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BACKGROUND: Early diagnosis and treatment of intra-abdominal pathology in critically ill intensive care unit (ICU) patients remains a clinical challenge. The objective of this study is to assess the feasibility of portable, bedside diagnostic laparoscopy (DL) in the ICU for patients suspected of intra-abdominal pathology, and to contrast its accuracy with diagnostic peritoneal lavage (DPL). METHODS: All adult ICU patients for whom a general surgery consultation was requested were eligible. Patients with a recent laparotomy or obvious peritonitis were excluded. All procedures were performed in the ICU. RESULTS: Over a consecutive 16-month period, 12 patients underwent DPL/DL. Ages ranged from 28 to 88 (mean, 72) years. Causative findings were disclosed by DL in five patients, (42%) including intestinal ischemia in two. Perforated diverticulitis, thickened terminal ileum, and nonpurulent peritonitis were found in one patient each. All patients with findings by DL had a positive DPL (WBC > 200 cells/mm3), and one negative laparoscopy was positive by lavage. The average length of time to perform DPL was 14 min, and to complete DL 19 min. One patient underwent laparotomy based on DPL/DL and survived along with three others with negative DPL/DL. Eight patients died (67%), four from their surgically untreated intra-abdominal pathology. One patient sustained a procedure-related complication of bradycardia and high ventilatory airway pressures. Peak airway pressures increased an average of 8 mmHg and were significantly higher (p < 0. 001) than pre-DL pressures without any significant change in end-tidal CO2 or pCO2. There were no statistically significant hemodynamic changes based on mean arterial pressure (MAP), central venous pressure (CVP), or pulmonary artery diastolic pressure (PADP). CONCLUSIONS: Bedside laparoscopy can be performed rapidly and safely in the ICU. In predicting the need for laparotomy, DL was more accurate than DPL. 相似文献
104.
Absorbable stapling devices have been described by several groups for the creation of continent urinary diversions. Experience with these devices in the creation of the LeBag ileocecal orthotopic pouch is described. Use of the staplers simplifies pouch construction and yields functional results similar to hand-sewn reservoirs. 相似文献
105.
Z Zhu J Yao T Johns K Fu I De Bie C Macmillan AP Cuthbert RF Newbold J Wang M Chevrette GK Brown RM Brown EA Shoubridge 《Canadian Metallurgical Quarterly》1998,20(4):337-343
A drug with cationic characteristics such as procaine can be conveyed in a Carbomer hydrogel in two different ways: (i) in the form of salt in solution in the aqueous phase, and (ii) in the base form salified with the same polymer. Introduction of the drug into the hydrogel with different concentrations of polymer produced, in both cases, a reduction in viscosity in relation to drug concentration. The gels with procaine salified with the polymer showed greater viscosity. The drug release rate, in general, diminished with the increase in polymer concentration. Nevertheless, when this concentration was maintained, there was no variation in release rate when the viscosity produced as a consequence of drug concentration was changed. Gels with procaine salified with the carboxyvinylic polymer had a faster release rate than those with procaine in the hydrochloride form dissolved in the aqueous phase. These results have also been confirmed by a simulated absorption test. 相似文献
106.
RA Larson RK Dodge CA Linker RM Stone BL Powell EJ Lee P Schulman FR Davey SR Frankel CD Bloomfield SL George CA Schiffer 《Canadian Metallurgical Quarterly》1998,92(5):1556-1564
Recombinant human granulocyte colony-stimulating factor (G-CSF; filgrastim) shortens the time to neutrophil recovery after intensive chemotherapy, but its role in the treatment of adults with acute lymphoblastic leukemia (ALL) is uncertain. We randomly assigned 198 adults with untreated ALL (median age, 35 years; range, 16 to 83) to receive either placebo or G-CSF (5 microgram/kg/d) subcutaneously, beginning 4 days after starting intensive remission induction chemotherapy and continuing until the neutrophil count was >/=1, 000/microL for 2 days. The study assignment was unblinded as individual patients achieved a complete remission (CR). Patients initially assigned to G-CSF then continued to receive G-CSF through 2 monthly courses of consolidation therapy. Patients assigned to placebo received no further study drug. The median time to recover neutrophils >/=1,000/microL during the remission induction course was 16 days (interquartile range [IQR], 15 to 18 days) for the patients assigned to receive G-CSF and 22 days (IQR, 19 to 29 days) for the patients assigned to placebo (P < .001). Patients in the G-CSF group had significantly shorter durations of neutropenia (<1, 000/microL) and thrombocytopenia (<50,000/microL) and fewer days in the hospital (median, 22 days v 28 days; P = .02) compared with patients receiving placebo. The patients assigned to receive G-CSF had a higher CR rate and fewer deaths during remission induction than did those receiving placebo (P = .04 by the chi-square test for trend). During Courses IIA and IIB of consolidation treatment, patients in the G-CSF group had significantly more rapid recovery of neutrophils >/=1,000/microL than did the control group by approximately 6 to 9 days. However, the patients in the G-CSF group did not complete the planned first 3 months of chemotherapy any more rapidly than did the patients in the placebo group. Overall toxicity was not lessened by the use of G-CSF. After a median follow-up of 4. 7 years, there were no significant differences in either the disease-free survival (P = .53) or the overall survival (P = .25) for the patients assigned to G-CSF (medians, 2.3 years and 2.4 years, respectively) compared with those assigned to placebo (medians, 1.7 and 1.8 years, respectively). Adults who received intensive chemotherapy for ALL benefited from G-CSF treatment, but its use did not markedly affect the ultimate outcome. 相似文献
107.
Parotid gland dysfunction in a murine model of acute graft versus host disease [aGVHD] 总被引:1,自引:0,他引:1
We report a rare case of meningeal melanocytoma in the left frontal region. A 45-year-old man complained of a headache. Magnetic resonance (MR) scanning showed characteristic patterns: a slightly high signal intensity mass in the left frontal region on the T1-weighted image and a low signal intensity on the T2-weighted image. The patient underwent gross total removal of the tumor. The postoperative course was uneventful. After two years, there was a small local recurrence. The histological finding of the tumor showed meningeal melanocytoma. To our knowledge, this is the second published report of a meningeal melanocytoma in the supratentorial region. 相似文献
108.
B Errede RM Cade BM Yashar Y Kamada DE Levin K Irie K Matsumoto 《Canadian Metallurgical Quarterly》1995,42(4):477-485
In the budding yeast, Saccharomyces cerevisiae, four separate but structurally related mitogen-activated protein kinase (MAPK) activation pathways are known. The best understood of these regulates mating. Pheromone binding to receptor informs cells of the proximity of a mating partner and induces differentiation to a mating competent state. The MAPK activation cascade mediating this signal is made up of Ste11 (a MEK kinase [MEKK]), Ste7 (a MAPK/ERK kinase [MEK]), and the redundant MAPK-related Fus3 and Kss1 enzymes. Another MAPK activation pathway is important for cell integrity and regulates cell wall construction. This cascade consists of Bck1 (a MEKK), the redundant Mkk1 and Mkk2 enzymes (MEKs), and Mpk1 (a MAPK). We exploited these two pathways to learn about the coordination and signal transmission fidelity of MAPK activation cascades. Two lines of evidence suggest that the activities of the mating and cell integrity pathways are coordinated during mating differentiation. First, cells deficient in Mpk1 are susceptible to lysis when they make a mating projection in response to pheromone. Second, Mpk1 activation during pheromone induction coincides with projection formation. The mechanism underlying this coordination is still unknown to us. Our working model is that projection formation generates a mobile second messenger for activation of the cell integrity pathway. Analysis of a STE7 mutation gave us some unanticipated but important insights into parameters important for fidelity of signal transmission. The Ste7 variant has a serine to proline substitution at position 368. Ste7-P368 has higher basal activity than the wild-type enzyme but still requires Ste11 for its function. Additionally, the proline substitution enables the variant to transmit the signal from mammalian Raf expressed in yeast. This novel activity suggests that Ste7-P368 is inherently more permissive than Ste7 in its interactions with MEKKs. Yet, Ste7-P368 cross function in the cell integrity pathway occurs only when it is highly overproduced or when Ste5 is missing. This behavior suggests that Ste5, which has been proposed to be a tether for the kinases in the mating pathway, contributes to Ste7 specificity and fidelity of signal transmission. 相似文献
109.
Influence of compaction on the interfacial transition zone and the permeability of concrete 总被引:2,自引:0,他引:2
Andreas Leemann Beat Münch Philippe Gasser Lorenz Holzer 《Cement and Concrete Research》2006,36(8):1425-1433
The interfacial transition zone (ITZ) is regarded as a key feature for the transport properties and the durability of concrete. In this study one self-compacting concrete (SCC) mixture and two conventionally vibrated concrete (CVC) mixtures are studied in order to determine the influence of compaction on the porosity of the ITZ. Additionally oxygen permeability and water conductivity were measured in vertical and horizontal direction. The quantitative analysis of images made with an optical microscope and an environmental scanning electron microscope shows a significantly increased porosity and width of the ITZ in CVC compared to SCC. At the same time oxygen permeability and water conductivity of CVC are increased in comparison to SCC. Moreover, considerable differences in the porosity of the lower, lateral and upper ITZ are observed in both types of concrete. The anisotropic distribution of pores in the ITZ does not necessarily cause anisotropy in oxygen permeability and water conductivity though. 相似文献
110.
The underpotential deposition (UPD) of Cd on “real” and “quasi-ideal” silver single crystal surfaces of (111) and (100) crystallographic orientation as well as on polycrystalline silver substrate has been investigated in 0.5 M Na2SO4 supporting electrolyte solutions. At high underpotentials 100 < ΔE < 350 mV, the UPD is characterized by a quasi-reversible adsorption/desorption of Cd whereas at low underpotentials. ΔE < 50 mV, an increase of the anodic stripping charge with the polarization time is found due to the formation of an AgCd alloy at the substrate surface. The time dependence of this process can be described by a parabolic rate law, the rate constant of which is a function of ΔE and temperature T. Relatively low activation energies of about 70 kJmol?1 were determined from measurements at 293 ? T ? 338 K. The results are discussed in terms of a semi-infinite-linear diffusion model. The alloy formation process is assumed to be initiated by a place exchange between Ag substrate atoms and vacancy sites within a mobile Cd adsorbate layer thus forming the initial stage of a highly distorted AgCd alloy. The further growth will take place by the movement of Ag atoms through the vacancy-rich surface alloy and the simultaneous deposition of Cd at the interface AgCd/Cd2+. 相似文献