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101.
Does bite-jumping damage the TMJ? A prospective longitudinal clinical and MRI study of Herbst patients 总被引:8,自引:0,他引:8
The aim of this prospective longitudinal study of 62 consecutively treated Class II malocclusions was to determine whether bite-jumping causes temporomandibular disorders (TMD). The function of the temporomandibular joint (TMJ) was assessed anamnestically, clinically, and by means of magnetic resonance images (MRIs) taken before (T1), after (T2), and 1 year after (T3) Herbst treatment. Average treatment time with the Herbst appliance was 7.2 months. In all subjects, Herbst treatment resulted in a Class I or overcorrected Class I dental arch relationship. Thereafter, treatment was continued with a multibracket appliance. The condyle was positioned significantly forward during treatment but returned to its original position after removal of the Herbst appliance. A temporary capsulitis of the inferior stratum of the posterior attachment was induced during treatment. Over the entire observation period from before treatment to 1 year after treatment, bite-jumping with the Herbst appliance: (1) did not result in any muscular TMD; (2) reduced the prevalence of capsulitis and structural condylar bony changes; (3) did not induce disc displacement in subjects with a physiologic pretreatment disc position; (4) resulted in a stable repositioning of the disc in subjects with a pretreatment partial disc displacement with reduction; and (5) could not recapture the disc in subjects with a pretreatment total disc displacement with or without reduction. A pretreatment total disc displacement with or without reduction did not, however, seem to be a contraindication for Herbst treatment. In conclusion, bite-jumping using the Herbst appliance does not have a deleterious effect on TMJ function and does not induce TMD on a short-term basis. 相似文献
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Comparison of radiolabeled nucleoside probes (FIAU, FHBG, and FHPG) for PET imaging of HSV1-tk gene expression. 总被引:18,自引:0,他引:18
Juri Gelovani Tjuvajev Mikhail Doubrovin Timothy Akhurst Shangde Cai Julius Balatoni Mian M Alauddin Ronald Finn William Bornmann Howard Thaler Peter S Conti Ronald G Blasberg 《Journal of nuclear medicine》2002,43(8):1072-1083
The efficacy of 3 radiolabeled probes of current interest for imaging herpes simplex virus type 1 thymidine kinase (HSV1-tk) expression in vivo with PET, including (124)I- or (131)I-labeled 2'-fluoro-2'-deoxy-1-beta-D-arabinofuranosyl-5-iodouracil (FIAU), (18)F-labeled 9-[4-fluoro-3-(hydroxymethyl)butyl]guanine (FHBG), and (18)F-labeled 9-[3-fluoro-1-hydroxy-2-propoxymethyl]guanine (FHPG), was compared. METHODS: Two established rat glioma cell lines, stably transduced RG2TK+ and wild-type RG2, were used for paired comparisons of probe accumulation in vitro and for paired comparisons of subcutaneous xenografts produced from these cell lines in athymic rnu/rnu rats. RESULTS: The in vitro paired probe uptake (0-3 h) comparisons in RG2TK+ cells showed that FIAU accumulation was 15-fold greater than that of FHBG and 41-fold greater than that of FHPG. The net accumulation rate values (+/-SD) calculated for RG2TK+ cells were 0.317 +/- 0.066, 0.022 +/- 0.001, and 0.0077 +/- 0.0003 mL/min/g cells for FIAU, FHBG, and FHPG, respectively. These results and similar uptake studies in RG2 wild-type cells suggest a possible cell membrane transport limitation for FHBG and FHPG. The paired 2-h in vivo uptake studies produced similar differences in RG2TK+ xenografts for FIAU and FHBG (1.22 +/- 0.21 vs. 0.074 +/- 0.49 %dose/g) and for FIAU and FHPG (1.27 +/- 0.14 vs. 0.023 +/- 0.008 %dose/g). These differences were clearly visible on the images. FIAU accumulation at 24 h was 1.53 +/- 0.40 %dose/g. Plasma clearance was FHBG > FHPG > FIAU. The FIAU images showed significant stomach and some intestinal background radioactivities, whereas hepatobiliary and intestinal background activities were very high for the guanosine analogs (FHBG > FHPG). Dynamic imaging showed early ( approximately 10 min) selective localization of FIAU in RG2TK+ xenografts, whereas FHBG and FHPG are being cleared from the HSV1-tk transduced and wild-type xenografts over the initial 2-h imaging period. CONCLUSION: The in vitro and in vivo results (including the PET images) show that FIAU is a substantially more efficient probe than FHBG or FHPG for imaging HSV1-tk expression, with greater sensitivity and contrast as well as lower levels of abdominal background radioactivity at 2 and 24 h. 相似文献
108.
Complex injuries of the distal forearm and the hand by industrial machines often require extensive reconstructive procedures. Crush injuries with soft tissue damage extending over the limits of visible injury require a special approach. Large soft tissue defects often have to be covered by extensive flap procedures. The optimum point of time for plastic reconstruction is an essential question and represents a controversial issue in the literature. To be able to compare different patient cohorts in the future, we classify crush injuries into five clinically relevant categories. In the course of this review article, three different cases of severe crush injuries of the upper extremity are representatively discussed. Two patients were reconstructed in a secondary procedure, one patient in the acute phase. Definite coverage of soft tissue defects in severe crush injuries should be performed secondarily after 5-7 days since the extent of damage in this special form of trauma can often only be judged after a few days and the reconstruction of bones, vessels and tendons is completed. 相似文献
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Immunosuppression and mycobacteria other than Mycobacterium tuberculosis: results from patients with and without HIV infection 总被引:3,自引:0,他引:3
M Peters D Schürmann A C Mayr R Heterzer H D Pohle B Ruf 《Epidemiology and infection》1989,103(2):293-300
Infections caused by mycobacteria other than Mycobacterium tuberculosis (MOTT) have often been described as common in AIDS patients. To evaluate whether infections with MOTT are specific for HIV related immunosuppression or are also frequent in patients with immunosuppression of different aetiology, data on the frequency of isolation from immunosuppressed patients with HIV infection are important. Blood, stool and urine specimens from 134 patients with non-HIV related immunosuppression, and from 55 immunocompetent subjects were examined for mycobacteria. MOTT have been isolated from one immunocompetent person but from none of the immunosuppressed patients. Since in AIDS patients an initial colonization of the gastrointestinal tract (GI-tract) with MOTT is common, GI-tract biopsy specimens from an additional 80 patients were examined microscopically and histologically for mycobacteria. Mycobacteria were not isolated from these specimens. In the same period of time 72 AIDS patients have been examined; 7 (10%) had infections with M. tuberculosis whereas MOTT have been isolated from 16 (22%) of these patients. Mycobacteria have been found only rarely in immunocompetent patients and have not been isolated from patients with non-HIV related immunosuppression. The isolation of MOTT is highly correlated with an HIV-related immunosuppression. 相似文献