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101.
Spinal Trabecular Bone Loss and Fracture in American and Japanese Women   总被引:7,自引:0,他引:7  
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   
102.
This study describes mortality rates and predictors of mortality among late-middle-aged and older (55+) substance abuse inpatients ( n = 21, 139) in Department of Veterans Affairs (VA) Medical Centers in the 4 years after an index episode of care. A total of 24% of the patients died; this mortality rate was 2.64 times higher than expected. Predictors of earlier mortality included older age and nonmarried status, alcohol psychosis and organic brain disorder diagnoses, and several medical diagnoses, including neoplasms, liver cirrhosis, respiratory, endocrine and metabolic, and blood system disorders. Three proxy indicators of illness severity also predicted mortality: more prior inpatient and outpatient medical care and an index episode in an extended care unit. In contrast, more prior outpatient mental health care and remitted status predicted lower mortality. These diagnostic and treatment indicators can be used to identify patients at heightened risk for premature mortality. Moreover, they show that intensive mental health aftercare and remission of substance abuse may delay mortality, even among older patients who have longstanding substance abuse problems.  相似文献   
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Abstract The inflammatory response of immune cells to target cells and cell-matrix molecules is regulated by several receptor-ligand molecules. As fibrosis develops in ongoing chronic rejection after liver transplantation, it is of interest to analyze patterns of integrin receptors and cell-matrix molecules in order to study the relation between immune cells and the stromal and parenchymal cells. In the present study, we demonstrated the expression of these molecules in chronic rejected human liver grafts using immunohistochemical techniques. The results showed a differential expression and induction of integrin receptors and cell-matrix molecules on resident liver cells, especially on sinusoids, reflecting a state of chronic inflammation and a specific interaction between integrin receptors and cell-matrix molecules. The patterns of induced integrin receptors on graft-infiltrating cells was closely related to the local production of cell-matrix molecules and reflected the final sequence of a stepwise progress of the inflammatory reaction.  相似文献   
105.
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   
106.
107.
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   
108.
109.
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   
110.
Human immunodeficiency virus (HIV) is now considered as the causative agent of acquired immunodeficiency syndrome (AIDS). A high risk of AIDS has been reported among patients with hemophilia who received lyophilized commercial factor VIII and IX concentrates of American origin. At a prevalent survey from September to December 1985, HIV antibodies were found in all four patients with hemophilia treated with the batch number W87307, 955 I.U. of American commercial factor VIII concentrate supplied by Armour Pharmaceutical Company, USA. One of the sero-positive patients developed AIDS-related complex (ARC) and died of cerebral hemorrhage. The other three sero-positive patients had abnormalities in cell-mediated immunity. Of them two developed left lumbosacral radiculopathy and hemorrhagic herpes zoster and one remained well so far.  相似文献   
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