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131.
Background and hypothesis: It is not fully understood whether alterations in left ventricular (LV) relaxation in patients with idiopathic dilated cardiomyopathy (DCM) precede or follow alterations in LV systolic function. Accordingly, we investigated the relationship between LV systole and diastolic relaxation in patients with DCM using LV pressure-volume analysis. Methods: Hemodynamic data were collected for 38 consecutive patients with DCM in normal sinus rhythm and in the resting steady state (New York Heart Association functional class II to III). Continuous simultaneous pressure-volume relationships were obtained by conductance catheter. Left ventricular end-systolic elastance (Ees) was determined during transient occlusion of the inferior vena cava. Results: Left ventricular ejection fraction, peak negative dP/dt, and peak positive dP/dt were depressed (31 ± 11%, - 1242 ± 351 mmHg/s, and 1118 ±253 mmHg/s, respectively ). The LV end-diastolic volume index, the time constants of isovolumic LV pressure decay Tl and Td were increased (141 ±38 ml/m2, 54+14 ms, and 69 ± 17 ms, respectively). Ees was markedly depressed (0.9 ± 0.5 mmHg/ml) and was not correlated with established systolic or diastolic indices except for peak positive dP/dt. Our results showed that abnormalities of relaxation were not correlated with contractile dysfunction in patients with DCM in the resting steady state however, most patients (79%) had both prolonged relaxation and extremely depressed contractility. Abnormal relaxation may have been transient or compensated in some patients (21%) with DCM who had preserved relaxation despite severely depressed contractility.  相似文献   
132.
OBJECTIVE: To investigate the hypothesis that repeated arousals at the termination of apnea/hypopnea in obstructive sleep apnea syndrome (OSAS) are related to abnormal circadian rhythm of blood pressure (BP). DESIGN AND METHODS: We performed polysomnography (PSG) with pulse oximetry in 26 middle-aged patients with OSAS aged 42-58 years (mean age 51.8 years). The intensity of arousal on PSG was graded into two levels: grade 1 (EEG arousal, EA), an abrupt shift in EEG frequency, and grade 2 (movement arousal, MA), EEG arousal with an increase in electromyogram activity lasting at least 3 s. The number of apnea/hypopneas per hour (apnea/hypopnea index, AHI), and length of time during which nocturnal oxygen saturation decreased below 90% (oxygen desaturation time, ODT) were also evaluated. Percentage EA and %MA were assessed by the ratio of the number of apneas and hypopneas with EA or MA to the number of apneas and hypopneas in total. The 24 h systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured noninvasively. Multiple regression analysis was performed among AHI, ODT, %EA and %MA or among age, body mass index and %MA. RESULTS: The %MA was the most significant factor contributing to the elevated 24 h SBP (r= 0.46, P< 0.05); oxygen desaturation (r= 0.44, P< 0.05) was the next most important contributing factor. The level and pattern of 24 h BP differed significantly between the patients with %MA 85% and %MA < 85% (mean 24 h SBP: 147 +/- 16.8 versus 125 +/- 19.6 mmHg, P< 0.01; mean 24 h DBP: 97.5 +/- 14.3 versus 85.6 +/- 14.6 mmHg, P< 0.01), and also differed between those with severe OSAS, i.e. ODT > or = 130 min, and mild to moderate OSAS, i.e. ODT < 130 min, (mean 24 h SBP: 149 +/- 15.8 versus 132 +/- 20.6 mmHg, P < 0.01; mean 24 h DBP: 100 +/- 14.1 versus 87.4 +/- 14.0 mmHg, P < 0.01). CONCLUSION: Our findings suggest that MA and oxygen desaturation in OSAS make an important contribution to abnormal circadian rhythm of BP. We conclude that repeated end-apneic arousal and/or hypoxic asphyxia and the subsequent sleep fragmentation may contibute to nocturnal and diurnal elevation of BP.  相似文献   
133.
Bone lesions in elderly multiple myeloma   总被引:2,自引:0,他引:2  
We investigated the incidence of bone lesions in elderly cases of multiple myeloma (MM) and the course of those lesions, and also evaluated the relationships of skeletal symptoms with prognostic factors, and prognosis. The subjects were 146 patients, aged 65 years or more (median age 74, range 65-97 year), who were admitted to 11 institutions between January, 1988 and December, 1997. They consisted of 64 men and 82 women. The disease type was IgG type in 88 patients, IgA type in 37 patients, Bence-Jones (BJ) type in 17 patients, IgD type in three patients, and non-secretory type in one patient. Bone lesions in elderly MM patients were compared with those in 65 non-elderly MM patients. Skeletal symptoms were noted in 104 patients, and bone pain in 75 patients at the time of diagnosis. The bone lesions were evaluated as only osteolytic lesions in 26 patients, osteolytic lesions + osteoporosis in 23 patients, only osteoporosis in 2 patients and pathologic bone fractures in 53 patients. The occurrence rate of osteoporosis plus osteolytic lesion was higher in elderly patients (63.5%) than that in non-elderly patients (NE-MM group) (28.3%) (p < 0.0001). The bone lesions were most often observed in lumbar vertebrae (58.7%), cranial bone (56.7%), thoracic vertebrae (40.4%) and ribs (27.9%). The occurrence rate of bone lesion in lumbar vertebrae was higher in elderly patients (58.7%) than that in non-elderly patients (22.6%) (p < 0.0001). The life activities were limited in 71 patients because of the bone lesions. The relationship between the prognostic factors of MM and bone lesions was evaluated. There was a significant difference in the serum Ca level between patients with and without bone pain (P < 0.0001) and between those with and without pathologic bone fracture (P < 0.01). There was a significant difference in the appearance rate of plasma cells in the bone marrow between the patients with and without bone lesions (P < 0.05), between those with and without bone pain (P < 0.01), and between those with and without pathologic fracture (P < 0.05). There was a significant difference in the serum beta 2-microglobulin level between the patients with and without bone pain, and between those with and without pathologic fracture. There were no significant differences in survival times between elderly MM patients with and without bone lesions, bone pain and pathological bone fractures, while significant differences of survival times were found between non-elderly MM patients with and without bone lesions, bone pain and pathological bone fractures (P < 0.05, each). These data suggest that there are some differences in bone lesions between elderly and non-elderly MM patients.  相似文献   
134.
The cell-cycle status of hematopoietic stem and progenitor cells (HSPCs) becomes activated following chemotherapy-induced stress, promoting bone marrow (BM) regeneration; however, the underlying molecular mechanism remains elusive. Here we show that BM-resident group 2 innate lymphoid cells (ILC2s) support the recovery of HSPCs from 5-fluorouracil (5-FU)–induced stress by secreting granulocyte-macrophage colony-stimulating factor (GM-CSF). Mechanistically, IL-33 released from chemo-sensitive B cell progenitors activates MyD88-mediated secretion of GM-CSF in ILC2, suggesting the existence of a B cell–ILC2 axis for maintaining hematopoietic homeostasis. GM-CSF knockout mice treated with 5-FU showed severe loss of myeloid lineage cells, causing lethality, which was rescued by transferring BM ILC2s from wild-type mice. Further, the adoptive transfer of ILC2s to 5-FU–treated mice accelerates hematopoietic recovery, while the reduction of ILC2s results in the opposite effect. Thus, ILC2s may function by “sensing” the damaged BM spaces and subsequently support hematopoietic recovery under stress conditions.  相似文献   
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A 13 year-old girl with Down's syndrome was admitted to our hospital with a very positive reaction to PPD 5TU, abnormal shadow on the chest X-ray films and diarrhea. She suffered from acute enterocolitis one year ago, and then has been complaining of abdominal pain, appetite loss, and weight loss for a year. After admission, she was diagnosed as tuberculous pleuritis and suspected intestinal tuberculosis by laboratory examination. She recovered without sequelae by the combination therapy of SM, INH, and RFP, and was discharged after 5 months. The diagnosis of intestinal tuberculosis was confirmed by Colon Fiberscopy showing ulceration at the ileocecal region and simultaneous biopsy showing granuloma. Surgical treatment was not reserved, because she had no complications namely perforation and fistulization. We estimated that the onset of intestinal tuberculosis coincided with the acute enterocolitis which she had about one year ago. We realized the importance of paying attention to intestinal tuberculosis in the differential diagnosis of enterocolitis, especially regional enteritis. Furthermore, in the therapy of the immunocompromised host including Down's syndrome, we must pay attention to extra-pulmonary tuberculosis. Efficiency of SM for intestinal tuberculosis with complications was confirmed.  相似文献   
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