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111.
Pharmaceutical Chemistry Journal - Commonly flavonoids are the natural components found in vegetables, spices and colored fruits. Flavonoids include a large group of polyphenolic compounds, namely...  相似文献   
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113.
We present the case of a 70-year-old man diagnosed with Mycobacterium abscessus pulmonary infection complicated with rheumatoid arthritis who was treated with corticosteroids. He died despite treatment according to the recommended regimen of imipenem, clarithromycin, and amikacin. Autopsy revealed granulomatous lesions throughout the bilateral lungs. We conclude that M. abscessus infection may have a fatal outcome because of the drug resistance of the pathogen. This case suggests that rheumatoid arthritis might be a risk factor for M. abscessus pulmonary infection, but further studies are necessary for clarification.  相似文献   
114.
GOALS: To determine the significance of performing routine duodenal biopsies during upper intestinal endoscopy in a pediatric population and to evaluate their contribution to the overall diagnosis. BACKGROUND: Performing duodenal biopsy during every upper endoscopy regardless of the indication for endoscopy and the macroscopic findings, is a controversial topic. Advocates of performing routine biopsies argue that unexpected pathology such as villous atrophy, may have significant clinical implications. Opponents argue that the yield of performing a biopsy on an apparently normal mucosa is low. STUDY: Duodenal biopsies, routinely taken from 201 pediatric patients during upper endoscopy over a 26-month period were retrospectively reviewed. Duodenal biopsies taken during this period for suspected mucosal lesions were not included in the analysis. Indications for endoscopy included suspected peptic disease, gastroesophageal reflux, unexplained vomiting, abdominal pain, iron deficiency anemia and Crohn disease. RESULTS: Of the 201 sets of biopsies reviewed, 159 (79.1%) were normal, 7 had insufficient material for evaluation and 35 (17.4%) carried abnormalities that included: 10 Giardia lamblia (4.9%), 13 mild chronic inflammation (6.5%), and 8 increased intraepithelial lymphocytes (3.9%). Two biopsies showed mixed acute and chronic inflammation, 1 showed lymphatic dilatation and 1 had a mild mucosal lesion. The risk for microscopic pathology in the duodenum was higher when Helicobacter pylori was present in the gastric biopsy (25.98% vs. 12.16% P < 0.02). The negative predictive value of a normal appearing duodenal mucosa was 81.5%, implying that a normal appearing mucosa does not rule out pathology. No complications were encountered in our series. CONCLUSION: We suggest that the inclusion of routine duodenal biopsies as part of upper endoscopy in pediatric patients should be considered favorably. This practice may yield additional pathologic findings that otherwise could have been missed. It should be done regardless of the indication for endoscopy or the gross appearance of the mucosa. This practice does not increase the risk of the procedure.  相似文献   
115.

Background

Pressure immobilization bandages delay mortality for 8 hours after coral snake envenomation, but long-term efficacy has not been established.

Objective

The objective of this study is to determine the long-term efficacy of pressure immobilization bandages after coral snake envenomation in the absence of antivenom therapy.

Methods

A randomized, observational pilot study was conducted. Ten pigs (17.3-25.6 kg) were sedated, intubated for 5 hours, and injected subcutaneously with 10 mg of lyophilized Micrurus fulvius venom resuspended in water. Pigs were randomly assigned to a control group (no treatment) or a treatment group (compression bandage and splint) approximately 1 minute after envenomation. Bandage pressure was not controlled. Pigs were monitored daily for 21 days for signs of respiratory depression, decreased oxygen saturations, and paralysis. In case of respiratory depression, pigs were humanely euthanized and time to death recorded. Statistical analysis was performed with Fisher exact test, Mann-Whitney U test, and Kaplan-Meier survival curve as appropriate.

Results

Median survival time of control animals was 307 minutes compared with 1172 minutes in treated animals (P = .10). Sixty percent of pigs in the treatment group survived to 24 hours vs 0% of control pigs (P = .08). Two of the treatment pigs survived to the end point of 21 days but showed necrosis of the distal lower extremity.

Conclusions

Long-term survival after coral snake envenomation is possible in the absence of antivenom with the use of pressure immobilization bandages. The applied pressure of the bandage is critical to allowing survival without necrosis. Future studies should be designed to accurately monitor the pressures applied.  相似文献   
116.

Introduction

Proton radiation offers physical advantages over conventional radiation. Radiosensitivity of human 59M ovarian cancer and HTB140 melanoma cells was investigated after exposure to γ-rays and protons.

Material and methods

Irradiations were performed in the middle of a 62 MeV therapeutic proton spread out Bragg peak with doses ranging from 2 to 16 Gy. The mean energy of protons was 34.88 ±2.15 MeV, corresponding to the linear energy transfer of 4.7 ±0.2 keV/µm. Irradiations with γ-rays were performed using the same doses. Viability, proliferation and survival were assessed 7 days after both types of irradiation while analyses of cell cycle and apoptosis were performed 48 h after irradiation.

Results

Results showed that γ-rays and protons reduced the number of viable cells for both cell lines, with stronger inactivation achieved after irradiation with protons. Surviving fractions for 59M were 0.91 ±0.01 for γ-rays and 0.81 ±0.01 for protons, while those for HTB140 cells were 0.93 ±0.01 for γ-rays and 0.86 ±0.01 for protons. Relative biological effectiveness of protons, being 2.47 ±0.22 for 59M and 2.08 ±0.36 for HTB140, indicated that protons provoked better cell elimination than γ-rays. After proton irradiation proliferation capacity of the two cell lines was slightly higher as compared to γ-rays. Proliferation was higher for 59M than for HTB140 cells after both types of irradiation. Induction of apoptosis and G2 arrest detected after proton irradiation were more prominent in 59M cells.

Conclusions

The obtained results suggest that protons exert better antitumour effects on ovarian carcinoma and melanoma cells than γ-rays. The dissimilar response of these cells to radiation is related to their different features.  相似文献   
117.
Fifty-one patients undergoing total repair of tetralogy of Fallot between November 1977 and June 1985 were analyzed with respect to determinants of operative mortality and postoperative right to left ventricular peak systolic pressure ratio (RV/LV). The risk factors were age, sex (Sex), previous shunting operation (Shunt), extent of right ventricular outflow tract patch (Patch), various PA-indexes, maximal left atrial volume/BSA (LA/BSA), left ventricular end diastolic volume index (LVEDVI), LVEDVI/normal-LVEDVI, RV/LV, Hb, BSA and weight. Univariate analysis indicated that RV/LV and LA/BSA were associated with operative death. A model for operative mortality with three variables emerged from the multiple stepwise regression analysis: Patch, Shunt and Sex (R = 0.421, R2 = 0.177, F = 3.37). A model for predicted RV/LV with five variables: Weight, Shunt, BSA, Patch and Sex (R = 0.602, R2 = 0.363, F = 5.12). However, it was thought difficult to predict operative mortality and postoperative RV/LV by the preoperative variables. Intra- and postoperative factors might have larger influences on operative mortality and RV/LV than the preoperative ones.  相似文献   
118.
CT-guided nerve root block and ablation   总被引:1,自引:0,他引:1  
We report our experience in performing 52 CT-guided peripheral nerve root blocks and 27 CT-guided nerve root ablations. The nerve root block procedures were performed as diagnostic tests to determine the clinical significance of equivocal herniated disk or foraminal stenosis (n = 33) and before nerve root ablations (n = 19). To evaluate the clinical significance of these nerve root blocks, we performed 52 procedures at the vertebral level where a herniated disk or foraminal stenosis had been identified on CT or MR images. In 51 of 52 cases, the procedures were successful in anesthetizing the intended nerve root, which allowed us to determine whether that particular nerve root was the source of pain. By relieving or not relieving pain, the results of the diagnostic nerve root blocks helped determine whether a protrusion or foraminal stenosis was clinically significant. The nerve root ablations were done exclusively for treatment of pain in patients with malignant disease. Significant relief of pain was obtained in 17 (63%) of 27 patients. The thoracic nerve ablations were the most successful (9/10 or 90%) because the correct thoracic nerve innervation to the offending lesion could be identified. The lumbosacral nerve ablation procedures were the least successful (6/14 or 43%) because the innervation of the pelvic neoplasms was complex, arising from multiple lumbosacral nerves that often were bilateral. Equivocal foraminal stenosis and disk protrusion are common findings on CT and MR imaging, and CT-guided nerve block procedures can help determine which of these findings are clinically significant. CT-guided nerve root ablations have limited efficacy but can help control pain in patients with a malignant disease, especially when the pain is in the distribution of a thoracic nerve dermatome.  相似文献   
119.
120.
N. Fujitsuka  A.A. Kori  M. Sokabe  F. Ito   《Brain research》1988,443(1-2):243-253
A preparation of decapsulated muscle spindles with intact sensory innervation has been developed to allow direct access to the sensory terminal for the application of drugs or to alter the extracellular ionic composition. Muscle spindles were isolated from semitendinosus muscles of the frog Rana catesbeiana, and were incubated in a calcium-free Ringer's solution containing 0.2% collagenase. Following optimal incubation at 34 degrees C for 30 min the response pattern of the spindles during stretch could not be distinguished from that of intact spindles, although the duration of individual afferent spikes was prolonged about 4 times normal. The spikes disappeared immediately after the Ringer's solution was replaced with an isotonic choline chloride solution, in contrast to those of intact spindles which remained for 30 min after the replacement. Electron microscopy showed that the outer and inner capsules were partially disrupted. No significant change was observed in the size or packing density of intramembrane particles in freeze-fracture replicas of spindles decapsulated under optimum conditions. More prolonged treatment with the enzyme resulted in abolition of the static component of the response during stretch, and also in an aggregation of the particles, whose size decreased and packing density increased.  相似文献   
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