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991.
992.
In recent years, the popularity of intramedullary humeral nailing is on the rise in spite of its handicaps. There are many problems in intramedullary humeral stabilization because of the anatomic structure of the bone. We performed various methods and measurements to determine shape, length and diameter and curvature of the medullary canal of the humerus in 57 human dry cadaver bones. Anterior angulation with an average of 21 cm apart from greater tubercle was found at 1/3 distal part. Mean degree of angulation was 9 degrees (max: 15, minutes: 5, S.D.: 2.84). Humerus bones with septal aperture (supratrochlear foramen) at the fossa coronoidea were observed to have very narrow medullary canal. The best point for nail insertion was found to be an area on the line from greater tubercle anteromedially to caput humeri. This study revealed that carefully evaluated structure of humeral medullary canal and various congenital constructions such as septal aperture, and correct selection of a nail with proper length and diameter are essential for successful nailing.  相似文献   
993.
The interaction between the renin-angiotensin system and nitric oxide (NO) is undeniable, but its nature is not fully known. This study investigated the contribution of NO to the acute hypotensive effect of captopril in conscious normotensive rats and the effect on blood pressure of dual administration of captopril and the phosphodiesterase-5 inhibitor zaprinast. In two separate experiments, rats were pretreated with the NO inhibitor L-arginine methyl ester (L-NAME) and with the NO enhancer zaprinast. Pretreatment with L-NAME attenuated and pretreatment with zaprinast potentiated the hypotensive effect of captopril. The hypotensive effect of captoril was not associated with a significant change in the plasma level of cyclic guanosine monophosphate (cGMP). These findings suggest that NO contributes to the blood pressure-lowering effect of captopril. The inability of captopril to alter plasma cGMP levels is not consistent with this view, however, and leads to the conclusion that NO contributes to the acute hypotensive effect of captopril, although the mechanism is not fully understood. Zaprinast potentiates the hypotensive effect of captopril, and an adjustment in dose should be considered when this combination is administered.  相似文献   
994.
Esophageal ulceration complicating doxycycline therapy   总被引:2,自引:1,他引:1  
AIM: To report present state of iatrogenic drug-induced esophageal injury (DIEI) induced by medications in a private clinic. METHODS: Iatrogenic drug-induced esophageal injury (DIEI) induced by medications has been more frequently reported. In a private clinic we encountered 36 cases of esophageal ulcerations complicating doxycycline therapy in a mainly younger Saudi population (median age 29 years). RESULTS: The most frequent presenting symptoms were odynophagia, retrosternal burning pain and dysphagia (94 %, 75 % and 56 %, respectively). The diagnosis was according to medical history and confirmed by endoscopy in all patients. Beside withdrawal of doxycycline, when feasible, all patients were treated with a proton-pump inhibitor (PPI) and a prokinetic. Thirty patients who reported to the clinic after treatment were improved within 1-7 (median 1.7) days. CONCLUSION: Esophageal ulceration has to be suspected in younger patients with odynophagia, retrosternal burning pain and/or dysphagia during the treatment with doxycycline.  相似文献   
995.
Gene-expression profile of collagen-induced arthritis   总被引:6,自引:0,他引:6  
  相似文献   
996.
BACKGROUND: Increased mortality rates have been reported after high titer measles [>10(5.0) plaque-forming units (PFU)] vaccination in several large studies in the developing world. An increased titer measles vaccine study conducted in Sudan included a prolonged prospective evaluation of childhood morbidity after vaccination. METHODS: Five hundred ten children (170 per group) were randomized to receive 1 of 3 regimens at 5 and 9 months of age: (1) meningococcal vaccine, then standard titer (50% tissue culture-infective dose, 103.8) Schwarz measles vaccine; (2) increased titer (10(4.7) PFU) Edmonston-Zagreb measles vaccine followed by meningococcal vaccine; and (3) increased titer (10(4.7) PFU) Connaught vaccine followed by standard titer Schwarz measles vaccine. RESULTS: Health workers collected information at 31,582 semi-monthly and monthly visits during 5 years. No increase in infant mortality was observed, but the statistical power was limited. There were 13, 13 and 10 deaths in the Schwarz, Edmonston-Zagreb and Connaught groups, respectively. There were no differences in duration or incidence of illness between groups at any time during the 5-year follow-up, with comparisons stratified by age and sex. Statistical power for each pairwise comparison was good, with at least 80% power to detect a difference of 1 day per month of illness and a 12% difference in the proportion of visits with an illness recorded. CONCLUSIONS: We were unable to document increased morbidity in recipients of the increased titer measles vaccines used in this study. These data do not support the hypothesis that increased mortality after increased titer vaccine exposure is the result of increased and cumulative morbidity.  相似文献   
997.
BACKGROUND: To determine if the distribution of prognostic factors accounted for the differences when the outcome for localised Ewing Sarcoma/PNET bone in Saudi Arabia was compared with results from countries with well developed health care systems. PROCEDURE: Retrospective analysis was undertaken of 163 consecutive patients of all ages, treated with radical intent at KFSHRC from 1975 to 1998. Standard chemotherapy was commenced in all patients. The local treatment modality was resection +/- radiation in 30% and radiation treatment alone in 67%. Size data were available for 51 patients treated from 1994 to 1998, inclusive. One third of these patients had tumors with volume >500 ml. RESULTS: Three year survival significantly increased with the year of diagnosis, 1975-1988 45%; 1989-1993 55%; and 1993-1998 63% (P = 0.006). Favorable prognostic factors were age < or =14 (P = 0.07); site, distal extremity, and skull (P = 0.08); and volume < or = 200 ml (P = 0.06). Secondary prognostic factors were response to induction chemotherapy, both histological, 100% necrosis, (P = 0.04) and clinical CR+PR, (P = 0.02). From 1994 to 1998, 3 year survival for tumors in the distal extremity and skull was 80% and for small tumors, < 200 ml, at any site was 82%. In comparison, the 3 year survival for patients with tumors at any other sites was 60%, and for tumors >200 ml, 55%. CONCLUSIONS: Overall survival progressively improved. From 1994 to 1998 the survival of patients with small tumors and/or favorable sites was similar to the best reported results. It was not possible to compare results by tumor size for large tumors, > 500 ml, due to the absence of data from elsewhere. A better staging system is required for the international comparison of results.  相似文献   
998.
A history of cardiac auscultation and some of its contributors   总被引:1,自引:0,他引:1  
Before the 19th century, physicians could listen to the heart only by applying their ear directly to the chest. This “immediate auscultation” suffered from social and technical limitations, which resulted in its disfavor. With the invention of the stethoscope by Laennec in 1816, “mediate auscultation” became possible, introducing an exciting and practical new method of bedside examination. Over the past 2 centuries, many illustrious physicians have contributed to the understanding of cardiac auscultation by providing an explanation for the sounds and noises that are heard in the normal and diseased heart. This article traces the lives and achievements of those who have contributed importantly to cardiac auscultation. Auscultation remains a low cost, but still sophisticated procedure that intimately connects the physician to the patient and transfers that all-important clinical power known as “the laying on of the hands.” When used with skill, it may correctly determine whether more expensive testing should be ordered. In this way, the stethoscope deserves our continued respect and more attention as an indispensable aid for the evaluation of our patients.  相似文献   
999.
1000.
The aims of this study were to assess whether the increased oxidative stress in affected tissues is reflected by serum lipid peroxidation and to check for alterations in serum levels of extracellular antioxidants and antioxidant enzyme activities in patients with Behcet's disease (BD). Serum malondialdehyde (MDA) and ceruloplasmin (Cp) levels and CuZn-superoxide dismutase (CuZn-SOD) and glutathione peroxidase (GSH-Px) activities were increased, while serum transferrin (Trf) levels were diminished in patients with active ocular BD (n = 19), inactive ocular BD (n=18), and nonocular BD (n=15), compared to healthy controls (n = 20). Serum MDA levels in patients with active ocular BD and nonocular BD were significantly higher than in the inactive ocular BD group. Patients with active ocular BD also had significantly higher serum Cu-Zn SOD activities, compared to the inactive ocular BD. Erythrocyte sedimentation rate (ESR) and serum C-reactive protein (CRP) levels were higher in patients with active ocular BD, inactive ocular BD, and nonocular BD, compared to the control group. In addition, patients with active ocular BD and nonocular BD had significantly higher ESR and serum CRP levels, compared to the inactive ocular BD group. Serum albumin concentrations showed no significant differences among the BD patients and controls. The authors speculate that in BD patients, serum superoxide radicals may be dismutated to H2O2 by increased CuZn-SOD activity and the conversion of H2O2 to hydroxyl radical may be enhanced by iron, owing to diminished serum Trf; these mechanisms may contribute to the increased serum lipid peroxidation.  相似文献   
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