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51.
Three different fully implantable venous access devices were randomly inserted in 72 patients. Comparison both from the point of view of their ease of insertion and their later use failed to show any significant difference between the three systems.  相似文献   
52.
Two cases of fibromatosis of the breast, characterized by a proliferation of spindle cells containing intracytoplasmic, spherical, eosinophilic inclusion bodies, are reported. The light and electron microscopic features, as well as the immunohistochemical features, are indistinguishable from those found in infantile digital fibromatosis. The proliferating spindle cells are characterized as myofibroblasts, whereas the inclusion bodies show an immunohistochemically nonreactive, hollow-like pattern with peripheral reactivity for actin filaments. This lesion, observed for the first time in the breast, expands the number of extradigital inclusion body fibromatoses.  相似文献   
53.
The G protein beta5 subunit differs substantially in amino acid sequence from the other known beta subunits suggesting that beta gamma dimers containing this protein may play specialized roles in cell signaling. To examine the functional properties of the beta5 subunit, recombinant beta5 gamma2 dimers were purified from baculovirus-infected Sf9 insect cells using a strategy based on two affinity tags (hexahistidine and FLAG) engineered into the N terminus of the gamma2 subunit (gamma2HF). The function of the pure beta5 gamma2HF dimers was examined in three assays: activation of pure phospholipase C-beta in lipid vesicles; activation of recombinant, type II adenylyl cyclase expressed in Sf9 cell membranes; and coupling of alpha subunits to the endothelin B (ETB) and M1 muscarinic receptors. In each case, the efficacy of the beta5 gamma2HF dimer was compared with that of the beta1 gamma2HF dimer, which has demonstrated activity in these assays. The beta5 gamma2HF dimer activated phospholipase C-beta with a potency and efficacy similar to that of beta1 gamma2 or beta1 gamma2HF; however, it was markedly less effective than the beta1 gamma2HF or beta1 gamma2 dimer in its ability to activate type II adenylyl cyclase (EC50 of approximately 700 nM versus 25 nM). Both the beta5 gamma2HF and the beta1 gamma2HF dimers supported coupling of M1 muscarinic receptors to the Gq alpha subunit. The ETB receptor coupled effectively to both the Gi and Gq alpha subunits in the presence of the beta1 gamma2HF dimer. In contrast, the beta5 gamma2HF dimer only supported coupling of the Gq alpha subunits to the ETB receptor and did not support coupling of the Gi alpha subunit. These results suggest that the beta5 gamma2HF dimer binds selectively to Gq alpha subunits and does not activate the same set of effectors as dimers containing the beta1 subunit. Overall, the data support a specialized role for the beta5 subunit in cell signaling.  相似文献   
54.
OBJECTIVES: Identify factors predicting favorable outcome after medical management of valve ring abscesses in order to propose a surveillance schedule for conservative treatment. METHODS: A multicentric study conducted from July 1989 to February 1996 included 28 patients (mean age 64 +/- 16 years, range 26-83) hospitalized for active endocarditis and valve ring abscesses diagnosed at transthoracic or transesophageal echography. Conservative medical therapy was given because of a decision of the medico-surgical team (n = 9), high surgical risk (n = 12), or patient refusal of surgery (n = 7). Outcome was favourable in 18 patients (Group I) and unfavorable in 10 (Group II) due to death (n = 9) or subsequent surgery (n = 1). Univariate and multivariate analysis were used to determine differences between the groups in terms of clinical and laboratory data. RESULTS: Mean follow-up in Group I was 33 +/- 18 months and 15 +/- 10 months in Group II. Univariate analysis showed significant differences between Group I and II respectively for age (59 +/- 18 yr vs 72 +/- 10, p = 0.04), delay to apyrexia after antibiotics (4.3 +/- 2.8 vs 8.3 +/- 2.4 days, p < 0.0008), heart failure (5% vs 70%, p = 0.003), grade III or IV valvular regurgitation (5% vs 60%, p < 0.04), and mean surface area of the abscess (1.5 +/- 1.2 vs 5.4 +/- 6.4 cm2, p < 0.03). Independent factors at multivariate analysis were by decreasing order: lack of heart failure at admission, delay to apyrexia, abscess surface area, and age. Outcome was favorable (mean follow-up 33 +/- 10 months) in all patients with an abscess surface area < 1.5 cm2, no signs of heart failure, no grade III or IV valvular regurgitation, apyrexia after less than 8 days on antibiotics and no staphylococcus positive blood culture. CONCLUSION: Medical management of valve ring abscesses may be indicated in selected patients in care units with rigorous surveillance facilities. Further studies are needed to precisely identify surveillance and treatment criteria.  相似文献   
55.
BACKGROUND: Hearing loss is generally regarded as a rare side effect of erythromycin therapy. However, our own clinical experiences in erythromycin-treated patients led us to suspect that this complication may be more common among renal allograft recipients. The purpose of this study was to evaluate the incidence, predisposing factors, clinical characteristics, and outcomes of erythromycin-induced hearing loss among renal allograft recipients. METHODS: We reviewed medical records of renal transplant patients treated for pneumonia with intravenous erythromycin lactobionate. Patients were evaluated for the occurrence of clinically significant hearing loss (including onset, duration, and reversibility), other signs and symptoms of ototoxicity (vertigo and tinnitus), daily erythromycin dose and duration of treatment, concurrent ototoxic drug therapy, renal and hepatic function, and history of previous otic disease. RESULTS: Eleven (32%) of 34 courses of intravenous erythromycin therapy resulted in hearing loss. The incidence of hearing loss was 53% (eight of 15 courses) in patients treated with 4 g of erythromycin daily compared with 16% (three of 19 courses) among those receiving 2 g/d (P = .05). In addition, courses of erythromycin were longer in those suffering auditory toxicity (9.6 +/- 4.7 days) than in nontoxic patients (5.7 +/- 3.6 days) (P < .05). Hepatic and renal function did not differ between toxic and nontoxic patients. All episodes of erythromycin-induced hearing loss were reversible. CONCLUSIONS: We conclude that clinically significant hearing loss occurs in more than 30% of renal allograft recipients treated for pneumonia with intravenous erythromycin lactobionate. Patients who require prolonged courses of erythromycin and those treated with 4 g/d are at particular risk for the development of auditory toxicity. With prompt recognition and modification of therapy, erythromycin-induced hearing loss appears to be completely reversible.  相似文献   
56.
57.
This study examined organizational family-responsive policies, perceptions of the organization as family supportive, and supervisor support as issues that may be salient to the experience of conflict between paid employment (work) and family roles. Data were collected from 355 managerial personnel in New Zealand. Although work-family conflict and psychological strain were strongly linked, the availability of organizational policies had no significant association with levels of conflict or strain, whereas policy usage was related only to work-to-family interference and not to family-to-work interference. On the other hand, perceptions of the organization as family supportive and supervisor support for work-family balance displayed significant relationships with key variables, highlighting the importance of these variables for interventions designed to ameliorate the negative impact of work-family conflict on managerial well-being. Implications for the effective implementation of family-responsive interventions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
58.
59.
The Haemocell S-350 device has recently been introduced for intraoperative autotransfusion. The system uses a novel membrane filter to process shed blood. In the first part of this study a 0.2-micron pore size filter was used in a randomized trial comparing the use of autotransfusion (n = 8) with bank blood controls (n = 9) during aortic reconstruction. This part of the trial was abandoned because of unexpected non-surgical bleeding. Bank blood requirements fell from a median of 3.0 (range 0.0-9.0) units to 1.5 (range 0.0-7.0) units when autotransfusion was used, but these patients had a greater perioperative blood loss (1791 (range 932-3104) versus 1140 (range 440-3840) ml). There was evidence of postoperative heparin excess with an activated partial thromboplastin time ratio of 1.3 (range 0.9-3.0) versus 1.0 (range 1.0-1.2) in controls and an activated clotting time of 206 (range 143-280) versus 137 (range 107-142) s. This was confirmed by raised plasma heparin levels and a prolonged thrombin time normalized by protamine. To improve performance a 0.6-micron pore size filter was studied in ten patients. Filtration efficiency doubled from 19 to 38 per cent. Electron micrographs demonstrated better filter clearance, but 44 per cent of the original concentration of heparin remained in the reinfusate. The S-350 device may be an attractive alternative to centrifugation for intraoperative autotransfusion but, until efficiency is improved, it should only be used for cardiovascular surgery when excess heparin can be reversed with protamine.  相似文献   
60.
The change of foot length and width with age has been reported in a few anthropometric studies in the literature. However, the relationship with body height rarely is reported, and the dynamic effect of weightbearing on foot size has not been documented. In this series, 2829 children 3 to 18 years of age of equal gender distribution were included in the study. The foot length and width on weightbearing and nonweightbearing were measured with a special precision electronic caliper. The foot length and width were found to increase linearly from the age of 3 years until 12 years in girls and 15 years in boys. This was followed by a phase during which the increase plateaued. The foot length and width increased significantly on weightbearing at all ages in both genders with a mean of 2.1 to 4.4 mm or 3.1% to 4.8%, respectively. The foot length and width also were found to correlate significantly with the body height in both genders, with a correlation coefficient of 0.96 to 0.98. No significant differences were found between the sizes of the dominant and nondominant foot in either gender.  相似文献   
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