growth cone. In culture, many drugs that affect second messengers are known to modulate neurite extension (with different effects on different neurons), and gradients of calcium influx and cyclic nucleotide analogs can cause growth cones to turn. However, it is not clear which of these responses are physiologically relevant, as axons grow through much more complex environments in vivo. The "exposed brain" preparation in Xenopus embryos provides an experimentally tractable system in which it is possible to study growth, pathfinding, and target recognition of retinal growth cones in vivo, while pharmacologically manipulating their signal transduction systems. These growth cones can also be easily studied in explant culture. We describe preliminary results of parallel in vivo and in vitro experiments using an array of drugs that perturb transduction molecules. Surprisingly, calcium ionophores and cyclic nucleotide analogs have no significant effect on retinal axon growth or pathfinding. Several agents including herbimycin A, ML-7, mastoparan, and RHC80267 inhibit retinal axon growth, both in vivo and in vitro, suggesting that tyrosine kinases, myosin, heterotrimeric G-proteins, and diacylglycerol lipase are important for retinal growth cones navigating in the optic pathway. 相似文献
44.
Wuller Charles E. Nielsen L. Carlisle Clement David M. 《IEEE transactions on nuclear science》1978,25(4):1061-1067
Cable response to X-rays is linear with incident fluence, provided the deposited charge in cable dielectrics is directly proportional to the X-ray flux. To estimate the level at which the linear region ends, we discuss three nonlinear processes that modify the deposited charge profile in a hypothetical cable model: field-limiting in vacuum gaps, ionization effects in air-filled gaps, and radiation-induced dielectric conductivity. The exact level at which limiting of the Norton driver in an elemental length of cable begins depends on the cable geometry and the X-ray source. Estimates of the onset of nonlinearities caused by field-limiting and by dielectric conductivity are found in terms of cable and source parameters. With air-filled gaps, the Norton driver is always nonlinear. In addition to limiting of the Norton drivers, the load response of a long cable may be limited because propagating currents are attenuated by the induced conductivity of the bulk of the dielectric. 相似文献
45.
A gas chromatographic spectrometric assay was used to measure tissue and released acetylcholine and choline in diaphragm preparations of rats previously injected with botulinum toxin type A. Botulinum intoxication was found not to alter the acetylcholine content of rat diaphragms in vivo or in fully paralyzed muscles in vitro. This result provides direct support for the hypothesis that botulinum toxin blocks transmitter release without affecting acetylcholine synthesis. However, in diaphragm preparations in vitro, this toxin was found to inhibit not only the evoked release of acetylcholine but also the spontaneous "leakage" of acetylcholine that is measured at rest. Additional experiments were performed to characterize this action of the toxin. The magnitude of the decline in resting acetylcholine output appears to be too large to be accounted for solely by the known effect of botulinum toxin to reduce the frequency of miniature endplate potentials. The mechanism of this action of botulinum toxin remains an enigma. 相似文献
46.
This study is the conclusion of an exploratory cross-cultural investigation of dream content and organization. Following our report in "Ego Modalities in the Manifest Dreams of Male and Female Chicanos," (Brenneis and Roll, 1975), this paper examines differences in the organization and content of dreams: (1) between Anglo men and women; (2) between Anglo and Chicano men and Anglo and Chicano women; and (3) between Anglos and Chicanos. 相似文献
47.
Recently, Courtois and Pieprzyk proposed a class of algebraic attacks on symmetric block ciphers that takes advantage of a
previously-unexploited property of substitution boxes, or s-boxes, in the round function. This paper gives a brief overview
of this ``overdefined system of equations' (OSE) attack and shows how the attack may be avoided through the use of round
functions constructed according to the CAST design procedure. Such round functions contain a variety of protection mechanisms,
including s-boxes of large dimension, a circular key-dependent rotation step, and combinations of operators from different
algebraic groups. 相似文献
48.
A Pérez-Bouza CB Wigley W Nacimiento J Noth GA Brook 《Canadian Metallurgical Quarterly》1998,9(13):2971-2975
Transplanted olfactory ensheathing cells (OECs) have previously been demonstrated to support axonal growth and myelination in the adult rat CNS. Here, the capacity of donor OECs to control the direction of axonal regeneration has been investigated following transplantation, as elongated columns, into the thalamus of adult rats. The OECs formed a 'glial bridge' which extended from the thalamus to the hippocampus. Transplanted OECs rapidly adopted a spindle-shaped morphology which was orientated along the vertical axis of the transplant. Numerous host axons grew into the transplants and followed the highly orientated OEC cell matrix across the choroid fissure. Thus, the spontaneous elongation and orientation of donor OECs may support highly directional host axonal growth across natural barriers within the CNS. 相似文献
49.
JG Mercer N Hoggard LM Williams CB Lawrence LT Hannah PJ Morgan P Trayhurn 《Canadian Metallurgical Quarterly》1996,8(10):733-735
Leptin, the protein product of the adipose tissue-specific ob (obese) gene (1), reduces the body weight, adiposity and food intake of obese ob/ob mice on peripheral or central injection (2, 3, 4). [125I]leptin binding has been detected in mouse choroid plexus (5), from which a leptin receptor gene was expression cloned (5). The gene has at least 6 splice variants (6, 7). Leptin receptor mRNA was localized in the hypothalamus by in situ hybridization being particularly abundantly expressed in the arcuate nucleus (8). There is evidence linking the physiological effects of injected leptin with hypothalamic neuropeptide Y (9, 10) (NPY), which has potent central effects on food intake and energy balance (11), and is also expressed in the arcuate nucleus. Here we report dual in situ hybridization studies for leptin receptor and NPY gene expression in the mouse arcuate nucleus, where the majority of cells examined expressed both genes. This provides the first direct evidence that leptin acts on cells that express NPY mRNA. 相似文献
50.
Immunotoxins, in chemical conjugate form, have shown limited efficacy in clinical trials in patients with hematologic malignancies. Single-chain immunotoxins (SCIT) provide for enhanced therapeutic efficacy over chemical conjugate forms without additional toxicity and thus may result in improved antitumor activity. We have evaluated two SCITs targeted to CD40, a receptor expressed on most B-lineage hematologic malignancies, for the treatment of non-Hodgkin's lymphoma and multiple myeloma. Both SCITs, G28-5 sFv-PE40 and BD1-G28-5 sFv, were highly potent and specifically cytotoxic against non-Hodgkin's lymphoma and multiple myeloma cell lines. G28-5 sFv-PE40 has proven to be efficacious in SCID mice bearing human non-Hodgkin's lymphoma and multiple myeloma xenografts. Antitumor activity has also been noted in preliminary studies using BD1-G28-5 sFv in non-Hodgkin's lymphoma models. The data presented here indicate that these agents should be considered for use in clinical trials in patients with refractive non-Hodgkin's lymphoma, multiple myeloma and other CD40-expressing hematologic malignancies. 相似文献