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41.
Summary Pre-incubation of human platelets with nifedipine in vitro or treatment of normal volunteers with nifedipine, 30 mg daily for one week, did not alter ADP induced aggregation measured by whole blood aggregometry. 6-oxo-Prostaglandin F1 remained undetectable in plasma following oral administration of nifedipine to normal volunteers. The hypotensive response to intravenous nifedipine administration was similar in spontaneously hypertensive rats pretreated with indomethacin or placebo. These results conflict with previous reports that nifedipine alters platelet aggregation and prostaglandin metabolism.  相似文献   
42.
BackgroundThe opioid crisis in the United States may be exacerbated by the COVID-19 pandemic. Increases in opioid use, emergency medical services (EMS) runs for opioid-related overdoses, and opioid overdose deaths have been reported. No study has examined changes in multiple naloxone administrations, an indicator of overdose severity, during the COVID-19 pandemic.ObjectiveThis study examines changes in the occurrence of naloxone administrations and multiple naloxone administrations during EMS runs for opioid-related overdoses during the COVID-19 pandemic in Guilford County, North Carolina (NC).MethodsUsing a period-over-period approach, we compared the occurrence of opioid-related EMS runs, naloxone administrations, and multiple naloxone administrations during the 29-week period before (September 1, 2019, to March 9, 2020) and after NC’s COVID-19 state of emergency declaration (ie, the COVID-19 period of March 10 to September 30, 2020). Furthermore, historical data were used to generate a quasi-control distribution of period-over-period changes to compare the occurrence of each outcome during the COVID-19 period to each 29-week period back to January 1, 2014.ResultsAll outcomes increased during the COVID-19 period. Compared to the previous 29 weeks, the COVID-19 period experienced increases in the weekly mean number of opioid-related EMS runs (25.6, SD 5.6 vs 18.6, SD 6.6; P<.001), naloxone administrations (22.3, SD 6.2 vs 14.1, SD 6.0; P<.001), and multiple naloxone administrations (5.0, SD 1.9 vs 2.7, SD 1.9; P<.001), corresponding to proportional increases of 37.4%, 57.8%, and 84.8%, respectively. Additionally, the increases during the COVID-19 period were greater than 91% of all historical 29-week periods analyzed.ConclusionsThe occurrence of EMS runs for opioid-related overdoses, naloxone administrations, and multiple naloxone administrations during EMS runs increased during the COVID-19 pandemic in Guilford County, NC. For a host of reasons that need to be explored, the COVID-19 pandemic appears to have exacerbated the opioid crisis.  相似文献   
43.
BackgroundThe aim of the study is to determine if barium esophagram (BE) alone is sufficient to diagnose esophageal dysmotility when compared to the gold standard, high-resolution manometry (HRM).MethodsThis is a retrospective review of patients that underwent laparoscopic fundoplication by two surgeons at a single institution from 10/1/2015-6/29/2019. Patients with large paraesophageal hernias and patients without both BE and HRM were excluded.ResultsForty-six patients met the inclusion criteria. BE was found to be concordant with HRM for esophageal motility in only 21 patients (46%). Setting HRM as the gold standard, BE had a sensitivity of 14% (95% CI: 5%–35%), specificity of 72% (95% CI: 52%–86%), PPV of 30% (95% CI: 11%–60%), and NPV of 50% (95% CI: 35%–66%). The accuracy was 46%, while a McNemar test showed p = 0.028.ConclusionTraditional BE should not be used in place of HRM for assessing pre-operative motility in patients undergoing anti-reflux surgery.  相似文献   
44.
A representative sample of 406 U.S. Navy commands, including all medical treatment facilities, was surveyed in 1990 about their activities and programs to prevent the use of tobacco and promote smoking cessation during the preceding year. The vast majority of Navy commands (86 percent) provided some type of tobacco cessation educational materials or programs. However, the most common activities typically were rated as only "somewhat useful" in helping to curb tobacco use. Almost one-half of all commands offered psychological or behavioral cessation programs. Survey respondents estimated that approximately one-third of those persons who attended such a program stopped their tobacco use and nearly one-half reduced their tobacco use as a result of the program. Over-the-counter smoking cessation aids were not widely available at Navy exchange stores, individual commands, or medical treatment facilities. Furthermore, only 61 percent of all commands reported that they had a written policy or instruction regarding tobacco use. Only about one-third of medical treatment facilities had a routine system for identifying tobacco users by glancing at their medical records. However, it was estimated that 80 percent of medical treatment facility physicians routinely asked their patients about their tobacco use. The authors discuss the need for a more active Navy approach in prevention and cessation efforts and a routine system for identifying tobacco users from their medical records. In addition, inequities in cessation efforts were found among command subgroups.  相似文献   
45.
Watson’s syndrome is an uncommon genetic disorder whose features include mental retardation and pulmonary valvular stenosis. The purpose of this report is to describe one management strategy used successfully to anaesthetize a woman with this disorder who presented for Caesarean section. Epidural anaesthesia using 0.5% bupivacaine without epinephrine in 2–3 ml boluses to a total dose of 15 ml was administered over 30 min. Invasive haemodynamic monitoring in the form of arterial and central venous catheters were used to guide therapy and help ensure maternal and fetal well-being. Intravenous ketamine in doses of 10–20 mg every five minutes to a total dose of 245 mg (4.5 mg · kg?1) was used to overcome the patient’s uncooperative nature and facilitate invasive procedures. Postoperative analgesia was provided using 3 mg epidural morphine. The patient was observed in the intensive care unit for the first postoperative day and experienced an uncomplicated intra- and postoperative course. We conclude that this technique represents a safe and effective method for anaesthetizing patients with this complicated problem for Caesarean section.  相似文献   
46.
OBJECTIVE: The purpose of this study was to determine if overnight energy expenditure, the lowest energy expenditure sustained for 60 min during the night, measured and predicted basal metabolic rate are equivalent. DESIGN: Overnight energy expenditure (ON-EE), the lowest energy expenditure sustained for 60 min during sleep (LS-EE) and basal metabolic rate (BMR) were measured two to seven times in a room-sized indirect calorimeter in 69 adult subjects. Subjects' gender, age, weight and height were also used to predict BMR (FAO/WHO/UNU, 1985) (BMR-WHO). SETTING: Beltsville Human Nutrition Research Center, Beltsville, MD, USA. RESULTS: The results from calorimetry measurements (mean +/- s.d.) included: ON-EE (6.87 +/- 0.99 MJ/d), LS-EE (6.18 +/- 0.94 MJ/d) and BMR (6.87 +/- 0.99 MJ/d). Predicted BMR mean was: BMR-WHO, 6.95 +/- 1.03. The mean within-subject difference for the calorimetry measurements were: ON-EE, 0.21 MJ/d; LS-EE, 0.16 MJ/d; and BMR, 0.34 MJ/d. Results indicate there was no significant difference between ON-EE, BMR and BMR-WHO. LS-EE was significantly lower (P < 0.0001) than ON-EE, BMR and BMR-WHO. CONCLUSION: These results indicate that while metabolic rate drops significantly below BMR during sleep, overnight metabolic rate and BMR are equivalent.  相似文献   
47.
48.

Purpose

To study the haemodynamic effects of intrathecal meperidine, administered either alone or mixed with bupivacaïne.

Methods

We studied 42 Chinese patients, aged 59–87 yr, scheduled for transurethral bladder or prostate surgery, randomized into three equals groups, that received either meperidine 0.8 mg · kg?1 meperidine 0.4 mg · kg?1 plus 1.5 ml of 0.5% heavy bupivacaïne or 3 ml of heavy bupivacaïne 0.5%. Non-invasive systolic (SAP) and mean (MAP) arterial pressures, central venous pressure and cardiac index, stroke index and heart rate (HR) measured by the BoMed NCCOM3-R7S bioimpedance device, were recorded over the first 25 min. Systemic vascular resistance index (SVRI) was derived. Onset of sensory and motor block was also measured. Decreases in MAP of 25% were treated with colloid and metaraminol. Results: The onset of block was slower in the meperidine group (P < 0.05). Decreases in SAP, MAP and SVRI (all; P < 0.001) occurred within five minutes in all three groups. The HR was increased in the bupivacaïne group (P = 0.03), but bradycardias treated with atropine occurred in six patients receiving meperidine and four patients receiving the mixture. Six patients receiving meperidine and two patients receiving the mixture required general anaesthesia for inadequate block. The incidence of nausea and vomiting was higher in the patients receiving meperidine (P < 0.05). No other complications were encountered.

Conclusions

Intrathecal meperidine used alone or mixed with bupivacaïne has no intra-operative advantage over heavy bupivacaïne 0.5%.  相似文献   
49.
Last year, the AHRA Southern Region Statistical Resource Committee surveyed its members about their departments' film loan policies. This article presents the results of that survey, providing information on such topics as lending original films, charging for copies, and protecting against liability. While there doesn't seem to be a standard approach to releasing films, survey findings suggest that liability issues and cost factors are of great concern in determining which policy should be adopted.  相似文献   
50.
Part I of this AHRA membership survey reports on information relating to staff utilization in diagnostic radiology. The average volume of procedures per full-time-equivalent staff is provided for technologists, physicians, clerical staff and transporters. Part II, to be published in the Summer issue, will provide reports on specialty areas in radiology.  相似文献   
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