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31.
Effect of converting enzyme inhibitors on tissue converting enzyme and angiotensin II: therapeutic implications 总被引:1,自引:0,他引:1
Local tissue renin-angiotensin systems have recently been discovered in various organs, and evidence is accumulating that inhibition of these local renin-angiotensin systems may contribute to the actions of converting enzyme (CE) inhibitors. Measurements of CE activity and angiotensin II concentrations revealed that after oral administration of CE inhibitors, CE was inhibited not only in lung vascular endothelium and blood, but also in the heart, kidney, vascular wall, brain and other organs. The functional significance of tissue CE inhibition is suggested first by the antihypertensive effect of brain CE inhibition in spontaneously hypertensive rats, second by the concomitant persistence of blood pressure decrease and CE inhibition in vascular wall and kidney after long-term oral CE inhibitor treatment and third by ex vivo experiments demonstrating marked effects of oral CE inhibitor pretreatment on cardiac function in isolated rat hearts. Local inhibition of tissue renin-angiotensin systems may be an important factor involved in the beneficial effects of CE inhibitors in such cardiovascular diseases as arterial hypertension, congestive heart failure and cardiac arrhythmias. 相似文献
32.
33.
M. Ito T. F. Lang M. Jergas M. Ohki M. Takada T. Nakamura K. Hayashi H. K. Genant 《Calcified tissue international》1997,61(2):123-128
This study examined trabecular bone mineral density (BMD) in Japanese women with and without spinal fracture, and compared
the results to American women with and without fracture. The quantitative computed tomography (QCT) systems used at the University
of California, San Francisco (UCSF) and at Nagasaki University were cross-calibrated. Normative BMD was assessed with the
K2HPO4 liquid phantom in 538 Americans aged 20–85 years, and with the B-MAS200 phantom in 577 Japanese aged 20–83 years. These BMD
were adjusted for use with the Image Analysis solid phantom using the result of cross-calibration. The trabecular BMD in 111
postmenopausal American women (55 with fracture), and in 185 postmenopausal Japanese women (67 with fracture) were compared
for investigation of the difference in BMD values relative to fracture status. The absolute BMD values in Japanese were lower
than those in Americans, and the differences were greater with advancing age. The magnitude of the BMD difference was 8.6,
20.5, 38.1 mg/cm3 in women aged 20–24 years, 40–44 years, 60–64 years, respectively. In premenopausal women, BMD began to decrease at the age
of 20 in Japanese, whereas the peak bone mass was maintained until the age of 35 in the American women. In immediate postmenopausal
women, BMD significantly decreased in both populations. In later postmenopausal women, BMD significantly decreased with age
in the Japanese women but decreased less rapidly in the American women. The aging decrease of BMD was 1.4% and 2.2% per year
in the later postmenopausal American and Japanese women, respectively. The fracture threshold is considered to be lower in
Japanese women. However, the BMD difference between American and Japanese women with fracture was similar to that without
fracture. The Z-scores of fracture subjects versus controls were 2.9 in American and 1.8 in Japanese women. In conclusion,
Japanese women were found to have a lower BMD and lower fracture threshold than American women. The significant decrease of
spinal trabecular BMD in late postmenopause is potentially responsible for the higher prevalence of spinal fracture in Japanese
women.
Received: 18 December 1995 / Accepted: 23 September 1996 相似文献
34.
35.
P D Clouston C B Saper T Arbizu I Johnston B Lang J Newsom-Davis J B Posner 《Neurology》1992,42(10):1944-1950
We studied nine patients with a subacute onset of a pancerebellar syndrome. Six had known cancer (three small-cell carcinoma of the lung [SCLC], one metastatic small-cell carcinoma, one small-cell carcinoma of the prostate, and one non-Hodgkin's lymphoma). Six of eight who had neurophysiologic testing, including the three patients without detectable cancer, had coexistent Lambert-Eaton myasthenic syndrome (LEMS). In two of the patients, LEMS was discovered only by neurophysiologic testing. We looked for anti-Purkinje cell autoantibodies in all patient's sera and in four patients' CSF. We also looked for autoantibodies to voltage-gated calcium channels (VGCCs) in seven patients' sera and two patients' CSF, using the 125I-omega-conotoxin radioimmunoassay. We were unable to detect anti-Purkinje cell autoantibodies in any patients' serum or CSF. However, there were raised titers of anti-VGCC autoantibodies in five of seven patients' serum, including one patient with SCLC who did not have LEMS, and in the CSF of one of two patients. We conclude that the frequency of presentation of a pancerebellar syndrome with LEMS is higher than expected by chance and is usually associated with cancer. In some of these patients, LEMS may be clinically occult. The presence of LEMS and raised titers of anti-VGCC autoantibodies in some patients with subacute cerebellar degeneration is suggestive of an autoimmune etiology even though anti-Purkinje cell antibodies could not be detected. Anti-VGCC autoantibodies are not confined to LEMS. They may be found at high titer in CSF as well as serum. 相似文献
36.
Zusammenfassung. Die Auswirkungen einer Immunsuppression auf perioperative pathophysiologische Vorg?nge stellen besondere Anforderungen sowohl
in bezug auf die Indikationsstellung zu einem operativen Eingriff als auch an das perioperative Management. Eine immunsuppressive
Therapie kann ein ver?ndertes oder v?llig fehlendes Abwehrverhalten bei entzündlichen Prozessen bewirken, so da? die hierfür
typischen klinischen Anzeichen nur schwach oder gar nicht ausgepr?gt werden. Dies kann zu einer gef?hrlichen Latenz in der
Diagnostik akut lebensbedrohlicher Erkrankungen bei immunsupprimierten Patienten führen. Darüber hinaus tragen die ver?nderte
Reaktivit?t des Patienten auf Stre?, eine verz?gerte und verminderte Wundheilung sowie insbesondere die erh?hte Infektanf?lligkeit
zu einem gesteigerten Operationsrisiko bei. Perioperativ sind daher eine konsequente klinische überwachung des Patienten und
ein lückenloses Monitoring der Immunsuppression unverzichtbar. Für den klinischen Umgang mit immunsupprimierten Patienten
ergeben sich hieraus 2 unterschiedliche Pr?missen hinsichtlich der Indikationsstellung bei Elektiv- und Notfalleingriffen.
W?hrend unter Elektivbedingungen eine sorgf?ltige Operationsplanung unter besonderer Berücksichtigung der m?glichen Risiken
für Patient und Transplantat unabdingbar ist, so lassen die oftmals gro?en diagnostischen Unsicherheiten bei entzündlichen
Vorg?ngen sowie die erheblichen Risiken eines verz?gerten Therapiebeginns eine eher etwas gro?zügigere Indikationsstellung
zur operativen Intervention in Zweifelsf?llen berechtigt erscheinen. Operativ technisch ist generell auf ein gewebeschonendes
und atraumatisches Vorgehen zu achten, weiterhin sollte eine besondere Sorgfalt bei Anastomosenn?hten und Wundverschlu? bestehen.
Darüber hinaus sind von Seiten des Chirurgen die Einflu?m?glichkeiten auf den postoperativen Verlauf begrenzt.
相似文献
37.
38.
D. P. Southall M.D. M.R.C.P. V. A. Stebbens B.Sc. Research Assistant R. Mirza B.Sc. Research Assistant M. H. Lang B.Sc. Research Assistant C. B. Croft M.B. Ch.B. F.R.C.S E. A. Shinebourne M.D. F.R.C.P 《Developmental medicine and child neurology》1987,29(6):734-742
Six of 12 children with Down syndrome (DS) tested by means of long-term tape-recordings of oxygen saturation, breathing movements and expired CO2 were found to have previously undetected and severe upper airway obstruction during sleep. In five cases the obstruction occurred in the pharynx and in the sixth it was due to bilateral choanal stenosis. When compared with age-matched controls, overnight tape-recordings showed episodes of abnormal arterial hypoxaemia and an abnormally elevated end-tidal CO2. Episodes of obstruction were most marked during sleep associated with a non-regular breathing pattern. Abnormal episodes of hypoxaemia were associated with continued breathing movements. Sometimes there was no airflow (complete obstruction); at other times airflow continued normally or was reduced in amplitude (partial obstruction). During episodes of partial or complete airway obstruction the inspiratory waveform showed a characteristic shape. These results show sleep-related upper airway obstruction to be an often undetected complication of DS and all necessary measures should be taken to overcome the obstruction when it reaches the stage of producing abnormal hypoxaemia. Choanal dilatation and tracheostomy were successful in treating two of the children. Tonsillectomy and adenoidectomy were successful for one child, but only of marginal benefit for two others. 相似文献
39.
Antonietta C. Rouget MD Reuben A. Lang PhD Michel R. Joffres MD 《Sexual abuse : a journal of research and treatment》1988,1(1):95-114
The prevalence of abnormal physical signs (e.g., bleeding, scars, or bruises) and genital infections, notably Chlamydia Trachomatis, Neisseria Gonorrhea, and Herpes Simplex Genitalis was studied in 219 female children with validated sexual abuse. They were compared to 113 nonabused female children. The average abused child was 8.3 years old, with 69% having been abused on multiple occasions. Most offenders were family members (65%) or a close family friend (22%). Stranger-perpetrated sexual assault, in the sample, was low (9.1%). Few children had severe vaginal tears, though 56% showed signs of subtle anatomical injury to their genitalia. No similar anatomical abnormalities were present in nonabused children. Among the sexually abused children and adolescents, 35% were colonized with a pathogen or a potential pathogen, compared to a prevalence rate of 18.5% in non-abused children. The proportion of abused children colonized with Ureaplasma Urealyticum and Mycoplasma Hominis was not significantly different from that found in nonabused children. At present, Neisseria gonorrhea and Chlamydia Trachomatis remain the only conclusive markers for sexual abuse. It is recommended that routine cultures of the pharyngeal, rectal, and vaginal areas be taken in all cases of suspected child sexual abuse, regardless of clinical findings. 相似文献
40.
E Lang 《Zeitschrift für Gerontologie》1988,21(6):352-358
The potential of rehabilitation for geriatric patients depends on physiological considerations about the aging organism, as well as diseases, accompanied by the natural aging process. A common feature of the aging process of human organs is a general loss of adaptability that contributes to hypocirculation. The potential for rehabilitation may be considerably limited by diseases which burden the circulatory system (atherosclerosis, coronary heart disease, hypertension, and hypotension). Cardiac arrhythmias occurring during rehabilitation procedures call for special care. Mode and intensity of the rehabilitation program will be determined by cardiac and circulatory reactions following active rehabilitation procedures. Isometric exercise stress in conjunction with pressure breathing leads to an excessive rise of blood pressure in systemic and pulmonary circulation. Therefore dynamic muscle actions should be preferred as the most reasonable active training, but there is the possibility of heart-circulation problems arising, depending on the intensity of training. 相似文献