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91.
The aim of this study was to create and measure the predictive validity of a screening instrument that identifies older people who are at risk for developing a need for long-term care within a year. This was an observational study, with participants allocated to either a derivation cohort or a validation cohort, in the United States. A nationally representative sample of older community-dwelling Medicare beneficiaries (n = 6,538) participated in the Medicare Current Beneficiary Survey. Questions addressed sociodemographic, functional, health-related, and utilization characteristics in 1991 and 1992, linked to records of Medicare payments for health services during 1991-1992. In the derivation cohort, 14 self-reported characteristics were significant predictors of developing a need for long-term care within 1 year. In the validation cohort, these 14 characteristics identified a high-risk subgroup (18%) that, during the following year, developed a need for long-term care at six times the rate of the low-risk majority. This brief survey instrument identifies a high-risk minority of older people that will, during the following year, develop a need for long-term care at six times the rate of the low-risk majority. This instrument may be useful for targeting at-risk subgroups of older populations to receive interventions designed to preserve functional independence and avert the need for long-term care.  相似文献   
92.
Disseminated tuberculosis usually occurs in immunocompromised hosts. Involvement of bone marrow, liver, and spleen is infrequent. A previously healthy 15-year-old boy presented with body weight loss, prolonged fever, neck lymphadenopathy, pancytopenia, and hepatosplenic microabscesses within the recent month and was transferred to our hospital. Bone marrow studies showed hypocellular marrow. Based on his clinical manifestations, hemophagocytic syndrome was initially suspected. Pancytopenia resolved after administration of intravenous immunoglobulin but caseous necrosis and/or positive acid-fast stain were subsequently demonstrated in the lymph node biopsy and sputum. Cultures from these 2 specimens grew Mycobacterium tuberculosis. Fever continued in a low-grade pattern even under antituberculous therapy with rifampin, isoniazid, pyrazinamide and ethambutol. Five months after admission, fever subsided after splenectomy and liver wedge resection. Microscopic examinations of both the liver and spleen showed mycobacteria-related granulomatous inflammation and caseating necrosis. This report suggests that tuberculosis infection should be considered in the differential diagnosis in patients with prolonged fever, pancytopenia and hepatosplenic abscesses.  相似文献   
93.
BACKGROUND/PURPOSE: This study was designed to investigate the effects of 6 months of nocturnal nasal positive pressure ventilation (NNPPV) on respiratory muscle function and exercise capacity in patients with chronic respiratory failure. METHODS: A prospective, randomized, controlled design was used. Twenty-nine patients with chronic respiratory failure were enrolled and allocated to either the NNPPV (n = 14) or control group (n = 15). Patients in the NNPPV group received bi-level positive pressure ventilation via nasal mask for 6 consecutive months. Arterial blood gas, respiratory muscle assessment and 6-minute walk test (6MWT) were performed before and after the 6-month NNPPV intervention. Respiratory muscle function was assessed using the variables of maximal inspiratory pressure (Pimax), maximal expiratory pressure (Pemax), and maximum voluntary ventilation (MVV). RESULTS: Subjects in the NNPPV group showed a significant improvement in blood gas exchange and increased 6-minute walk distance (6MWD) compared to baseline and the control group. The 6MWD was significantly increased from 257.1 +/- 114.1 to 345.2 +/- 109.9 m (34.3%) in the NNPPV group. NNPPV also significantly improved MVV and Pimax relative to baseline. MVV was significantly increased from 19.2 +/- 6.5 to 22.3 +/- 7.1 L/min (16.1%) in the NNPPV group (p < 0.05). Furthermore, there was a significant correlation between the magnitude of MVV improvement and 6MWD change. CONCLUSION: The 6-month NNPPV treatment significantly decreased the partial pressure of carbon dioxide and improved daytime respiratory muscle function, thus contributing to exercise-capacity increase in patients with chronic respiratory failure.  相似文献   
94.
分娩期连续电子胎心监护用于胎儿评估   总被引:1,自引:0,他引:1  
1背景 在美国,每4例孕妇中有3例在产群中及分娩时使用电子胎儿监护(EFM)(NCHS1993)。1989年,美国妇产科学院(ACOG1989)发表了一项声明,对于低危妊娠既可使用EFM,也可使用间断性胎心听诊;但是,美国预防保健委员会(USPSTF1989)和加拿大的定期健康检查委员会(CTFPHE1994)对高危妊娠仍保留使用EFM。尽管有人对EFM的效果和安全性表示担忧(Thacker 1987:Thacker 1995),  相似文献   
95.
BACKGROUND: High tibial osteotomy (HTO) is a well-established treatment for unicompartmental gonarthrosis of the knee, but its durability and complications remain controversial. We previously introduced a novel dome-shaped HTO, and the long-term follow-up results using this technique are analyzed in this study. METHODS: We treated 25 varus knees in 22 patients with medial gonarthrosis, using a specially designed calibrated cutting jig along with rigid external fixation and early joint motion postoperatively. A total of 16 patients (19 knees) completed the study protocol and were followed up for 13-16 years (mean, 15 years). RESULTS: The surgery attempted to obtain 8 degrees valgus; the actual postoperative alignment averaged 12.4 degrees valgus, which decreased significantly to 7.8 degrees valgus after 5 years. The outcome as assessed by the Hospital for Special Surgery knee score was excellent or good in 18 knees at 5 years postoperatively, and in 13 knees at the final follow-up, showing a significant deterioration with time. Loss of correction with time was not correlated with the postoperative alignment achieved: at 5 years, loss greater than 2 degrees was found in 12 knees, but their mean corrected angle (11.8 degrees valgus) was not significantly different from that of the others (13.3 degrees valgus). Nor was the loss of correction correlated with the knee scores. The mean amount of joint motion after surgery did not change significantly with time: 124 degrees preoperatively and 114 degrees at the final follow-up. The patellar position also did not change from preoperative values during postoperative follow-up: mean Insall-Salvati index was 0.88 before and 0.90 5 years after surgery, neither showing patella baja. CONCLUSION: Dome-shaped HTO is a durable time-buying procedure for patients with unicompartmental medial gonarthrosis, and can avoid subsequent development of patella baja that may complicate further prosthetic arthroplasty.  相似文献   
96.
Bi-directional interactions between visual areas in the awake behaving cat   总被引:1,自引:0,他引:1  
The study of the cooperativity among cortical areas is essential to our understanding of brain functioning. Here we investigated the relative contributions of top-down and bottom-up directed interactions between area 17 and area 7 of the cat visual system. Bipolar local field potentials were recorded while the animals performed a go/no-go task or were in a quiet resting state. The data were analyzed by applying measures of interaction based on the Wiener-Granger causality concept. We found that during the visual task top-down directed interactions were of a similar magnitude as the bottom-up component. Second, interareal couplings tended to increase in conditions requiring a discriminative effort. Third, during behaviors not dominated by visual processing non-directed interactions increased.  相似文献   
97.
Chemoreflexes: an experimental study   总被引:5,自引:0,他引:5  
HYPOTHESIS: Transmyocardial laser revascularization (TMLR) will not denervate the heart, because it does not destroy all of the afferents. This study was designed to determine if stimulation of cardiac sympathetic and vagal afferents from an area of the left ventricle treated with TMLR could evoke reflex effects, and thus whether TMLR would denervate the heart. METHODS: The effect of TMLR on reflexes evoked by chemically stimulating cardiac afferents was examined in 9 dogs. Bradykinin and capsaicin were applied topically or injected into the left anterior descending coronary artery before and after TMLR and after bilateral vagotomy and sympathectomy. Aortic (AoP) and left ventricular pressures (LVP) and electrocardiography were monitored. The first derivatives of LVP (dP/dt) were calculated. RESULTS: Topical bradykinin elicited variable hemodynamic responses. Topical capsaicin evoked pressor responses, increasing mean (+/- SEM) AoP (105+/-9 to 115+/-9 mm Hg; P<.001) and positive dP/dt (+dP/dt) (1032+/-81 to 1159+/-10 mm Hg/s; P<.01) before TMLR. Intracoronary capsaicin evoked a depressor response before TMLR. Pressor responses remained intact after TMLR with increases in mean AoP and +dP/dt (115+/-6 to 128+/-5 mm Hg and 1039+/-98 to 1136+/-100 mm Hg/s, respectively; P<.01). Depressor responses also remained intact after TMLR (91+/-10 vs 101+/-11 mm Hg [P<.02], and 865+/-104 vs 931+/-104 mm Hg/s [P<.05], respectively). Hemodynamic responses were diminished after bilateral vagotomy and abolished after bilateral sympathectomy. CONCLUSION: Since activation of cardiac afferent nerves and reflex responses remained intact after TMLR, but changed after vagotomy or sympathectomy, TMLR does not denervate the heart sufficiently to be the cause of improved angina after TMLR.  相似文献   
98.
Osteosarcoma is a very malignant bone tumor which has a high metastatic potential and usually lead to poor prognosis. The adhesion of tumor cells to the endothelium or extracellular matrix (ECM) is an essential step in the metastatic cascade. We investigated the effect of thrombin on the adhesion activity of the osteosarcoma cell line, ROS 17/2.8. Incubation with the low concentrations of thrombin (0.01-5 U/ml, 5 min to 24 h) elevated the adhesion activity of ROS 17/2.8 to both human umbilical vein endothelial cells (HUVEC) and extracellular matrix, with the peak effect at the concentration of 0.5 U/ml for 30 min at 37 degrees C. The ROS 17/2.8 cells responded to thrombin by a peak effect of increased adhesion to HUVEC (5.5 folds vs. control) and fibronectin (4.8 folds) after thrombin pretreatment (0.5 U/ml, 30 min, 37 degrees C). Pretreatment with monoclonal antibodies against beta3 integrins, including anti-alphavbeta3, 10E5 and 7E3, effectively antagonized the thrombin-enhanced cell adhesion activity, whereas anti-alpha3beta1 and anti-alpha5beta1 did not antagonize the enhanced cell adhesion. Rhodostomin, an Arg-Gly-Asp (RGD)-containing snake venom peptide, and synthetic peptide RGDS also blocked the thrombin-enhanced ROS 17/2.8 cell adhesion. This study demonstrated that thrombin enhanced the cell adhesion of ROS 17/2.8 cells to HUVEC or ECM through an upregulation of beta3 integrins, and rhodostomin was a strong inhibitor on thrombin-enhanced cell adhesion, either to HUVEC or fibronectin substratum.  相似文献   
99.
The clinical manifestations of chronic disseminated histoplasmosis are non-specific and resemble those of other chronic infections and malignancies. We report the radiographic, sonographic and contrast-enhanced CT appearances of histoplasmosis in an adult male with non-insulin dependent diabetes mellitus, who was HIV negative and presented with weight loss and pyrexia. Imaging studies simulated tuberculosis with mediastinal lymphadenopathy, bilateral fibrotic lung lesions, hepatomegaly and bilateral hypoattenuating adrenal enlargement, without clinical or laboratory evidence of hypoadrenalism. Computed tomography-guided fine-needle aspiration biopsy of adrenal glands revealed Histoplasma capsulatum. We report our experience to increase awareness of the imaging spectrum of disseminated histoplasmosis and its similarity to tuberculosis as, with increasing incidence of AIDS, the chances of these infections are likely to increase. Moreover, awareness of this entity is important because it is known that untreated disseminated histoplasmosis is fatal.  相似文献   
100.
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