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81.
An epidemiologic and demographic study of inflammatory bowel disease in black patients 总被引:1,自引:0,他引:1
Alan D. Samuels MD James L. Weese MD Phillip M. Berman MD Joseph B. Kirsner MD PhD 《Digestive diseases and sciences》1974,19(2):156-160
Fifty-eight cases of blacks with inflammatory bowel disease were located in a file containing 1557 patients with these disorders. Certain epidemiologic and demographic characteristics of the two groups, blacks and whites, were compared, including distribution of cases, age at onset, sex incidence, occupational history, marital status, and educational level. No differences were found. Blacks were more likely to have arthritic symptoms and peptic ulcer disease if they had ulcerative colitis. Blacks with Crohn's disease had more fissures than whites. It appears that, once manifested, these diseases are similar in the two groups studied. 相似文献
82.
Primary care physicians in South Carolina were asked about their knowledge, attitudes, beliefs, and services provided to HIV/AIDS patients. The study focused on conditions under which physicians would provide additional services in an effort to develop more effective state policies regarding HIV/AIDS. There was a 66 percent (597/900) response rate. This analysis focuses on a group of 338 physicians that identified themselves as rural (nonurban) physicians. Of the rural physicians responding, 42 percent had not treated a case of HIV/AIDS during the last year and 52 percent had seen only 1 to 9 patients. They identified lack of specialty back-up support, likelihood of losing patients, legal and ethical issues, and lack of community services as the primary barriers to service. Gaps in rural physician knowledge included when to refer HIV/AIDS cases to specialists and information on legal and ethical issues. They, like their urban colleagues, would provide additional services to HIV/AIDS patients with specialty back-up (57 percent), better community and social services support (54 percent), additional training (48 percent), and limited liability (47 percent). The authors conclude that policy changes addressing these areas in the broader contexts of rural health issues would expand access to care for persons with HIV infection in rural states. 相似文献
83.
Yves?JF?GarinEmail author Pascale?Meneceur Francine?Pratlong Jean-Pierre?Dedet Francis?Derouin Frédéric?Lorenzo 《BMC infectious diseases》2005,5(1):18
Background
Leishmaniases are among the most proteiform parasitic infections in humans ranging from unapparent to cutaneous, mucocutaneous or visceral diseases. The various clinical issues depend on complex and still poorly understood mechanisms where both host and parasite factors are interacting. Among the candidate factors of parasite virulence are the A2 genes, a family of multiple genes that are developmentally expressed in species of the Leishmania donovani group responsible for visceral diseases (VL). By contrast, in L. major determining cutaneous infections (CL) we showed that A2 genes are present in a truncated form only. Furthermore, the A2 genomic sequences of L. major were considered subsequently to represent non-expressed pseudogenes [1]. Consequently, it was suggested that the structural and functional properties of A2 genes could play a role in the differential tropism of CL and VL leishmanias. On this basis, it was of importance to determine whether the observed structural/functional particularities of the L. major A2 genes were shared by other CL Leishmania, therefore representing a proper characteristic of CL A2 genes as opposed to those of VL isolates. 相似文献84.
Platelet-melanoma cell interaction is mediated by the glycoprotein IIb- IIIa complex 总被引:3,自引:0,他引:3
A human malignant melanoma cell line (M3Dau) was observed by electron microscopy to interact directly with human platelets and induced platelet aggregation. Fab fragments of a monoclonal antibody MoAb (LYP18), directed against the platelet glycoprotein (GP) IIb-IIIa complex, inhibited platelet-melanoma interactions and platelet-platelet aggregation. M3Dau melanoma cells bind LYP 18 and synthesize IIb-IIIa- like GPs. When the melanoma cells were preincubated with LYP 18, tumor- platelet interaction did not occur, suggesting that the interaction may be mediated by the IIb-IIIa-like GPs present on the melanoma cell surface. Glanzmann's thrombasthenic platelets, lacking GPIIb and IIIa, did not interact with melanoma cells, indicating that the platelet GPIIb-IIIa complex is also necessary for the platelet-melanoma cell interaction. This work demonstrates the importance of the IIb-IIIa-like GPs, present on M3Dau melanoma cells, in mediating tumor-platelet interactions. 相似文献
85.
Metabolic activity of phagocytosing granulocytes in chronic granulocytic leukemia: ultrastructural observation of a degranulation defect 总被引:4,自引:0,他引:4
Cramer E; Auclair C; Hakim J; Feliu E; Boucherot J; Troube H; Bernard JF; Bergogne E; Boivin P 《Blood》1977,50(1):93-106
The functional capacities of granulocytes in patients with chronic granulocytic leukemia are still a subject of controversy, probably due to the heterogeneity of the abnormalities observed from patient to patient. For a better definition of these abnormalities, 14 patients with untreated chronic granulocytic leukemia were studied. The patients were divided into three groups on the basis of the functional activities of their phagocytosing granulocytes. In four patients (group I), the granulocytes were normal in respect to particle ingestion, nitroblue tetrazolium (NBT)-stimulated reduction, cyanide-insensitive oxygen (O2) consumption, superoxide anion (O2-)-stimulated production, hydrogen peroxide (H2O2) production, and iodination. They also had a normal myeloperoxidase (MPO) content. In four patients (group III), the granulocytes were significantly defective in all of these activities. In the six remaining patients (group II), all the initial metabolic steps of the phagocytosing granulocytes (ingestion, NBT reduction, O2 consumption, O2-production, H2O2 production) were normal, as were the MPO content of the granulocytes, while iodination was strikingly decreased. These metabolic features suggested a degranulation defect which was observed ultrastructurally in the only patient studied among these six. The phagocytosing granulocytes of this patient did not degranulate and no deposits of MPO activity were seen in the phagosomes. 相似文献
86.
87.
TCR gamma delta bearing lymphocyte clones with lymphokine-activated killer activity against autologous leukemic cells 总被引:1,自引:0,他引:1
Activated T lymphocytes with the T-cell receptor (TCR) gamma delta (CD3+ and TCR delta 1+) exhibit strong cytotoxic activity against the standard natural killer (NK) and lymphokine-activated killer (LAK) sensitive target cells. In order to test the cytotoxic activity of gamma delta T lymphocytes against autologous leukemic cells, 84 clones of gamma delta T lymphocytes were obtained from the peripheral blood of three acute lymphoblastic leukemia (ALL) patients. Forty-four of these T-cell clones were active against an LAK-sensitive cell line and the other 40 were active against K562, an NK target cell line. In each of the three patients, cytotoxic clones against autologous leukemic cells were obtained. Among the 84 clones, ten were able to kill autologous tumor cells, including eight that lyse the LAK-sensitive target and two with NK activity. The clones were highly cytotoxic, stable, and easily expanded in large quantity. 相似文献
88.
R E Garey G C Daul M S Samuels F A Ragan S A Hite 《The American journal of drug and alcohol abuse》1987,13(1-2):135-144
Methods for determination of PCP in body fluids are presented and a rapid screening method is suggested. The demographics, psychiatric profiles, forensic aspects, and diagnostic problems of PCP abuse are discussed. 相似文献
89.
Arthur A. DeCarlo Nathan Hammes Philip L. Johnson Anantha Shekhar Brian C. Samuels 《Investigative ophthalmology & visual science》2022,63(3)
PurposeIntraocular pressure (IOP) remains the only modifiable risk factor for glaucoma progression. Our previous discovery that stimulation of nuclei within the hypothalamus can modulate IOP, intracranial pressure (ICP), and translaminar pressure difference (TLPD) fluctuations led us to investigate this pathway further. Our purpose was to determine the role of orexin neurons, primarily located in the dorsomedial hypothalamus (DMH) and perifornical (PeF) regions of the hypothalamus, in modulating these pressures.MethodsSprague Dawley rats were pretreated systemically with a dual orexin receptor antagonist (DORA-12) at 30 mg/Kg (n = 8), 10 mg/Kg (n = 8), or vehicle control (n = 8). The IOP, ICP, heart rate (HR), and mean arterial pressure (MAP) were recorded prior to and following excitation of the DMH/PeF using microinjection of the gamma-aminobutyric acid (GABA)A receptor antagonist bicuculline methiodide (BMI).ResultsAdministration of the DORA at 30 mg/Kg significantly attenuated peak IOP by 5.2 ± 3.6 mm Hg (P = 0.007). During the peak response period (8–40 minutes), the area under the curve (AUC) for the 30 mg/Kg DORA cohort was significantly lower than the control cohort during the same period (P = 0.04). IOP responses for peak AUC versus DORA dose, from 0 to 30 mg/Kg, were linear (R2 = 0.18, P = 0.04). The ICP responses during the peak response period (4–16 minutes) versus DORA dose were also linear (R2 = 0.24, P = 0.014). Pretreatment with DORA significantly decreased AUC for the TLPD following stimulation of the DMH/PeF (10 mg/kg, P = 0.045 and 30 mg/kg, P = 0.015).ConclusionsDORAs have the potential to attenuate asynchronous changes in IOP and in ICP and to lessen the extent of TLPDs that may result from central nervous system (CNS) activation. 相似文献
90.
Jessica V. Jasien A. Thomas Read Joseph van Batenburg-Sherwood Kristin M. Perkumas C. Ross Ethier W. Daniel Stamer Brian C. Samuels 《Investigative ophthalmology & visual science》2022,63(1)
PurposeRodent and primate models are commonly used in glaucoma research; however, both have their limitations. The tree shrew (Tupaia belangeri) is an emerging animal model for glaucoma research owing in part to having a human-like optic nerve head anatomy, specifically a collagenous load-bearing lamina. However, the anterior segment anatomy and function have not been extensively studied in the tree shrew. Thus, the purpose of this study was to provide the first detailed examination of the anterior segment anatomy and aqueous outflow facility in the tree shrew.MethodsAqueous outflow dynamics were measured in five ostensibly normal eyes from three tree shrews using the iPerfusion system over a range of pressures. Gross histological assessment and immunohistochemistry were performed to characterize anterior segment anatomy and to localize several key molecules related to aqueous outflow.ResultsAnterior segment anatomy in tree shrews is similar to humans, demonstrating a scleral spur, a multilayered trabecular meshwork and a circular Schlemm''s canal with a single lumen. Average outflow facility was 0.193 µL/min/mm Hg (95% confidence interval, 0.153–0.244), and was stable over time. Outflow facility was more similar between contralateral eyes (approximately 5% average difference) than between eyes of different animals. No significant dependence of outflow facility on time or pressure was detected (pressure–flow nonlinearity parameter of 0.01 (95% % confidence interval, −0.29 to 0.31 CI µL/min/mm Hg).ConclusionsThese studies lend support to the usefulness of the tree shrew as a novel animal model in anterior segment glaucoma and pharmacology research. The tree shrew''s cost, load-bearing collagenous lamina cribrosa, and lack of washout or anterior chamber deepening provides a distinct experimental and anatomic advantage over the current rodent and nonhuman primate models used for translational research. 相似文献