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31.
The crude chloroform bark extract of Piper caninum (Piperaceae) exhibits antibacterial activity against the Gram-positive bacteria, Bacillus cereus, Staphylococcus aureus, and Streptococcus pneumoniae. The antibacterial agents in this extract have been isolated using bioactivity-directed chromatographic techniques and identified by NMR spectroscopy as (+)-bornyl p-coumarate and bornyl caffeate. A single-crystal X-ray structure has been carried out on (+)-bornyl p-coumarate. The compound crystallizes in the orthorhombic space group P2(1)2(1)2(1) (#19) with a = 12.659(4), b = 13.281(4), and c = 10.177(3) A. Fullmatrix least-squares refinement converged at R = 0.047, and Rw = 0.058.  相似文献   
32.
Phenylethanol was given at different levels (432, 43, or 4.3 mg/kg) by gavage to pregnant Long-Evans rats during the "critical period" of organogenesis. Examination of offspring revealed adverse reproductive and teratogenic effects in a dose-related manner. Intrauterine growth retardation occurred at levels of 432 and 4.3 mg/kg. Embryolethality was 18% at 43 mg/kg and 10% at 4.3 mg/kg. Malformations occurred in the following sequence: 100% at 432 mg/kg; 93% at 43 mg/kg, and 50% at 4.3 mg/kg. Noteworthy dose-related teratogenic effects of phenylethanol in offspring manifested themselves in increased incidences of malformed eyes, neural-tube defects, hydronephrosis, and limb defects.  相似文献   
33.
BACKGROUND. The elderly are the fastest growing segment of the population, and this will place additional burdens on the healthcare system. It is therefore valuable to study the elderly who have reached their later years relatively free of disease and in good health. METHODS. Health locus of control, self-efficacy beliefs, and lifestyle behaviors were studied in a sample of 57 healthy elderly subjects. Subjects completed the Multidimensional Health Locus of Control Scale, Self-Efficacy Scale, and Healthstyle Self-Test for Seniors. RESULTS. Most of the subjects were characterized by an internal health locus of control belief (91.2%), high generalized self-efficacy (57.9%), and good health behaviors. As hypothesized, positive relationships were found among these variables. DISCUSSION. Individuals with an internal health locus of control and high generalized self-efficacy are more likely to benefit from a health education program than those with an external locus of control and low self-efficacy. Health educators can better serve their clients by evaluating these parameters when developing programs.  相似文献   
34.
One hundred and four preterm infants were studied during the first few months of life in the Special Care Baby Unit of Addenbrooke's Hospital, Cambridge, United Kingdom. Previously, it had been the daily practice within the Unit to give a 1 mg oral supplement of folate (in the form of pteroylglutamic acid), once the infants had commenced full enteral feeding. At least one blood sample was obtained from 70 infants before oral folate supplementation was started. In these, the plasma folate levels fell progressively from a median value of 45 g/l to a median of 12 g/l, by the 2nd–3rd week of life. Once started on the oral supplement, 83 of the infants provided at least one blood sample. The plasma folate level of these infants rose immediately to a median value of 300 g/l and a maximum of 1000 g/l. Within individuals, these plasma folate levels decreased progressively following the introduction of the supplement, despite continuing daily supplementation. In a typical baby this decrease appeared to be explained by an increase in body-size, i.e. dilution of the folate into a larger pool. The implications of this level of supplementation are discussed, and in the light of our observations we suggest that daily supplementation in the range, 0.05–0.2 mg folate may be preferable for well preterm infants.  相似文献   
35.
BACKGROUND AND PURPOSE: Intravenous tissue plasminogen activator (tPA) administered within 3 hours of symptom onset is the first available effective therapy for acute ischemic stroke (AIS). Few data exist, however, on its use in very elderly patients. We examined the characteristics, complications, and short-term outcome of AIS patients aged >/=80 years treated with tPA. METHODS: Patients aged >/=80 years (n=30) were compared with counterparts aged <80 years (n=159) included in the tPA Stroke Survey, a US retrospective survey of 189 consecutive AIS patients treated with intravenous tPA at 13 hospitals. RESULTS: Risk of intracerebral hemorrhage (fatal, symptomatic, and total) was 3%, 3%, and 7% in the elderly age group and 2%, 6%, and 9%, respectively, in their younger counterparts (P=NS for all comparisons). Likelihood of favorable outcome, defined as modified Rankin score 0 to 1, National Institutes of Health Stroke Scale score /=80 years was identified.  相似文献   
36.
37.
PURPOSE: The epothilones are a novel class of nontaxane microtubule-stabilizing agents. BMS-247550 is a semisynthetic analog of the natural product epothilone B. We conducted a phase I study administering BMS-247550 as a 1-hour intravenous infusion daily for 5 consecutive days every 21 days. PATIENTS AND METHODS: Twenty-one patients received BMS-247550 without filgrastim in the first cycle. An additional six patients were enrolled at a starting dose of 8 mg/m2/d with filgrastim support. Twenty-one of the 27 patients had received prior paclitaxel, docetaxel, or both. RESULTS: One hundred seven cycles were administered to 27 patients. The maximum-tolerated dose was 6 mg/m2 of BMS-247550 administered as a 1-hour intravenous infusion daily for 5 consecutive days every 21 days. Dose-limiting toxicity at a dose of 8 mg/m2/d was neutropenia with or without filgrastim support. Nonhematologic grade 3 toxicities included fatigue (seven cycles), stomatitis (two cycles), and anorexia (one cycle). The mean terminal half-life of BMS-247550 was 16.8 +/- 6.0 hours, the volume of distribution at steady-state was 798 +/- 375 L, and the clearance was 712 +/- 247 mL/min. Objective responses were observed in patients with breast, cervical, and basal cell cancer. Reductions in CA-125 levels were noted in patients with ovarian cancer. CONCLUSION: The recommended phase II dose of BMS-247550 on the daily schedule for 5 days is 6 mg/m2/d. Neutropenia was dose limiting, but higher doses were tolerated by a large fraction of patients with filgrastim support. Peripheral neuropathy was mild, even after multiple cycles of therapy, and was not dose limiting.  相似文献   
38.
BACKGROUND: Acute renal failure (ARF) requiring dialysis after coronary artery bypass grafting (CABG) occurs in 1 to 5% of patients and is independently associated with postoperative mortality, even after case-mix adjustment. A risk-stratification algorithm that could reliably identify patients at increased risk of ARF could help improve outcomes. METHODS: To assess the validity and generalizability of a previously published preoperative renal risk-stratification algorithm, we analyzed data from the Quality Measurement and Management Initiative (QMMI)1 patient cohort. The QMMI includes all adult patients (N = 9498) who underwent CABG at 1 of 12 academic tertiary care hospitals from August 1993 to October 1995. ARF requiring dialysis was the outcome of interest. Cross-validation of a recursive partitioning algorithm developed from the VA Continuous Improvement in Cardiac Surgery Program (CICSP) was performed on the QMMI. An additive severity score derived from logistic regression was also cross-validated on the QMMI. RESULTS: The CICSP recursive partitioning algorithm discriminated well (ARF vs. no ARF) in QMMI patients, even though the QMMI cohort was more diverse. Rates of ARF were similar among risk subgroups in the CICSP tree, as was the overall ranking of subgroups by risk. Using logistic regression, independent predictors of ARF in the QMMI cohort were similar to those found in the CICSP. The CICSP additive severity score performed well in the QMMI cohort, successfully stratifying patients into low-, medium-, high-, and very high-risk groups. CONCLUSIONS: The CICSP preoperative renal-risk algorithms are valid and generalizable across diverse populations.  相似文献   
39.
AIMS: To study the effect of prone and supine sleep on infant behaviour, peripheral skin temperature, and cardiorespiratory parameters to aid understanding of why prone sleeping is associated with an increased risk of sudden infant death syndrome. METHODS: Of 33 enrolled infants, 32 were studied at 2.5 and 28 at 5 months of age. A computer aided multichannel system was used for polysomnographic recordings. Behaviour was charted separately. RESULTS: Prone REM (active) sleep was associated with lower frequencies of short arousals, body movements and sighs, and a shorter duration of apnoeas than supine REM sleep at both ages. At 2.5 months there were less frequent episodes of periodic breathing during prone sleep in non-REM (quiet) and REM sleep. Heart rate and peripheral skin temperature were higher in the prone position during both sleep states at both ages. CONCLUSIONS: The observation of decreased variation in behaviour and respiratory pattern, increased heart rate, and increased peripheral skin temperature during prone compared with supine sleep may indicate that young infants are less able to maintain adequate respiratory and metabolic homoeostasis during prone sleep.  相似文献   
40.
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