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11.
Assessment of completeness of vagotomy has always been an irksome and time-consuming affair. The commonly employed test of insulin-induced hypoglycaemia (Hollander) is tedious, risky and associated with practical limitations and theoretical objections, which have resulted in its being replaced by the modified sham feed technique in some centres. The postprandial alkaline tide is attributed to HCO3- release consequent to H+ secretion. Any procedure which reduces acid secretion is expected to affect the postprandial urinary pH. This study was performed to evaluate the effect of vagotomy on the postprandial alkaline tide by measuring prevagotomy and postvagotomy fasting and postprandial urinary pH. The results show that postprandial urinary pH falls after vagotomy and this method may be used to assess the completeness of vagotomy. The proposed test is convenient and may be used as a screening method in the assessment of vagotomy and other acid reducing operative procedures, if further validated, by comparison with already established tests.  相似文献   
12.
13.
Development of tolerance to the CNS effects of aminoglutethimide in mice   总被引:1,自引:0,他引:1  
Initially, there is a high incidence of CNS-depressant side-effects when the aromatase inhibitor, aminoglutethimide, is used in the treatment of patients with advanced breast cancer. Tolerance to these effects develops with continued dosing. This study examines the development of tolerance to various indices of CNS depression with the drug in mice. Single doses of aminoglutethimide induced a dose-dependent depression of spontaneous locomotor activity, rotarod performance, righting reflex and body temperature and a dose-related antileptazol activity. On repeated dosing with the drug, tolerance to these various activities occurred. The tolerance was found to be dose-dependent in the rotarod and righting reflex tests and time-dependent in the locomotor and body temperature tests. Although the results do not allow a determination of whether this clearly demonstrated phenomenon in the mouse is primarily functional or dispositional, the slow onset (14 days) for complete tolerance may be indicative of a functional mechanism.  相似文献   
14.
Emergency Room patients at Riverside General Hospital who are found by the attending physician to have depressed sensorium and altered personality are routinely subjected to urine tests for various drugs of abuse including phencyclidine (PCP). The findings of the laboratory analysis of these patients are presented in this paper. The toxicology laboratory of this hospital performs screening procedures for various drugs on urine specimens by thin layer chromatography. Drugs detected are confirmed by gas chromatography and a homogeneous enzyme immunoassay technique. In 1981, 1.6% of the urine specimens of patients in the above-mentioned category were found to be positive for PCP. This percentage increased sharply during 1982 (5.8%) and 1983 (5.6%). During 1984 and 1985 the percentage dropped to 4.2% and 4.6%. It is implied from data that the abuse of this drug in this area has leveled off. The data also indicated that PCP is predominantly used by young adults with ages ranging from 21 to 30 years. The abuse of this drug in people over 40 years of age is comparatively very small. Among users of this drug, 67.5% are men and 32.5% are women. Out of 68 women found to be abusing PCP, 5 delivered their babies in this hospital. PCP was detected in the urine specimens of each of these babies. Four out of the five infants showed withdrawal symptoms such as extreme irritability, jitteriness, hyperactivity with high pitched cries and a poor ability to take food.  相似文献   
15.
de Vries Reilingh  TS  van Geldere  D  Langenhorst  BLAM  de Jong  D  van der Wilt  GJ  van Goor  H  Bleichrodt  RP 《Hernia》2004,8(1):56-59
Polypropylene mesh is widely used for the reconstruction of incisional hernias that cannot be closed primarily. Several techniques have been advocated to implant the mesh. The objective of this study was to evaluate, retrospectively, early and late results of three different techniques, onlay, inlay, and underlay. The records of 53 consecutive patients with a large midline incisional hernia — 25 women and 28 men, mean age 60.4 (range 28–94) — were reviewed. Polypropylene mesh was implanted using the onlay technique in 13 patients, inlay in 23 patients, and underlay in 17 patients. Either the greater omentum or a polyglactin mesh was interponated between the mesh and the viscera. The records of these 53 patients were reviewed with respect to: size and cause of the hernia, pre- and postoperative mortality and morbidity, with special attention to wound complications. Patients were invited to attend the outpatient clinic at least 12 months after implantation of the mesh for physical examination of the abdominal wall. Postoperative complications occurred in 14 (26.4%) patients. The onlay technique had significantly more complications, as compared to both other techniques. Reherniation occurred in 15 (28.3%) patients. The reherniation rate of the inlay technique was significantly higher than after the underlay technique (44% vs 12%, P=0.03) and tended to be higher than the onlay technique (44% vs 23%, P=0.22). Repair of large midline incisional hernias with the use of a polypropylene mesh carries a high risk of complications and has a high reherniation rate. The underlay technique seems to be the better technique.  相似文献   
16.
Sir, I read with great interest the letter by Higgins and co-workers[1].  相似文献   
17.
18.
Intravenous captopril in congestive heart failure   总被引:1,自引:0,他引:1  
Hemodynamic and neurohumoral effects of intravenous captopril were studied in ten patients with severe chronic congestive heart failure (NYHA Functional Class III and IV). Incremental bolus doses of captopril, titrated to a maximum cumulative dose of 15 mg, were given at 10-minute intervals. Systemic arterial pressure, mean pulmonary capillary wedge pressure, systemic vascular resistance, mean pulmonary artery pressure, and heart rate decreased (P less than .05). Cardiac index and stroke volume index increased (P less than .05). Maximum hemodynamic effects occurred after cumulative doses of 7 mg and were seen within 30 minutes after initiation of therapy; responses persisted for 30-90 minutes after the last dose. Plasma renin activity increased, and plasma atrial natriuretic factor concentration decreased. No adverse effects were observed with the use of intravenous captopril. Thus, intravenous captopril produces rapid and favorable hemodynamic improvement in advanced heart failure patients.  相似文献   
19.
J Musarrat  M Ahmad 《Mutagenesis》1991,6(3):207-211
Bacteriophage lambda-Escherichia coli complexes exhibited remarkable sensitivity to alkaline pH 10.0 at 37 degrees C. The decline in plaque forming units after alkali treatment was more pronounced in complexes with some of the radiation repair defective mutants of E. coli K-12, i.e. uvrArecA, recA, rer and lexA mutants as compared to those of uvrA, recB and wild-type strains. The red gene of lambda phage and recA gene of E. coli seem to have a complementary effect on the alkali induced lesions. Alkaline treatment to lysogenic lambda phage was also found to be mutagenic. An enhanced level of mutagenesis was observed when treated phage particles were allowed to adsorb on treated wild-type bacteria. Moreover, the alkali treatment to lysogen (lambda cI857-E. coli) resulted in prophage induction in nutrient broth even at 32 degrees C. Thus on the basis of these results the role of error prone SOS repair systems in the repair of alkali induced lesions in lysogenic bacteriophage lambda has been suggested.  相似文献   
20.
Cross-resistance to anticancer drugs, termed multidrug resistance (MDR), is functionally associated with the expression of a plasma membrane, energy-dependent, drug efflux pump termed P-glycoprotein (PGP), the product of the mdr1 gene. We have shown previously that MCF-7 breast carcinoma cells transfected with the human mdr1 gene (BC-19 cells) exhibit greater MDR when stably transfected with protein kinase C alpha (PKC alpha). We now demonstrate that transfection of BC-19 cells with the gamma isoform of PKC (BC-19/PKC gamma cells), which is not normally present in BC-19 cells, does not confer increased resistance to doxorubicin, despite a 19-fold increase in PKC activity. All of the increased PKC activity is accounted for by PKC gamma and it is rapidly down-regulated by phorbol dibutyrate, within 15 min of treatment. Endogenous PKC alpha and PKC epsilon activities are not affected by phorbol dibutyrate. The cytotoxicity of doxorubicin was similar in BC-19/neo or BC-19/PKC gamma cells after either 2-hr or continuous drug exposure, and co-treatment with phorbol dibutyrate increased resistance to doxorubicin 4-fold in both cell lines. Phosphorylation of PGP was similar in both cell lines and drug accumulation was not affected by overexpression of PKC gamma. These results demonstrate that transfection of PGP-expressing cells with an atypical isoform of PKC does not confer increased MDR, and they suggest that the regulation of PGP is phenotype specific with respect to the isoform of PKC.  相似文献   
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