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991.
Two hundred and fifteen consecutive upper gastrointestinal endoscopies were performed. It is evident that the patient population in our setting is quite different when compared with that of a general hospital. The incidence of both gastrointestinal hemorrhage and unknown primary malignant tumor is high. In this group of patients, malignant lesions of the stomach were the most common problem encountered. Primary malignant tumors of the stomach account for the diagnoses in approximately 20 per cent of our patients. Fifty per cent of the patients with cancer of the stomach demonstrated invasion of the lower part of the esophagus or esophagogastric junctional area. The accuracy of endoscopic biopsy was correct in 83 per cent of the patients with malignant tumors of the stomach detected by scopic examination. Thirteen per cent false-negative biopsies occurred from infiltrating diffuse lesions. Endoscopy established the diagnosis of carcinoma of the stomach in one-third of the patients with adenocarcinoma of unknown primary source.  相似文献   
992.
Plasma concentrations of atrial natriuretic peptide (ANP), arginine vasopressin (AVP), plasma renin activity (PRA) and aldosterone, were measured before and after 3 h of hemodialysis in 9 patients with end-stage renal disease on maintenance hemodialysis. Hormone concentrations were also determined in the same patients on a separate occasion after 1 h of ultrafiltration (UF). Plasma concentrations of ANP were significantly higher in the patients with ESRD than in a normal reference population and declined after both 1 h and 3 h of hemodialysis. Plasma concentrations of ANP failed to exhibit a significant decline after 1 h of UF. Plasma AVP concentrations were not significantly different after either hemodialysis or UF, while plasma aldosterone concentrations fell with hemodialysis. The decline in plasma aldosterone concentrations paralleled the decrease in dialysis-induced fall in serum potassium concentrations. There was no correlation between the blood pressures, heart rate, interdialytic weight gain and estimated fluid overload and any of the hormones measured except for the plasma renin activity (PRA) which correlated significantly with the systolic blood pressure. The data suggest that ANP may not be a major factor in blood pressure regulation in normotensive patients with ESRD and its elevation in patients with ESRD is most likely due to fluid overload and atrial distention as well as a possible reduction in its metabolic clearance in renal insufficiency. The fall in plasma ANP following hemodialysis is not due to its removal by dialysis but is most likely due to a reduction in ANP production caused by dialysis-induced correction of hypervolemia.  相似文献   
993.
Pectin, carragheenan, agar gum arabic, cellulose and wheat bran were each fed to rats at a level of 5 to 7% to examine their effect on serum, liver and tissue cholesterol levels. Diets (casein-sucrose diet containing 10-15% soybean oil, or skim milk-wheat flour diet containing 10-15% soybean oil) supplemented with either 0, 0.2, or 0.5% cholesterol were used to test the possibly dietary interactions. Among the fibers tested, pectin displayed the most hypocholesterolemic effect. In some experiments, pectin lowered the level of cholesterol in the serum, liver, and aorta, but it elevated body cholesterol levels. Carragheenan was inconsistent in lowering serum cholesterol levels and tended to increase liver and carcass cholesterol levels. These results probably suggest that pectin and carragheenan can affect the distribution of cholesterol within the body. Gum arabic and agar did not lower serum cholesterol levels and in one case gum arabic elevated them. Furthermore, in some experiments they elevated liver body cholesterol levels. It appears that feeding of gum arabic and agar probably resulted in an expansion of the whole body cholesterol pool. Feeding of wheat bran or cellulose had no significant effect on either serum or liver cholesterol levels. The study indicates that the effect of dietary fiber is dependent on the composition of the diet. Furthermore, while some fibers such as pectin may exhibit a hypocholesterolemic effect in rats, other fibers such as gum arabic and agar may actually elevate serum or tissue cholesterol levels.  相似文献   
994.
The technics of fetoscopy and fetal skin biopsy have expanded our capabilities for antenatal diagnosis of certain hereditary skin disorders (genodermatoses). The fetus and placenta can be visualized directly and skin biopsy specimens can be obtained for light and electron microscopic studies, tissue culture, and biochemical analysis. These technics have been utilized successfully in the prenatal diagnosis or exclusion of epidermolysis bullosa, epidermolytic hyperkeratosis, and harlequin ichthyosis in fetuses known to be at risk for these disorders, and they offer tremendous potential for prenatal diagnosis in a variety of other genodermatoses. Studies of tissue obtained by this procedure will undoubtedly expand our knowledge of the morphogenesis and biochemistry of fetal skin and will provide needed baseline data for the further development of these technics.  相似文献   
995.
A number of ring substituted(E)-4-phenyl-3-buten-2-ones including dehydrozingerone were studied for their oxygen radical scavenging properties. They scavenged superoxide and hydroxyl radicals to an appreciable extent. Good correlation (r = 0.87) was obtained between superoxide scavenging and antiinflammatory activity. The correlation was not significant with the hydroxyl scavenging activity.  相似文献   
996.
997.
It has been shown that the level of estrogen receptors (ER), and to some extent progesterone receptors (PR), correlate to a high degree to the response to endocrine therapy in advanced breast cancer patients. To evaluate the prognostic value of ER/PR in early breast cancer, 80 patients with stages I and II were studied. They all underwent modified radical mastectomy. Patients with stage I disease (negative LN) received no further treatment, while those with stage II received standard adjuvant chemotherapy. All the patients were followed for 4 years. The ER and PR were measured in each primary tumor by the glycerol density gradient method. Values of 10 fmole/mgm protein or greater were considered positive (+) and less than 10 fmole/mgm were considered negative (-). The results revealed: (1) Fifty-two patients (65%) had ER+, of which 44 (85%) were also PR+; 28 patients had ER-, of which 24 were also PR- (p less than 0.0001). (2) ER/PR correlated with age as 71% of the patients over age 50 had ER+/PR+, compared to 33% of those under age 50 (p less than 0.05). (3) Postmenopausal patients had a higher incidence of ER+/PR+. (4) Primary tumors less than 2 cm in size had higher ER+; 71% in those with stage I and 80% in stage II. (5) Fifty-eight per cent (38) of patients with ductal carcinoma had ER+/PR+, compared to 67% (4) with lobular carcinoma. (6) The disease-free survival of patients with ER+ tumors was significantly longer than those with ER- tumors (p less than 0.005) both in positive and negative LN patients. The same was true for PR+ compared to PR- (p less than 0.005), but only in those with stage II disease. The overall survival rates were similarly significant in favor of ER+ and PR+ patients (p less than 0.025), but only in stage II disease. It seems that the status of steroid hormone receptors has a major prognostic factor second only to the LN status.  相似文献   
998.
Three patients, ages 13 months, 13 years, and 16 years, with renovascular hypertension complicating neurofibromatosis underwent vascular reconstruction with good results. A review of these patients, plus 47 additional patients from the literature, constitutes the basis of this report. The standard intravenous pyelogram revealed abnormalities in only 46 per cent of the patients. Definitive diagnosis required angiography and selective renal vein renin determinations. Unilateral and bilateral lesions were seen with equal frequency. Associated arterial abnormalities were common. Medical treatment and balloon angioplasty failed to control the blood pressure in all patients. Surgical therapy, either nephrectomy or vascular reconstruction, cured or significantly improved 95 per cent of the patients. Although one primary goal of operation is renal salvage, 40 per cent of the patients in this review underwent nephrectomy to control their hypertension.  相似文献   
999.
An MR line scan protocol has been used to measure relaxation parameters (T1 and T2) in isolated, blood perfused rabbit hearts at various blood oxygenations. Hearts were retro-gradely perfused at 37°C with a cardioplegic solution (modified St. Thomas' solution) containing sheep red blood cells and adenosine (1 mM) to maximally vasodilate the coronary vascular bed. Arresting the hearts eliminated motion complications and minimized arteriovenous oxygenation differences. The authors have found that under conditions of stable flow, there is a strong correlation between T2 in myocardial septa and hemoglobin (Hb) saturation, while tissue T1 is virtually independent of blood oxygenation. These effects are believed to be due to the paramagnetic agent deoxyhemoglobin.  相似文献   
1000.
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