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排序方式: 共有1236条查询结果,搜索用时 15 毫秒
1.
Noninvasive Intracranial Cerebral Flow Velocity Evaluation in the Emergency Department by Emergency Physicians 总被引:2,自引:0,他引:2
Michael Shafé MD Michael Blaivas MD RDMS Edmond Hooker MD Leigh Straus BS 《Academic emergency medicine》2004,11(7):774-777
Transcranial Doppler (TCD) is an accepted modality for the evaluation of cerebral blood flow velocities. OBJECTIVES: The purpose of this study was to test the feasibility of bedside TCD measurement in the emergency department (ED) with critically ill, intubated patients. METHODS: A prospective convenience sample of patients presenting to a university hospital over a two-month period underwent TCD evaluation of the middle cerebral artery. Intubated patients with head trauma and any patient requiring tracheal intubation were eligible. A 2-MHz Doppler probe was positioned over the temporal bone to acquire blood flow velocities. An emergency medicine resident and research assistant obtained measurements. Continuous TCD tracings were recorded on a video cassette recorder tape for quality assurance review and data collection. Vital signs and therapeutic interventions were also recorded. Flow velocities were measured in cm/s; the peak Resistance Index (RI) was calculated for each patient. RESULTS: A total of 30 patients were enrolled in the study. Adequate tracings were obtained in 25 patients (83%) without a disruption of resuscitation. Tracings could not be obtained in five patients; they were listed as TCD failures. However, in two of these patients, adequate flow velocity tracings were obtained after resuscitation. Four patients were evaluated during tracheal intubation. One patient was monitored successfully during cardiopulmonary resuscitation. The median time required for data acquisition was 1.9 minutes. The mean highest RI for those who expired was 0.84. For those who survived, the mean highest RI was 0.52. The difference of 0.32 was statistically significant (p = 0.04). CONCLUSIONS: Noninvasive blood flow velocity monitoring of the middle cerebral artery using TCD is feasible in the ED when performed at the bedside on intubated patients with traumatic brain injury and others during tracheal intubation and resuscitation. 相似文献
2.
3.
De Leo V; Morgante G; Lanzetta D; D'Antona D; Bertieri RS 《Human reproduction (Oxford, England)》1997,12(2):357-360
We report the results of administration of danazol after suspension of
gonadotrophin-releasing hormone analogue (GnRHa) therapy for uterine
myomas. A total of 21 women with uterine myomas was treated with 100 mg
danazol for 6 months after GnRHa therapy. Uterine volume and endocrine
status were monitored monthly by ultrasound and assay of plasma
gonadotrophins, oestradiol and progesterone. The results show a rebound of
uterine volume about 30% less than in controls at the end of danazol
therapy. Menstrual cyclicity returned after 65 +/- 3 days in 16 subjects
and five patients remained amenorrhoeic. Hormone assays confirmed renewed
ovarian function in the women whose menstrual periods returned. Bone
mineral content was substantially reduced during GnRHa treatment but
improved significantly during danazol therapy even in the women who
remained amenorrhoeic. These results show the utility of danazol in
prolonging the therapeutic effects of GnRHa. The mechanism by which danazol
inhibits rebound of uterine volume may be due to its antiprogesterone
effects on uterine myomas.
相似文献
4.
5.
S P Hooker S F Figoni M M Rodgers R M Glaser T Mathews A G Suryaprasad S C Gupta 《Journal of rehabilitation research and development》1992,29(3):1-11
This study determined the metabolic and hemodynamic responses in eight spinal cord injured (SCI) quadriplegics (C5-C8/T1) performing subpeak arm crank exercise (ACE) alone, subpeak functional electrical stimulation leg cycle exercise (FES-LCE) alone, and subpeak FES-LCE concurrent with subpeak ACE (hybrid exercise). Subjects completed 10 minutes of each exercise mode during which steady-state oxygen uptake (VO2), pulmonary ventilation (VE), heart rate (HR), cardiac output (CO), stroke volume (SV), mean arterial pressure (MAP), arteriovenous oxygen difference (a-v O2 diff), and total peripheral resistance (TPR) were determined. Although mean VO2 for both ACE alone and FES-LCE alone was matched at 0.66 l/mi, individualized power outputs ranged from 0-30 W (mean = 19.4 +/- 1.3) and 0-12.2 W (mean = 2.3 +/- 0.6), respectively. Hybrid exercise elicited significantly higher VO2 (by 54 percent), VE (by 39-53 percent), HR (by 19-33 percent), and CO (by 33-47 percent), and significantly lower TPR (by 21-34 percent) than ACE or FES-LCE performed alone (P less than or equal to 0.05). Stroke volume was similar between hybrid exercise and FES-LCE alone, and these two exercise modes evoked a significantly higher SV (by 41-56 percent) than during ACE alone. These data clearly demonstrate that hybrid exercise creates a higher aerobic metabolic demand and cardiac-volume load in SCI quadriplegics than either subpeak levels of ACE or FES-LCE performed separately. Therefore, hybrid exercise may provide more advantageous central cardiovascular training effects in quadriplegics than either ACE or FES-LCE alone. 相似文献
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7.
The purpose of this study was to determine peak aerobic power and associated physiological responses in highly competitive spinal cord injured (SCI) paraplegic road racers. Seven (6 male and one female) active paraplegic (lesions T4-T12) road racers and 9 healthy untrained able-bodied males performed continuous graded arm crank ergometer tests to exhaustion for determinations of peak power output (PO), oxygen uptake (VO2), pulmonary ventilation (VE), heart rate (HR), and respiratory exchange ratio (RER). Compared to able-bodied subjects, male paraplegic road racers elicited significantly (p less than or equal to .05) higher mean (+/- SD) peak levels of PO (141.6 +/- 8.8 vs 111.4 +/- 27.7 W), absolute VO2 (2.72 +/- .52 vs 2.22 +/- .381/min), and VO2 per unit of body weight (43.06 +/- 7.4 vs 30.33 +/- 4.3 ml/kg/min). Although peak HR (180.3 +/- 9.5 vs 173.2 +/- 8.5 bpm) and VE (92.8 +/- 17.2 vs 74.6 +/- 20.3 l/min) tended to be higher for male paraplegic road racers than able-bodied subjects, the differences were not statistically significant. The female paraplegic road racer achieved the highest peak levels of PO (119 W) and VO2 (1.99 l/min; 38.0 ml/kg/min) reported to date for wheelchair-dependent women. These data suggest that intense physical training via wheelchair propulsion can markedly enhance upper body cardiovascular fitness in SCI paraplegics. However, the correlational analysis between 10 km time and peak VO2 was nonsignificant (p greater than .05) indicating that factors other than peak upper body aerobic power may influence wheelchair road racing performance. 相似文献
8.
Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm). 相似文献
9.
The authors report the clinical and laboratory findings of a patient who had severe immune hemolytic anemia due to hydrochlorothiazide (HCTZ). In this case, the HCTZ antibody reacted not only with other thiazide and thiazide-like drugs, but also with a chemically unrelated diuretic, ethacrynic acid. These results indicate that HCTZ antibody activity is not restricted solely to the thiazides and imply that therapy with any of the reactive drugs would be contraindicated for this patient. The serologic screening for drug reactivity may be useful for selecting alternative therapy for patients with drug-induced immune hemolytic anemia. 相似文献
10.
Inhibition of 2-nitropropane-induced rat liver DNA and RNA damage by benzyl selenocyanate 总被引:5,自引:2,他引:3
We observed that pretreatment of male F344 rats with benzyl selenocyanate,
a versatile organoselenium chemopreventive agent in several animal model
systems, decreases the levels of DNA and RNA modifications produced in the
liver by the hepatocarcinogen 2- nitropropane. To clarify the mechanisms
involved, we pretreated male F344 rats with either benzyl selenocyanate,
its sulfur analog benzyl thiocyanate, phenobarbital or cobalt
protoporphyrin IX; the latter is a depletor of P450. We then determined (1)
the ability of liver microsomes to denitrify 2-nitropropane, (2) effects on
2-nitropropane- induced liver DNA and RNA modifications and (3) amount of
nitrate excreted in rat urine following administration of the carcinogen.
Pretreatment with benzyl selenocyanate or phenobarbital increased the
denitrification activity of liver microsomes by 217 and 765%, respectively,
increased liver P4502B1 by 31- and 435-fold, respectively, decreased the
levels of 2-nitropropane-induced modifications in liver DNA (29-70% and
17-30%, respectively) and RNA (67-85% and 30-50%, respectively), and
increased the 24-h urinary excretion of nitrate by 157 and 209%,
respectively. Pretreatment with benzyl thiocyanate had no significant
effect on any of these parameters. Pretreatment with cobalt protoporphyrin
IX decreased liver P4502B 1 by 87%, decreased the denitrification activity
of liver microsomes by 76%, decreased the 24 h urinary excretion of nitrate
by 88.5%, but increased the extent of 2-nitropropane-induced liver nucleic
acid modifications by 17-67%. These results indicate that the metabolic
sequence from 2-nitropropane to the reactive species causing DNA and RNA
modifications does not involve the removal of the nitro group. Moreover,
they suggest that benzyl selenocyanate inhibits 2-NP-induced liver nucleic
acid modifications in part by increasing its detoxication through induction
of denitrification, although it is evident that other mechanisms must also
be involved.
相似文献