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We report a case of primary gastric choriocarcinoma with liver metastasis. The mixed histologic patterns included adenocarcinoma, undifferentiated carcinoma, and choriocarcinoma. Immunohistologic staining for the beta-subunit of human chorionic gonadotrophin (beta-HCG) showed positive results in the choriocarcinoma, adenocarcinoma, and normal mucosal gland. However, positive HCG cells were present at different intensities in the choriocarcinoma, adenocarcinoma, and normal mucosal gland. The level of HCG was significantly increased in serum. This unusual tumor probably resulted from dedifferentiation of a primary adenocarcinoma or developed directly from the mucosal glands.  相似文献   
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To facilitate effective management of pain and anxiety, and to permit more objective assessment of changes in this management, a pain and anxiety guideline was developed and has been followed uniformly for 3 years. The guideline describes four patient care categories: (1) ventilated acute, (2) nonventilated acute, (3) chronic acute, and (4) reconstructive. A small and consistent formulary was emphasized. A specific guideline for background, procedural, and transition pain and anxiety management was developed for each patient care category. All pain and anxiety medications given to all acutely burned children admitted to the Institute for 12 consecutive months were recorded, and daily pain and anxiety discomfort scores were noted using a 5-level action-based bedside scoring system. Doses of individual pain and anxiety medications were calculated as mg per kg per patient-day in each category, and all doses were found to be within guideline specifications. The efficacy of the guideline was judged by four discomfort scores: (1) background pain, (2) procedural pain, (3) background anxiety, and (4) procedural anxiety, and were adequate in all patient categories. There were no complications related to overmedication experienced during the interval. Our objective was to develop a guideline for pain and anxiety management that: (1) was safe and effective over a broad range of ages and injury acuities seen in the unit, (2) was explicit in its recommendations, (3) had a limited formulary to optimize staff familiarity with agents used, and (4) took advantage of the presence of a bedside nurse to continuously evaluate efficacy and intervene when needed through dose-ranging. Although many drugs are appropriate, our choices were based on institutional familiarity and simplicity. This process of developing a clear and consistent guideline can be duplicated in any unit.  相似文献   
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Salvage of lower-extremity Gustilo type IIIC fractures is difficult, time-consuming for the patients and physicians, and not universally successful because of poor functional outcomes. Even if successful with limb salvage, the functional result may be unsatisfactory because of mutilating injuries to muscle and nerve, bone loss, and the presence of chronic infection. From July 1991 until July 1994, revascularizations of open IIIC fractures were attempted for wounds with Mangled Extremity Severity Score (MESS) < or = 10. The functional results were evaluated at 2 years after injury. Thirty-six lower-extremity revascularizations were performed on 34 patients, including 1 patient with bilateral distal tibial IIIC fractures and a child with IIIC femoral fracture accompanied by ipsilateral distal tibial amputation. Excluded were patients with below-ankle IIIC fractures as well as patients who underwent immediate amputation at admission. After the revascularization, seven patients with IIIC fractures (7 of 36, 19.4%) underwent secondary amputation within 1 week. At the 2-year follow-up, the overall secondary amputation rate was 25% (9 of 36) and the salvage rate was 75% (27 of 36). Those were no deaths. Of the 29 salvaged limbs among these 27 patients, 23 limbs (23 of 29, 79.3%) required secondary coverage procedures that included 12 free flap transfers (12 of 29, 41.4%). Every patient needed subsequent reconstructive surgery to achieve an acceptable functional result. In this series, MESS was able to predict the secondary amputation rate and the functional result. Sixteen of the 17 limb-salvaged patients with MESS < or = 7 were able to achieve minimal functional requirements, whereas 3 of the 10 patients with MESS = 8 to 10 failed to achieve minimal functional requirements at the 2-year follow-up. Using statistical analysis, we found that the salvaged limbs with MESS < or = 9 exhibited a significant difference in achieving adequate function compared with limbs with MESS > 9. Using our protocol for treatment for IIIC fractures, the threshold for immediate amputation can be raised from MESS = 7 to MESS = 9. Our conclusions are (1) more severely injured limbs have poor functional results, (2) every patient needs subsequent reconstructive surgery, and (3) the MESS may be helpful in decision-making.  相似文献   
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DNA replication origins in chromosomes of eukaryotes are activated according to a temporal program. In the yeast Saccharomyces cerevisiae, activation of origins in early S phase appears to be a default state. However, cis-acting elements such as telomeres can delay origin activation until late S phase. Site-specific recombination was used to separate origin from telomere in vivo, thereby demonstrating that the signal for late activation is established between mitosis and START in the subsequent G1 phase. Once set, the signal can persist through the next S phase in the absence of the telomere. Establishment of the temporal program and of initiation competence of origins may be coincident events.  相似文献   
99.
The surface oxygen content of selected wood‐based phosphoric acid‐activated carbons was quantified using X‐ray photoelectron spectroscopy (XPS) and correlated with the residual bulk phosphate levels of the carbons and their adsorptivity in solution. The adsorption of Al3+, Cu2+, and para‐chlorophenol, respectively, from water decreased as a function of increasing surface oxygen content of the carbons. When the carbon of lowest surface oxygen content was oxidized with ozone to impart a surface oxygen content comparable to that of a carbon with a much higher phosphate level, adsorption of Al3+, Cu2+, and para‐chlorophenol from water decreased proportionally. The increase in polarity of the carbon surface was accompanied by a decrease in pH and appeared to be the dominant factor with respect to the adsorption of the target species from water. Copyright © 2005 Society of Chemical Industry  相似文献   
100.
During dynamic exercise in warm environments, requisite increases in skin and active muscle blood flows are supported by increasing cardiac output (Qc) and redistributing flow away from splanchnic and renal circulations. To examine the effect of age on these responses, six young (Y; 26 +/- 2 yr) and six older (O; 64 +/- 2 yr) men performed upright cycle exercise at 35 and 60% of peak O2 consumption (VO2peak) in 22 and 36 degrees C environments. To further isolate age, the two age groups were closely matched for VO2peak, weight, surface area, and body composition. Measurements included heart rate, Qc (CO2 rebreathing), skin blood flow (from increases in forearm blood flow (venous occlusion plethysmography), splanchnic blood flow (indocyanine green dilution), renal blood flow (p-amino-hippurate clearance), and plasma norepinephrine concentration. There were no significant age differences in Qc; however, in both environments the O group maintained Qc at a higher stroke volume and lower heart rate. At 60% VO2peak, forearm blood flow was significantly lower in the O subjects in each environment. Splanchnic blood flow fell (by 12-14% in both groups) at the lower intensity, then decreased to a greater extent at 60% VO2peak in Y than in O subjects (e.g., -45 +/- 2 vs. -33 +/- 3% for the hot environment, P < 0.01). Renal blood flow was lower at rest in the O group, remained relatively constant at 35% VO2peak, then decreased by 20-25% in both groups at 60% VO2peak. At 60% VO2peak, 27 and 37% more total blood flow was redistributed away from these two circulations in the Y than in the O group at 22 and 36 degrees, respectively. It was concluded that the greater increase in skin blood flow in Y subjects is partially supported by a greater redistribution of blood flow away from splanchnic and renal vascular beds.  相似文献   
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