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1.
A D Deitch V A Andreotti M A Strand L Howell R W deVere White 《The Journal of urology》1990,143(4):700-705
We describe a method to fix exfoliated bladder cells that is suitable for followup of bladder cancer patients by deoxyribonucleic acid flow cytometry. After fixation with room temperature methanol plus acetic acid (20:1, volume:volume) urine and bladder washing samples from these patients can be stored at room temperature for 3 to 7 days and then assessed reliably for the presence of aneuploidy and the percentage of hyperdiploid cells. For those with active transitional cell carcinoma diagnostic accuracy comparing fresh to fixed specimens was improved from 58 to 92% with urine and from 50 to 100% with washing samples. For patients with a history of transitional cell carcinoma who currently are free of disease the false positive rate remains unchanged after fixation. The procedure described is suitable for use in the outpatient clinic and should permit shipping of samples without refrigeration to a central flow cytometry facility for analysis. 相似文献
2.
Summary DNA flow cytometry was used to examine the effects of five chemotherapeutic agents, vinblastine, cisplatinum, 5-fluorouracil, cyclophosphamide and Adriamycin, on mouse testes. Alterations in the haploid (1C), diploid (2C) and tetraploid (4C) cell compartments were assessed at 11, 29 and 56 days after giving mice a single intraperitoneal injection of each agent. Analysis of the histograms proved to be a rapid and reproducible method of monitoring injury in this animal model. Because this procedure can detect subtle testicular injuries, it is predicted that DNA histograms obtained from fine needle aspirates will gain increasing acceptance in the management of the oligo- and azoospermic patient. 相似文献
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INVOLVEMENT OF NON-NMDA AND NMDA RECEPTORS IN GLUTAMATE-INDUCED PRESSOR OR DEPRESSOR RESPONSES OF THE PONS AND MEDULLA 总被引:1,自引:0,他引:1
SY Chen WC Wu CJ Tseng JS Kuo CY Chai 《Clinical and experimental pharmacology & physiology》1997,24(1):46-56
1. Fifty-five intact and six baroreceptor denervated and vagotomized cats of either sex were anaesthetized intraperito-neally with urethane (400 mg/kg) and a-chloralose (40 mg/kg). Responses of the systemic arterial pressure (SAP), mean SAP (MSAP) and sympathetic vertebral nerve (VNA) and renal nerve activities (RNA) were recorded. 2. In intact animals, monosodium L-glutamate (Glu, 0.1 mol/L, 50 nL) was microinjected into pressor areas of the locus coeruleus (LC), gigantocellular tegmental field (GTF), rostral ventrolateral medulla (RVLM) and dorsomedial medulla (DM), and the depressor areas of caudal ventrolateral medulla (CVLM). The induced actions were compared before and after microinjection of either glutamate antagonists, glutamate diethylester (GDEE, 0.5 mol/L, 50–100nL), a competitive AMPA receptor blocker, or 2-amino-5-phosphonovaleric acid (D-AP5, 0.025 mol/L, 50–100 nL), a competitive N-methyl-D-aspartate (NMDA) receptor blocker. GDEE completely blocked the increases of SAP and VNA elicited from all pressor areas. D-AP5 only partially blocked the pressor but slightly blocked VNA and RNA responses from LC, GTF and DM, particularly those from RVLM. Neither GDEE nor D-AP5 blocked the depressor responses of SAP and two nerve activities elicited from CVLM. 3. In baroreceptor denervated animals, NMDA (2 mmol/L, 50–100 nL) and AMPA (0.2 mmol/L, 50–100 nL) were micro-injected into the same pressor areas of GTF, RVLM and DM and the depressor area of CVLM responsive to Glu activation (0.1 mol/L, 30 nL). In RVLM, DM and CVLM, the results of either NMDA or AMPA were similar to those induced by Glu. However, in GTF, microinjection of either NMDA or AMPA did not induce similar responses to Glu. This suggests that the nature of GTF may differ from RVLM and DM. 4. The above results suggest that the Glu-induced pressor responses from LC, GTF, DM and especially RVLM, are primarily mediated through AMPA receptors. The Glu-induced depressor responses from CVLM may not be predominantly mediated by either AMPA or NMDA receptors. 5. In both baroreceptor-intact and -denervated cats stimulation of the pressor areas often produced an increase of VNA and a decrease of RNA, while in the depressor CVLM decreased both VNA and RNA. The VNA, but not RNA were positively correlated with the pressor responses, while both VNA and RNA were positively correlated with the depressor responses. This may suggest that neurons of the sympathetic vertebral and renal nerves are topographically organized in the brain. 相似文献
5.
Hillmann JS; Mesgarzadeh M; Revesz G; Bonakdarpour A; Clancy M; Betz RR 《Radiology》1987,165(3):769-773
Proximal femoral focal deficiency, an uncommon congenital anomaly, necessitates early radiologic classification for surgical planning and treatment. Objective radiographic criteria, including femoral length index, acetabular depth index, acetabular angle index, and shape of the proximal femur were determined in 49 patients before cartilaginous ossification of the femoral capital epiphysis; final classification was based on follow-up radiographs or findings at arthrography or surgery. These parameters were analyzed to determine the accuracy and contributions of each in classification. Correct classification into one of three groups was possible in 86% of cases with use of three of the parameters: femoral length index, acetabular depth index, and shape of the proximal femur. The acetabular angle was found to contribute insignificantly to classification. Magnetic resonance imaging, used in only one case, depicted the nonossified cartilaginous femoral capital epiphysis, thus obviating the need for invasive diagnostic procedures and facilitating early classification. 相似文献
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Role of bacterial adherence and the mucus barrier on bacterial translocation: effects of protein malnutrition and endotoxin in rats. 总被引:7,自引:0,他引:7 下载免费PDF全文
OBJECTIVE: The purpose of the study was to investigate the potential relations between mucosal bacterial adherence, intestinal mucus and mucin content, and bacterial translocation. SUMMARY BACKGROUND DATA: The attachment of bacteria to mucosal surfaces is the initial event in the pathogenesis of most bacterial infections that originate at mucosal surfaces, such as the gut. The intestinal mucus layer appears to function as a defensive barrier limiting micro-organisms present in the intestinal lumen from colonizing enterocytes. Consequently, studies focusing on the biology of bacterial adherence to the intestinal mucosa likely are to be important in clarifying the pathogenesis of gut origin sepsis. METHODS: To explore the relations between intestinal bacterial adherence, mucus bacterial binding, and bacterial translocation, two models were used. One (protein malnutrition) in which profound alterations in intestinal morphology occurs in the absence of significant translocation and one (endotoxin challenge) in which bacterial translocation occurs and intestinal morphology is relatively normal. RESULTS: Protein malnutrition was not associated with bacterial translocation and measurement of enteroadherent, mucosally associated bacterial population levels documented that the total number of gram-negative enteric bacilli adherent to the ileum and cecum was less in the protein-malnourished rats than in the normally nourished animals (p < 0.01). Furthermore, there was an inverse relation between the duration of protein malnutrition and bacterial adherence to the intestinal mucosa (r = 0.62, p < 0.002). In contrast, after endotoxin challenge, the level of enteroadherent bacteria was increased and bacterial translocation was observed. The binding of Escherichia coli to immobilized ileal mucus in vitro was decreased significantly in protein-malnourished rats, whereas E. coli binding to insoluble ileal mucus was increased in the rats receiving endotoxin. CONCLUSIONS: This study indicates that the adherence of bacteria to the intestinal mucosal surface is an important factor in bacterial translocation, that intestinal mucus modulates bacterial adherence, and that increased levels of mucosally associated bacteria are associated with a loss intestinal barrier function to bacteria. 相似文献
8.
Serum ionic fluoride levels in haemodialysis and continuous ambulatory peritoneal dialysis patients 总被引:1,自引:1,他引:0
al-Wakeel JS; Mitwalli AH; Huraib S; al-Mohaya S; Abu-Aisha H; Chaudhary AR; al-Majed SA; Memon N 《Nephrology, dialysis, transplantation》1997,12(7):1420-1424
High serum fluoride (F-) in patients with chronic renal failure (CRF) and
end-stage renal disease (ESRD) is associated with risk of renal
osteodystrophy and other bone changes. This study was done to determine F-
in normal healthy controls and patients with ESRD on haemodialysis (HD) or
peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females)
and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in
the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l)
of F- content in drinking water. Control subjects showed a mean serum F-
concentration of 1.08 +/- 0.350 microM/l. Males in control group showed
slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than
females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F-
concentration did not correlate significantly with age and sex among
control subjects, whereas such correlation was observed in patients with
ESRD on dialysis. Mean serum F- concentration was significantly higher in
patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal
controls. When grouped according to sex, the mean serum F- concentration in
males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than
females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped
according to age, it was observed that F- concentration was significantly
higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with
age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated
with age and sex, being higher in males and above 20 years. Despite
appreciable clearance of F- (39-90%) across the peritoneum, patients on
CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs
2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their
serum F- concentration above 3.0 microM/l, posing the risk of renal
osteodystrophy.
相似文献
9.
Rupture of the distal biceps tendon: evaluation with MR imaging 总被引:2,自引:0,他引:2
10.