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A role of insular cortex in cardiovascular function 总被引:5,自引:0,他引:5
D A Ruggiero S Mraovitch A R Granata M Anwar D J Reis 《The Journal of comparative neurology》1987,257(2):189-207
We sought to determine whether the insular cortex contributes to the regulation of arterial blood pressure (AP). Responses to electrical and chemical stimulation of the cortex were studied in the anesthetized, paralyzed, and artificially ventilated Sprague-Dawley rat. The insular cortex was initially defined, anatomically, by the distributions of retrogradely labeled perikarya following injections of wheat germ agglutinin-horseradish peroxidase (WGA-HRP) into the nucleus tractus solitarii (NTS). Injections of WGA-HRP into the insular cortex anterogradely labeled terminals in cardiopulmonary and other divisions of the NTS and confirmed projections revealed by retrograde tracing experiments. Electrical stimulation of the insular cortex elicited elevations of AP (less than or equal to 50 mm Hg) and cardioacceleration (less than or equal to 40 bpm). The locations of the most active pressor sites corresponded closely to the locations of retrogradely labeled cells in layer V of granular and posterior agranular areas of the insular cortex (areas 14 and 13) and the extreme capsule. Maximal pressor responses were obtained at a stimulus intensity of three to five times threshold current of 20-30 microA. Responses elicited mostly with higher-threshold currents were also mapped in areas 2a and 5lb and the claustrum and within the corpus callosum. Unilateral injections into the insular pressor area of the excitatory amino acid monosodium glutamate (L-Glu; 0.05 nmol to 10 nmol) or the rigid structural analogue of L-Glu, kainic acid (KA) (0.4 nmol) (which specifically excite perikarya), caused topographically specific elevations in AP and tachycardia. During the course of the anatomical transport studies, new findings were obtained on the organization and characteristics of the cortical innervation of the NTS and the nucleus reticularis parvocellularis. Topographic relationships between the cortex and the NTS were organized in a more complex manner than previously thought. Cells projecting to caudal cardiopulmonary segments of the NTS were fewer and generally located ventrally and caudally and in a more restricted area than cells projecting rostrally or to the parvicellular reticular formation. Anterograde transport data revealed new presumptive terminal fields in dorsolateral, ventral, periventricular, and commissural regions of the NTS, including an area overlapping the terminal field of the aortic baroreceptor nerve. We conclude that neurons within an area of the insular cortex projecting to multiple brainstem autonomic nuclei, including a region of the NTS innervated by baroreceptor afferents, increase arterial blood pressure and heart rate.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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Anwar B Bataineh Zakereyya S Albashaireh Abdalla M Hazza'a 《Quintessence international, dental digest》2002,33(8):613-617
OBJECTIVE: The aim of this study was to investigate and analyze the angulation of and the various indications for removal of mandibular third molars in Jordanians as a representative Arab sample. METHOD AND MATERIALS: The data included in this retrospective study were obtained from the clinical and radiographic records of 1,282 patients undergoing mandibular third molar surgery during a 5-year period from 1994 to 1999. The indications for removal of the mandibular third molars were classified in accordance with age and gender. The angular position of mandibular third molars was registered. RESULTS: A total of 2,252 mandibular third molars were removed from 740 male patients (57.7%) and 542 female patients (42.3%) aged 14 to 67 years. Pericoronitis was the most common indication for surgery, affecting 1,055 teeth (46.8%). Caries was observed in 519 third molars (23.0%). The vertical angular position was most commonly found (1,383 teeth; 61.4%) followed by the mesioangular position (407 teeth; 18.1%). CONCLUSION: The results obtained in this study are similar to those reported in earlier studies carried out elsewhere, although the incidence of periodontitis among Jordanians was significantly higher and occurred in older patients, and prophylactic removal was performed less frequently than has been reported in other countries. 相似文献
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S. Giridharan B. Vakkalanka M. S. Anwar J. I. Geh J. Glaholm M. Churn† F. Adab‡ R. Grieve§ C. McConkey¶ A. Hartley 《Colorectal disease》2005,7(1):43-46
BACKGROUND: The addition of short course pre-operative radiotherapy to total mesorectal excision reduces local recurrence in resectable adenocarcinoma of the rectum. In a previous retrospective study potential factors associated with early complications following this combination were identified. The aim of this study was to examine these relationships in a prospective multicentre audit. METHODS: One hundred and seven patients who received short course pre-operative radiotherapy in four cancer centres between 1 October 2001 and 30 September 2002 were included. Data including patient age, radiotherapy field length, overall treatment time, operation type, surgical outcomes and complications occurring within 3 months of the 1st day of radiotherapy were collected. These were compared and combined with the previously studied cohort of 176 patients treated at one centre between 1st January 1998 and 31st December 1999. RESULTS: In the prospective cohort only patient age (P=0.001) was significantly associated with acute complications. However, both the overall treatment time (median 9.0 vs 11.0 days P <0.0001) and field length (median 16.6 vs 17.0 cm P=0.03) were significantly shorter in this cohort when compared to the previous retrospective study. In patients from both studies (n=283), increasing age (P=0.002) and field length (independent of operation type) (P=0.02) were independently associated with an increased risk of acute complications. CONCLUSIONS: This study suggests that meticulous selection of patients for short course pre-operative radiotherapy and smaller planning target volumes may be associated with a lower risk of acute complications. The use of MRI scanning to stage pelvic disease may reduce the number of patients with R1 resections receiving short course pre-operative radiotherapy. 相似文献
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Up to date 2 species of Mallophaga have been reported from birds in Iran. Further studies in Tehran area showed that the wild birds harbour more lice. The following species of Mallophage are reported for the first time from birds in Iran. Anaticola crassicornis from Anas clypeata, Laemobothrion maximum from Falco tinnunculus Laemobothrion sp. from Aquila chrysaetos Alcedoecus annulatus from Alcedo athis, Colpocephalum pectinatum and Strigiphilus sp. from Streptopelia turtur, Amrysidea fulvomaculata from Coturnix coturnix, philopterus picae from pica pica, Philopterus ocellatus and Colpocephalum pectinatum from Athene noctua, Philopterus sp. from Turdus ruficollis, Upupicola upupae from Upupa epops, Amyrsidea hexapilosus from Phasianus colchicus, Colpocephalum sp. from Falco cherrug. 相似文献
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In vitro adherence of radioactively labeled Escherichia coli in normal and cystitis-prone females. 下载免费PDF全文
Numerous investigators report data obtained using an in vitro quantitative assay for measuring bacterial adherence to epithelial cells. We found this assay to contain significant sources of error in the large variation in number of bacteria bound per cell and in the dependence on the investigator's visual counting of bacteria bound per cell. In the modified assay described here, we eliminated the need for visual counting of bacteria by incorporating the use of radioactively labeled Escherichia coli. This allowed quantitation of bacterial adherence to as many as 50,000 vaginal cells, whereas the visual counting system limits the determination to perhaps 50 cells. We feel that the use of radioactively labeled bacteria in place of the visual counting system increases the validity and sensitivity of this assay. Using the modified method, we found no statistically significant differences among values for adherence of E. coli type 04 to the vaginal cells of control and cystitis-prone women at either pH 6.4 or 4.0. 相似文献
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Nisar PJ Zaitoun AM Damera A Hodi Z Tierney GM Beckingham IJ 《Journal of clinical pathology》2002,55(12):967-969
A 45-year-old female patient underwent right hemihepatectomy for metastatic rectal adenocarcinoma. Preoperative imaging demonstrated an area of focal nodular hyperplasia (FNH) in segment VIII and metastatic carcinoma in segment VI of the liver. Gross and microscopic examination of the former lesion showed features typical of FNH with an intralesional metastatic adenocarcinoma. To the best of our knowledge, this is the first reported case of metastatic adenocarcinoma located within a lesion of FNH. The possibility of a pathogenetic association behind this occurrence is discussed. 相似文献
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Chromosomal aberrations and micronucleus frequency in nurses occupationally exposed to cytotoxic drugs 总被引:4,自引:1,他引:4
Anwar Wagida A.; Salama Somaia I.; Serafy Mostafa M.EI; Hemida Samia A.; Hafez Ahmed S. 《Mutagenesis》1994,9(4):315-317
In this study, we evaluated the effect of low level occupationalexposure of nurses in a medical oncology unit in Cairo, Egypt,to anticancer drugs. Twenty nurses who constantly handled thesedrugs and 20 controls, matched according to age and sex, wereexamined. Metaphase chromosomes were studied. Percentages ofmetaphases with chromosomal aberrations were significantly higher(P < 0.001) in the exposed group (6.1 ± 2.7) versusthe controls (2.6 ± 1.6). The detected chromosomal aberrationswere in the form of chromatid gaps, chromatid breaks and acentricfragments. Micronucleated peripheral blood lymphocytes werealso analyzed in cytochalasin B treated binucleated lymphocytes.There was significant increase in cells with micronuclei (P< 0.001) in nurses (10.05 ± 4.71) in comparison tothe matched control (5.42 ± 2.22) (P < 0.001). Nursesexposed to the cytotoxic drugs for 相似文献