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91.
被动吸烟对金黄地鼠致畸作用的研究 总被引:4,自引:0,他引:4
目的 采用被动吸烟方法研究香烟烟雾对金黄地鼠胚胎的致畸作用。②方法 应用被动吸烟笼具将不同妊娠时间的金黄地鼠分组进行被动吸烟 ,而后计数每组的胚胎植入数、活胎、吸收胎、死胎、畸胎及畸形数 ,并进行统计学处理。③结果 孕 1~ 6d ,7d ,9d以及 10~ 14d吸收胎加死胎的百分数比对照组略有增加 ,畸胎和畸形数无增加。而孕 8d吸收胎加死胎百分数、畸胎率均比对照组有显著增加 (χ2 =17.2 ,5 1.4,P <0 .0 0 1)。④结论 吸烟对胚胎有致畸作用。 相似文献
92.
Stephen G. Zak David Yeroushalmi William J. Long Morteza Meftah Erik Schnaser Ran Schwarzkopf 《The Journal of arthroplasty》2021,36(7):2492-2496
BackgroundIntraoperative tourniquet use in total knee arthroplasty (TKA) is a common practice which may improve visualization of the surgical field and reduce blood loss. However, the safety and efficacy associated with tourniquet use continues to be a subject of debate among orthopedic surgeons. The primary purpose of this study is to evaluate the effects of tourniquet use on pain and opioid consumption after TKA.MethodsThis is a multicenter randomized controlled trial among patients undergoing TKA. Patients were preoperatively randomized to undergo TKA with or without the use of an intraoperative tourniquet. Frequency distributions, means, and standard deviations were used to describe baseline patient demographics (age, gender, race, body mass index, smoking status), length of stay, surgical factors, visual analog scale pain scores, and opioid consumption in morphine milligram equivalents.ResultsA total of 327 patients were included in this study, with 166 patients undergoing TKA without a tourniquet and 161 patients with a tourniquet. A statistically significant difference was found in surgical time (97.87 vs 92.98 minutes; P = .05), whereas none was found for length of stay (1.73 vs 1.70 days; P = .87), postop visual analog scale pain scores (1.73 vs 1.70; P = .87), inpatient opioid consumption (19.84 vs 19.27 morphine milligram equivalents; P = .74), or outpatient opioid consumption between the tourniquet-less and tourniquet cohorts, respectively. There were no readmissions in either cohort during the 90-day episode of care.ConclusionUtilization of a tourniquet during TKA has minimal impact on postoperative pain scores and opioid consumption when compared with patients who underwent TKA without a tourniquet. 相似文献
93.
Julia M. Grottenthaler Annette Konzelmann Anette Stiegler Clemens Hinterleitner Sarah M. Bott Thomas Klag Christoph R. Werner Martina Hinterleitner Alfred Königsrainer Anil Batra Nisar P. Malek Silvio Nadalin Christoph P. Berg 《Transplant international》2021,34(11):2257-2265
Alcohol abuse after liver transplantation can seriously impact graft and patient survival. However, to date, there is no defined standard procedure to identify patients consuming alcohol after liver transplantation. The aim of this study was to analyze the diagnostic value and clinical impact of routinely measured urinary ethyl glucuronide (uEtG) – a metabolite of ethanol – in patients after liver transplantation. Data of 362 consecutive patients after liver transplantation who visited the University Hospital of Tuebingen for outpatient follow-up were analyzed. Forty-eight patients (13%) displayed positive uEtG results. The uEtG positive group contained significantly more patients with pretransplant alcoholic liver disease. However, two thirds of the uEtG positive patients had no history of pretransplant alcoholic liver disease. Several clinical parameters were significantly associated with positive uEtG. In order to enable a more cost-effective application of uEtG in the future, a clinical risk score was developed (specificity 0.95). In conclusion, routine testing for uEtG reveals a considerable percentage of patients practicing alcohol intake after liver transplantation. Application of our proposed risk score could help focusing uEtG testing on patients at risk. 相似文献
94.
95.
Bruce J. Martin 《European journal of applied physiology》1981,47(4):345-354
Summary Acute loss of sleep produces few apparent physiological effects at rest. Nevertheless, many anecdotes suggest that adequate
sleep is essential for optimum endurance athletic performance. To investigate this question, heavy exercise performance after
36 h without sleep was compared with that after normal sleep in eight subjects. During prolonged treadmill walking at about
80% of the
max, sleep loss reduced work time to exhaustion by an average of 11% (p=0.05). This decrease occurred despite doubling monetary incentives for subjects during work after sleeplessness. Subjects
appeared to fall into “resistant” and “susceptible” categories: four showed less than a 5% change in performance after sleep
loss, while four others showed decrements in exercise tolerance ranging from 15 to 40%. During the walk, sleep loss resulted
in significantly greater perceived exertion (p<0.05), even though exercise heart rate and metabolic rate (
and
) were unchanged. Minute ventilation was significantly elevated during exercise after sleep loss (p<0.05). Sleep loss failed to alter the continuous slow rises in
E and heart rate that occurred as work was prolonged. These findings suggest that the psychological effects of acute sleep
loss may contribute to decreased tolerance of prolonged heavy exercise.
Supported in part by Public Health Service grant PHS S07 RR 5371, and by Grant DAMD-17-81-C-1023 from the U.S. Army 相似文献
96.
Hawks D 《Drug and alcohol review》1993,12(1):111-113
A critique is offered of the Distilled Spirits Industry Council position paper 'Alcohol Availability'. It is argued that this position paper presents a simple-minded analysis of the complex relationship between the availability of alcohol and its consumption which pays no attention to the importance of price in determining consumption. As a consequence, it misconstrues the lessons to be drawn from the Victorian experiment in liberalization and fails to consider its implications for the incidence of alcohol related problems. 相似文献
97.
The perioperative changes in relationship between oxygen delivery (D¨O
2) and oxygen consumption (V¨O
2) were examined in forty patients who underwent coronary artery bypass grafting (CABG) without blood transfusion. Hemodilution was performed to maintain hematocrit of 19.2 ± 1.8% during cardiopulmonary bypass (CPB). Hemodynamic and metabolic parameters were measured in four stages; before CPB (stage I), after CPB (stage II), after ICU arrival (stage III), and the following day (stage IV). In each stage, there was a strong positive correlation between V¨O
2 and D¨O
2. In stage I, a decrease in D¨O
2 was met with low V¨O
2, and there was no imbalance between them (r = 0.67, P 0.01). V¨O
2 increased significantly in stage II, and this increased V¨O
2 was compensated by an increase in D¨O
2 sufficiently to meet tissue oxygen demand (r = 0.59, P 0.01). In stage III and IV, the increases in tissue oxygen requirements were met by increases in oxygen extraction ratio (r = 0.81, P 0.01, r = 0.60, P 0.01, respectively) reflected in lowered mixed venous oxygen tension and saturation. From these results, it is assumed that the adequate relationship between V¨O
2 and D¨O
2 can be maintained in the perioperative period of CABG without blood transfusion.(Mizushima A, Niimi Y: Oxygen Delivery and consumption in the perioperative period of coronary artery bypass grafting without blood Transfusion. J Anesth 4: 313–318, 1990) 相似文献
98.
对比安氟醚、七氟醚两种吸入麻醉药在腹部手术麻醉期间对机体耗氧量(VO2)的影响。方法选择择期腹部手术病30例,ASAⅠ-Ⅱ级,随机分为安氟醚(E)组和七氟醚(S)组。记录手术开始前、麻醉吸醚后5min及手术开始后30、60、90、120、150min时的吸入一呼出氧浓度差,分钟通气量,计算VO2。同时记录呼气末CO2浓度(E-TCO2),平均动脉压(MAP)、心率(HR),体温(T),最低肺泡有效 相似文献
99.
Landrigan PJ 《Maternal and child health journal》1997,1(1):61-64
Children today are exposed extensively to toxins in the environment. Prominent among these are exposures to over 70,000 synthetic chemicals, all newly developed in the past 50 years and largely untested for their hazards to children's health. Children are uniquely vulnerable to toxins, and with increasing incidence they are developing chronic, disabling, life-threatening diseases known or suspected to be of environmental origin–asthma, endocrine disruption, cancer, and the diseases caused by tobacco. Pediatricians need to consider toxic etiologies in the differential diagnosis of childhood illness. 相似文献
100.
T. B. R. J. Smith W. G. Hopkins N. A. S. Taylor 《European journal of applied physiology》1994,69(1):44-49
The position of the body and use of the respiratory muscles in the act of rowing may limit ventilation and thereby reduce maximal aerobic power relative to that achieved in cycling or running, in spite of the greater muscle mass involved in rowing. This hypothesis was investigated for three groups of male subjects: nine elite senior oarsmen, eight former senior oarsmen and eight highly trained athletes unskilled in rowing. The subjects performed graded exercise to maximal effort on a rowing ergometer, cycle ergometer and treadmill while respiratory minute volume
and oxygen consumption
were monitored continuously. The VE at a given
during intense submaximal exercise (greater than 75% of maximal
) was not significantly lower in rowing compared with that in cycling and treadmill running for any group, which would suggest that submaximal rowing does not restrict ventilation. At maximal effort,
and
for rowing were less than those for the other types of exercise in all the groups, although the differences were not statistically significant in the elite oarsmen. These data are consistent with a ventilatory limitation to maximal performance in rowing that may have been partly overcome by training in the elite oarsmen. Alternatively, a lower maximal VE in rowing might have been an effect rather than a cause of a lower maximal
if maximal
was limited by the lower rate of muscle activation in rowing. 相似文献