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By using stereotaxic surgical techniques, ventral mesencephalic tissues from aborted human fetuses of 8 to 10 weeks' gestational age were implanted unilaterally into the striata in two patients with advanced Parkinson's disease. The patients were treated with a cyclosporine, azathioprine, and steroid regimen to minimize the risk for graft rejection. They were examined for 6 months preoperatively and 6 months postoperatively and continued to receive the same doses of antiparkinsonian medication. There were no significant postoperative complications. No major therapeutic effect from the operation was observed. However, in the clinical tests, both patients showed small but significant increases of movement speed for repeated pronation-supination, fist clenching, and foot lifting. The rate of walking also increased in the one patient tested. For both patients, there was an initial worsening postoperatively, followed by improvement vs preoperative performance at 1 to 3 months. Both patients also showed significant improvement in the magnitude of response to a single dose of levodopa (L-dopa), but there was no increase in the duration of drug action. The motor readiness potential increased in both patients postoperatively, primarily over the operated hemisphere. Neurophysiological measurements also showed a more rapid performance of simple and complex arm and hand movements on the side contralateral to transplantation in one patient at 5 months postoperatively. Positron emission tomography demonstrated no increased uptake of 6-L-(18F)-fluorodopa in the transplanted striatum at 5 and 6 months. Taken together, these results suggest that the fetal nigral implants may have provided a modest improvement in motor function, consistent with the presence of small surviving grafts. Although our results support further scientific experimentation with transplantation in Parkinson's disease, widespread clinical trials with this procedure are probably not warranted at this time.  相似文献   
3.
A total of 316 patients were included in a play-the-winner (PTW) designed study comparing the safety of enoxaprain started preoperatively versus postoperatively as prophylaxis against venous thromboembolism for digestive surgery. In a PTW-designed study the treatment of any next patient depends on the outcome of the previous patient. If successful, the next patient receives the same treatment, if not, the comparative regimen is given. Excessive bleeding according to specified criteria, severe adverse reactions, clinically detected deep venous thrombosis (DVT), or pulmonary embolism (PE) were criteria for classification as “loser.” The PTW design allocates most patients to the superior treatment. The main variable in PTW studies is the number of consecutive patients receiving the same treatment. In this study 163 patients were allocated to postoperatively started and 153 to preoperatively started prophylaxis with enoxaparin. The frequency of “winners” was found to be 82.8% and 78.4% in the post- and preoperatively treated groups, respectively. No significant differences were found between the groups with regard to frequency of “winners” or the number of consecutive patients before change of treatment. The percentile of survival distribution did not detect superiority of any group. Prophylaxis against postoperative venous thromboembolism for digestive surgery using enoxaparin can safely be started preoperatively.  相似文献   
4.
Serial serum samples from the 21 HIV-infected Norwegian hemophiliacs have been assayed for the presence of HIV antigen and antibodies to HIV specific for the core protein p24 and the envelope protein gp41. HIV antigen was detected in 4 patients, of whom 3 have developed AIDS to date. HIV antigen appeared in serum 10 to 24 months before the diagnosis in these patients. Antibodies to gp41 was a constant finding. Antibodies to p24 disappeared from the serum in 1 patient who developed AIDS and from 3 persons free of symptoms related to the HIV infection. The detection of HIV antigen in HIV antibody-positive hemophiliacs appears to be of considerable prognostic significance.  相似文献   
5.
High frequency electrical stimulation by means of electrodes implanted into the brain has become an accepted technique for treatment of Parkinson's disease. The electrical field distribution normally inserted into the sub thalamic nucleus minimise abnormal brain activity. Square wave pulses of 1–3.6 V with duration of 60–90 μs at a frequency range of 130–185 pps are generally used. Every electrode unit consists of four cylindrical electrodes positioned in a row and can be switched on independently. This paper determines the contact impedance of the electrodes for different frequencies and proposes improvement to reduce the contact impedance between the electrodes and the brain. Measurements were performed by placing the electrodes in a tank filled with saline. Different frequencies were applied on two electrodes via a resistor. The current was measured through the resistor and the voltage was registered between one of the electrodes and a third non current carrying electrode. The obtained values were used to calculate the contact impedance. The result shows large contact impedance for the used frequency compared to the impedance of the treated tissue, which means that variation in contact impedance can result in variation in the electrical field applied to the tissue.  相似文献   
6.
Summary The reliability of noninvasive, automatic blood pressure monitoring is not yet clearly established. A 24-h ambulatory blood pressure profile was obtained in 9 healthy, normotensive subjects with an automatic, noninvasive device. The blood pressure profile showed the typical circadian pattern with lower systolic and diastolic values during sleep, although pulse pressure was fairly constant (about 40 mm Hg). The systolic blood pressure rose steeply in the early morning hours — before waking up. The results were compared with simultaneous hourly readings using the auscultatory method. There were no statistically significant differences between the automatic and auscultatory readings, 13 of the 18 mean values at. different time points being within 2 mm Hg of each other. All the auscultatory means fell within the 95% confidence limits of those measured hourly by the automatic method. Although the automatic method seemed to be reliable compared with the auscultatory method, its sensitivity to motion artifacts is a disadvantage in a truly ambulatory setting.  相似文献   
7.
In many patients with myelodysplastic syndromes or acute myeloid leukemia, complex chromosome aberrations can be seen, among which aberrations of chromosome 5 constitute a substantial part. With conventional cytogenetic technique, these aberrations are often identified as deletions or monosomy 5. We analyzed nine patients who, under conventional cytogenetic analysis, showed deletion or monosomy 5. We used fluorescence in situ hybridization with whole-chromosome painting probes to identify the counterpart chromosome and locus-specific identifiers for 5q31 and 5q33 approximately q34. A deletion of 5q was found concomitant with unbalanced translocations. Our results and cases from the literature showed that material from chromosome 5 could be translocated to almost all chromosomes. All patients but one had short survival; this one patient had a preserved 5q31 and 5q33 approximately q34 but a deletion of the q-arm more centromeric than these bands. In eight of the nine patients, further 14 translocations were revealed, not involving chromosome 5.  相似文献   
8.
The aim of this study was to investigate the relationship between mucosal gizzard lesions and caecal Clostridium perfringens counts. Gross pathological changes in the gizzard and small intestine, and caecal C. perfringens counts from 1217 meat-type chickens were recorded during the course of six experiments and were statistically analysed. C. perfringens counts increased significantly (P < 0.001) with the severity of mucosal gizzard lesions. Mucosal gizzard lesions were more prevalent than necrotic enteritis. Correcting for the pen and necrotic enteritis within experiment, mucosal gizzard lesions explained 31.8% of the variation in C. perfringens counts. Mucosal gizzard lesions and age together explained 59.1% of the variation in C. perfringens counts. The mean ages of birds with moderate and severe mucosal gizzard lesions were 1.7 and 0.8 days lower than the mean age of birds with necrotic enteritis, respectively. The association between mucosal gizzard lesions and high C. perfringens counts might be of importance when attempting to improve production efficiency, health and the welfare of the chickens.  相似文献   
9.
Periodontal status was studied at the mesiobuccal, midbuccal and distobuccal aspects of contralateral pairs of canines in 22 postorthodontic patients aged 30 to 51 years with a mean time of 26.4 years (SD, 5.6) out of active treatment. The pretreatment models showed one canine erupting severely to the labial ("ectopic") with a contralateral canine in good arch alignment (control). None of the patients experienced relapse of the "ectopic" canine in a labial direction, and none had missing teeth, malalignment, overhanging restorations or open tooth contacts adjacent to the canines evaluated. Periodontal parameters were examined using a Michigan #0 probe with Williams markings. A nonstandardized light force was used and the measurements were rounded to the nearest millimeter. The results demonstrated statistically significant differences between the canines in probing attachment and bone levels (mean, 0.75; SD, 0.92; P less than 0.01) and width of attached gingiva (mean, 0.50; SD, 1.07; p less than 0.05) at the midbuccal aspects. The reason for these differences could only be speculated upon.  相似文献   
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