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41.
The efficacy of nitroglycerine, verapamil and nifedipine incontrolling post-sternotomy hypertension was compared in fourgroups of 20 patients anaesthetized with fentanyl 100 µgkg–1 undergoing elective coronary artery surgery. Vasodilatorswere started before surgery and adjusted to maintain systolicarterial pressure < 120% of pre-infusion values, the mean(±SEM) requirements being: nitroglycerine (group II)3.6±0.6 µg kg–1 min–1; verapamil groupIII) 31.1 ±2.6 µg kg–1 min1 nifedipine (groupIV) 1.7±0.2 µg kg–1 min–1 Systolicpressure decreased significantly by 5 min after starting infusionsin groups II and III. In the control group (I: no vasodilator)arterial pressure increased significantly following skin incisionand sternotomy. Pulmonary arterial and capillary wedge pressuresincreased significantly following sternotomy in groups I andIII. Heart rate increased after sternotomy in all groups, butonly reached significance in groups III and IV. There were nosignificant changes in cardiac index or vascular resistance,although the latter remained lower than pre-infusion valuesat all times in groups III and IV. The P-Q interval increasedsignificantly in group III. It is concluded that nifedipineis a suitable alternative to nitroglycerine for the controlof arterial pressure during coronary artery surgery, but verapamilis not recommended because of its negative inotropic effectand its depressant effect on A-V conduction.  相似文献   
42.
P-glycoprotein, a membrane-associated transport protein, has recently been recognised as an important element of the intestinal epithelium. This paper summarises thein vivodata on the pharmacological role of intestinal P-glycoprotein. These data show that P-glycoprotein contributes to the elimination of many drugs by mediating their direct secretion from the blood into the intestinal lumen. In addition, there is also evidence that this protein can limit oral drug absorption. Hence, inhibition of intestinal P-glycoprotein, e.g. by a reversal agent like cyclosporin A, may be a promising strategy for improving the oral bioavailability of P-glycoprotein substrate drugs. Indeed, several preclinical and clinical studies have shown that coadministration of drugs with a reversal agent can substantially increase oral drug absorption.  相似文献   
43.
目的 探讨淋巴瘤骨髓浸润患者的治疗与预后。方法 34例淋巴瘤骨髓浸润患者分为单纯化疗组、化疗+放疗组、大剂量化疗+自体干细胞移植组进行治疗,长期随访,分析其预后状况。结果 全组中位生存期为20个月;1年和3年生存率分别为76.47%和26.47%,最初疗效为完全缓解和部分缓解患者的1年和3年生存率均大于未缓解患者(P<0.05);大剂量化疗+自体干细胞移植组的3年生存率大于单纯化疗组和化疗+放疗组(P<0.05)。结论 淋巴瘤骨髓浸润患者的生存率与最初疗效有关;大剂量化疗+自体干细胞移植能提高其生存率,改善预后。  相似文献   
44.
We report on the mechanisms, the environmental changes and patient compliance with regard to conventional and new dust and mite avoidance measures to prevent allergic symptoms caused by mite allergens, taking into account both allergen contamination and the developmental success of pyroglyphid Acari. Twenty patients with persisting rhinitic complaints were selected and matched. Although the patients had performed some conventional dust and mite avoidance measures (patient compliance was 90%), the dwellings proved to be a stimulus for mite development. Moisture problems due to faulty construction and excessive moisture production were common. Since humidity conditions could not be changed at short notice, the 20 homes were subjected to the new variants of mite allergen avoidance based on intensive cleaning without (control) and with an acaricide incorporated (acaricidal cleaner [Acarosan]). After the carrying out of conventional avoidance measures, these patients still had allergic symptoms, and dust from only 23 to 52% of their textile objects was under the proposed guanine (mite faeces indicator) risk level. Only the acaricidal cleaner was able to decrease the allergenic mite load (and the burden of the patients) significantly in this 12 month period. With respect to mite-extermination, acaricidal cleaning was 88% better than intensive cleaning. Reduction of guanine was 38% better in the Acarosan treatment group. Clinical results have been reported elsewhere. A significant difference in favour of the acaricidal cleaning was seen in both subjective (as regards symptoms) and in objective data (total IgE). Another 50 patients were questioned. About 90% were willing to spend two weekends (70%), or at the most one weekend (20%) per year sanitizing the dwelling by cleaning it with the whole family. The authors of this report consider acaricidal cleaning to be a significant improvement in the management of mite-allergic diseases, such as rhinitis. Compared with the replacement of home textiles, this treatment is less expensive and more effective. Patient compliance is acceptable, but depends on acceptance by physicians and the initial motivation and consequent burden on the patient.  相似文献   
45.
The pharmacokinetics of 80 mg frusemide given orally were investigated in normal subjects using a direct HPLC method for parent drug and its acyl glucuronide conjugate. Two half-lives could be distinguished in the plasma elimination of both frusemide and its conjugate, with values of 1.25 ± 0.75 and 30.4 ± 11.5 h for frusemide and 1.31 ± 0.60 and 33.2 ± 28.0 h for the conjugate. The renal excretion rate-time profile showed two phases; the rapid elimination phase lasted from 0–15 h and the second and slow phase, from 15–96 h. During the first 15 h, 33.3 ± 4.8% of the dosed frusemide was excreted; in the remaining period 15–96 h, 4.6 ± 1.5% was excreted. In the same two periods the excretion of the glucuronide was 13.4 ± 4.7 and 1.9 ± 1.1%, respectively. The mean renal clearance of frusemide was 90.2 ± 16.9 mL min?1 during the first period and 91.5 ± 29.3 mL min?1 in the remaining period, during which the stimulation of urine production was absent. The renal clearance of the acyl glucuronide was 702 ± 221 mL min?1 in the first period, but only 109 ± 51.0 mL min?1 in the second period. The stimulated urine production in the first 6 h after administration amounted to 2260 ± 755 mL (measured urine production minus baseline value of 1 mL min?1 (360 mL). During the second or rebound period (6–96 h after drug administration), the quantity of urine was 990 ± 294 mL lower than what would have been expected from the baseline production of 5400 mL. This reduced production (0.82 mL min?1) is equivalent to an 18% reduction in the average urine flow rate of 1 mL min?1.  相似文献   
46.
Abstract. The mechanisms responsible for the decreased high density lipoprotein (HDL) cholesterol levels associated with obesity and insulin resistance are not well understood. Lecithin: cholesterol acyltransferase (LCAT) and cholesterol ester transfer protein (CETP) are key factors in the esterification of cholesterol in HDL and the subsequent transfer of cholesteryl ester towards apolipoprotein B-containing lipoproteins. Phospholipid transfer protein (PLTP) may be involved in the regulation of HDL particle size. We therefore measured the activities of LCAT, CETP and PLTP using exogenous substrate assays, as well as lipids, lipoproteins, insulin and C-peptide in fasting plasma from eight healthy obese men (body mass index >27 kg m-2) and 24 non-obese subjects. The obese men had lower levels of HDL cholesterol (P<0·05) and higher levels of plasma triglycerides (P<0·05), insulin (P<0·05) and C-peptide (P<0·01), as compared to the quartile of subjects with the lowest body mass index (BMI <22·4 kg m-2). CETP and PLTP activities were elevated in the obese men by 35% (P<0·01) and by 15% (P<0·05), respectively. LCAT activity was comparable among the quartiles. Linear regression analysis showed that CETP activity was positively correlated with body mass index (P<0·02), fasting blood glucose (P7lt;0·05) and plasma C-peptide (P<0·05). PLTP activity was positively related to body mass index (P<0·01), waist to hip circumference ratio (P<0·001), as well as to fasting blood glucose (P<0·05) and plasma C-peptide (P<0·05) It is concluded that the activities of CETP and PLTP are influenced by adiposity and possibly by insulin resistance. Elevated lipid transfer protein activities may provide a mechanism that contributes to alterations in HDL in insulin resistant states.  相似文献   
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49.
Vanishing fluid collections in interlobar fissures, associated with congestive cardiac failure, are uncommon but well-recognized. Previous studies have highlighted the occurrence of solitary vanishing ‘tumours’, but in the study reported here 7 out of 12 consecutive patients presented with more than one interlobar fluid collection simulating pulmonary tumours. In most cases a lateral radiograph confirmed the correct diagnosis and in all cases follow-up radiographs demonstrated resolution of all pleural fluid collections. In one case ultrasound was helpful. Making the correct diagnosis is very important inorder to prevent inappropriate investigations and treatment such as biopsy or surgery. It is suggested that unusual pleural fluid collections may be more common in communities where pleural disease following stab wounds or tuberculosis are more prevalent.  相似文献   
50.
A short ACTH test was performed in the six parents, and four siblings, of three cases with 17 alpha-hydroxylase deficiency. Baseline steroid levels were all normal in female heterozygotes but in males 17 alpha-hydroxyprogesterone levels were elevated. After ACTH-stimulation, plasma levels of corticosterone were elevated in five obligate heterozygotes and 18-hydroxydeoxycorticosterone levels were increased in four of them. Two of the four siblings had biochemical signs of heterozygosity. The short ACTH test appears to be an efficient method for detecting heterozygosity, but the abnormalities found are more heterogeneous than previously suggested.  相似文献   
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