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71.
Among 105 tibial shaft aseptic nonunions followed for a mean of 32 months, 30 were treated with dynamic compression plating and 75 were treated with either Küntscher or Grosse-Kempf interlocking intramedullary nailing. With the plating technique, the union rate was 90.0% (27/30), the period of time to union was 5.2 +/- 1.7 months, the complication rate was 16.7% (5/30), the infection rate was 13.3% (4/30), and the surgical time was 110 +/- 30 minutes. With the intramedullary nailing technique, the union rate was 93.3% (70/75), the period of time to union was 5.0 +/- 1.6 months, the complication rate was 17.3% (13/75), the infection rate was 13.3% (10/75), and the surgical time was 70 +/- 30 minutes. Thus, while the union rate was high with both techniques, the complication rate also was high, especially deep infection. However, the technique for nailing was simpler and required less surgical time than plating (p less than 0.001). With open reamed intramedullary nailing, a higher infection rate was noted in the cases initially treated with an external fixator than for cases in which other forms of treatment initially were used (p less than 0.05).  相似文献   
72.
73.
Headspace solid-phase microextraction coupled with gas chromatography/flame ionization detection was developed to measure urinary methyl ethyl ketone (MEK). A fused silica fiber coated with 75 microns carboxen/polydimethylsiloxane was used to extract urinary MEK. The optimal extraction conditions were obtained when temperature was 50 degrees C, extraction time was 15 minutes, and ammonium sulfate concentration was 0.5 g/mL. The optimal desorption temperature and time were 200 degrees C and 5 minutes, respectively. The concentration range of calibration curves was 27 to 8000 ng/mL of MEK. The within-day and between-day pooled coefficients of variation (9 concentrations, triplicate samples) were 5.4% and 8.8%, respectively. The limit of detection and limit of quantitation were 4.2 ng/mL and 21.6 ng/mL, respectively. The recovery (+/- standard deviation) of MEK was 100.2% +/- 8.6% (n = 3). MEK in urine was stable for at least 1 month when stored at -20 degrees C. This method proved to be applicable for the analysis of urinary MEK of exposed workers in a plastic material printing plant. We concluded that this new method is sensitive, inexpensive, simple, and reliable for measuring the occupational exposure of MEK.  相似文献   
74.
The epithelium in kidneys and urinary bladders contain CK18 as in liver cells. The modulation of cytokeratin 18 during tumor transformation in hepatoma had been previously recognized through a series of biochemical and immunological approaches. A 14 KD hepatoma related molecules was found in the previous studies. We would like to utilize the hepatoma transformation model to study the changes in CK18 in transitional cell carcinoma, using immunoblotting and western blotting techniques. The result is that transitional cell carcinoma retain their CK18 molecule. Furthermore, CK18 related molecules similar to those seen in hepatoma also present in transitional cell carcinoma. The conclusions are transitional cell carcinoma contains CK18 related proteins similar to those seen in hepatoma tissues. We suggest that this element would be responsible for the change during the malignant transformation processes.  相似文献   
75.
This study assessed 11C-acetate turnover (clearance) in nasopharyngeal carcinoma (NPC). Data were acquired by dynamic PET after the intravenous injection of 4.625 MBq.kg-1 body weight of 11C-acetate for 30 min. Tomograms were reconstructed and evaluated visually. A time-activity curve of the nasopharynx and neck was generated and the clearance rate of 11C-acetate from the nasopharynx in the slow phase and from NPC was calculated using 0.693/T1/2. Ten patients with nasopharyngeal carcinoma and nine normal subjects were studied. The clearance of 11C-acetate from the normal nasopharynx was rapid and biexponential, in contrast to the rapid uptake followed by extremely slow clearance in patients with NPC. The clearance rate (mean +/- S.D.) was 0.0074 +/- 0.0042 in NPC and 0.0263 +/- 0.0152 in controls in the slow phase, being significantly different between the two groups with no overlap. All nasopharyngeal carcinomas were clearly visualized, in contrast to no obvious retention in the normal nasopharynx. Our initial results indicate that 11C-acetate clearance can be used to differentiate nasopharyngeal carcinoma from a normal nasopharynx. This finding may lead to new applications of 11C-acetate in oncology.  相似文献   
76.
77.
An 83-year-old man with testicular lymphoma demonstrated progressive scrotal enlargement with non-homogeneity sonographically and abnormally increased uptake in the scrotum of Tc-99m HMDP and Tc-99m MIBI scintigraphically. Extensive bone/bone marrow metastases were exhibited by Tc-99m MIBI and Tc-99m HMDP scintigraphies and MRI of the spine. In addition, focal/tubular activity of the femoral bone marrow on Tc-99m MIBI imaging was consistent with skeletal scintigraphic findings. It is emphasized that Tc-99m MIBI total body imaging enabled the demonstration of testicular lymphoma as increased uptake and the illustration of skeletal/bone marrow metastases as diffuse and/or focal increased uptake, especially focal/tubular MIBI activity of the femoral marrow.  相似文献   
78.
This 29-year-old man with cerebral palsy complicated by generalized dystonia was treated by simultaneous bilateral posteroventral pallidotomy. Postoperatively, there was slow, but steady, improvement in the patient's dystonia and disability. However, the improvement in abnormal movements was only prominent for cervical dystonia and oromandibular dyskinesia. The patient's Burke-Fahn-Marsden dystonia scores were 51 preoperatively and 37, 33.5 and 33.5, at 3, 6, and 12 months postoperatively, respectively, demonstrating a maximum improvement of 34%. These results suggest that pallidotomy can be an alternative therapy for those patients suffering from intractable generalized dystonia.  相似文献   
79.
BACKGROUND: Pancreatic serous cystadenoma, mucinous cystic neoplasms, ductal adenocarcinoma with cystic change, and pseudocysts are a spectrum of pancreatic cystic lesions. Their management strategy and prognosis are extremely diverse. Imaging study, cytology, and analysis of the tumor markers of cyst fluid are not always reliable in differentiation of these disease entities. MATERIALS AND METHODS: Fifteen patients with pancreatic cystic neoplasms (including six mucinous cystadenocarcinomas, two mucinous cystic neoplasms with borderline malignancy, two mucinous cystadenomas, and five serous cystadenomas), 4 patients with pancreatic ductal adenocarcinomas with cystic change, and 10 patients with pseudocysts were studied. Echo-guided or computed tomography-guided biopsies of pancreatic cystic lesions and their normal counterparts were conducted on all patients prior to operation or other management. The specimens were assayed for telomerase activity by using TRAP (telomere repeat amplification protocol). The level of telomerase activity in each specimen was semiquantitated as strong, moderate, weak, and none. The final diagnoses were made from histopathological examination of surgically resected or biopsied specimens. The efficacy of telomerase activity as a tumor marker to predict malignancy of pancreatic cystic lesions was evaluated. RESULTS: Three of the four pancreatic ductal adenocarcinomas with cystic change had strong or moderate telomerase activity; four of the six mucinous cystadenocarcinomas had moderate or weak telomerase activity; one of the two mucinous cystadenomas with borderline malignancy had weak telomerase activity; and none of their normal counterparts had detectable telomerase activity. In contrast, none of the two mucinous cystadenomas, five serous cystadenomas, and 10 pseudocysts had detectable telomerase activity. Based on these results, the sensitivity of telomerase activity for prediction of malignancy or premalignancy of pancreatic cystic lesions was 67%, the specificity was 100%, and the positive and negative predictive values were 1.0 and 0.81, respectively. The overall accuracy was 86%. CONCLUSIONS: The differential expressions of telomerase activity have been detected specifically in malignant and premalignant pancreatic cystic tumors, but not in benign cystic neoplasms or pseudocysts. The implications of these results are that telomerase activation takes part in the malignant transformation of pancreatic cystic neoplasms and that telomerase activity is a useful marker to distinguish malignant pancreatic cystic tumors from benign neoplasms and pseudocysts.  相似文献   
80.
The scalp far-field potentials after median nerve stimulation at the wrist consist of P9, P11, P13, and P14 positive components. Earlier, Emerson et al. (1984) identified the "N10" negative potential in-between the P9 and P11 and claimed that this was not merely a passive return to the baseline after the P9 positive deflection but a distinct component reflecting a proximal brachial plexus volley. They thought N10 was a far-field potential having widespread distribution with a fixed latency. In this study we found that N10 was of higher amplitude after median nerve stimulation at the elbow than after stimulation at the wrist. Indeed the N10 latency was fixed from the lower anterior neck to the scalp, and its amplitude was maximum at the anterior lower neck. The latency of N10 was about 0.3 milliseconds longer than the Erb's potential and 0.15 milliseconds longer than the potential recorded from the lateral neck on the side of stimulation. The N10 amplitude increased in parallel with increased stimulus intensity. In order to explore the origin of the N10 stationary field potential, we designed a paired stimuli paradigm applied to the wrist (S1) and to the elbow (S2). The interstimulus interval between S and S2 was adjusted so that the timing of S2 was immediately after the traveling impulse produced by the S1 stimulus as it passed through the S2 stimulus site. This technique allowed stimulation of the anterior interosseous nerve selectively at the elbow while the median nerve originating from the wrist was undergoing refractory period. The response of (S1 + S2) - S1 showed only the N10 with absence of cervical and cortical responses, implying that N10 was activated, predominantly by the interosseous nerve, i.e., an antidromic motor volley, when the median nerve was stimulated at the elbow.  相似文献   
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