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51.
K N Tsiquaye B Portmann G Tovey H Kessler S Hu X Z Lu A J Zuckerman J Craske R Williams 《Journal of medical virology》1983,11(3):179-189
There are reports in the literature that infection with hepatitis A virus in hepatitis B carriers can result in resolution of the carrier state. In an attempt to induce clearance of the carrier state of hepatitis B virus in two persistently infected chimpanzees, the chimpanzees were infused with documented non-A, non-B infectious material. Biochemical and histopathological evidence of hepatitis was accompanied by the unique abnormalities of endoplasmic reticulum associated with non-A, non-B hepatitis in the chimpanzees. Elevation of alanine aminotransferase was accompanied by fourfold reduction in one chimpanzee and sixfold reduction in the other in the plasma levels of HBV-associated DNA polymerase activity and simultaneously by twofold reduction in the concentration of hepatitis B surface antigen in both chimpanzees. A mediator may account for these changes in markers of hepatitis B virus infection, and this mechanism may also explain the occurrence of spontaneous regression in some persistently infected carriers. The significance of transient red cell anaemia in non-A, non-B hepatitis, which was observed in one of the chimpanzees, is yet to be established. 相似文献
52.
53.
The basis of the FDA's decision on breast implants. 总被引:6,自引:0,他引:6
D A Kessler 《The New England journal of medicine》1992,326(25):1713-1715
54.
By polyacrylamide gel electrophoresis, Duck/Mississippi/75 virus was shown to contain five different types of polypeptides of mol. wt. ranging from 76 X 1O(3) to 43 X 10(3), two of which were glycosylated (mol. wt. 76 X 10(3) and 57 X 10(3). A comparison of this data with similar results obtained using Yucaipa and Newcastle disease virus (NDV) revealed a similarity with NDV, concerning the number, position and mol. wt. of the polypeptides. Haemagglutinating and neuraminidase properties are associated with surface glycoproteins which represent at least 40% of the virus protein. After KCl and Triton X-100 treatment and centrifugation on linear sucrose density gradients (10 to 25%, w/w) it was possible to isolate glycoprotein VP1 of mol. wt 76 X 10(3) with which haemagglutinating and neuraminidase activities were associated. 相似文献
55.
The emigratory behavior and locomotor activity of yellow-eyed (y/y), wildtype (+/+), and heterozygous (+/y) house flies was examined at 8 fc (86 lx) and 1600 fc (17,223 lx) light intenstities. At 8 fc, emigration rate and activity of the y/y flies was similar to that of the +/+ and +/y flies. However, at 1600 fc, the y/y flies emigrated at twice the rate and showed an activity of about one-third that of the other genotypes. The behavior of the +/+ and +/y flies remained similar regardless of the experimental design or light intensity. The excessive neural stimulation by high-intensity light resulting from reduced shielding pigments led to behavioral modifications in the visual and tactile responses of the y/y flies.This research was supported in part by grants from the CUNY Faculty Research Award Program (No. 1103) and NIH Biomedical Research Support Grant 5-S05-R-07064. 相似文献
56.
Baer L Jacobs DG Meszler-Reizes J Blais M Fava M Kessler R Magruder K Murphy J Kopans B Cukor P Leahy L O'Laughlen J 《Psychotherapy and psychosomatics》2000,69(1):35-41
BACKGROUND: The present study was designed to develop a briefer screening scale of approximately 10 items which maintained the validity of the Zung Self-Rating Depression Scale in a sample similar to that attending National Depression Screening Day (NDSD), as well as a more general audience. METHODS: We first administered 70 items from a variety of existing rating scales to 40 subjects who answered an ad for depressed subjects and 55 who answered an ad for non-depressed subjects, all of whose diagnoses were confirmed by the Structured Clinical Interview for DSM-IV (SCID). Based on the correlation between each item and the diagnostic criterion, we reduced the number of items to 17 which we then administered to another 45 subjects who answered an ad similar to that used for NDSD and also underwent a SCID interview. Based on these results, we arrived at the final 10-item Harvard Department of Psychiatry/NDSD scale (HANDS) with the assistance of the item-response theory. The items are scored for frequency of occurrence of each symptom over the past 2 weeks. Total scores range from 0 to 30. RESULTS: The 10-item scale (HANDS) has good internal consistency and validity: a cutpoint score of 9 or greater gave sensitivity of at least 95% in both studies. Although specificity was lower for all scales in the self-selected population, the HANDS performed at least as well as the 20-item Zung Scale, the 21-item Beck Depression Inventory-II and the 15-item Hopkins Symptom Depression Checklist. CONCLUSION: The 10-item HANDS performs as well as other widely used longer self-report scales and has the advantage of briefer administration time. 相似文献
57.
The erythrocyte sedimentation rate in congestive heart failure 总被引:1,自引:0,他引:1
H L Haber J A Leavy P D Kessler M L Kukin S S Gottlieb M Packer 《The New England journal of medicine》1991,324(6):353-358
BACKGROUND AND METHODS. Physicians have long believed that the erythrocyte sedimentation rate is low in patients with congestive heart failure, but this concept is based on a misinterpretation of the results in a single report published in 1936. To reevaluate this concept in the modern era, we measured the sedimentation rate in 242 patients who were referred for treatment of chronic heart failure. RESULTS. The sedimentation rate was low (less than 5 mm per hour) in only 24 patients (10 percent) but was increased (above 25 mm per hour) in 50 percent. Patients with low or normal sedimentation rates (less than or equal to 25 mm per hour) had more severe hemodynamic abnormalities than patients with elevated rates: lower cardiac index (mean +/- SEM, 1.7 +/- 0.1 vs. 2.0 +/- 0.1 liters per minute per square meter of body-surface area) and higher mean right atrial pressure (mean +/- SEM, 12 +/- 1 vs. 9 +/- 1 mm Hg) (both P less than 0.0001). New York Heart Association functional class IV symptoms were present in 66 percent of the patients with a low or normal sedimentation rate, as compared with 42 percent of those with elevated rates (P less than 0.0001). After one to three months of therapy, patients whose sedimentation rates decreased showed little hemodynamic or clinical response to treatment, whereas both cardiac performance and functional status improved in patients whose rates increased (P less than 0.02 for the comparison between groups). The sedimentation rate was correlated with the plasma fibrinogen level (r = 0.64, P = 0.0025), and changes in the sedimentation rate during treatment were correlated inversely with changes in mean right atrial pressure (r = -0.57, P = 0.0002). During long-term follow-up, patients with low or normal sedimentation rates had a worse one-year survival than patients with elevated rates (41 vs. 66 percent, P = 0.01). CONCLUSIONS. These data indicate that the erythrocyte sedimentation rate is correlated with the severity of illness in patients with chronic heart failure. Because of its lack of discriminatory power, however, the test is of limited value in the clinical management of this disorder. 相似文献
58.
Substance P and somatostatin metabolism in sympathetic and special sensory ganglia in vitro 总被引:4,自引:0,他引:4
Mechanisms regulating the content of the putative peptide transmitters, substance P and somatostatin, were examined in several neuronal populations in culture. Substance P levels increased more than 25-fold within 48 h in sympathetic neurons in the explanted rat superior cervical ganglion, and remained elevated for 4 weeks. Identity of the peptide was authenticated by combined high pressure liquid chromatography-radioimmunoassay. Veratridine prevented the increase of substance P in vitro, and tetrodotoxin blocked the veratridine effect, suggesting that sodium ion influx and membrane depolarization prevent peptide elevation. Veratridine (or potassium)-induced membrane depolarization released substance P into the culture medium through a calcium-dependent process. Consequently, at least some veratridine effects are attributable to release and subsequent depletion of ganglion peptide. However, the inhibitory effects of veratridine were far greater than could be accounted for by the quantity of peptide released, suggesting a separate influence on net synthesis (synthesis less catabolism) of substance P. Viewed in conjunction with previous in vivo studies, our observations suggest that trans-synaptic impulses, through the mediation of postsynaptic sodium flux, release substance P from sympathetic neurons and also regulate intracellular peptide metabolism. To determine whether the processes regulating substance P in sympathetic neurons reflect generalized mechanisms, a different peptide, somatostatin, was examined in sympathetic neurons; moreover, substance P was examined in a different neuronal population, special sensory neurons in the nodose ganglion. Substance P levels increased significantly in both sympathetic and sensory neurons after explantation, and somatostatin levels increased in sympathetic neurons. In each instance, the increase was dependent upon the presence of the calcium ions. Moreover, these increases were all prevented by veratridine, in a tetrodotoxin-sensitive manner. Our observations suggest that common regulatory mechanisms govern peptide transmitter metabolism in diverse neuronal populations. 相似文献
59.
We describe two cases of short-segment Hirschsprung's disease associated with neuronal colonic dysplasia. The recurrence of postoperative symptoms of bowel obstruction may be due to the combined occurrence of these two disorders. 相似文献
60.
Severe combined immunodeficiency with B lymphocytes: in vitro correction of defective immunoglobulin production by addition of normal T lymphocytes. 总被引:3,自引:2,他引:3
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R C Seeger R A Robins R H Stevens R B Klein D J Waldman P M Zeltzer S W Kessler 《Clinical and experimental immunology》1976,26(1):1-10
A 6 1/2-month-old male with severe combined immunodeficiency (SCID) had a low percentage and number of T cells (11%; 241/mm3) and a high percentage and number of B cells (52%; 1187/mm3) and null cells (37%; 868/mm3). In vitro studies were performed to determine if this child's primary defect involved differentiation of both T and B lymphocytes or if failure of B lymphocytes to differentiate into immunoglobulin producing cells was secondary to T lymphocyte abnormalities. Immunoglobulin production by lymphocytes in response to polyclonal mitogens (pokeweed mitogen and foetal calf serum) was measured by pulse-labelling cells with 3H-leucine and then precipitating cytoplasmic and secreted immunoglobulins with polyvalent anti-human immunoglobulin and S. aureus (Cowan strain I) protein A. The patient's lymphocytes did not synthesize immunoglobulins in vitro in response to mitogens. They did not suppress synthesis of immunoglobulins by normal lymphocytes. However, addition of normal purified T cells, which themselves did not synthesize immunoglobulins, enabled the patient's B lymphocytes to become immunoglobulin synthesizing and secreting cells. Gamma, mu, and light chains were secreted. This suggests that the primary abnormality was in the T-cell axis at the level of lymphoid stem cells or prothymocytes and that failure of B lymphocytes to become immunoglobulin-producing cells was secondary to this defect. 相似文献