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61.
OBJECTIVE: Large volume paracentesis is an effective treatment for refractory ascites, but the need for routine infusion of albumin or other volume expanders remains controversial. The aim of this study was to assess the short term effects of a single 5-L paracentesis without albumin replacement on total central blood volume, systemic and renal hemodynamics, sodium homeostasis, and neurohumoral factors. PATIENTS AND METHODS: Twelve patients with biopsy-proven cirrhosis and tense, diuretic-resistant ascites were studied before and 48 h after a single 5-L paracentesis without albumin infusion. Systemic hemodynamics and total central blood volume were assessed using radionuclide angiography. Glomerular filtration rate and effective renal plasma flow were measured by inulin and para-aminohippurate clearances, respectively. Lithium clearance was used as an index of proximal tubular reabsorption of sodium. In addition, plasma concentrations of neurohumoral factors were determined. RESULTS: Total central blood volume was 2.41 +/- 0.33 L/m2 (mean +/- SEM) before and 2.34 +/- 0.18 L/m2 48 h after large volume paracentesis (p = 0.76). Similarly, no differences were detected in the cardiac index, glomerular filtration rate, effective renal plasma flow, urinary sodium excretion, hematocrit, plasma renin activity, or concentrations of plasma aldosterone, norepinephrine, or atrial natriuretic factor. CONCLUSIONS: A single large volume paracentesis without albumin replacement causes no disturbances in systemic and renal hemodynamics 48 h after the procedure. These results suggest that a single 5-L paracentesis without albumin infusion is a safe and satisfactory short term option for the management of patients with cirrhosis and tense, diuretic-resistant ascites.  相似文献   
62.
Immunocytochemistry and retrograde labeling were used to define the thalamic projections of calbindin- and parvalbumin-containing cells in superficial layers of the rat's superior colliculus (SC). Quantitative analysis revealed that 90.8 +/- 2.2% (mean +/- standard deviation) of the calbindin-immunoreactive neurons in the stratum griseum superficiale (SGS) projected to the dorsal lateral geniculate nucleus (LGNd) and that 91.3 +/- 4.3% of calbindin-immunoreactive neurons in the stratum opticum (SO) projected to the lateral posterior nucleus (LP). In contrast, only 17.3 +/- 2.5% of parvalbumin-immunoreactive neurons in the SGS were found to project to the LGNd and 16.5 +/- 3.1% of the parvalbumin-immunoreactive SO cells were retrogradely labeled after LP injections. Few of the parvalbumin-immunoreactive neurons in either the SGS (7.2 +/- 2.5%) or the SO (9.2 +/- 2.5%) were GABA positive. The retrograde-labeling results suggest that parvalbumin-immunoreactive neurons in the rat's SO and SGS may either be primarily interneurons or have descending projections, while calbindin-containing cells are primarily thalamic projection neurons. These results are consistent with data from other rodents, but almost exactly the opposite of data that have been reported for the cat for these same populations of SC projection neurons. Such interspecies differences raise questions regarding the functional importance of expressing one calcium-binding protein versus another in a specific neuronal population.  相似文献   
63.
Heatstroke represents the most severe form of the heat-related illnesses. Potentially fatal, heatstroke most often affects the elderly, obese, or chronically ill. Thyroid disease, which may interfere with the normal regulation of body temperature, has not previously been reported in cases of heatstroke. A fatal case is reported in a young woman discovered unconscious in a sauna who was found to have preexisting Hashimoto's thyroiditis on subsequent autopsy. The diagnosis of hypothyroidism in heatstroke rests on clinical information and morphologic observations. This case underscores the importance of evaluating the thyroid in unusual cases of heatstroke.  相似文献   
64.
Cardio-pulmonary function was measured in male broilers reared on diets formulated to contain 1.5% arginine (NORMAL group) or 2.5% arginine (ARGININE group). A snare placed around the right pulmonary artery permitted acute shunting of the entire cardiac output (CO) through the left pulmonary artery, resulting in sustained increases in blood flow (BF) through the left lung in both groups. The unilateral increase in BF was accompanied by sustained increases in pulmonary arterial pressure (PAP) and pulmonary vascular resistance (PVR) in the NORMAL group. However, following initial transient increases in PAP and PVR in the ARGININE group, subsequent pulmonary vasodilation gradually reduced PVR, and thus PAP, in spite of the ongoing elevation of BF through the left lung. The capacity of the pulmonary vasculature in the ARGININE group to accommodate an increased BF at a normal PAP accounts for the previously reported lower incidence of pulmonary hypertension syndrome (PHS, ascites) in cold-stressed broilers fed supplemental dietary arginine. Hypoxemia and respiratory acidosis ensued rapidly in both groups after tightening the pulmonary artery snare, in spite of a compensatory increase in the respiratory rate. The gradual return of PVR and PAP to presnare levels in the ARGININE group did not eliminate the concurrent ventilation-perfusion mismatch caused by the increased rate of BF through the left lung. Tightening the pulmonary artery snare caused mean systemic arterial pressure (MAP) to drop from control levels of approximately 98 mm Hg to sustained hypotensive levels of approximately 65 mm Hg in both groups. This systemic hypotension was caused by decreases in CO and total peripheral resistance (TPR). The reduction in CO were caused by reduction in stroke volume (SV) rather than heart rate (HR), suggesting that acutely tightening the pulmonary artery snare increased PVR sufficiently to impede left ventricular filling. Accordingly, the maximum increment in PAP attainable by the right ventricle during acute increases in PVR apparently was inadequate to propel the entire CO through the pulmonary vasculature, setting the stage for the congestive right-sided pooling of blood routinely associated with PHS in broilers.  相似文献   
65.
Buried p-buffer double heterostructure modulation-doped field-effect transistors (BP DH-MODFETs) with an InGaAs quantum-well channel were fabricated with high transconductance and good breakdown voltage, by placing the metal gate directly on Fe-doped InP insulating layer. Excellent extrinsic DC transconductance of 560 mS/mm and a high gate-to-drain diode breakdown voltage (greater than 20 V) were achieved at room temperature with FETs of 1.2-μm gate length. Unity currently gain cutoff frequency fT of 24 GHz and maximum oscillation frequency fmax of 60 GHz were demonstrated for a drain to source voltage VDS=4 V, which corresponds to an average electron velocity of 2.2×107 cm/s in the quantum well  相似文献   
66.
Various suggestions have been made for empirical pharmacodynamic indices of antibiotic effectiveness, such as areas under the drug concentration-time curve in serum (AUC), AUC > MIC, AUC/MIC, area under the inhibitory curve (AUIC), AUC above MIC, and time above MIC (T > MIC). In addition, bacterial growth and killing models, such as the Zhi model, have been developed. The goal of the present study was to compare the empirical behavior of the Zhi model of bacterial growth and killing with the other empirical pharmacodynamic indices described above by using simulated clinical data analyzed with the USC*PACK PC clinical programs for adaptive control of drug therapy, with one model describing a concentration-dependent antibiotic (tobramycin) and another describing a concentration-independent antibiotic (ticarcillin). The computed relative number of CFU was plotted against each pharmacodynamic index, with each axis parameterized over time. We assumed that a good pharmacodynamic index should present a clear and continuous relationship between the time course of its values and the time course of the bacterial killing as seen with the Zhi model. Preliminary work showed that some pharmacodynamic indices were very similar. A good sensitivity to the change in the values of the MIC was shown for AUC/MIC and also for T > MIC. In addition, the time courses of some other pharmacodynamic indices were very similar. Since AUC/MIC is easily calculated and shows more sensitivity, it appeared to be the best of the indices mentioned above for the concentration-dependent drug, because it incorporated and used the MIC the best. T > MIC appeared to be the best index for a concentration-independent drug. We also propose a new composite index, weighted AUC (WAUC), which appears to be useful for both concentration-dependent and concentration-independent drugs.  相似文献   
67.
68.
BACKGROUND: The results of palliative chemotherapy with cyclophosphamide, methotrexate and 5-fluorouracil (CMF) in patients with advanced breast cancer who received adjuvant therapy with the same regimen were investigated. RESULTS: Of 47 patients, 14 (30%) achieved an objective remission (median duration 9.5, range 5-21 months) and 8 (17%) stabilisation of disease (median duration 6, range 3-17 months). Objective remissions were observed in premenopausal as well as in postmenopausal women, in patients with all categories of dominant localisation of disease and regardless of the oestradiol receptor status of the primary tumour or eventual previous endocrine therapy. One of 4 and 13 of 43 patients who started palliative chemotherapy within or later than 12 months after the last adjuvant course obtained an objective remission. The median survival time from start of therapy of all treated patients was 12 (range 1-40) months. Patients with an objective remission or stable disease and patients with progressive disease had a median survival time of 20 (range 6-40) and 6 (range 1-35) months respectively (p < 0.0001). CONCLUSIONS: Palliative treatment with CMF should not be rejected for patients who have relapsed after adjuvant chemotherapy with the same modality.  相似文献   
69.
The EMS1 and CCND1 genes at chromosome 11q13 are amplified in about 15% of primary breast cancers but appear to confer different phenotypes in ER positive and ER negative tumours. Since there are no published data on EMS1 expression in large series of breast cancers we examined the relationship of EMS1 expression with EMS1 gene copy number and expression of mRNAs for cyclin D1 and ER. In a subset of 129 patients, where matched tumour RNA and DNA was available, EMS1 mRNA overexpression was associated predominantly with gene amplification (P = 0.0061), whereas cyclin D1 mRNA overexpression was not (P = 0.3142). In a more extensive series of 351 breast cancers, there was no correlation between cyclin D1 and EMS1 expression in the EMS1 and cyclin D1 overexpressors (P = 0.3503). Although an association between EMS1 mRNA expression and ER positivity was evident (P = 0.0232), when the samples were divided into quartiles of EMS1 or cyclin D1 mRNA expression, the increase in the proportion of ER positive tumours in the ascending EMS1 mRNA quartiles was not statistically significant (P = 0.0951). In marked contrast there was a significant stepwise increase in ER positivity in ascending quartiles of cyclin D1 mRNA (P = 0.030). A potential explanation for this difference was provided by the observation that in ER positive breast cancer cells oestradiol treatment resulted in increased cyclin D1 gene expression but was without effect on EMS1. The relationship between EMS1 expression and clinical outcome was examined in a subset of 234 patients with median follow-up of 74 months. High EMS1 expression was associated with age > 50 years (P = 0.0001), postmenopausal status (P = 0.0008), lymph node negativity (P = 0.019) and an apparent trend for worse prognosis in the ER negative subgroup. These data demonstrate that overexpression of EMS1 mRNA is largely due to EMS1 gene amplification, is independent of cyclin D1 and ER expression and, in contrast to cyclin D1, is not regulated by oestrogen. Independent overexpression of these genes may confer different phenotypes and disease outcomes in breast cancer as has been inferred from recent studies of EMS1 and CCND1 gene amplification.  相似文献   
70.
The suppression of apoptosis may contribute to the carcinogenicity of the peroxisome proliferators (PPs), a class of non-genotoxic rodent hepatocarcinogens. Our previous work demonstrated that the PP nafenopin suppressed both spontaneous and transforming growth factor beta1 (TGFbeta1)-induced hepatocyte apoptosis both in vivo and in vitro. Here, we extend these observations by demonstrating the ability of nafenopin to suppress apoptosis induced by other major candidates for the signalling of cell death in the liver. Treatment of rat or mouse hepatocyte monolayers with TGFbeta1 or the DNA damaging drugs etoposide or hydroxyurea induced high levels of apoptosis. Western blot analysis did not support a role for either p53 or p21waf1 in etoposide-induced apoptosis in rat hepatocytes. Treatment of mouse hepatocytes with an agonistic anti-Fas antibody also resulted in an induction of high levels of apoptosis. Pre-addition and continued exposure to nafenopin suppressed apoptosis induced by all three stimuli. Overall, our studies demonstrate that the ability of nafenopin to protect hepatocytes from apoptosis is not restricted to species or apoptotic stimulus. It is possible, therefore, that the PPs may suppress apoptosis by acting on diverse signalling pathways. However, it seems more likely that nafenopin suppresses hepatocyte apoptosis elicited by each death stimulus by impinging on a core apoptotic mechanism.  相似文献   
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