A Comparison of Quality-of-Life in Patients with Dual Chamber Pacemakers and Individually Programmed Atrioventricular Delays

Dual chamber pacemakers are increasingly implanted to achieve optimal hemodynamics by AV synchrony, but the effect of AV delay programming on the patient's quality-of-life has been less well studied. The influence of an individually programmed AV delay between 100 and 250 ms on quality-of-life was investigated in a randomized, double-blind crossover study of 13 patients (69 ± 10 years of age) with dual chamber pacemakers implanted because of high degree AV block. During radionuclide ventriculography at rest, the "optimal AV delay" with the maximal left ventricular ejection fraction and the "most unfavorable AV delay" with the least ejection fraction were determined. The ejection fraction at rest with the "optimal AV delay" was 51%± 10%, and with the "most unfavorable AV delay," 44%± 11% (P < 0.0001). The optimal AV delay determined by radionuclide ventriculography correlated well with the optimal AV delay determined by Doppler echocardiography using flow velocity integrals (r = 0.78, P < 0.0016). Each patient was assigned in random order to either AV delay during a 2-week period and then the pacing mode was switched for another 2-week period. At the end of each period, patients were assessed by a functional status questionnaire to assess physical capability and two further questionnaires to quantify cardiovascular symptoms or self-perceived health. There were no differences in the two AV delays regarding the patient's perceived physical capability and specific symptoms. The patient's total judgment was identical to the optimal AV delay (score 36%± 19%) and the most unfavorable AV delay (33%± 21%). Thus, in patients with a dual chamber pacemaker, an individually programmed AV delay affects left ventricular function at rest, but has no influence on quality-of-life. The determination of the flow velocity integral by Doppler echocardiography is a simple and reliable method to optimize the AV delay if necessary.     

头孢泊肟酯的合成

头孢泊肟酯是第三代头孢菌素中第一个口服衍生物,具有广谱抗菌活性,对很多革兰氏阴、阳性菌有效,且很少见细菌对本品耐药。文献报道本品的合成方法有多种。笔者以国产氨噻肟头孢为原料经酰化、甲氧基化.酯化和水解4步反应制得。     

Height changes among chronic low back pain patients during intense physical exercise

The possible effects of intense physical exercise on the total body stature of low back pain patients were monitored by circadian total body height measurements. The height was measured with a statiometer, and the change in height was correlated with the changes in the range of motion, pain and subjective disability and degree of disc degeneration seen on magnetic resonance imaging (MRI) pictures. The stature of 24 low back pain patients was measured during a 3-week period. There was an increase of about 3 mm in height after only 4 days of exercise, and by the end of the programme the morning height increased on average by 7.2 mm.
There were also 12 non-rehabilitated low back pain patients but no such increase was noted among them. The gain of height and reduction of pain were found to be statistically signigicantly correlated ( P =0.0001, r =−0.41), as did the gain of height and teh decrease of back disablity (Oswestry index) ( P <0.0001, r =−0.39). Circadian total height measures but not the MR images will change due to the active back rehabilitation programme.     

早期肝硬化的临床特点与诊断

目的：认识早期肝硬化的临床特点并作出诊断。材料与方法：对经病理确诊的早期肝硬化及慢活肝各１３０例临床资料进行对照分析。结果：早期肝硬化与慢活肝在蜘蛛痣、肝掌、慢性肝病面容、Ａ／Ｇ异常、γ＞０．２５及ＨＢＶ感染的家庭聚集等方面存在差异（Ｐ＜０．０２５～０．００ｌ）。结论：掌握早期肝硬化的临床特点，可对其作出正确的诊断。     

西洋参茎叶皂甙对某些免疫功能影响的实验研究

作者从西洋参茎叶中提得总皂甙(panaxquinquefolium sapoin)简称PQS,观察了PQS对免疫功能的影响。结果PQS体内给药8天后100mg/kg组T、B淋巴细胞转化率显著高于对照组(P<0.05);可促进conA诱导IL—2产生(P<0.05);脾脏T细胞百分率及B细胞的抗体产生水平均显著高于对照组(P<0.01),说明在100mg/kg剂量下,机体的T、B淋巴细胞功能都有明显的增强作用。     

Measurement of cerebral vascular extraction fractions in the rat using intracarotid injection techniques

A small volume (5 μl) common carotid arterial injection method is described for the quantitation of cerebral vascular extraction fractions (E_t) of diffusion limited tracer molecules in the rat. The method is a modification of a technique diffusion duced by Oldendorf and widely used for the study of blood-brain barrier phenomena. While the Oldendorf technique has proven valuable for estimating the relative permeabilities of substances, it is limited in measuring E_t under conditions of physiologically or pharmacologically altered permeability or blood flow. The method described in this paper — using a small volume (5 μl) common carotid injection, a freely diffusible reference tracer, [¹⁴C]butanol, and a 5 sec circulation time — allows for measurements of E_t that reflect changes in blood flow and small differences in permeability. The modified method is important for the study of the regulation of cerebral vascular permeability and flow in an inexpensive animal model.     

Geographic differences in HBV related,autoimmune, and cryptogenic chronic active hepatitis

ABSTRACT— To clarify the importance of ethnic and geographic factors in chronic active hepatitis (CAH), HBV markers and autoantibodies (AMA, ANA, SMA), have been compared in 158 patients with biopsy-proven CAH from New York City and in 92 patients with CAH from Milan. HBsAg-positive CAH was more frequently observed in Milan (49%) than in New York City (27%). However, among HBsAg-positive patients, HBcAg, HBeAg, and epidemiologic risk factors for acquisition of HBV infection were more frequently found in New York than in Italy. The prevalence of HBsAg-negative, anti-HBc-positive CAH and cryptogenic CAH was similar in the two cities, while autoimmune CAH was more frequently observed in New York (20%) than in Milan (2%). In particular, the prevalence of autoimmune hepatitis was higher among Jewish patients than among patients of Anglo-Saxon or Latin ethnic background in New York. Thus, environmental and/or ethnic factors may influence the prevalence of the four major types of CAH.     

Ascorbic acid inhibition of Na,K-adenosine triphosphatase of rat forebrain without peroxidation of membrane lipids

Using reagents and membrane preparations from which contamination had been carefully removed, we found that ascorbic acid inhibited rat brain Na,K-ATPase without causing lipid peroxidation, unlike the conventional belief; the inhibition was prevented by catecholamines and EGTA. Ascorbic acid radicals, instead of active oxygen, may play a role in the inhibition.     

Equivalence studies for complex active ingredients and dosage forms

This article examines the United States Pharmacopeia (USP) and its role in assessing the equivalence and inequivalence of biological and biotechnological drug substances and products-a role USP has played since its founding in 1820. A public monograph in the United States Pharmacopeia-National Formulary helps practitioners and other interested parties understand how an article's strength, quality, and purity should be controlled. Such a monograph is a standard to which all manufactured ingredients and products should conform, and it is a starting point for subsequent-entry manufacturers, recognizing that substantial additional one-time characterization studies may be needed to document equivalence. Review of these studies is the province of the regulatory agency, but compendial tests can provide clarity and guidance in the process.