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1.
Effects of poor glucose handling on arterial stiffness and left ventricular mass in normal children.
AIM: Cardiovascular risk factors can be present in children and young adults. We previously found abnormal microvascular function in children who had glucose intolerance and insulin resistance. The aim of the present study was to investigate whether they also have abnormalities in left ventricular mass (LVM) and arterial stiffness. METHODS: We measured heart dimensions and LVM using echocardiography, and arterial stiffness using pulse wave analysis in 23 children with good glucose handling (postfeeding glucose: 3.9 to 5 mmol/L) and 21 with poor glucose handling (7.7 to 11.4 mmol/L). RESULTS: The time to pulse reflection was slightly shorter in the poorer glucose handlers (mean+/-SD: 143+/-10 vs 153+/-20 ms, P=0.04), suggestive of increased arterial stiffness. Also in this group, there were significant relationships between intraventricular septal thickness, blood pressure and body mass index, but not in the normal glucose handlers. CONCLUSIONS: We have found that normal children who are in the lowest quintile of glucose tolerance in comparison with their peers are exhibiting the first signs of arterial stiffening. In addition, we have seen the beginnings of a relationship between blood pressure, body mass index and left ventricular enlargement in this group. While these changes may not yet be clinically significant, their emergence might be further evidence of early predisposition to cardiovascular disease. 相似文献
2.
Balanced analgesia (an opioid and a nonsteroidal anti-inflammatory agent) after hysterectomy often leads to better postoperative pain outcomes. Researchers compared post-hysterectomy patients who received balanced analgesia with those who received only morphine patient-controlled analgesia, and their relationship with pain scores, ambulation, and hospital length of stay. 相似文献
3.
Marijuana components suppress induction and cytolytic function of murine cytotoxic T cells in vitro and in vivo. 总被引:3,自引:0,他引:3
T W Klein Y Kawakami C Newton H Friedman 《Journal of toxicology and environmental health》1991,32(4):465-477
Killer lymphocytes play a major role in host defense against tumors and infectious diseases. Previously, we reported that delta-9-tetrahydrocannabinol (THC) and II-hydroxy-delta-9-tetrahydrocannabinol (II-hydroxy-THC) suppressed the cytolytic activity of cultured natural killer (NK) cells. Also, we showed that the drugs appeared to be affecting a stage in the killing process subsequent to the binding of the killer cell to the target cell. In the present report, we have extended these studies to an examination of the effect of cannabinoids on the activity of cytotoxic T lymphocytes (CTLs). The cytolytic activity of CTLs generated by cocultivation with either allospecific stimulators or TNP-modified-self stimulators were suppressed by both THC and II-hydroxy-THC treatment. Allospecific CTLs generated in vivo were also inhibited by an in vitro exposure to either THC or II-hydroxy-THC, and the sensitivity of these cells to drug effects appeared to be greater than the sensitivity of the in vitro generated CTLs. Suppression of cytolytic function by THC and II-hydroxy-THC was maximal after a 4-h drug treatment, suggesting that the drug effects were inducible and therefore required a finite period of time to develop maximally. As seen in previous studies involving NK cells, drug treatment of mature CTLs appears to have little effect on the binding capacity of these cells for the target. However, the maximal killing capacity of the cells and the frequency of CTLs were significantly reduced by drug treatment. In addition to suppressing the cytolytic activity of mature effector CTLs, we also show that drug treatment inhibits both the proliferation of lymphocytes responding to an allogeneic stimulus and the maturation of these lymphocytes to mature CTLs. Similarly, CTL activity developing in vivo could be inhibited by THC injection. These results suggest that CTLs are inhibited by cannabinoids by at least two mechanisms. First, the cytolytic activity of mature killers is suppressed at some point beyond the binding to the target cell. Second, the cannabinoids appear to suppress the normal development of these mature effector cells from less mature precursor cells. 相似文献
4.
1. Six volunteers ingested 74As-labelled arsenobetaine with a fish meal. The retention and distribution of the tracer were studied by body radioactivity measurements. 2. The tracer became rapidly dispersed in soft tissues, with no major concentration in any localized organ or region. 3. In all subjects less than 1% of the ingested activity remained in the body after 24 days. 4. Any losses from the skin were minor in relation to those by other routes of excretion. 相似文献
5.
Transluminal angioplasty of the vertebral and basilar artery 总被引:4,自引:0,他引:4
R T Higashida G B Hieshima F Y Tsai V V Halbach D Norman T H Newton 《AJNR. American journal of neuroradiology》1987,8(5):745-749
Transluminal angioplasty of brachiocephalic vessels for atherosclerotic lesions is now being performed in selected cases. We have thus far treated 17 cases of vertebral artery stenosis and one case of basilar artery stenosis by intravascular balloon dilatation techniques. Clinical presenting symptoms included vertebral basilar insufficiency, repeated transient ischemic attacks (TIAs), and multiple strokes. We performed successful transluminal angioplasty in 16 patients with marked narrowing (greater than 70%) of the dominant vertebral artery from atherosclerosis. One patient with basilar artery stenosis with tandem atherosclerotic lesions was also treated by angioplasty techniques. Repeat angiography at 3- to 12-month intervals has revealed continued patency at the angioplasty site. Complications occurred in our one patient with basilar artery angioplasty, who suffered a brainstem infarction after treatment, and in one patient who had a TIA after bilateral vertebral artery angioplasty. Two other patients had residual vertebral stenosis but remained asymptomatic after the procedure. All other patients who had successful dilatation were asymptomatic at 6 months to 2 years (mean, 15 months) of follow-up. These initial studies indicate that vertebral artery angioplasty may be effective for treating high-grade atherosclerotic lesions and for improving blood flow to the posterior circulation. Angioplasty of the basilar artery is technically more difficult and has a higher degree of risk because of the many perforating branches supplying the brainstem. 相似文献
6.
Neurological signs and symptoms are common in recreational divers with decompression illness (DCI). The spectrum of neurological manifestations, temporal profile, and laboratory findings are described in a large series of 200 consecutive recreational divers treated for DCI. The Hyperbaric Medicine Unit charts of 200 recreational divers treated for DCI were reviewed and analyzed. The cohort was mainly male, with a median age of 40 years, and quite experienced, with a median of 100 prior dives. In 44 divers (22%) a rapid ascent was documented. The median time to onset of neurological symptoms was 60 minutes after surfacing. One hundred seventy-seven of 200 divers (88.5%) had at least one symptom of neurological DCI at presentation. The most common neurological manifestations were paresthesia, dysesthesia, incoordination, motor weakness, and dizziness. Paresthesias were associated with significantly younger (p = 0.003) and less experienced (p = 0.03) divers. Similar but less significant correlations were noted for dysesthesias. Female divers were significantly more likely to experience painful skin symptoms (p < 0.001). Neurological manifestations are common in recreational divers treated for DCI. Neurological DCI and paresthesias are more likely to occur in younger and less experienced divers. 相似文献
7.
The use of pseudo-first-order chemical reaction kinetics and Arrhenius thermodynamic principles in estimating the effect of temperature on shelf-life of drug solutions is described. The degradation of many drugs in aqueous solutions occurs by hydrolysis. Equations using activation energy of the hydrolysis reaction (Ea) derived from Arrhenius principles, rate constants, and temperature are used to illustrate the exponential decrease in drug shelf-life proportional to an arithmetic increase in temperature. Use of the Q value, a factor based on Ea, rate constants, and temperature change, is described. The range of Ea for pharmaceutically important degradation reactions is relatively limited; thus, near room temperature, Q values of 2-5 can be used to estimate the effect of temperature change on shelf-lives of drugs in solution. To conservatively estimate effect on shelf-life when Ea is not known, a Q value of 2 is used to predict the increase in shelf-life obtained by decreasing storage temperature, and a Q of 5 is used to predict decrease in shelf-life from increasing the temperature. Sample calculations are used to show the application of equations based on these principles to practical temperature-dependent problems regarding shelf-life. Given information about shelf-life at a certain temperature, pharmacists can estimate safe shelf-life under other temperature conditions by using these equations. 相似文献
8.
9.
F. A. Ashley B. Gibson B. Daly S. Lygo Baker J. T. Newton 《European journal of dental education》2006,10(1):10-19
The aim of this study was to explore undergraduate and postgraduate dental students' understanding of a good learning experience by using 'reflection on learning' as described by Schon. Four groups of Year 4 BDS students and one group of postgraduate students in dental public health took part in a series of focus group discussions. The responses were grouped into four broad themes (a) active, practical and positive learning; (b) interactive/together learning; (c) personal learning; (d) theory into practice. Six educational models of good learning proposed by the students are described. 相似文献
10.
Osteoclastoma of the calvarial bone of membranous origin is a rare entity. This paper presents a case of osteoclastoma of the occipital bone and a brief review of literature. 相似文献