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991.
Leiomyosarcoma of the mesentery is a rare neoplasm. The clinical manifestation is non-specific and preoperative diagnosis is often late. Mitotic activity shows no significant correlation with the biological behavior of neoplasm. The surgical excision is the therapy of choice but local recurrence is high. The authors report a case of leiomyosarcoma which was treated by surgical removal and underline the diagnostic difficulties.  相似文献   
992.
993.
994.
The authors present anin vivo phosphorus magnetic resonance spectroscopy systematic study on the effects of cytosolic pH on skeletal muscle mitochondrial respiration in human calf muscle. In 49 normal subjects, the effect of cytosolic pH on kinetics of phosphocreatine and adenosine diphosphate recovery and on maximum rate of mitochondrial adenosine triphosphate production (Qmax) was evaluation. The results show a strong relationship between the rate of postexercise phosphocreatine recovery and the lowest value of cytosolic pH reached during recovery from exercise (termed minimum pH;r=0.89); in constrast, both adenosine diphosphate recovery halftime andQ max were independent of cytosolic pH at the end of exercise.  相似文献   
995.
A simple assay format was developed for the direct detection of C. trachomatis rRNA utilizing ligation of recombinant MDV-1 probe RNA fragments hybridized to 23S rRNA after capture and release from a solid support. Assay background (equivalent to 10(4) targets) was suppressed by blocking sequences in the 5' MDV reporter probe fragment complementary to the 3' fragment by prehybridization of a DNA oligonucleotide. A pair of reporter fragments bearing a deletion within the region, obtained by a hydrid-selection-amplification protocol, yielded a low level of assay background which was reduced to < 2% with a blocker directed against the remaining pairing sequence. This probe set showed a sensitivity of 10(3) molecules of 23S rRNA (> 95% responding) and could detect a single elementary body (EB) of Chlamydia trachomatis or 1-10 EB added to a clinical matrix of pooled negative human cervical swab samples. The time of first appearance of amplification products by real-time fluorescence detection showed a linear response to log increases in the target level over a 10(5)-fold range, permitting the determination of target level within an order of magnitude. The assay showed approximately 10(9)-fold discrimination over Chlamydia pneumonae (TWAR) rRNA. High levels of cultured C. albicans, E. coli, S. aureus, or N. gonorrhoeae had no detectable effect on assay background or the ability to detect a single elementary body.  相似文献   
996.
756 smokers were randomly assigned by stage of change to (1) standardized self-help manuals (ALA+ condition), (2) individualized manuals matched to stage (TTT condition), (3) interactive expert-system computer reports plus individualized manuals (ITT condition), or (4) a personalized condition with 4 counselor calls, stage manuals, and computer reports. Over 18 mo, the ITT group's results more than doubled those of the ALA+ group on abstinence measures. The ALA+ and TTT conditions were equivalent over 12 mo, but at 18 mo the TTT condition was more effective. The ITT condition was the best or comparable with the best treatment at all follow-ups for smokers at all stages of change. Results suggest that an effective expert system has been developed, and discussion focuses on delivering this system to entire populations of smokers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
998.
Surgery--namely, suture closure-is still the treatment of choice for perforated peptic ulcers, despite the proven efficacy of Taylor's conservative approach. Such conservative management, however, has been proven less effective in high-risk patients and those with perforations more than 12 h old. Here we suggest alternative laparoscopic treatments for perforated peptic ulcers. We have treated laparoscopically six patients (one F, five M; mean age 57.6 years; range 31-81 years); the mean duration of the operation was 52 min; the median hospital stay was 7 days (6-15 days); H2-blockers, antibiotics, and fluids were administered in the p.o. course; the follow-ups range from 6 to 18 months. On the basis of our experience, the treatment of choice for perforated peptic ulcers is Taylor's conservative procedure and laparoscopic drainage of the abdominal cavity when there is mild peritoneal reaction (usually less than 6 h from the onset of perforation). In case of remarkable peritonitis (usually more than 12 h), it is mandatory to add an accurate lavage. When the site of perforation is concealed by the peritoneal inflammation it should not be searched; when visible, it might be obliterated with the round ligament or an omental tissue strand, particularly if larger than 1 cm in diameter.  相似文献   
999.
This investigation was performed to study atrial systolic function is response to modification of atrioventricular delay in a sample of 36 patients with a DDD pacemaker implanted for complete atrioventricular block. The relation between atrial systolic performance and diastolic-related parameters was also evaluated. Isovolumic relaxation time, early diastolic peak velocity, late (atrial) diastolic peak velocity, atrial filing fraction, and atrial ejection force were recorded at a pacing rate of 70 impulses/min and at atrioventricular delay of 200, 150, and 100 msec. Our data showed that the progressive shortening of atrioventricular delay induced a gradual increase in early peak velocity (median value 46 to 53 to 61.5 cm/sec, respectively, at 200, 150, and 100 msec intervals) and a gradual decrease in isovolumic relaxation time (median 92.6 to 81.5 to 69.7 msec at 200, 150, and 100 msec, respectively), atrial peak velocity (59 to 52 to 44.5 cm/sec at 200, 150, and 100 msec, respectively), atrial filling fraction (50.5% to 40% to 23.5% at 200, 150, and 100 msec, respectively), and atrial ejection force (17.2 to 14.7 to 8.5 kilodynes at 200, 150, and 100 msec, respectively). For every atrioventricular delay value detected, we found a significant correlation between isovolumic relaxation time and early peak velocity with atrial filling fraction and atrial ejection force. In addition, atrial ejection force was related directly to atrial filling fraction at studied atrioventricular delays. The two indexes of atrial systolic performance showed a parallel decrease by shortening the atrioventricular delay, and they can quantify atrial systolic performance equally in sequentially paced patients. Furthermore, our results are in accordance with the hypothesis that the interaction between the effectiveness of active left atrial emptying and isovolumetric relaxation time may play an important role in maintaining an ideal ventricular filling despite changes in atrial systolic function.  相似文献   
1000.
Several aspects of the analysis of the data obtained with the cryogenic heat-and-ionization Ge detectors used by the EDELWEISS dark matter search experiment are presented. Their calibration, the determination of their energy threshold, fiducial volume and nuclear recoil acceptance are detailed.  相似文献   
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