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11.
A blood-free medium for the recovery of thermophilic Campylobacter was compared with Butzler Medium Virion during a one-year study using 2,893 human feces samples. Ninety Campylobacter strains (3.1 %) were isolated after incubation for 48 h at 42 C in a candle jar atmosphere. Three strains of Campylobacter jejuni were isolated on the blood-free medium only and one on Butzler Medium Virion only. Fecal flora was equally well inhibited on both media except for gram-positive organisms, which were completely inhibited only on the blood-free medium.  相似文献   
12.
Artificially weathered crude oil was degraded by four diverse cultures of mixed marine bacteria under optimized conditions for 7 and 14 days. Loss in total weight of starting oil (30 g) ranged from 6.8–17.3% in biologically active incubations compared with only 0.9–1.1% in sterile and nutrient-limited controls. In all incubations, both neutral and acidic water-soluble fractions (WSF) were accumulated. In biologically active systems, 50.9–249.0 mg neutral and 63.3–406.8 mg acidic WSF were accumulated whereas only 6.5–11.1 mg neutral and 1.7–2.2 mg acidic WSF were accumulated in control incubations. Analysis by gas chromatography demonstrated that accumulated WSF in biologically active systems contained compounds different from those washed from the starting crude oil. Exposure of grass shrimp (Palaemonetes pugio) embryos to neutral WSF from each of the biologically active cultures resulted in high embryo mortalities relative to sterile and nutrient-limited controls which exhibited >90% hatching success and larval survival. Toxicity of neutral WSF was also demonstrated on larvae of mysids (Mysidopsis bahia). In both cases, toxicity occurred only on exposure to neutral material accumulated by active, oil-degrading cultures and not with material washed from the weathered crude oil. These results imply that unique compounds were accumulated during degradation that may have been responsible for increased toxicity. Received: 23 December 1997/Accepted: 27 July 1998  相似文献   
13.
Donnelly LF  Foss JN  Frush DP  Bisset GS 《Radiology》1999,210(2):493-497
PURPOSE: To (a) determine the appearances and timing of heterogeneous splenic enhancement at spiral computed tomography (CT) and (b) identify variables influencing heterogeneous splenic enhancement. MATERIALS AND METHODS: Sequential isolevel (24-mAs) CT images of the spleen obtained at 6-second intervals after initiation of contrast material injection in 112 children (mean age, 4.5 years) were reviewed. Heterogeneity characteristics assessed included type, onset, maximum, and resolution. Relationship to variables (injection rate, age, splenomegaly) was assessed with the Fisher exact test. RESULTS: Eighty-one of the 112 patients (72%) had transient heterogeneity: archiform (45 patients), diffuse (25 patients), and focal (11 patients). Mean times were as follows: initial visualization after onset of contrast material injection, 19.2 seconds; maximum heterogeneity, 27.3 seconds; and resolution, 47.4 seconds. Statistically significant relationships were seen between frequency of heterogeneity and injection rate (> or = 1 mL/sec, 82%; < 1 mL/sec, 50% [P = .001]), age (> 1 year, 76%; < or = 1 year, 46% [P = .04]), and splenomegaly (present, 20%; absent, 77% [P = .048]). CONCLUSION: Heterogeneous splenic contrast enhancement is common, has several patterns of appearance, and is predictably encountered during the 70 seconds after the initiation of contrast material injection. Injection rate, age, and presence of splenic disease influence the frequency with which these artifacts are encountered.  相似文献   
14.
Patient-based questionnaires were designed with the aim to identify and rank long-term somatic and psychosocial morbidity in patients with low-stage testicular cancer. A further intention was to compare patients' assessments with experienced doctors' general opinion on quality of life items in cured testicular cancer patients. In pilot study I, 103 tumour-free patients ranked items of physical and psychosocial morbidity after having had various kinds of treatment. Though the ranking procedure appeared to cause some difficulties amongst the patients and subsequently was abandoned, the results indicated considerable differences between the patients' and doctors' evaluations. In pilot study II patients were asked to score the different items. The questionnaire of pilot study II was completed by 107 patients from the Norwegian Radium Hospital (NRH) and 99 relapse-free patients from the Royal Marsden Hospital (RMH) with testicular cancer stage I at least 1 year after infradiaphragmatic radiotherapy (n = 94) or adjuvant chemotherapy (2 cycles,n=26), or patients who had been followed on the surveillance program (n = 86). A total of 93 doctors completed a similar questionnaire, thereby expressing their general opinion on long-term morbidity in comparable testicular cancer patients as seen during routine clinical follow-up. Both the irradiated patients and those on the surveillance program reported slight degrees of Raynaud-like phenomena, neurotoxicity and ototoxicity, most probably representing background morbidity in an age-matched general male population. Doctors tended to underestimate their patients' somatic morbidity, but often overestimated the degree of psychological distress, in particular in patients on the surveillance program. Significant differences between RMH and NRH patients with regard to sexual problems and to leisure time activity may be explained by cultural differences in the two countries. The items presented in the questionnaire used identify important issues for patients cured of testicular cancer which may be used in future multicentre trans-cultural studies assessing these patients' quality of life. This will provide sufficient data for psychometric testing and, together with the findings from patients' free comments, support the final design of a testicular cancer quality of life module.  相似文献   
15.
PURPOSE: Intestinal non-Hodgkin's lymphomas are not well characterized. We therefore studied prospectively their clinical features and response to standardized therapy. PATIENTS AND METHODS: Fifty-six patients with primary intestinal lymphoma were included in a prospective, nonrandomized multicenter study. Lymphoma resection was recommended and staging was performed according to the Ann Arbor classification. Patients were scheduled to receive six cycles of cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP) chemotherapy, and at stages EIII to EIV, they received additional involved-field radiotherapy. Corticosteroids were used in patients who could not receive chemotherapy. RESULTS: Thirty-five patients had intestinal T-cell lymphoma (ITCL), 21 patients had intestinal B-cell lymphoma (IBCL; 18 diffuse large-cell lymphomas, two marginal-cell lymphomas, and one follicle-center lymphoma). Thirty-four patients at stages EI to EII (14 ITCL and 20 IBCL) and nine patients at stages EIII to EIV (all ITCL) received chemotherapy. No patient in stages EIII to EIV received radiotherapy, because death occurred in 12 of 14 patients. Two-year cumulative survival in patients with IBCL was 94% (95% CI, 82% to 100%) and higher than in patients with ITCL (28% [95% CI, 13% to 43%]; P <.0001), even when only stages EI to EII were considered (ITCL, 37.5% [95% CI, 16.5% to 58.5%]; P <.0001). IBCL patients compared with ITCL patients were at lower lymphoma stages (P <.01), had higher Karnofsky status (P <.005), had intestinal perforation less often (P <.05), required emergency operation less often (P <.05), received CHOP (P <.05) more often, and reached complete remission (P <.0005) more frequently. CONCLUSION: IBCL patients at stages EI and EII respond well to chemotherapy, but the prognosis and treatment of ITCL patients is unsatisfactory.  相似文献   
16.
In this era of medical technology assessment and evidence-based medicine, evaluating new methods to measure physiologic variables is facilitated by standardization of reporting results. It has been proposed that assessing repeatability be followed by assessing agreement with an established technique. If the "limits of agreement" (mean bias +/- 2SD) are not clinically important, then one could use two measurements interchangeably. Generalizability to larger populations is facilitated by reporting confidence intervals. We identified 44 studies that compared methods of clinical measurement published during 1996 to 1998 in seven anesthesia journals. Although 42 of 44 (95.4%) used the limits of agreement methodology for analysis, several inadequacies and inconsistencies in reporting the results were noted. Limits of agreement were defined a priori in 7.1%, repeatability was evaluated in 21.4%, and relationship (pattern) between difference and average was evaluated in 7.1%. Only one of the articles reported confidence intervals. A computer macro for the Minitab statistical package (State College, PA) is described to facilitate reporting of Bland and Altman analysis with confidence intervals. We propose standardization of nomenclature in clinical measurement comparison studies. IMPLICATIONS: A literature review of anesthesia journals revealed several inadequacies and inconsistencies in statistical reports of results of comparison studies with regard to interchangeability of measurement methods. We encourage journal editors to evaluate submissions on this subject carefully to ensure that their readers can draw valid conclusions about the value of new technologies.  相似文献   
17.
PURPOSE: Prostate-specific membrane antigen (PSMA) is a cell surface protein that is overexpressed in prostate cancer, including hormone-refractory and metastatic disease. Our goal in this study was to develop a series of PSMA-based imaging agents for clinical use. EXPERIMENTAL DESIGN: We have synthesized and evaluated the in vivo biodistribution of two radiolabeled urea derivatives that have high affinity for PSMA in severe combined immunodeficient mice harboring MCF-7 (breast, PSMA-negative), PC-3 (prostate, PSMA-negative), and LNCaP (prostate, PSMA-positive) xenografts. Radiopharmaceutical binding selectivity and tumor uptake were also evaluated in vivo using dedicated small animal positron emission tomography, single photon emission computed tomography, and gamma scintigraphic imaging devices. N-[N-[(S)-1,3-dicarboxypropyl]carbamoyl]-S-[(11)C]methyl-L-cysteine ([(11)C]DCMC K(i), 3.1 nmol/L) and N-[N-[(S)-1,3-dicarboxypropyl]carbamoyl]-S-3-[(125)I]iodo-L-tyrosine ([(125)C]DCIT K(i), 1.5 nmol/L) were synthesized using [(11)C]CH(3)I and with [(125)I]NaI/Iodogen, respectively.RESULTS: At 30 minutes postinjection, [(11)C]DCMC and [(125)I]DCIT showed tumor/muscle ratios of 10.8 and 4.7, respectively, with clear delineation of LNCaP-derived tumors on imaging. MCF-7- and PC-3-derived tumors showed significantly less uptake of [(11)C]DCMC or [(125)I]DCIT. CONCLUSION: These results show the feasibility of imaging PSMA-positive prostate cancer using low molecular weight agents.  相似文献   
18.
19.
Intrathecal neostigmine and sufentanil for early labor analgesia.   总被引:18,自引:0,他引:18  
BACKGROUND: Recent efforts to improve the combined spinal epidural (CSE) technique have focused on adding opioids to other classes of analgesics. In this study, the authors used intrathecal neostigmine in combination with intrathecal sufentanil to investigate the usefulness of neostigmine for reducing side effects and prolonging the duration of sufentanil. METHODS: One hundred six healthy pregnant women in labor were enrolled in this study, which was divided into four phases. In all phases, patients received a CSE anesthetic while in the lateral position. In phase I, three groups of six women each received intrathecal neostigmine, 5, 10, or 20 microg, in an open-label, dose-escalating safety assessment. In phase II, 24 women received intrathecal sufentanil alone to establish an ED50 (dose that produces > 60 min of labor analgesia in 50% of patients). In phase III, an ED50 was established for sufentanil combined with a fixed dose of neostigmine (10 microg). In phase IV, 40 women received either twice the ED50 of sufentanil alone or twice the ED50 of sufentanil plus neostigmine, 10 microg. RESULTS: Neostigmine alone had no adverse effects on maternal vital signs, fetal heart rate, or Apgar scores. Neostigmine, 20 microg, produced analgesia in one patient and severe nausea and vomiting in another. The ED50 for intrathecal sufentanil alone was 4.1 +/- 0.31 microg, and the ED50 for intrathecal sufentanil combined with neostigmine, 10 microg, was 3.0 +/- 0.28 microg. The duration of analgesia and side effects from double these ED50s (sufentanil, 9 microg, or sufentanil, 6 microg, plus neostigmine, 10 microg) were similar between groups. CONCLUSIONS: The 10-microg intrathecal neostigmine dose alone produced no analgesia or side effects, but reduced the ED50 of intrathecal sufentanil by approximately 25%. Additionally, doses approximately double these ED50s each produced a similar duration of analgesia and side effects, indicating intrathecal neostigmine shifts the dose-response curve for intrathecal sufentanil to the left.  相似文献   
20.
There are strong indications that only a small fraction of grafts successfully engraft in clinical islet transplantation. One explanation may be the instant blood-mediated inflammatory reaction (IBMIR) elicited by tissue factor, which is produced by the endocrine cells. In the present study, we show that islets intended for islet transplantation produce tissue factor in both the transmembrane and the alternatively spliced form and that the membrane-bound form is released as microparticles often associated with both insulin and glucagon granules. A low-molecular mass factor VIIa (FVIIa) inhibitor that indirectly blocks both forms of tissue factor was shown in vitro to be a promising drug to eliminate the IBMIR. Thrombin-antithrombin complex (TAT) and FVIIa-antithrombin complex (FVIIa-AT) were measured in nine patients who together received 20 infusions of isolated human islets. Both the TAT and FVIIa-AT complexes increased rapidly within 15-60 min after infusion. When the initial TAT and FVIIa-AT levels were plotted against the increase in C-peptide concentration after 7 days, patients with an initially strong IBMIR showed no significant increase in insulin synthesis after 7 days. In conclusion, tissue factor present in both the islets and the culture medium and elicits IBMIR, which affects the function of the transplanted islets.  相似文献   
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