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1.
The aim of the study was to evaluate the importance of atrial synchronism for pacing therapy of patients with mixed carotid sinus syndrome. On 23 patients (21 m, 2 f; mean age 69 +/- 8 years) affected by symptomatic mixed carotid sinus syndrome we performed: 1) the study of ventriculo-atrial conduction, 2) the evaluation of pacemaker effect and 3) the carotid sinus massage in standing position during VVI and DVI temporary pacing. All patients received a permanent DVI pacemaker and then underwent a two-month period single-blind, randomized, cross-over study on DVI vs VVI mode. During DVI period, no syncope occurred in any patients, minor symptoms persisted in 11 (48%) of them; during VVI period syncopes recurred in 3 patients, symptoms requiring the withdrawal of VVI pacing and premature DVI reprogramming in 8, minor symptoms were observed in 17 (74%). A comparison between 14 patients who preferred DVI period (Group A) and the remaining 9 patients who had no preference for DVI and VVI period (Group B) revealed that Group A patients had a greater pacemaker effect (-34 +/- 16 mmHg vs -16 +/- 14 mmHg; p less than 0.02) and a higher prevalence of ventriculo-atrial conduction (78% vs 44%; p = 0.1), while the entity of the systolic pressure fall caused by carotid sinus massage was similar in the two groups both during VVI mode (Group A -51 +/- 16 mmHg vs Group B -56 +/- 27 mmHg) and DVI mode (Group A -38 +/- 17 mmHg vs Group B -45 +/- 17 mmHg).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
Forty consecutive adult patients under the age of 50 with acute non-lymphoblastic leukemia (ANLL) in first complete remission, underwent autologous bone marrow transplantation (ABMT) between March 1984 and April 1990. The conditioning regimen employed included cyclophosphamide and total body irradiation, followed by the administration of unpurged ABMT. The median time from diagnosis to transplant was 7 months (3-15 months), and the median time from complete remission to ABMT was 4 months (range 3-9 months). Twenty-two (51%) patients remain in complete remission 6-81 months (median 24 months) after ABMT.

The causes of death were, recurrent leukemia (11 patients), parenchymal toxicities such as acute respiratory distress syndrome and veno-occlusive disease (3 patients), hemorrhage (2 patients) and infection (2 patients). Eleven patients relapsed after 3-12 months (median 5 months). This study has produced survival data comparable to those of other institutions employing TBI for either allo or autotransplants.  相似文献   
3.
The expanded Hansen method was tested for determination of the solubility parameters of two non-steroidal anti-inflammatory drugs, naproxen and sodium diclofenac. This work describes for the first time the application of the method to the sodium salt of a drug. The original dependent variable of the expanded Hansen method, involving the activity coefficient of the drug, was compared with the direct use of the logarithm of the mole fraction solubility lnX2 in the solubility models. The solubility of both drugs was measured in pure solvents of several chemical classes and the activity coefficient was obtained from the molar heat and the temperature of fusion. Differential scanning calorimetry was performed on the original powder and on the solid phase after equilibration with the pure solvents, enabling detection of possible changes of the thermal properties of the solid phase that might change the value of the activity coefficient. The molar heat and temperature of fusion of sodium diclofenac could not be determined because this drug decomposed near the fusion temperature. The best results for both drugs were obtained with the dependent variable lnX2 in association with the four-parameter model which includes the acidic and basic partial-solubility parameters δa and δb instead of the Hansen hydrogen bonding parameter δh. Because the dispersion parameter does not vary greatly from one drug to another, the variation of solubility among solvents is largely a result of the dipolar and hydrogen-bonding parameters, a fact that is being consistently found for other drugs of small molecular weight. These results support earlier findings with citric acid and paracetamol that the expanded Hansen approach is suitable for determining partial-solubility parameters. The modification introduced in the expanded Hansen method, i.e. the use of lnX2 as the dependent variable, provides better results than the activity coefficient used in the original method. This is advantageous for drugs such as sodium diclofenac for which the ideal solubility cannot be estimated. This paper shows for the first time that the method is suitable for determination of the partial-solubility parameters of a sodium salt of a drug, sodium diclofenac.  相似文献   
4.
A hospital-based case-control study of renal cell cancer was conducted in northern Italy betwen 1986 and 1989, with 240 cases of renal cell cancer (150 males and 90 females), and 665 controls (445 males and 220 females) chosen on the basis of age, sex, and area of residence. No associations were found between renal cell cancer and: body mass index (BMI); number of cigarettes smoked; age at starting to smoke; years of smoking; consumption of wine, beer, spirits, coffee, decaffeinated coffee; tea; intake of animal protein, fruits, and vegetables; various resproductive factors; hormonal use; sexual habits; sexually transmitted diseases; or selected occupational exposures. The odds ratio (OR) was above unity in smokers (OR=1.34 for 15 cigarettes/day), but the trends in risk with dose or duration were not statistically significant. Significant positive associations were found between renal cell cancer and sources of fat intake, especially margarine (OR for highest vs lowest intake = 1.71), and oils (OR=1.89) whereas carrot intake showed a negative association (OR=0.62). Also, a history of nephrolithiasis and multiple episodes of cystitis showed weak positive associations (OR=2.00, 95 percent confidence interval (CI) 1.07–3.73; and OR=1.60, 95 percent CI 0.95–2.70, respectively).Address reprint requests to Dr Talamini. The work was conducted with the contribution of the Italian Association for Cancer Research, Milan, Italy and the CNR (Italian National Research Council) Applied Projects Oncology (Contract n. 85.02209.44).Drs Talamini, Barón, Barra, Bidoli, Serraino, and Franceschi are in the Epidemiology Unit, Aviano Cancer Center, Via Pedemontana Occ. 33081 Aviano (PN) Italy. At the time of this work, Dr Barón was a visiting biostatistician from the Department of Preventive Medicine and Biometrics, University of Colorado, Health Science Center, CO, funded by the National Cancer Institute (US) and the Italian National Research Council. Dr Franceschi is also chief of the Hormones and Sexual Factors and Cancer Working Group of the European Organization for Cooperation in Cancer Prevention Studies, Bruxelles, Belgium. Drs La Vecchia and Negri are in the Mario Negri Institute for Pharmacological Research, Milan, Italy. Dr La Vecchia is also in the Institute of Social and preventive Medicine, University of Lausanne, Switzerland.  相似文献   
5.
The depicted procedure minimizes the hazards of aggressive manipulations, and excludes any possibility of so-called "warm ischaemia". The kidneys are flushed out in situ with cool pulsatile perfusion through an aortic cannula. Kidneys, aorta and inferior vena cava are then removed en-bloc without interrupting the perfusion, and preserved in Collins' solution at 4 degrees C. After a 6 to 19 hour storage time, one of the kidneys is transplanted on another dog, while the second one is submitted to histological examination. Nine transplantations were carried out, followed in 7 cases with a most satisfactory diuresis resuming, and with urinary ionic levels, as well as daily urea output, normalization within 48 hours. Histologic examination showed an unaffected glomerular apparatus, but some mild tubular lesions.  相似文献   
6.
BACKGROUND: Surgical coronary artery reconstruction for diffuse coronary disease is described and assessed. METHODS: A long arteriotomy, internal thoracic artery graft, and exclusion of atheromatous plaques from the coronary lumen are the bases of the technique. One hundred eighteen reconstructions were performed in 108 patients with a mean age of 59 years. Stable angina was present in 62% of patients and unstable angina in 22%. Sixteen percent had had a recent myocardial infarction. The reconstructions involved 94 left anterior descending coronary arteries, 17 marginal, 5 diagonal, and 2 right coronary arteries. RESULTS: The perioperative mortality rate was 3.7% (4 patients). The rate of perioperative myocardial infarction was 6.3%. Mean follow-up was 29 months (standard deviation, 10 months). Two patients were lost to follow-up. Ninety patients were free from angina and cardiac-related events. Five patients sustained a myocardial infarction, 3 were in congestive heart failure, 3 had class II angina, and 1 died of stroke. Seventy-four of the surgical coronary artery reconstructions have been angiographically evaluated (29 months): 94.6% of the internal thoracic artery grafts were completely patent, and 70 of the reconstructions were patent without restenosis. String signs and occlusions were present in two internal thoracic arteries each. CONCLUSIONS: This technique allows revascularization of severely and diffusely diseased coronary arteries with encouraging results.  相似文献   
7.
8.
Hypertension complicates 6-8% of pregnancies and includes the following four conditions: hypertension preceding pregnancy or documented before the 20th week of gestation; pre-eclampsia (PE) / eclampsia; chronic hypertension with superimposed pre-eclampsia; and gestational hypertension. The latter is defined as a significant rise in blood pressure after the 20th week of pregnancy in previously normotensive women, to over 140/90 mmHg. When blood pressure remains above 160/110 mmHg, it is considered severe. PE is defined as the presence of proteinuria (≥300 mg/24 h) in pregnant women with hypertension. The hypertensive syndromes of pregnancy are among the leading causes of maternal and fetal morbidity and mortality and anti-hypertensive treatment is part of the therapeutic arsenal used to prevent serious complications. Although the role of utero-placental insufficiency due to deficient migration of trophoblasts to the spiral arteries is universally accepted, the pathophysiology of PE remains largely unknown and is the subject of debate. No effective ways of predicting or preventing PE have been found, which highlights the need for further research in this field. This review aims primarily to evaluate recent advances in our understanding of the pathophysiology of gestational hypertension and especially PE, and new ways of predicting PE. Additionally, we present a brief review on the diagnosis, prevention and treatment of PE.  相似文献   
9.
10.
SUMMARY. This study aims to evaluate by the use of 24‐hour combined multichannel intraluminal impedance and pH monitoring (MII‐pH) the efficacy of the Nissen fundoplication in controlling both acid and nonacid gastroesophageal reflux (GER) in patients that underwent Heller myotomy for achalasia. It has been demonstrated that fundoplication prevents the pathologic acid GER after Heller myotomy, but no objective data exists on the efficacy of this antireflux surgery in controlling all types of reflux events. The study population consisted of 20 patients that underwent laparoscopic Heller myotomy and Nissen fundoplication for achalasia. All patients were investigated with manometry and MII‐pH. MII‐pH showed no evidence of postoperative pathologic GER. The overall number of GER episodes was normal in both the upright and recumbent position. This reduction was obtained because of the postoperative control of both the acid and nonacid reflux episodes. The Nissen fundoplication adequately controls both acid and nonacid GER after extended Heller myotomy. Further controls with MII‐pH are warranted to check at a longer follow‐up for the efficacy of this antireflux procedure in achalasic patients.  相似文献   
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