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31.
PSA-based screening substantially increases the prostate cancer detection rate and the percentage of organ-confined tumors. It appears that there is some benefit from screening for prostate cancer because of the increased amount of potentially curable disease discovered and the fact that 96% of the pathologically staged tumors detected have histologic features associated with aggressive cancer. Additional evidence that nearly all tumors detected on the basis of initial PSA screening are apt to be clinically significant may be derived from the information that PSA-based screening decreases the incidence of incidental A1 grade III and A2 tumors but does not increase the detection of clinically insignificant A1 grade I and II tumors. At this time, PSA represents the most effective and valuable tool to detect early prostate cancer; therefore, PSA should be used to improve early diagnosis of prostate cancer. Some advances have been made with the introduction of age-specific reference ranges and the ability to measure free to total PSA ratios. The data presented support the clinical usefulness of age-specific reference ranges for serum PSA. Calculation of the free to total PSA ratio is valuable in deciding which screening volunteers require further evaluation, increases the specificity of PSA screening, and as demonstrated may be useful in deciding which patients with isolated PIN should undergo repeat biopsies. Based on these facts, PSA truly can be described as the most important and useful marker for adenocarcinoma of the prostate. Based on these encouraging results and the obligingness of the social insurances, we will be able to continue PSA screening for early detection of prostate cancer for all concerned Tyrolean men in the future. 相似文献
32.
JJ Worthington MH Pollack MW Otto RY McLean G Moroz JF Rosenbaum 《Canadian Metallurgical Quarterly》1998,34(2):199-205
OBJECTIVE: To assess the effect of the relief of obstruction on the ultimate function of the affected renal unit in urinary tuberculosis, and to identify predictors of functional recoverability. PATIENTS AND METHODS: Of a total of 82 patients with urinary tuberculosis presenting over 7 years, 38 with evidence of upper tract obstruction were analysed. All patients were assessed with pre-operative excretory urography, urinary mycobacterial cultures and serum chemistry. Patients with subnormally functioning kidneys were assessed with baseline renal scans. Preliminary intervention in the form of JJ stenting or percutaneous nephrostomy (PCN) was carried out in patients with reasonable renal function. Function was reassessed after 4 weeks to detect evidence of improvement and factors which could affect the outcome were determined. RESULTS: Thirty-eight patients had documented upper tract obstruction, of whom six had bilateral obstruction (total of 44 renal units). Ten renal units were not functioning at presentation, with a mean (SD) glomerular filtration rate (GFR) of 3.0 (5.73) mL/min, and no preliminary intervention was performed. In the remaining 34, preliminary intervention was carried out before definitive surgery (JJ stenting in 14, PCN in 15 and PCN followed by antegrade JJ stenting in five); 21 of these renal units were salvaged but 13 were lost despite overcoming the obstruction. Three of the 13 units deteriorated from having acceptable pre-treatment GFRs to becoming non-functional. Good renal cortical thickness, a low grade of renal involvement (Semb 1 or 2), the presence of more distal disease in the form of ureteric stricture and a GFR of > 15 mL/min were good predictors of renal recovery after diversion. CONCLUSIONS: The loss of some renal units seems inevitable in patients with urinary tuberculosis, despite advances in chemotherapy. Having pre-operative predictors of renal recovery may ensure optimal patient selection, thereby reducing the number of procedures and economic burden on the patient who does not require intervention. 相似文献
33.
Antiserum to leucokinin I, a neuropeptide originally isolated from the cockroach Leucophaea maderae, was used for immunocytochemical labeling of neurons in the brain and ventral ganglia of the moth Spodoptera litura during postembryonic development. In the ventral ganglia, leucokinin-like immunoreactivity begins to occur in the abdominal ganglion A3 to A7 of first instar larva. One to two weakly labeled pairs of bilateral LK-LI cell bodies are located in the subesophageal ganglion of fourth to sixth instar larvae and in the abdominal ganglia A1 to A7 of second to sixth instar larvae. The abdominal ganglion A1 of fourth to sixth instar larvae and A8 of sixth instar larva each contain one weakly labeled pair of median LK-LI cell bodies. Two strongly labeled pairs of bilateral LK-LI neurons are found in A3 to A7 of third to sixth instar larvae. Abdominal ganglia A1 to A8 of prepupa, pupa and adult contain one to three weakly labeled pairs of bilateral LK-LI neurons. Two strongly labeled pairs of bilateral LK-LI neurons in each of the abdominal ganglia of larva, prepupa, pupa and adult send axons to the neuropil, and then each axon bifurcates into two axonal branches. Theses axonal branches from two bundles. From each of the two pairs of neurons an axon exits through the posterior ventral nerve (N2) which runs to the transverse nerve of the next posterior segment. In larval brains, 2-16 pairs of bilateral LK-LI cell bodies can be found together with LK-LI processes in the central neuropil. The larval brains show large changes in the number of LK-LI neurons throughout postembryonic development. The number of LK-LI cell bodies are reduced in number from sixth instar larval brain. Therefore, prepupal, pupal and adult brains contain a smaller number of LK-LI cell bodies. Two pairs of LK-LI median neurosecretory cells located immediately beside the pars intercerebralis in larval brains increase to three pairs in the 7-day-old pupal brain. In the adult, however, LK-LI median neurosecretory cells decrease to one pair. 相似文献
34.
TC Hsu Y Zhao RY Wang R Dickerson JC Liang X Wang Y Wu 《Canadian Metallurgical Quarterly》1998,12(3):617-620
In a breast cancer cell line, MDA-MB-468, established in our laboratory, an average of 3% of the mitotic cells exhibited a phenomenon known as centromere splaying, which is a characteristic feature of cells of patients with Roberts syndrome. However, centromere splaying in cells of Roberts syndrome patients is limited to i) the centromere region and ii) chromosomes with large amounts of heterochromatin. When the breast cancer cells were treated with an extract of green tea GTE-TP91, up to 45% of the metaphases were observed to exhibit this behavior; and the precocious centromere separation was highly exaggerated, affecting all chromosomes in such metaphases. Apparently, as the sister centromeres continued to pull apart, they carried the chromatids with them, except for the telomere regions, giving a ring-like configuration. Eventually, the sister chromatids became completely separated. Whether this bizarre phenomenon was induced by the polyphenols contained in this green tea extract GTE-TP91 is not known, but this phenomenon, upon further investigation, may throw some light on chromosomal proteins, centromere behavior, telomere behavior and related questions. 相似文献
35.
RY Litovsky 《Canadian Metallurgical Quarterly》1997,102(3):1739-1745
The precedence effect refers to an auditory phenomenon which occurs when two similar sounds are presented from different locations with a brief delay, and only one sound is heard whose perceived location is dominated by the first source. Although the lagging source si not localized as an independent event, under some conditions, adults are able to extract its directional cues. Developmental studies suggest that this ability changes during the development. However, those studies have used stimulus configurations which minimize the measurement of that ability. In the present study adults were first tested under several conditions, and the one which produced optimal performance was chosen for testing children. Using the minimum audible angle (MAA) task in the azimuthal plane, performance was compared for a single-source condition and two precedence conditions: in lag discrimination the lagging source changed location while the lead remained at midline, and in lead discrimination the reverse occurred. Subjects were 18 months old, 5 years old, and adult. Significant improvements in MAA occurred with an increase in age, especially in the precedence conditions. Within each group, performance was significantly better in single-source condition, followed by the lead and the lag discrimination. 相似文献
36.
Dual control of heat shock response: involvement of a constitutive heat shock element-binding factor
Heat shock factor (HSF) has been implicated as the key regulatory protein in the heat shock response. Our studies on the response of rodent cells to heat shock or sodium arsenite indicate that a high level of HSF-DNA-binding activity, by itself, is not sufficient for the induction of hsp70 mRNA synthesis; furthermore, a high level of HSF binding is also not necessary for this induction. Analysis of the binding of protein factors to the heat shock element (HSE) in extracts of stressed rodent cells indicates that the regulation of heat shock response involves the heat-inducible HSF and a constitutive HSE-binding factor. Our results also suggest that overexpression of human hsp70 may decrease the level of heat-induced HSF-HSE-binding activity in rat cells. 相似文献
37.
OBJECTIVE: To investigate the rheologic changes and circulatory abnormalities at the microvascular level during severe sepsis. DESIGN: Prospective, controlled trial. SETTING: Medical and surgical intensive care units of a university-affiliated hospital. PATIENTS: Nine normal controls and eight adult patients with severe sepsis who met the study entrance criteria. INTERVENTIONS: Forearm blood flow was measured at rest and during reactive hyperemia by air plethysmography. Simultaneous hemodynamic measurements and blood samples for rheologic measurements were taken. MEASUREMENTS AND MAIN RESULTS: Red blood cell deformability index was determined using a simple filtration procedure. Leukocyte aggregation in whole human blood was detected by using a leukergy test. Expression of the neutrophil adhesion molecule CD11b/CD18 was measured using a monoclonal antibody and flow cytometry. All data were taken within 24 hrs of the patient meeting criteria for entrance into the study. Cardiac output, oxygen delivery, and oxygen consumption measurements were consistent with the hyperdynamic phase of severe sepsis. Forearm blood flow was significantly (p < .05) greater in septic patients (21 +/- 3 mL/min) than in controls (12 +/- 2 to 36 +/- 5 mL/min (p < .05), while in the septic patients, forearm blood flow during reactive hyperemia increased from 21 +/- 3 to 32 +/- 4 mL/min. The ratio of forearm blood flow during reactive hyperemia to forearm blood flow at rest was 3.2 +/- 0.1 in the controls and 1.6 +/- 0.1 in the septic patients (p < .01). The red blood cell deformability index in whole blood was significantly (p < .01) decreased in the septic patients compared with the control subjects (0.41 +/- 0.07 vs. 0.98 +/- 0.08 mL/min). This difference remained true when the hematocrit was adjusted to 45% (0.82 +/- 0.06 vs. 1.04 +/- 0.06 mL/min; p < .05). Increased expression of the neutrophil adhesion molecule CD11b/CD18 was observed in septic patients (349 +/- 46 logarithmic fluorescence units) as compared with control subjects (233 +/- 26 logarithmic fluorescence units; p < .05). Leukergy was also significantly (p < .05) increased in septic patients (17.7 +/- 3.8%) as compared with control subjects (8.9 +/- 1.6%). A significant correlation was observed between leukergy and the expression of the neutrophil adhesion molecule CD11b/CD18 in controls and septic patients (r2 = .62; p < .01). Leukergy was also inversely correlated with whole blood red blood cell deformability index (r2 = .28; p < .05). CONCLUSIONS: Reactive hyperemia in the forearm is significantly diminished in patients with sepsis, suggesting impaired microvascular blood flow. Rheologic changes, including impaired red blood cell deformability, increased leukocyte aggregation, and endothelial adherence, may contribute to this abnormality by compromising effective capillary cross-sectional area. 相似文献
38.
39.
Embryoscopic diagnosis of conjoined twins presenting with a missed abortion has never been reported. The morphological and pathological examinations, and the exact time of death in the conceptus of a missed abortion are seldom clearly delineated. The newly developed field of embryoscopy has created a new frontier in early embryonic/fetal visualization and is able to confirm the sonographic diagnosis. In this report, we used a transcervical endoscope to verify conjoined twins (thoraco-omphalopagus) in a 10-week missed abortion. Based on the size and the external features of the dead embryo, which exhibited developmental arrest at nine weeks and three days of menstrual age, we estimated that the embryo had died four days before examination. The whole procedure proceeded smoothly without any immediate complications. 相似文献
40.
Recombinant proteins containing four cysteines at the i, i + 1, i + 4, and i + 5 positions of an alpha helix were fluorescently labeled in living cells by extracellular administration of 4',5'-bis(1,3, 2-dithioarsolan-2-yl)fluorescein. This designed small ligand is membrane-permeant and nonfluorescent until it binds with high affinity and specificity to the tetracysteine domain. Such in situ labeling adds much less mass than does green fluorescent protein and offers greater versatility in attachment sites as well as potential spectroscopic and chemical properties. This system provides a recipe for slightly modifying a target protein so that it can be singled out from the many other proteins inside live cells and fluorescently stained by small nonfluorescent dye molecules added from outside the cells. 相似文献