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991.
992.
Forty-five caries-free primary molars from children with continuous fluoride supplementation (n = 28) after birth and from children without fluoride prophylaxis (n = 17) were investigated by light microscopy. The following results were obtained: The prophylaxis group evidenced a special form of calcification consisting of fibrodentin-like hard tissue developing intramurally in the dentin wall especially at the pulp floor and spreading irregularily into the pulp cavity by displacing the degenerating pulp tissue (n = 24). These teeth were ankylosed in the bi- and trifurcation area as well as inside the roots. This kind of hard tissue was not observed in the teeth from untreated children. Only 5 children had greater calcifications attached at the pulp wall. Nevertheless, this difference was statistically significant (p = 0.001) and indicates a relationship between fluoride prophylaxis, the special form of pulp calcification and tooth ankylosis.  相似文献   
993.
The aim of GH replacement therapy in GH-deficient adults is to optimize response with minimum incidence of adverse reactions, but optimal therapy regimens are still to be established. This two-arm parallel study examined effects of two GH dose algorithms in adults with GH deficiency of adult or childhood onset. Patients on low dose (LD; n = 302) received GH at 3 microg/kg per day for 3 months increasing to 6 microg/kg per day for 3 months, and those on conventional dose (CD; n = 293) started on 6 microg/kg per day for 3 months increasing to 12 microg/kg per day for 3 months. The proportion of patients completing therapy was greater for the LD group than the CD group for the first 3 months (93.0% vs. 88.1%; P = 0.037) and overall for the 6 months (90.7% vs. 84.0%; P = 0.013). Both dose groups showed significant increases in lean body mass and decreases in fat mass for all time points. Percent increase in lean body mass was less with LD than CD over the first 3 months (2.43 +/- 4.33 vs. 3.58 +/- 4.69%; P = 0.006) but not overall for the 6-month period (4.38% +/- 5.34% vs. 5.21% +/- 5.99%; P = 0.141). Percent decrease in fat mass was less with LD than CD for the first 3 months (-2.81% +/- 7.81% vs. -5.53% +/- 8.64%; P < 0.001) and overall for the 6-month period (-6.35% +/- 9.42% vs. -9.45% +/- 12.07%; P = 0.006). IGF-I SD score increased less with LD than CD for 0 to 3 and 0 to 6 months, although for IGF-binding protein-3 SD score, there was no significant difference between doses at any time. Arthralgia was the only adverse event that occurred significantly less frequently with LD than with CD. Calculated changes based on gender and onset indicated greater changes in males than females for body composition, but there was little difference in GH-related adverse events between males and females. The lower starting dose with dose titration appeared more favorable, but differences in response between genders and onset of GH deficiency need to be taken into account when setting an individual dose regimen.  相似文献   
994.
995.
AIM OF THE STUDY: According to the literature, atraumatic shoulder dislocations occur without or only minor trauma,self-reduction and no or little pain.Little is known about intraarticular pathology in this entity.It was the purpose of our study to evaluate such findings. METHODS: During a 2-year period,226 patients had surgery for shoulder dislocation.28 patients met the criteria for atraumatic dislocation as above (group A).Patients with bony pathology or recurrent microtrauma were excluded. All had been treated with a rehabilitation program without success.28 consecutive patients with surgery after posttraumatic dislocation served as a control group (group B). At the beginning of the surgery,arthroscopy was performed in all patients and the intraarticular findings were recorded.For the capsulo-labral pathology,we determined 3 types: type I had capsular elongation or scarring and included so called "non-Bankart-lesions"; type II had classic "Bankart"-lesions and type III more complex capsulo-labral lesions like e.g. "ALSPA"-lesions. RESULTS: The mean age in group A was 27.6 y and 26.2 y in group B.12 patients in group A and 5 in group B were female.The average no.of dislocations was 10 (1-30) or 9 (1-28), respectively.In group A we saw type I lesions in 11 patients (39.3%), type II lesions in 9 (32.1%) and type III lesions in 8 (28.6%) patients. In group B we found type I lesions in 8 (28.6%), type II lesions in 4 (14.3%) and type III lesions in 16 (57.1%) patients.Hill-Sachs lesions were found in 22 (78.6%) and 23 (82.1%) of the patients, respectively.Also, we saw chondral glenoid damage, cuff lesions and SLAP-lesions in both groups. CONCLUSION: The above mentioned criteria for atraumatic shoulder dislocation do not exclude intraarticular pathology comparable to posttraumatic cases, at least for patients, who do not respond to a conservative treatment. Besides the etiology, the given pathology must be considered for therapy.  相似文献   
996.
997.
998.
OBJECTIVE: The aim of this study was to determine the accuracy of CT arterioportography and hepatic digital subtraction angiography, separately and combined, for the detection of hepatocellular carcinoma in the cirrhotic liver by using thin-section liver explant histopathologic findings. SUBJECTS AND METHODS: Fifty-nine patients with liver cirrhosis were examined with CT arterioportography and digital subtraction angiography as a part of preoperative diagnostic workup for liver transplantation. Before liver explantation, CT arterioportograms and digital subtraction angiograms were prospectively evaluated in a blinded manner, separately by two CT radiologists and two angiographers, respectively, and combined by two reviewer teams, each including a CT radiologist and an angiographer. In addition, each examination was retrospectively evaluated using direct comparison with the corresponding thin-section liver explant specimens RESULTS: There were 39 histologically confirmed hepatocellular carcinomas. In both prospective and retrospective assessments, the reviewers achieved the best performance with CT arterioportography and digital subtraction angiography combined (area under the curve [A(z)] 0.82). The diagnostic confidence in the detection of hepatocellular carcinoma was higher with digital subtraction angiography (A(z), 0.81) than that with CT arterioportography (A(z), 0.68). Prospectively, sensitivity and specificity were 75% and 60% for CT arterioportography, 77% and 80% for digital subtraction angiography, and 84% and 81% for CT arterioportography and digital subtraction angiography combined, respectively. Retrospectively, sensitivity and specificity were 80% and 62% for CT arterioportography; 82% and 79% for digital subtraction angiography; 87% and 81% for CT arterioportography and digital subtraction angiography combined, respectively. Five hepatocellular carcinomas, one poorly and four well differentiated, with a mean size of 1.4 cm were not detectable on the CT arterioportography and digital subtraction angiography combination. False-positive findings were 20, 11, and 10 on CT arterioportography, digital subtraction angiography, and the CT arterioportography and digital subtraction angiography combination. CONCLUSION: Combining CT arterioportography with digital subtraction angiography enabled reliable detectability of moderately and poorly differentiated hepatocellular carcinomas in cirrhotic livers but was less sensitive for the detection of well-differentiated hepatocellular carcinomas and resulted in a relatively high rate of false-positive findings.  相似文献   
999.
BACKGROUND: Experimental studies suggest that surgical injury may up- or down-regulate nociceptive function. Therefore, the aim of this clinical study was to evaluate the effect of elective arthroscopically assisted knee surgery on nociceptive responses to a heat injury. METHODS: Seventeen patients scheduled to undergo repair of the anterior cruciate ligament and 16 healthy controls were studied. The first burn injury was induced 6 days before surgery, and the second burn was induced 1 day after surgery with a contact thermode (12.5 cm2, 47 degrees C for 7 min) placed on the medial aspect of the calf contralateral to the surgical side. Ibuprofen and acetaminophen were given for 2 days before the first burn injury and again from the time of surgery. In the controls, the two burn injuries were separated by 7 days. Sensory variables included cumulated pain score during induction of the burn (visual analog scale), secondary hyperalgesia area, and mechanical and thermal pain perception and pain thresholds assessed before and 1 h after the burn injury. RESULTS: The heat injuries induced significant increases in pain perception (P < 0.001) and decreases in pain thresholds (P < 0.02). Baseline heat pain thresholds were higher during the second burn injury in patients (P < 0.001) and controls (P < 0.01). However, there were no significant differences in pain to heat injury (P > 0.8), secondary hyperalgesia areas (P > 0.1), mechanical and thermal pain perception (P > 0.1), or mechanical and thermal pain thresholds (P > 0.08) in the burn area before surgery compared to after surgery. CONCLUSION: Arthroscopic knee surgery did not modify nociceptive responses to a contralaterally applied experimental burn injury.  相似文献   
1000.
BACKGROUND AND OBJECTIVES: Due to the increased popularity of laryngeal laser therapy, surgeons and anesthesiologists are inevitably confronted with questions concerning the choice of the most efficient endotracheal tube (ETT) for laryngeal laser surgery, especially with regard to possible endolaryngeal tube fires, or combustions. The purpose of this study was to determine the current practice in endolaryngeal laser surgery in Germany. STUDY DESIGN/MATERIALS AND METHODS: A questionnaire was sent to 152 ENT Departments in Germany, care was taken that the responders could send back the questionnaire anonymously. Among other questions the participants were asked for the number of lasersurgical treatments of the larynx performed in the past, the usual type of ETTs in use, whether other safety precautions were taken during CO2 laser surgery of the larynx and for intraoperative complications like tube ignition, fires or combustions. RESULTS: Eighty six of the 152 addressed ENT departments replied. In laryngeal laser surgery, 59/86 departments regularly use special laser tubes in daily routine (74.5%). In about 20,000 lasersurgical procedures, 15 incidents of ETT fire have been reported. In six of the reported 15 cases a tube fire occurred despite the fact that special laser tubes had been utilized. CONCLUSIONS: The present study could demonstrate that the use of special laser tubes does not necessarily protect against ETT fire. Thus, even when using special laser tubes other safety measures should be taken. In view of the maximum safety for the patient it has to be stated, that the safety during surgery correlates definitely with the experience of the surgeon. The weakest point of ETTs is usually situated in the cuff region.  相似文献   
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