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91.
92.
Several factors promote the progression of renal disease, including glomerular hypertension and hypertrophy, molecular factors such as cytokines and growth hormones, proteinuria, acidosis, and hyperlipidemia. Regardless of the underlying etiology, many patients with chronic renal insufficiency will ultimately require kidney replacement therapy. Your goal is to delay the progression of renal failure, mainly through aggressive control of blood pressure. Other possible interventions include protein restriction, bicarbonate therapy, and lipid-lowering drugs.  相似文献   
93.
We have synthesized a new compound, 3-bromoacetylamino benzoylurea (3-BAABU), which showed strong cancericidal activity by inducing irreversible mitotic arrest and subsequently apoptosis in human T cell leukemic cells (CEM), human biphenotypic leukemic cells (SP), a human prostate cancer cell line (PC-3), murine melanoma cells (B-16), and murine lymphoma/leukemia cells (EL4) in vitro with an ID50 in the range of 0.013-0.07 microg/ml (0.04-0.22 microM). Treatment of tumor cells for 12-24 h with 3-BAABU resulted in mitotic arrest at prometaphase/metaphase/anaphase, with separation and dispersion of chromosomes and with the absence of mitotic spindle apparatus in cytoplasm. Treatment with 3-BAABU had no cytotoxic and mitotic blocking effect in normal human lymphocytes, proliferating fibroblast cells (3T3), or proliferating myocardial cells (MOT). Cell cycle analyses showed that most treated leukemic cells accumulated at M phase 12 h after treatment. By the end of 48 h of treatment, the cells underwent apoptosis with DNA fragmentation. 3-BAABU inhibited the assembly of microtubules from tubulin but did not interfere with the disassembly of microtubules. The presence and the position of bromine and urea groups on the benzoic ring are the determining factors for its inhibition of microtubule assembly. Replacing bromine with chlorine yielded much less mitotic blocking activity and increased the ID50 40-fold. Substitution of the urea group with ethyl ester abrogated the activity of blocking mitosis but induced apoptosis. Moving the bromoacetylamino group from the 3-position to the 4-position removed blocking activity for mitosis but induced necrosis. These results suggest that 3-BAABU possesses a unique and functional structure and is a potential agent for cancer chemotherapy.  相似文献   
94.
When assuming a species-typical tripodal posture, female Mongolian gerbils most often rest on their left forepaws and hold their right forelimbs aloft; male gerbils most often do the reverse. This experiment examined effects of gonadectomy, both in infancy and in adulthood, on the sexually dimorphic asymmetry in forelimb use by Mongolian gerbils when maintaining a tripodal stance. In adulthood, both male and female gerbils that had been gonadectomized at birth reversed their forelimb use while in a tripodal stance: Gonadectomized males used their forelimbs as did sham-operated females, and gonadectomized females used their forelimbs as did sham-operated males. Gonadectomy in adulthood abolished the sexual dimorphism in forelimb use seen in sham-operated subjects. It was concluded that gonadal hormones have organizational as well as possible activational effects on adult patterns of forelimb use by gerbils.  相似文献   
95.
Continuous assessment of cardiac output and SVO2 in the critically ill may be helpful in both the monitoring variations in the patient's cardiovascular state and in determining the efficacy of therapy. Commercially available continuous cardiac output (CCO) monitoring systems are based on the pulsed warm thermodilution technique. In vitro validation studies have demonstrated that this method provides higher accuracy and greater resistance to thermal noise than standard bolus thermodilution techniques. Numerous clinical studies comparing bolus with continuous thermodilution techniques have shown this technique similarly accurate to track each other and to have negligible bias between them. The comparison between continuous thermal and other cardiac output methods also demonstrates good precision of the continuous thermal technique. Accuracy of continuous oximetry monitoring using reflectance oximetry via fiberoptics has been assessed both in vitro and in vivo. Most of the studies testing agreement between continuous SVO2 measurements and pulmonary arterial blood samples measured by standard oximetry have shown good correlation. Continuous SVO2 monitoring is often used in the management of critically ill patients. The most recently designed pulmonary artery catheters are now able to simultaneously measure either SVO2 and CCO or SVO2 and right ventricular ejection fraction. This ability to view simultaneous trends of SVO2 and right ventricular performance parameters will probably allow the clinician to graphically see the impact of volume loading or inotropic therapy over time, as well as the influence of multiple factors, including right ventricular dysfunction, on SVO2. However, the cost-effectiveness of new pulmonary artery catheters application remains still questionable because no established utility or therapeutic guidelines are available.  相似文献   
96.
The thermodynamics of MnO-containing slags was reviewed, and the properties of such slags were correlated by application of the cell model. This model, together with a previously developed unified interaction parameter model for the metal phase, was used to simulate the gas-slag-metal conditions in the hearth of a ferromanganese submerged arc furnace. The calculated slag and metal compositions and distribution of Mn, Si, and K between slag, metal, and fume were compared with plant data and satisfactory agreement was obtained. A steady recirculation of potassium inside the furnace was also predicted. For a potassium percentage in the raw materials of 0.63 pct, the amount of the recirculating potassium was about 160 kg per metric ton of ferromanganese. Due to the recirculation, the average potassium content in the solid mix coming down to the hearth could be as high as 7 pct.  相似文献   
97.
Well-differentiated thyroid cancer (i.e. papillary microcarcinoma) may be revealed by a clinically palpable cervical node, especially in young patients. Primary tumor specificity (small-sized, superior location, invasion, multifocality) and characteristics of cervical node involvement (with synchronous central and lateral multiple node spread) require appropriate treatment by a skilled surgeon. Contrary to the primary tumor treatment (total thyroidectomy), surgical management of the cervical node basins remains controversial. Only a special knowledge of the specificity of this disease and cervical lymphatic anatomy will ensure a good prognosis for the patient.  相似文献   
98.
The magnetomechanical effect for a quenched and tempered alloy steel has been studied. In most published work it has been found that stress causes the magnetization to move toward the anhysteretic magnetization. However, in the present work it was found that under special conditions the magnetization moves away from the anhysteretic when a cyclic stress is applied. This behavior is tentatively explained by applying the Preisach model of ferromagnetic hysteresis  相似文献   
99.
100.
Medullary thyroid cancer is a tumor of the thyroid C cells that occurs in sporadic and hereditary clinical settings. Genetic testing of at-risk individuals is available and has been applied to patient management. Plasma calcitonin levels are a sensitive marker for the presence of disease. Surgery offers the best hope for cure and also is an effective modality for managing metastatic and recurrent disease.  相似文献   
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