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11.
12.
M Cendron K E Whitmore V Carpiniello S J Kurzweil P M Hanno H M Snyder J W Duckett 《The Journal of urology》1990,144(4):987-991
Rupture of the corpus cavernosum is a rare but probably under-reported entity. It truly represents a urological emergency and current recommendations are for early surgical intervention. We review 5 cases with evaluation, treatment and followup. Delays in treatment lead to long-term complications, such as erectile dysfunction and penile curvature. 相似文献
13.
Nitric oxide mediates glutamate-linked enhancement of cGMP levels in the cerebellum. 总被引:74,自引:21,他引:53
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D S Bredt S H Snyder 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(22):9030-9033
Nitric oxide, which mediates influences of numerous neurotransmitters and modulators on vascular smooth muscle and leukocytes, can be formed in the brain from arginine by an enzymatic activity that stoichiometrically generates citrulline. We show that glutamate and related amino acids, such as N-methyl-D-aspartate, markedly stimulate arginine--citrulline transformation in cerebellar slices stoichiometrically with enhancement of cGMP levels. N omega-monomethyl-L-arginine blocks the augmentation both of citrulline and cGMP with identical potencies. Arginine competitively reverses both effects of N omega-monomethyl-L-arginine with the same potencies. Hemoglobin, which complexes nitric oxide, prevents the stimulation by N-methyl-D-aspartate of cGMP levels, and superoxide dismutase, which elevates nitric oxide levels, increases cGMP formation. These data establish that nitric oxide mediates the stimulation by glutamate of cGMP formation. 相似文献
14.
Stephen D. Scoggin M.D. Richard C. Frazee M.D. Samuel K. Snyder M.D. John C. Hendricks M.D. John W. Roberts M.D. Richard E. Symmonds M.D. Randall W. Smith M.D. 《Diseases of the colon and rectum》1993,36(8):747-750
The use of laparoscopic surgical techniques is now being applied to a variety of operations traditionally performed in an open fashion. Twenty patients underwent laparoscopic-guided large and small bowel surgery at our institution from March 1991 to April 1992. The indications for surgery included polyps, obstruction, bleeding, and perforation, and pathologic diagnoses included benign polyps, lipomas, inflammatory bowel disease, perforation of a jejunal diverticulum, colonic arteriovenous malformations, and adenocarcinoma. Mobilization of the colon, ligation of the mesentery, and closure of the mesenteric defect were performed using the laparoscopic equipment. One trocar site was enlarged to 3 cm to deliver the bowel through the abdominal wall. All anastomoses were hand-sewn. Postoperative hospitalization ranged from 2 to 31 days (median, five days). No mortality was noted, and morbidity was 20 percent. We conclude that laparoscopic-guided bowel surgery is technically feasible and should translate into shorter hospitalization and less patient discomfort. 相似文献
15.
In this study, the word retrieval, phonological awareness, sentence completion, and narrative discourse processing skills of 93 reading-disabled and 93 normally achieving subjects from 8 to 14 years of age were compared. The subjects were matched for age, sex, and neighborhood. Results revealed that the two groups differed significantly on the time and accuracy of word retrieval, their ability to produce a syntactically appropriate structure in a sentence completion task, their retelling of stories that had been read to them, their answers to questions about the stories, and their inferences. Further analysis revealed that the variance in the younger reading-disabled children's reading comprehension scores was best accounted for by their performance on the sentence completion and word retrieval measures; the inferencing skills of the older reading-disabled children best accounted for the variance in their reading comprehension. By contrast, the younger normally achieving children's reading comprehension scores were best accounted for by their sentence completion, the proportion of the stories that they retold, and word retrieval scores. The proportion of stories retold and the phonological awareness score of the older normally achieving children best accounted for the variance in their reading scores. These findings suggest that the oral language skills of normally achieving and reading-disabled children may relate differently to their reading comprehension at different age levels. 相似文献
16.
Laura Emmons Patricia Callahan Phyllis Gorman Marcia Snyder 《Journal of Midwifery & Women's Health》1997,42(3):228-253
This article describes the clinical management of dermatologic disorders most commonly encountered in the primary care setting. The common presenting clinical signs and symptoms are reviewed, and the initial laboratory tests that may establish the diagnosis are recommended. Pharmacologic and nonpharmacologic treatments are reviewed. Diagnosis and management of disorders of the sebaceous and apocrine glands, disorders of the hair and pigmentation, fungal, viral, and bacterial infections, dermatitis, and infestations are discussed. A review of the care of skin burns and wounds is included as well as the diagnosis and management of urticaria. 相似文献
17.
Caloric restriction (CR) extends life span and retards the onset of physiological changes and pathologies associated with aging, but the underlying mechanisms remain unresolved. This study demonstrates that CR postpones the documented age-related declines in and/or enhances the activity and microsomal concentration of several liver monooxygenases in male rats, i.e., NADPH cytochrome P-450 reductase, total cytochromes P-450. However, the relative concentration of cytochrome P-450b+C did not exhibit statistically significant changes, whereas another isozyme, the male specific P-450h, declined significantly in both ad libitum-fed and CR rats as a function of increasing age. While CR appears to retard age-associated changes in certain liver enzymes, this effect is by no means universal. The hepatic monooxygenases constitute a well-characterized enzyme system in which to examine the perturbation of the aging process by CR. 相似文献
18.
MR imaging of cerebral dural sinus thrombosis 总被引:1,自引:0,他引:1
19.
Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
20.
A C Snyder 《American journal of optometry and physiological optics》1987,64(2):104-109
Traditionally changes in corneal thickness associated with contact lens wear have been measured with optical pachometers after the lenses are removed from the cornea. In studies of corneal response to the extended wearing of hydrogel and silicone elastomer contact lenses, optical pachometry measurements may be improved by uninterrupted lens wear during the measurements. Using four flexible lens types differing in design and thickness, a single observer made pachometric measurements both with and without the lenses in place on eight subjects. This study demonstrates that valid and reliable measures of corneal thickness may be made without removing flexible lenses from the eye. 相似文献