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101.
Association of the plasmid-mediated quinolone resistance determinant QnrA and the bla(VEB-1) gene was identified in a single Enterobacter cloacae isolate from K.-Bicêtre, France, and in 11 out of 23 bla(VEB-1)-positive enterobacterial isolates from Bangkok, Thailand. This result may explain in part the association between quinolone and extended-spectrum beta-lactam resistance.  相似文献   
102.
OBJECTIVE: To discern the mode of interleukin-1 (IL-1) inhibition of soluble IL-1 receptor accessory protein (sIL-1RAcP) by comparison with IL-1 receptor antagonist (IL-1Ra) in arthritis. METHODS: Adenoviral vectors encoding either sIL-1RAcP or IL-1Ra were administered systemically before onset of collagen-induced arthritis in DBA/1 mice. Anti-bovine type II collagen IgG and IL-6 were quantified in serum. Proliferative response of splenic T cells was determined in the presence of sIL-1RAcP or IL-1Ra. The effect on IL-1 inhibition of recombinant sIL-1RAcP and IL-1Ra was further examined in vitro, using NF-kappaB luciferase reporter cell lines. Quantitative polymerase chain reaction was used to determine the relative messenger RNA expression of the IL-1 receptors. RESULTS: Adenoviral overexpression of both sIL-1RAcP and IL-1Ra resulted in amelioration of the collagen-induced arthritis. Both IL-1 antagonists reduced the circulating levels of antigen-specific IgG2a antibodies, but only IL-1Ra was able to inhibit lymphocyte proliferation. By using purified lymphocyte populations derived from NF-kappaB reporter mice, we showed that sIL-1RAcP inhibits IL-1-induced NF-kappaB activity in B cells but not T cells, whereas IL-1Ra inhibited IL-1 on both cell types. A study in a panel of NF-kappaB luciferase reporter cells showed that the sIL-1RAcP inhibits IL-1 signaling on cells expressing either low levels of membrane IL-1RAcP or high levels of IL-1RII. CONCLUSION: We show that the sIL-1RAcP ameliorated experimental arthritis without affecting T cell immunity, in contrast to IL-1Ra. Our results provide data in support of receptor competition by sIL-1RAcP as an explanation for the different mode of IL-1 antagonism in comparison with IL-1Ra.  相似文献   
103.
[14C]AZQ (2–4 mg/m2, 100–200 mCi) was administered at varying times to five patients undergoing surgical resection of intracerebral tumors. Plasma, cerebrospinal fluid (CSF), edematous brain, and tumor specimens were obtained during surgery and the concentration of AZQ was determined radiochemically and chromatographically. Total [14C]AZQ equivalent concentration in tumor for two patients was determined to be 47.5% and 85% of concurrent plasma concentration which was similar to that found in normal brain (60.4% and 75.5% respectively). Only 18–45% of the total radioactivity in tumor tissue and 30–56% in plasma were accounted for by unchanged AZQ. These findings suggest that AZQ may be metabolized to a certain extent. Tissue samples from various organs were obtained during autopsy in a patient who expired ten days after AZQ administration. The highest AZQ concentration was found in the liver, followed by the kidney. Comparable amounts were found in normal brain and brain tumor (22 ng/ g vs. 31 ng/ g respectively). These results indicate that AZQ penetrates readily into the normal brain and brain tumor with a tendency to persist.  相似文献   
104.
Summary A high-pressure liquid chromatographic method was utilized to determine the concentration of the antileukemic agent methylgloxal bis(guanylhydrazone) (MGBG, NSC-32946) in tissue samples obtained at autopsy from patients who received MGBG. In a patient with cholangiocarcinoma who received one course of MGBG (500 mg/m2), the highest drug concentration was found in normal liver tissue. However, the drug concentration in intrahepatic tumor tissue was only 10% of that found in uninvolved liver. In a patient with acute myelogenous leukemia (AML) who received 12 courses of MGBG therapy, highly infiltrated lymph node tissue was found to contain the highest concentration of MGBG. High concentrations of the drug were also found in liver, spleen, kidney, adrenal, and thyroid. The drug penetrated well into normal brain tissue. After repeated administration, high drug concentrations were found in cerebral and cerebellar gray matter. These studies suggest that there is no selective uptake of MGBG into solid tumors early after drug administration and provide a pharmacologic rationale for testing this agent against endocrine and intracerebral tumors in man.The abbreviations used in this paper are MGBG methylglyoxal bis(guanylhydrazone) - TCA trichloroacetic acid - PCA perchloric acid - KOH potassium hydroxide - HPLC high-pressure liquid chromatography  相似文献   
105.
AIMS: The ductal plate abnormality of the liver in fetuses with the Meckel-Gruber syndrome has been well characterised, but its aetiology remains unknown. We have analysed liver structure in six fetuses with this syndrome, using routine histology, immunocytochemistry, and electron microscopy. METHODS: Liver tissue from six fetuses of 11-27 weeks gestational age was examined by immunoperoxidase staining with antigens to cyokeratin (AE1/3) and polyclonal CEA. We also examined the ultrastructure of the syndromic fetal liver. The findings were compared with livers of control fetuses obtained from miscarriages, of similar size and gestational age but without dysmorphic features or developmental anomalies. RESULTS: The ductal plate abnormality was present in all the fetuses with the Meckel-Gruber syndrome. There were abnormalities of biliary excretion in all syndromic fetuses. Ultrastructural studies of the portal tract revealed abnormal collagen bundles in the Meckel-Gruber syndrome. CONCLUSIONS: Our findings, in conjunction with other reports in the literature, suggest that the ductal plate abnormality may be caused by failure of anastomosis of the intra- and extrahepatic biliary systems, perhaps in association with abnormalities of the portal tract stroma and biliary excretion.  相似文献   
106.
OBJECTIVE: To assess the effect of short-term use of a gonadotropin releasing hormone (GnRH) analogue for 3 months before ovarian stimulation in patients with stage III and IV endometriosis after conservative surgery. STUDY DESIGN: Eleven patients were randomly selected to receive intramuscular injections of GnRH analogue, leuprolide acetate (3.75 mg), every 28 days, or 400 mg danazol orally 2 times per day for 3 months before ovarian stimulation after conservative laparoscopic or laparotomy surgeryfor stage III and IV symptomatic endometriosis (group 1), as compared with 30 patients who had received no postoperative treatment with GnRH analogue or danazol but underwent ovarian stimulation immediately after thefirst menses within 3 months postoperatively (group 2). RESULTS: Although the number of oocytes retrieved and number of embryos per cycle were significantly higher in group 1, the pregnancy rate per cycle in group 1 was not significantly different from that in group 2 (18% vs. 20%). The cumulative pregnancy rate at 12 months was 54.5% and 56.7% in group 1 and group 2, respectively. With regard to recurrence of disease after 24 months of follow-up, group 2 had a statistically significantly higher recurrence rate (13.3%) than did group 1 (0%). CONCLUSION: Short-term use of GnRH analogue before ovarian stimulation in women with stage III or IV endometriosis confers no definite benefits on pregnancy rates per cycle when compared with patients who received ovarian stimulation within 3 months after conservative surgery.  相似文献   
107.
OBJECTIVE: To assess the ecological validity of walking speed measurement after traumatic brain injury (TBI). PARTICIPANTS: Ten people with TBI who could walk independently and were participating in a rehabilitation program. DESIGN: Walking speed on 3 clinical gait tests (comfortable and fast pace over a 10-m distance and a 6-minute walk test) in 3 "natural" environments (a corridor in a brain injury rehabilitation unit, a car park of a metropolitan shopping center, and inside a metropolitan shopping center). Normative data were collected for 275 able-bodied pedestrians as they walked in the 3 natural environments. RESULTS: For subjects with TBI, agreement between the speeds used in the clinical gait tests and the natural environments was poor (intraclass correlation coefficient [ICC] values ranged from -0.24 to 0.63). The closest speed match was the comfortable paced 10-m walk test and walking in a corridor of a brain injury rehabilitation unit (ICC 0.63). Able-bodied pedestrians walked at significantly faster speeds than did subjects with TBI in all 3 natural environments. CONCLUSIONS: Comfortable walking speed appears to have the highest ecological validity of the clinical gait tests investigated. Practice in natural and more complex environments should be incorporated into walking rehabilitation programs for people with TBI.  相似文献   
108.
109.
We report on a novel procedure for invasive volumetric blood flow measurements using a commercially available Doppler flow wire system, which could, until now, only measure flow velocity. We here describe a method applicable in vivo to generate both velocity and cross-sectional area information from the same pulsed-wave Doppler signal for volumetric flow assessment. We demonstrate its feasibility and validation in vivo in pig coronary arteries. Our Doppler-derived volumetric flow measurements were compared with the respective transit-time flow and showed an excellent correlation (r = 0.969; p < 0.0001). Agreement between transit-time and Doppler-derived flow measurements could be observed for flow conditions ranging from 30 to 180 mL/min. The mean values for the two methods were 71.4 +/- 43.7 mL/min and 71.3 +/- 42.2 mL/min, respectively. We conclude that this technique might possibly be introduced into future clinical practice as an invasive procedure of choice for the assessment of volumetric blood flow.  相似文献   
110.
OBJECTIVE: To determine in patients with mammary carcinoma and a sentinel node metastasis whether pathological parameters of the sentinel node metastasis and the primary tumour might have predictive value with respect to the presence of metastases in other axillary nodes. DESIGN: Prospective. METHOD: The study group consisted of the first 100 consecutive patients with a sentinel node metastasis, who subsequently underwent a complete axillary dissection. The patients with metastases in the non-sentinel nodes were compared to those without such metastases regarding the size of the largest sentinel node metastasis and the presence of extranodal tissue invasion near any such node, and size, and type of the primary tumour. RESULTS: The median size of the metastases in the sentinel lymph node in the two groups was 3 mm versus 13 mm respectively (p < 0.001) and the frequency of extranodal tissue invasion 3% versus 74% respectively (p < 0.001); the combination of these factors strongly predicted the presence of non-sentinel lymph node metastases in the axilla (94% area under the receiver operating characteristics curve). None of the 30 patients with a micrometastasis < or = 2.0 mm in the sentinel lymph node had metastases in the non-sentinel axillary lymph nodes. Metastases were present in the non-sentinel axillary lymph nodes in 29 of the 31 patients with extranodal tissue invasion near the sentinel node. CONCLUSION: In breast cancer patients with a sentinel lymph node metastasis < or = 2.0 mm and without extranodal tumour growth a complete axillary lymph node dissection might be unnecessary as the risk of additional metastases was very small.  相似文献   
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