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71.
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
72.
Disseminated tuberculosis presenting as multiple hepatosplenic microabscesses and pancytopenia in a teenage boy. 总被引:1,自引:0,他引:1
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
73.
Ling-Ling Chiang Chih-Teng Yu Chien-Ying Liu Yu-Lun Lo Han-Pin Kuo Horng-Chyuan Lin 《台湾医志》2006,105(6):459-467
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
74.
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
75.
Zhang JD Cao YB Xu Z Sun HH An MM Yan L Chen HS Gao PH Wang Y Jia XM Jiang YY 《第二军医大学学报》2006,27(6):664-664
Antifungal activity of natural products is being studied widely. Saponins are known to be antifungal and antibacterial. We have isolated eight steroid saponins from Tribulus terrestris L. , namely TTS-8, TTS-9, TTS-10, TTS-11, TTS-12, TTS-13, TTS-14 and TTS-15. TTS-12 and TTS-15 were identified as tigogenin-3-O-β-D-xylopyranosyl(1→ 2)-[-β-D-xylopyranosyl( 1 → 3 ) 3-β- D-glucopyranosyl ( 1 → 4 )- 1- α-L-rhamnopyranosyl ( 1 → 2 ) 3-β-D-galactopyranoside and tigogenin-3-O-β-D-glucopyranpyranosyl(1→2)-[-β-D-xylopyranosyl(1→ 3)3-β-D-glucopyranosyl(1→4)-β-D-galactopyranoside, respectively. The in vitro antifungal activities of the eight saponins against six fluconazole-resistant yeasts, Candida albicans, Candida glabrata, Candida para psilosis , Candida tropicalis , Candida krusei , and Cryptococcus neo f ormans were studied using microbroth dilution assay. The results showed that TTS-12 and TTS-15 were very effective against several pathogenic candidal species and C. neoformans in vitro. It is noteworthy that TTS-12 and TTS-15 were very active against fluconazole-resistant C. albicans (MIC80 = 4.4, 9.4 mg/ml), C. neoformans (MIC80 =10.7, 18.7 mg/ml) and inherently resistant C. krusei (MIC80 =8.8, 18.4 mg/ml). So in vivo activity of TTS-12 in a vaginal infection model with fluconazole-resistant C. albicans was studied in particular. Our studies revealed TTS-12 also showed in vivo activities against fluconazole-resistant yeasts. In conclusion, steroid saponins TTS-12 and TTS-15 from Tribulus terrestris L. have significant in vitro antifungal activity against fluconazole-resistant fungi, especially TTS-12 also showed in vivo activity against fluconazole-resistant C. albicans. 相似文献
76.
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
77.
Chemoreflexes: an experimental study 总被引:5,自引:0,他引:5
Chiang BB Roberts AM Kashem AM Santamore WP Chien S Gray L Dowling R 《Archives of surgery (Chicago, Ill. : 1960)》2000,135(5):577-581
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
78.
Rong-Sen Yang Huei-Shien Chiang Chih-Hsin Tang Chia-Shin Yeh Tur-Fu Huang 《Toxicon》2005,46(4):387-393
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
79.
Kuo-Chung Lan Hsin-Ju Chiang Tiao-Lai Huang Yu-Jie Chiou Te-Yao Hsu Yu-Che Ou Yao-Hsu Yang 《Journal of assisted reproduction and genetics》2021,38(1):85
PurposeTo study the association between paternal age and schizophrenia in offspring.MethodsThis report describes a nationwide population-based cohort study from 1997 to 2013. Data from Taiwan’s National Health Insurance Research Database were utilized to answer the research question. A total of 17,649 offspring with schizophrenia were selected from 11 million offspring in the general population. Additionally, we established the offspring without schizophrenia as the comparison group by matching the study cohort by age, gender in a 1:4 ratio (n = 70,596).ResultsThe median age at first presentation with schizophrenia was 20 years (interquartile range (IQR), 17 to 24). Comparison of the schizophrenia and non-schizophrenia groups indicated that father’s age at birth (30.0 (IQR), 27 to 33 vs. 29.0 (IQR), 26 to 32 years), mother’s age at birth (26.0 (IQR), 24 to 29 vs. 26.0 (IQR), 23 to 29 years), paternal schizophrenia (2.6% vs. 0.6%), and maternal schizophrenia (4.4% vs. 0.7%) were all significantly greater in the schizophrenia group. In addition, each 5-year increase in father’s age increased the odds of being diagnosed with schizophrenia (model 1: aOR = 1.22; 95% CI 1.20, 1.24; model 2: aOR = 1.20; 95% CI 1.18, 1.23). Subgroup analysis showed that each 5-year increase in father’s age increased the odds of being diagnosed with schizophrenia in male and female offspring, as well as in offspring of mothers and fathers with or without schizophrenia (aOR = 1.20 to 2.20, all p values < 0.01).ConclusionThis study indicated that advanced paternal age increased the risk of schizophrenia in offspring. Offspring born to fathers older by 5-year increments were at heightened risk of schizophrenia. 相似文献
80.
1. The effects of 11 calcium antagonists on (Na+ + K+)-ATPase, Mg2+-ATPase and Ca2+-ATPase activities of rat cortical synaptosomes were studied. 2. All the calcium antagonists studied had inhibitory effects on ouabain-sensitive (Na+ + K+)-ATPase, Mg2+-ATPase and Ca2+-ATPase activities in synaptosomes at high concentrations (10 or 100 microM). 3. Calcium antagonists such as trifluoperazine, flunarizine and cinnarizine had inhibitory effects on Ca2+-ATPase activity at low concentrations (1-10 microM). 4. Trifluoperazine and La3+ had inhibitory effects on Mg2+-ATPase activity at low concentration (1 microM). 5. Our results suggest that most of the calcium antagonists studied have little effects on neuronal (Na+ + K+)-ATPase, Mg2+-ATPase and Ca2+-ATPase activities at therapeutic dose ranges (1 microM or lower). 相似文献