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1.
For the past 10 to 15 years, radiation therapy and chemotherapy have played an increasingly important role in the treatment of various gastrointestinal malignancies, most prominently in anal and rectal cancer. Critical issues in the care of patients with anal and rectal cancer include not only local control and survival but organ preservation as well. For patients with carcinoma of the anal canal, external-beam irradiation with 5-fluorouracil and chemotherapy with mitomycin C have replaced surgery as primary therapy. Current studies are optimizing this therapy. In contrast, the management of distal rectal cancer is in evolution. Although the abdominoperineal resection has been long regarded as the definitive treatment of distal rectal cancer, it is associated with substantial morbidity (loss of anorectal function with a permanent colostomy and a high incidence of sexual and genitourinary dysfunction). As an alternative, treatment programs utilizing sphincter-preserving procedures with radiation therapy and chemotherapy are under active investigation. In selected patients, these strategies appear promising, and there have been reports of satisfactory local control and survival, as well as preservation of sphincter integrity.  相似文献   
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In a 63-year-old woman with longstanding type I diabetes mellitus, CAD and chronic heart failure, a subacute myocardial infarction developed, together with decompensation of cardiac function and diabetes and concurrent pneumonia. Acute heart failure with acute renal failure on top of diabetic nephropathy, and interstitial pulmonary edema was initially treated with hemofiltration and catechol amines together with antibiotic and perfusor-regulated insulin therapy, and systemic heparinization. Subsequent chronic treatment with digitalis, acetyl salicylic acid, insulin and a combination of an ACE inhibitor and a loop diuretic resulted in an improvement of heart failure to NYHA functional class II where PTCA of coronary multi-vessel disease could be performed with low risk.  相似文献   
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Infective endocarditis in heroin addicts has been reported to have a mortality as high as 85% and reports have varied widely regarding predominant valvular involvement and infecting microorganisms. A retrspective study was done and 61 cases of heroin-associated infective endocarditis were identified at Freedmen's Hospital and the District of Columbia General Hospital, Washington, DC between January 1969 and January 1973. Our results indicate that staphylococcal infection of the tricuspid valve has a much higher incidence in this population than has generally been believed and that it is the predominant presentation of infective endocarditis in these patients. The outcome of patients in our series compares favorably with previous reports and suggests that early diagnosis and prompt institution of appropriate antimicrobial therapy are important and may lead to improved survival in addicts with tricuspid endocarditis.  相似文献   
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The posterior wall of the central sulcus in forelimb area of SI has been expolred with extracellular micro-electrodes in baboons lightyl anaesthetized with nitrous oxide and sodium thiopentone. 2. The excitatory responses of 130 single units to low intensity electrical stimulation of the deep radial (muscle) and the superficial radial (cutaneous) nerves have been investigated. 3. Units that responded only to muscle nerve stimulation were located in area 3a but overlapped into area 3b. Units that responded only to cutaneous nerve stimulation were found mainly in area 3b but a number occurred in area 3a. Units that responded to both muscle and nerve stimuli (convergent units) were found throughout area 3a and the rostral part of area 3b. 4. Latency analyses of all three response groups revealed a single population of units responding to low threshold muscle nerve stimulation (mean latency 8.5 msec), and both early and late populations responding to low threshold cutaneous nerve stimulation (mean latencies 9.5 and 13.6 msec respectively). A number of the convergent units had very similar latencies for both inputs. 5. Electrical stimulation within area 3a deminstrated a projection from areas 1 and 3b to area 3a; such a pathway may provide a route for excitation of the late skin population which was found mainly in area 3a. 6. In area 3a units commonly responded to light touch, local pressure or deep pressure but only rarely to movement of hairs. A number of the convergent units responded to natural stimulation of cutaneous receptors.  相似文献   
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Eighty-four geriatirc ward patients were randomly assigned to groups targeted for outplacement planning or inpatient care. During the following year, half of the former were placed in community settings while nearly all of the latter remained in the hospital. Neither the physical health, level of self-care, or psychiatric condition ratings of the two groups changed differentially over that time. However, the mean Morale Inventory score of the outplacement sample improved while that of the in-patient group remained static. Additional analyses were run between three groups - outplacement planning subjects who were released, those who were not released, and inpatient planning men who were not released. These results confirmed those of the first analyses; the only significant difference appeared on the Morale Inventory, the patients who left showing more improvement than the other two groups. The results argue for an increased emphasis on outplacement programs among geriatric patients.  相似文献   
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Intravenous administration of 125I-hCG to 7-8 day pseudopregnant rats resulted in maximum uptake of radioactivity to corpora lutea 2 hours after treatment. At this time tissue/plasma radioactivity ratios on an equal weight basis were: corpora lutea, 70.2 +/- 12.8; ovarian interstitium, 4.6 +/- 0.2; kidney, 2.2 +/- 0.1. No appreciable uptake was seen by adrenals or liver. Radioactivity in corpora lutea was associated primarily with membranes which sedimented at 2000g and when released by heat it was more than 63% bound to luteal LH receptor preparation in vitro. Radioactivity in renal tissue was associated primarily with the 100,000g supernatant fraction and was bound less than 1% to luteal LH receptors in vitro. PGF2alpha significantly reduced uptake (p less than .001) of 125I-hCG by corpora lutea within 30 minutes (-63%) as well as at 1 (-64%), 2 (-75%), 4 (-68%) and 24 hours (-85%). No clear effect of PGF2alpha on uptake of 125I-hCG by ovarian interstitial tissue was seen. Plasma progesterone was significantly decreased (p less than .001) within 30 minutes (-47%; p less than .01) after PGF2alpha treatment and also at 1 (-65%), 2 (-82%), 4 (-68%) and 24 hours (-92%). Two hours after PGF2alpha treatment the content of progesterone in corpora lutea was depressed (-46%; p less than .001). It is suggested that the rapid inhibition of luteal progesterone production induced by PGF2alpha in vivo occurs through a block in gonadotropin uptake by corpora lutea.  相似文献   
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1. Preparations of isolated bladder-urethral junction from cats and guinea-pigs were suspended in Krebs solution (37 degrees C) which was bubbled with carbogen. The urethral lumen was perfused at a very low rate (1-3 ml/h) with Krebs solution. Resistance to flow and changes in longitudinal tension (initial setting 0-5 g) were recorded. In additional experiments, tension changes in urethral circular muscle preparations were registered. 2. The urethral preparations had a basal resistance to flow within the range 5-20 cm H2O. They had a spontaneous contractile activity that was unaffected by atropine 0-1 mug/ml, phenoxybenzamine 0-1 mug/ml, and tetrodotoxin 0-1-0-5 mug/ml, suggesting it was of myogenic origin. 3. The basal characteristics and the drug-induced changes in the perfused urethras were independent of whether the longitudinal tension was recorded isometrically or isotonically, or whether the perfusion was made retrograde or antegrade. Passive changes in longitudinal tension between 0-5 and 2-0 g did not affect the resistance to flow through the urethra. 4. Adrenaline and noradrenaline, 0-01-1 mug/ml, increased longitudinal tension and resistance to flow in the perfused preparations. The effects, which were sustained and concentration-related, were blocked or reversed into inhibition in the presence of phenoxybenzamine, 0-1 mug/ml. This finding suggests that the stimulatory effects were mediated via alpha-receptors. 5. Isoprenaline, 0-001-0-005 mug/ml, relaxed and inhibited the activity in the cat urethral smooth muscle and decreased the resistance to flow both under basal conditions and when the urethra was contracted by noradrenaline or acetylcholine. The inhibitory effects were blocked by propranolol, 0-1 mug/ml, suggesting that they were mediated via beta-receptors. In guinea-pig preparations, no effect of isoprenaline was observed. 6. Acetylcholine, 0-02-0-5 mug/ml, increased the longitudinal tension and the resistance to flow through the urethras. The latter effect was less pronounced than that produced by noradrenaline, especially in the guinea-pig preparations. Noradrenaline was also more effective than ecetylcholine in contracting the circular muscle of the urethra. The effect of acetylcholine was blocked by atropine, 0-1 mug/ml, suggesting that the contractions were mediated through muscarinic cholinoceptors.  相似文献   
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