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61.
Renal echography (RE) is a well recognized, accurate, non-invasive imaging procedure for detecting urinary tract (UT) obstruction in Intensive Care Unit (ICU) patients: a dilated collecting system is usually present but a few cases of nondilated obstructive nephropathy have been previously described. We report the clinical, biological, imaging procedure data and outcome of 6 additional cases of anuric obstructive nephropathy without dilatation on one or more RE. All patients had previous and/or actual history suggestive of UT obstruction. Retrograde ureteropyelography (RUP) was performed in all of them: it provided the diagnosis of obstruction in 4 and was immediately followed by dramatic improvement of renal function in all, including the 2 patients with septic shock from proven or suspected UT origin. The cause of obstruction was a neoplastic retroperitoneal process in 4. We conclude that anuric nondilated obstructive renal failure is not uncommon and should be considered in anuric patients when UT obstruction is likely to occur. The sole visualization of a non-dilated collecting system on RE should lead to repeat RE, especially in hypovolemic anuric patients. RUP provided immediate diagnostic and therapeutic benefits in comparison with other imaging procedures in our series.  相似文献   
62.
In the case of 17 obstetrical facial paralyses occurring in a total of 20,409 births, the authors have studied the circumstances of their appearance and the prognosis for this lesion. It is a rare lesion favoured by asymmetric purchase when using articulated forceps. The authors insist that use of Thierry's forceps do not harm the facial nerve. They emphasise the possibility that progression may not always be favourable.  相似文献   
63.
Adenylate cyclase activity was studied in anterior pituitary homogenates from young adult (6 months) and old (20 and 24 months) male rats. Basal, NaF-, GTP-, 5'-guanylimidodiphosphate (Gpp(NH)p)- and forskolin-stimulated activities were similar in the three groups, implying that the stimulatory guanyl nucleotide regulatory binding site (NS) and the catalytical unit were unaffected by aging. Vasoactive intestinal peptide (VIP)-stimulated adenylate cyclase activity was also identical in the three groups. The efficacy (i.e., the maximum effect) of growth hormone-releasing factor [GRF(1-29)-NH2] on adenylate activity was reduced by 45-49% in old and senescent rats with no change in peptide potency (i.e., the concentration required for half-maximal enzyme stimulation). These results suggest that aging induced a selective loss of functional GRF receptors but influenced neither the coupling between receptors, NS and the catalytic unit nor the efficacy of the catalytic unit per se.  相似文献   
64.
We analyzed the competition kinetics of quinuclidinyl benzilate (QNB) and QNB methiodide enantiomers on human NB-OK1 neuroblastoma (M1), rat cardiac (M2), and rat pancreas (M3) muscarinic binding sites. The association rate constants of the four drugs depended on the receptor subtype studied and were lower with pancreas (M3) (1-9 x 10(5) M-1 sec-1) than with cardiac (M2) (1-5 x 10(6) M-1 sec-1) and NB-OK1 (M1) (1-5 x 10(6) M-1 sec-1) binding sites. At each receptor subtype, we observed no significant difference between the association rate constants of the R- and S-enantiomers of either QNB or QNB methiodide. Receptor stereoselectivity, when present, was associated with differences in unlabeled drug dissociation rate constants. The dissociation rate constant varied much more than the association rate constant, when either (R)-QNB dissociation from the three subtypes (half-life, 77 min to greater than 340 min; best fit, 40 days) or dissociation of the four drugs from each receptor subtype (half-lives varying from 1.4 min to 4 hr at M1 receptors, 1.1 to 77 min at M2 receptors, and 3.5 min to greater than 340 min at M3 receptors were obtained by competition kinetics analysis) was compared.  相似文献   
65.
OBJECTIVE: The use of topical polymyxin and tobramycin to prevent intensive care infections is controversial. Moreover, these antibiotics are ineffective against methicillin-resistant Staphylococcus aureus. A decontamination regimen using mupirocin and chlorhexidine could prevent acquired infections, including those involving S. aureus. Because these two regimens could have a complementary role, we evaluated their effects when given both alone and combined. DESIGN: The authors conducted a multiple-center, placebo-controlled, randomized, double-blind study performed according to a 2 x 2 factorial design. SETTING: The study was conducted at three polyvalent medical intensive care units at university-affiliated hospitals in France. PATIENTS: Adult patients (age, > or =18 yrs) intubated for <48 hrs who were likely to be ventilated for >48 hrs. INTERVENTION: Two regimens were used: topical administration of polymyxin/tobramycin (or placebo) and nasal mupirocin with chlorhexidine body washing (or nasal placebo with liquid soap). The patients (n = 515) received polymyxin/tobramycin alone (n = 130), mupirocin/chlorhexidine alone (n = 130), both regimens (n = 129), or all placebos (n = 126) for the period of mechanical ventilation plus 24 hrs. MEASUREMENTS AND MAIN RESULTS: The incidence of total infections acquired from the date of randomization until the termination date of study treatments plus 48 hrs was assessed. There were fewer acquired infections with both regimens than with polymyxin/tobramycin alone (odds ratio, 0.44; 95% confidence interval, 0.26-0.75; p = .003), mupirocin/chlorhexidine alone (0.43; 0.25-0.73; p = .002), or all placebos (0.42; 0.25-0.72; p = .001). There were no differences between polymyxin/tobramycin alone (0.95; 0.59-1.54; p = .84) and mupirocin/chlorhexidine alone (0.98; 0.60-1.58; p = .92) vs. all placebos. The probability of freedom from infection was higher with both regimens than with polymyxin/tobramycin alone (p = .002), mupirocin/chlorhexidine alone (p < .001), or all placebos (p < .001). Infection rates were also significantly lower with both regimens than with polymyxin/tobramycin alone (p = .017), mupirocin/chlorhexidine alone (p < .001), or all placebos (p < .001). CONCLUSION: Acquired infections were substantially reduced by mupirocin/chlorhexidine plus polymyxin/tobramycin, whereas each regimen given alone was ineffective. Whether both regimens could increase Candida infections deserves further investigation.  相似文献   
66.
Introduction: Diffuse large B-cell lymphomas (DLBCL) represent a heterogeneous subset of non-Hodgkin lymphomas (NHL) that demonstrate many molecular alterations and somatic mutations, all of which are targets for the recent development of biomarkers that use various molecular biological techniques. These non-invasive emerging biomarkers will be used in the next few years to better monitor the response to immunochemotherapeutic treatments with the aim of completely eradicating the disease in order to cure it.

Areas covered: In this review, the authors conducted a literature search to identify and summarize the major advances in liquid biopsy techniques for DLBCL that are useful for diagnosis and monitoring minimal residual disease (MRD). The authors report on the major technological leaps represented by the main MRD tools (sequencing of clone-specific rearrangements of immunoglobulin genes and sequencing of somatic mutations in circulating tumor plasma DNA) and present the expected future developments and the impact of these new tools on clinical practice.

Expert commentary: The monitoring of somatic mutations in tumor plasma cell-free DNA represents a promising tool for liquid biopsy, which will in the future allow non-invasive monitoring that will be used at any time to follow the response to the treatment.  相似文献   

67.
Procalcitonin: a valuable indicator of infection in a medical ICU?   总被引:11,自引:0,他引:11  
OBJECTIVE: To assess the use of procalcitonin (PCT) for the diagnosis of infection in a medical ICU. DESIGN: Prospective, observational study. PATIENTS: Seventy-seven infected patients and 24 patients with systemic inflammatory response syndrome (SIRS) due to other causes. Seventy-five patients could be classified into sepsis (n = 24), severe sepsis (n = 27) and septic shock (n = 24), and 20 SIRS patients remained free from infection during the study. Plasma PCT and C-reactive protein (CRP) levels were evaluated within 48 h of admission (day 0), at day 2 and day 4. RESULTS: As compared with SIRS, PCT and CRP levels at day 0 were higher in infected patients, regardless of the severity of sepsis (25.2 +/- 54.2 ng/ml vs 4.8 +/- 8.7 ng/ml; 159 +/- 92 mg/l vs 71 +/- 58 mg/l, respectively). At cut-off values of 2 ng/ml (PCT) and 100 mg/l (CRP), sensitivity and specificity were 65% and 70% (PCT), 74% and 74% (CRP). PCT and CRP levels were significantly more elevated in septic shock (38.5 +/- 59.1 ng/ml and 173 +/- 98 mg/l) than in SIRS (3.8 +/- 6.9 ng/ml and 70 +/- 48 mg/l), sepsis (1.3 +/- 2.7 ng/ml and 98 +/- 76 mg/l) and severe sepsis (9.1 +/- 18. 2 ng/ml and 145 +/- 70 mg/l) (all p = 0.005). CRP, but not PCT, levels were more elevated in severe sepsis than in SIRS (p<0.0001). Higher PCT levels in the patients with four dysfunctional organs and higher PCT and CRP levels in nonsurvivors may only reflect the marked inflammatory response to septic shock. CONCLUSION: In this study, PCT and CRP had poor sensitivity and specificity for the diagnosis of infection. PCT did not clearly discriminate SIRS from sepsis or severe sepsis.  相似文献   
68.
Objective To assess the efficacy, adverse effects and relevance of calcium-free hemodialysis (CFHD) in the treatment of major hypercalcemia.Design Retrospective chart review.Setting Medical ICU.Patients All patients admitted over a 9-year period for hypercalcemia requiring urgent treatment and who underwent hemodialysis.Interventions CFHD with an acetate dialysate.Main results Thirty-three patients with severe hypercalcemia from various etiologies received CFHD. Marked and rapid decrease of serum total calcium was obtained during all sessions (mean decrease: 1.71±0.54 mmol/l). Calcium rebound within 24 h after CFHD was observed in all evaluable cases (1±0.45 mmol/l; mean delay 13.7±5.8 h). Adverse cardiovascular effects occurred in 17 of 48 sessions (35%) and in 13 of 30 evaluable patients (43%).Conclusions Adverse effects are frequent during CFHD. After correction of hypovolemia, its use should be restricted to patients with severe clinical symptoms or advanced renal impairment.  相似文献   
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