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1.
Estrogenic microenvironment generated by organochlorine residues in adipose mammary tissue modulates biomarker expression in ERα-positive breast carcinomas
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2.
Information collected by the National Gay Rights Advocates in 1986 and by the authors in the spring of 1987 was used to determine the extent to which the states currently regulate the practices of the health insurance industry specific to acquired immunodeficiency syndrome (AIDS). Of the 10 states reporting the greatest number of AIDS cases, six prohibit insurers form denying coverage to group policy applicants because of human immunodeficiency virus (HIV) infection. These findings refer only to the status of state regulatory activity specific to AIDS. 相似文献
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Toxic-shock-syndrome toxin-1 (TSST-1), a 22-kilodalton (kDa) polypeptide, was proteolyzed by papain, generating three distinct fragments, identified as 16, 12, and 10 kDa (based on molecular masses estimated from the predicted amino acid sequence). The NH2-terminal sequence analysis of the fragments indicated that the peptide bonds between Tyr-52 and Ser-53 and between Gly-87 and Val-88 were cleaved. Functional activity, evaluated through enzyme-linked immunosorbent and inhibition assays, was demonstrated only with the 16- and 12-kDa fragments. The presence of homologous and heterologous antigenic determinants on the fragments was demonstrated by immunoblotting. In in vitro stimulation of human peripheral blood mononuclear cells, the 12-kDa fragment was significantly (P = .003) more active than the 16-kDa fragment. The former composed 75% of the latter and occupied the COOH-terminal portion of the holotoxin. The functional domains were located on two-thirds of the TSST-1 molecule, toward the COOH-terminal end, and mitogenicity apparently was separable from serological activity. 相似文献
5.
Evaluation of contractile state by maximal ventricular power divided by the square of end-diastolic volume 总被引:8,自引:0,他引:8
BACKGROUND. Maximal ventricular power (PWRmax) reflects contractile state and has the potential to be noninvasively determined. However, its sensitivities to preload, afterload resistance, and inotropic state are incompletely defined. The present study determines these dependencies and proposes a novel power-based contractile index that is little altered by load. METHODS AND RESULTS. Seven open-chest, autonomically blocked dogs were instrumented with a proximal aortic flow probe, central aortic and ventricular micromanometers, and a conductance catheter for ventricular chamber volume. Preload was transiently reduced by left atrial hemorrhage, and afterload was increased by intra-aortic balloon inflation. Inotropic state was pharmacologically altered by lidocaine, dobutamine, propranolol, or verapamil. PWRmax was highly preload sensitive, altering 1.7 +/- 0.1-fold a given percent change in end-diastolic volume (EDV). This preload dependence was reduced by dividing PWRmax by EDV but was virtually eliminated when PWRmax was divided by EDV2. This latter index also displayed little change in response to as much as 60% increases in afterload resistance. PWRmax/EDV2 varied directly with inotropic state, correlating to both the slope (Ees) of the end-systolic pressure-volume relation (PWRmax x 1,000/EDV2 = 0.31 x Ees - 0.04, r = 0.82, p less than 0.001) and the slope (A) of the dP/dtmax-EDV relation (PWRmax x 1,000/EDV2 = 0.025 x A + 0.02, r = 0.86, p less than 0.001). PWRmax values determined from the product of ventricular pressure and flow versus central aortic pressure and flow were nearly identical over a broad loading range, indicating that PWRmax may be noninvasively assessed (i.e., without requiring left ventricular chamber pressure). CONCLUSIONS. PWRmax divided by EDV2 provides a measure of contractile function that is little influenced by loading conditions and has potential for noninvasive clinical use. 相似文献
6.
Acute appendicitis: CT and US correlation in 100 patients 总被引:19,自引:1,他引:18
7.
Perforated colorectal neoplasms: correlation of clinical, contrast enema, and CT examinations 总被引:2,自引:0,他引:2
Hulnick DH; Megibow AJ; Balthazar EJ; Gordon RB; Surapenini R; Bosniak MA 《Radiology》1987,164(3):611-615
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm. 相似文献
8.
Effect of linoleic and oleic acids on blood pressure, blood viscosity, and erythrocyte cation transport 总被引:1,自引:0,他引:1
F M Sacks M J Stampfer A Munoz K McManus M Canessa E H Kass 《Journal of the American College of Nutrition》1987,6(2):179-185
It has been proposed that dietary linoleic acid lowers blood pressure (BP) by being converted to arachidonic acid and prostanoids of the two-ene series. We tested the effects of linoleic acid on plasma arachidonic acid, blood pressure, blood viscosity, and RBC cation transport. Oleic acid, the major dietary monounsaturated fat and which is not a prostanoid precursor, was used as a control. Seventeen adults consumed 23 g/d of linoleic acid or oleic acid provided by genetic variants of safflower seed, each for 4 weeks in a double-blind crossover design. Linoleic and oleic acids were enriched significantly in the plasma cholesteryl esters, phospholipids and triglycerides during the respective periods of supplementation but there was no increase in arachidonate. Mean BP was 116.1/76.8 during ingestion of oleic and 113.6/74.6 during ingestion of linoleic acid (p = 0.09 systolic, p = 0.12 diastolic). The power of the study was over 75% for detecting a significant (p less than 0.05) effect of 4 mm Hg in systolic BP or diastolic BP. Whole blood and plasma viscosity, and RBC Li/Na countertransport, Na/K cotransport, and Na pump systems (Vmax) were unchanged during the protocol. Therefore, variations in dietary linoleic or oleic acids are unlikely to have major effects on BP or on several membrane-dependent erythrocyte functions related to hypertension. 相似文献
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10.
During a 5-year period 32 children and adolescents 4 to 18 years old underwent 35 extracorporeal shock wave lithotripsy (ESWL* ) treatments for 37 calculi. The unmodified Dornier HM3 lithotriptor was used in 21 cases (60 percent) while the remaining cases were treated with the Siemen Lithostar lithotriptor. The HM3 necessitated general anesthesia in 67 percent of patients and the Lithostar necessitated intravenous sedation in 86 percent. The majority of pediatric lithotripsy treatments were performed on an outpatient basis (24) or during an overnight hospital stay (3) while 8 were done on an inpatient basis. Of the 37 stones treated with 1 ESWL session 68 percent resolved, 19 percent had residual fragments less than 4 mm., 8 percent had residual fragments greater than 4 mm. and 5 percent required an endoscopic procedure for resolution. When success rates by lithotriptor were examined no significant difference between the 2 machines was identified although the HM3 treated larger stones (p = 0.0499). There were no statistical differences in regard to success and the use of stents, patient age or stone location between the 2 lithotriptors. Three patients required adjuvant procedures, and complications and morbidity developed in 2 and 5, respectively. All children or parents were contacted for followup (range 7 to 67 months). One child required ESWL for a new stone while another passed a stone without intervention. Only 1 child with a residual fragment less than 4 mm. became symptomatic but needed no intervention while 1 of 3 with fragments greater than 4 mm. needed intervention. No patients required open or percutaneous intervention. 相似文献