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101.
In a retrospective study the prognostic significance of nuclear DNA content was investigated, as measured by flow cytometry, of the tumor specimens from 212 women with nonpretreated FIGO stage IB and II cervical cancer. One-hundred and thirty cases (62%) were found to be diploid, whereas 82 (38%) were aneuploid. Univariate analysis of the follow-up data showed an increased relative risk (RR) for recurrence free survival (RFS) for stage II tumors (RR = 1.87, 95% CI: 1.13–3.10, P = 0.015) and for age (RR = 1.52, 95% CI: 0.66–3.52 and RR = 2.35, 95% CI: 1.19–4.65, P = 0.032). Ploidy showed a relative risk of 1.33 (95% CI: 0.83–2.13, NS). In addition, univariate analysis of overall survival (OS) revealed similar results. For the subgroup of patients with primary surgery ( n = 151), positive pelvic nodes (RR = 5.38, 95% CI: 2.70–10.71, P = 0.0001) and parametrial extension (RR = 2.53, 95% CI: 1.24–5.17, P = 0.011) were significant factors for OS after univariate analysis, the estimated effects on RFS were slightly smaller. Multivariate analysis of RFS for the whole study population showed age, histologic grade and stage with a slightly increased risk, but no effect was significant. Ploidy with an RR of 0.97 (95% CI: 0.58–1.62) seems to have no influence on prognosis. For the subgroup with primary surgery, ploidy again failed statistical significance with an RR of 1.20 (95% CI: 0.58–2.49). Our results suggest that abnormalities of the nuclear DNA content in this homogeneous group of patients are associated with clinical and morphological prognosticators, however, ploidy is not an independent prognostic factor for RFS, or for the whole study population or for the subgroup with primary surgery.  相似文献   
102.
Da-Nian Zhu, Long-Mei Xue, Peng Li. Effect of central muscarine receptor blockade. with DKJ-21 on the blood pressure and heart rote in stress-induced hypertensive rats.

The experiments were performed on Wistar or Sprague-Dawley rats of both sexes divided at random into stress and control groups. The rats in the stress groups were put into cages and subjected to electric foot-shocks and noises for 9-15 days, which caused an increase in blood pressure (BP) and heart rate (HR). In hypertensive rats DKJ-21 (4mg/lml) was injected intravenously (i.v.), and 0.5-1.0h after administration the BP and HR dropped from the high level to normotensive level. In normotensive rats, however, administration of DKJ-21 had no effect on BP or HR. In separate groups of normotensive rats, pretreatment of DKJ-21 (4 mg/l ml, i.v.) blocked the pressor and tachycardiac effect induced by microinjection of physostigmine (0.4μg/0.1 /μl/site), corticosterone (40μg/0.1μl/site) or aldosterone (40 μg/0.1 μl/site) into the rostral ventrolateral medulla (rVLM). Furthermore, DKJ-21 also attenuated the enhancement of the pressor response to stimulation of the defense area in the midbrain, which was induced by microinjection of drugs (mentioned above) into the rVLM. These results indicate that i.v. DKJ-21 can selectively block the muscarinic receptors in the rVLM in stress-induced hypertensive rats, which suggests that abnormal enhancement of cholinergic mechanism in the rVLM may be related to hypertensive effects of corticoids in this area.  相似文献   
103.
The basilar artery is the only large artery in which two flows merge, and this is reflected in the flow downstream. We report quantitative flow — velocity measurements with a phase-based MR technique, i.e. the Fourier velocity encoding method, in the basilar artery of a volunteer. To our knowledge, this has not previously been performed successfully. A comparison is made with the results of flow velocity measurements in the basilar artery with transcranial Doppler ultrasonography; the techniques agreed very well. Although Doppler ultrasonography is still most widely used, no information on the flow rate and the flow velocity distribution in the basilar artery can be provided. MR flow measurement techniques appear promising when detailed information on the flow velocity distribution and flow rate is needed.  相似文献   
104.
In 10 patients subjected to craniotomy for supratentorial cerebral tumours in neurolept anaesthesia, cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2) were measured twice peroperatively by a modification of the Kety & Schmidt technique, using 133Xe. The relative CO2 reactivity was assessed indirectly as the % change of the arteriovenous oxygen difference (AVDO2) per mm change in PaCO2. The patients were premedicated with diazepam 10-15 mg perorally. For induction, thiopentone 4-6 mg/kg, droperidol 0.2 mg/kg and fentanyl 5 micrograms/kg were used, and for maintenance N2O 67% and fentanyl 4 micrograms/kg/h. During the first flow measurement the median and range of CBF was 30 ml/100 g/min (range 17-45), of AVDO2 8.0 vol % (range 4.1-9.5), and of CMRO2 2.28 ml O2/100 g/min (range 1.57-2.84). During the second CBF study, AVDO2 increased to 9.3 vol % (range 3.4-11) (P less than 0.05), and CMRO2 increased to 2.51 ml O2/100 g/min (range 1.88-3.00) P less than 0.05, while CBF was unchanged. The CO2 reactivity was present in all studies, median 1.8%/mmHg (range 0.5-15.1). The correlation coefficients between jugular venous oxygen tension/saturation, respectively, and CBF were high at tensions/saturations exceeding 4.0 kPa and 55%, indicating that hyperperfusion is easily unveiled by venous samples from the jugular vein during this anaesthesia.  相似文献   
105.
This study was conducted to determine the occurrence of menstrual-linked asthma (MLA) in India in 100 consecutive female asthmatics in the reproductive age group. The patients were required to respond to a questionnaire concerning the relationship between their asthma and the menstrual cycle. Twenty-three patients had subjective perception of deterioration in symptoms of asthma in relation to the menstrual cycle. Ten patients from both groups were also required to maintain a daily peak expiratory flow rate (PEFR) diary for 2 consecutive menstrual cycles. The mean total duration of illness in patients with MLA was significantly longer than in patients without cyclic exacerbation. Cough and breathlessness were also significantly more severe as was the disease. This was evidenced by the more frequent emergency room visits and hospitalizations in these patients. Menstrual-linked worsening of asthma was most common in the premenstrual week (17 patients). In 8 of these 17 patients, this phenomenon continued to occur during the menstrual week also. Interestingly, 1 patient complained of deterioration of asthma 2 days after menstruation was over. Such an observation is yet to be recorded. Fourteen patients reported an increase in symptoms with almost every cycle while 3 had worsening related to specific season only. Sixteen patients often required extra medication during the premenstrual and/or menstrual weeks. A significant association was also observed between severity of premenstrual syndrome and MLA. The mean PEFR values over 2 cycles revealed a significant fall in the morning as well as evening values in the premenstrual and menstrual weeks as compared to the midcycle week in patients with MLA. This fall was maximal in the premenstrual week. Such a fall was not observed in asthmatics without menstrual exacerbation of symptoms. MLA was detected in about a fourth of the female asthmatics in India and it appears to represent a more severe form of the disease. This study also documented that MLA was associated with an increase in airway resistance and was not simply due to an increased perception of symptoms during the premenstrual or menstrual weeks.  相似文献   
106.
Summary Changes in regional cerebral blood flow in anaesthetized pigs with an induced focal cerebral contusion were studied before and after two grades of hyperventilation. A reduction in arterial tension of CO2 with 0.70mmHg and a further reduction of 0.55mmHg did not change the CO2 reactivity. Reactivity in both injured and macroscopically normal regions was the same, revealing an average of 39.3% flow change per kPa change in CO2 tension. Regions with low flow after the contusion had an equally big reduction apparently leading to hypoxia because global metabolic rate was unchanged.  相似文献   
107.
The effects of two H2-receptor antagonists, famotidine and cimetidine, on the plasma levels of epidurally administered lignocaine were studied. Group A (n = 20) received famotidine 20 mg orally the night before surgery and 20 mg intramuscularly 60 minutes before induction of anaesthesia. Group B (n = 15) received cimetidine 200 mg orally the night before the surgery and 400 mg orally 60 minutes before the anaesthetic induction. Group C (n = 20) received neither famotidine nor cimetidine and served as controls. Twelve millilitres of 2.0% lignocaine with adrenaline 1:200,000 was injected into the epidural space in all patients, after the establishment of general anaesthesia with nitrous oxide, oxygen, and enflurane (0.3-0.5%). The patients who received cimetidine showed significantly higher plasma concentrations of lignocaine compared with either group A or group C at all investigation times (p less than 0.01). The mean peak plasma concentrations were 2.4 (SEM 0.1), 3.2 (SEM 0.2) and 2.3 (SEM 0.1) micrograms/ml in group A, B, and C, respectively. This study suggests that famotidine is preferable to cimetidine for control of gastric acidity before the use of lignocaine as the epidural anaesthetic.  相似文献   
108.
研究消炎痛及乙胺嗪对家兔肺、脑血管和大鼠脑微动脉缺氧反应的影响。发现吸入10%氧使家兔肺血管阻力(PVR)增加,脑血管阻力(CVR)降低,大鼠脑微动脉扩张。用消炎痛明显增强家兔缺氧性肺、脑血管反应。△PVR%由用药前26.6±16.7%增至44.2±7.7%;△CVR%则由一12.9±4.5%减至-30.7±4.7%;大鼠微动脉直径增大率(△D%)由用药前28.2±2.0%增至41.3±5.8%;用乙胺嗪则使缺氧时△PVR%由 84.6±18.1%降至 23.8±8.5%;△CVR%由-16.7±4.5%变为 6.9±2.8%;△D%由 29.7±5.8%减至 25.6±5.0%。结果表明前列腺素在缺氧性肺血管收缩反应及脑血管扩张反应中起调节作用,而白三烯则在缺氧性肺血管收缩反应中起介导作用。  相似文献   
109.
Summary. Eleven normotensive diabetics with noninsulin-dependent diabetes mellitus (NIDDM) (mean age 52.5 SD 8.2 years) and 11 controls (mean age 47.4 SD 8.9 years) had their ambulatory blood pressure and heart rate recorded non-invasively by the Oxford Medilog System in standard hospital conditions. The results were averaged as hourly means of systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial blood pressure (MAP), and heart rate (HR) for the 24-h period and similarly for the ‘awake’ period (14.16 h) and the ‘asleep’ period (8–10 h). Hourly means for diabetics and controls showed no differences in blood pressure and heart rate over the 24 h. During sleep, control subjects showed a significant drop in SBP (P < 0.001), DBP (P < 0.001), MAP (P < 0.001) and HR (P < 0.001). However, this nocturnal dip in blood pressure could not be demonstrated in the diabetic group. Blood pressure variability was significantly increased in diabetics compared to controls during waking hours (P < 0.01). These results indicate that in noninsulin-dependent diabetics during sleep there is loss of the nocturnal dip of BP seen in normal subjects, and they have increased BP variability. These may be contributing factors to the development of hypertension and the accelerated target organ damage (TOD) seen in diabetes.,  相似文献   
110.
Global and regional cerebral blood flow (CBF) were evaluated with single photon emission computerized tomography (SPECT) utilizing both 133Xenon (133Xe) (47 subjects, 47–82 years old) and 99Tc-hexamethylpropyleneamine oxime (99Tc-HMPAO) (27 subjects, 47–80 years old). The 133Xe results showed: among total subjects, no age-related decline in global CBF, but a significant regional decline in the occipital lobe (p < 0.05); among men, significant age-related declines in global, frontal, temporal, occipital and right hemisphere CBF (all p < 0.05); among women, no age-related decline in global or regional CBF. The 99Tc-HMPAO results showed no age-related decline in either global or regional perfusion among total subjects, men or women. These results suggest that age-related global and regional (including frontal lobe) CBF declines do not occur in healthy control subjects after the age of 45 years. However, gender differences in age-related CBF changes warrant further study.  相似文献   
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