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排序方式: 共有10000条查询结果,搜索用时 276 毫秒
91.
Neil M. Rofsky Donald J. Pizzarello Jeffrey C. Weinreb Michael M. Ambrosino Carl Rosenberg 《Journal of magnetic resonance imaging : JMRI》1994,4(6):805-807
Pregnant mice were exposed to one of five regimens at 9.5 days of gestation: no treatment (group 1), intraperitoneal injection of normal saline (group 2), intraperitoneal injection of gadopentetate dimeglumine (group 3), intraperitoneal injection of gadopentetate dimeglumine and magnetic resonance (MR) exposure (group 4), and MR exposure alone (group 5). At 18 days of gestation, the mice were sacrifice and fetuses were removed and examined for the following end points: litter size, number alive or dead, fetal weight, extremity morphology, eye and ear development, and appearance of the head. A total of 739 fetuses were analyzed: group 1 (n = 161), group 2 (n = 149), group 3 (n = 142), group 4 (n = 136), and group 5 (n = 151). The only statistically significant difference was a lower mean fetal weight in the saline-injection group compared with the control group. The results show that MR exposure with and without gadopentetate dimeglumine had no adverse effect on the end points analyzed. 相似文献
92.
Role of substance P in several models of bladder inflammation 总被引:1,自引:0,他引:1
Judith Luber-Narod Tammy Austin-Ritchie Carl Hollins III Mani Menon Rajwant K. Malhotra Stephen Baker Robert E. Carraway 《Urological research》1997,25(6):395-399
Substance P (SP) is a peptide found in the sensory nervous system which has multiple biologic effects including stimulation of muscle contraction, pain nociception, immune cell functions, plasma extravasation and a constellation of inflammatory effects. Here we investigate the role of SP in several animals models of bladder inflammation. Using the female Lewis rat, inflammation was induced using either xylene, lipopolysaccharide (LPS) or polyinosinic-polycytidylic acid (polyIC). Inflammation occurred rapidly (4 h) and was maintained in each model for at least 7 days. Each of these protocols decreased the bladder content of immunoreactive SP by approximately 50%, suggesting enhanced release. There was no change in the urinary frequency of these animals over 3 weeks, suggesting that urinary frequency changes are not mediated by acute inflammation. We also found that the SP receptor (NK1) antagonist, (?)CP96345, was unable to block the inflammation produced by polyIC, suggesting that SP is not an obligatory mediator of immune cell stimulation in this model. 相似文献
93.
How Cluster Headache is Explained as an Intracavernous Inflammatory Process Lesioning Sympathetic Fibers 总被引:2,自引:0,他引:2
SYNOPSIS
A large body of evidence points to an inflammatory process in the cavernous sinus and tributary veins as being primarily responsible for cluster headaches. The inflammation obliterates the venous outflow from the cavernous sinus on one side and injures the through-running sympathetic fibers to the eye, upper eye lid, forehead skin, and the intracranial internal carotid artery and its branches. The active period ends when the inflammation is suppressed and the sympathetic fibers partially or fully recover. Evidence is presented that the symptoms suggestive of an enhanced parasympathetic activity during attacks may alternatively be explained as local pain fiber activation or a stasis in the outflow from the cavernous sinus. Vasodilator agents like nitroglycerin induce an attack by enhancing the venous load on the cavernous sinus. Constriction of the proximal intracranial internal carotid artery, spontaneously induced by tressful pain activation of the perivascular sympathetic nerves, or by exogenous administration of serotonin 1 D-like receptor agonists or oxygen, terminates the venous load and thus the pain and associated symptoms. 相似文献
A large body of evidence points to an inflammatory process in the cavernous sinus and tributary veins as being primarily responsible for cluster headaches. The inflammation obliterates the venous outflow from the cavernous sinus on one side and injures the through-running sympathetic fibers to the eye, upper eye lid, forehead skin, and the intracranial internal carotid artery and its branches. The active period ends when the inflammation is suppressed and the sympathetic fibers partially or fully recover. Evidence is presented that the symptoms suggestive of an enhanced parasympathetic activity during attacks may alternatively be explained as local pain fiber activation or a stasis in the outflow from the cavernous sinus. Vasodilator agents like nitroglycerin induce an attack by enhancing the venous load on the cavernous sinus. Constriction of the proximal intracranial internal carotid artery, spontaneously induced by tressful pain activation of the perivascular sympathetic nerves, or by exogenous administration of serotonin 1 D-like receptor agonists or oxygen, terminates the venous load and thus the pain and associated symptoms. 相似文献
94.
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96.
Jesper Carl Thomas Bro Christensen Hans von der Maase 《Acta oncologica (Stockholm, Sweden)》1992,31(7):749-753
This study presents an analysis on longitudinal tumour marker series in twenty-two patients with non-seminomatous germ cell cancers treated with cisplatinum (DDP) based combination chemotherapy. Series of alphafoetoprotein (AFP), human chorionic gonadotropin (HCG) and lactate dehydrogenase (LDH) were analyzed applying a dynamic mathematical marker model. The model analysis provided quantitated values for growth rate and treatment response in the marker producing cells. The analysis showed that LDH had to be above 2 000 U/l to be a trustworthy tumour marker. HCG producing cells tended to grow faster than AFP producing cells, and were 3-5-fold more sensitive to the chemotherapy given than AFP producing cells. Treatment response versus DDP dose appeared to be bi-phasic, but with no significant change in treatment efficiency within the given range of DDP doses. 相似文献
97.
98.
Mark F. Cotton Peter R. Donald Johan F. Schoeman Lana E. Van Zyl Cor Aalbers Carl J. Lombard 《Child's nervous system》1993,9(1):10-15
Intracranial pressure (ICP) monitored shortly after admission over a period of 1 h in 31 children with tuberculous meningitis (TBM) was significantly higher (median 22.5 mm Hg, range 8.4–50.9 mmHg) in 19 children with laboratory evidence of the syndrome of inappropriate antidiuretic hormone secretion (SIADH) than in 12 children without such evidence (median 16.2 mmHg, range 5.8–42.5 mmHg; P = 0.027). Neither plasma nor cerebrospinal fluid arginine vasopressin (AVP) was related to ICP (r = 0.33 and 0.13 respectively). Mean arterial pressure (MAP) was measured in 23 children and a moderate correlation was found with plasma AVP (r = 0.62; P = 0.0019). In TBM, plasma AVP may be secreted as a response to raised ICP in an effort to raise MAP and maintain cerebral perfusion pressure. In this setting excess fluid may be inappropriately retained, leading to hyponatremia and hypo-osmolemia. 相似文献
99.
Background. Although it has been established that basal cell carcinoma is an uncommon diagnosis in black patients, the morpheaform subtype is very rare among these individuals.
Objective. The objective is to present two cases of morpheaform basal cell carcinoma in African-American patients.
Methods. This is a case series and a literature review using the Ovid Medline Database. Key words used in the search include "basal cell carcinoma,""African American,""black,""African,""negros,""morpheaform,""sclerosing,""fibrosing," and "scar-like basal cell carcinoma." The Ovid Medline Database was searched from 1966 to present and was restricted to the English language.
Results. A review of the Emory Dermatology clinic charts from 1989 to 2004 revealed two black patients with morpheaform basal cell carcinomas.
Conclusions. Although extremely rare, morpheaform pattern basal cell carcinoma must be considered in the differential diagnosis for black patients presenting with nonhealing lesions. 相似文献
Objective. The objective is to present two cases of morpheaform basal cell carcinoma in African-American patients.
Methods. This is a case series and a literature review using the Ovid Medline Database. Key words used in the search include "basal cell carcinoma,""African American,""black,""African,""negros,""morpheaform,""sclerosing,""fibrosing," and "scar-like basal cell carcinoma." The Ovid Medline Database was searched from 1966 to present and was restricted to the English language.
Results. A review of the Emory Dermatology clinic charts from 1989 to 2004 revealed two black patients with morpheaform basal cell carcinomas.
Conclusions. Although extremely rare, morpheaform pattern basal cell carcinoma must be considered in the differential diagnosis for black patients presenting with nonhealing lesions. 相似文献
100.