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81.
82.
A 67-year-old man with risperidone-responsive segmental dystonia underwent bilateral deep brain stimulation (DBS) of the globus pallidus internus. Prospectively, the authors assessed the Burke-Fahn-Marsden Dystonia Rating Scale in medication (M) and stimulation (S) "on"/"off" states. With DBS at 9 months, the score improved by 86% to 8.5 in M-"on"/S-"on" and 12.5 in M-"off"/S-"on." Studies of the effects of DBS and concomitant medication may be warranted in selected patients treated by DBS for dystonia.  相似文献   
83.
Patients who have not received previous antiretroviral treatment (ART) have a high failure rate on the combination treatment of abacavir, lamivudine, and tenovir. We assessed the virological failure rate in eight patients with HIV-1 who switched to this combination after having complete virological suppression from their previous long-term ART (median 8.0 months, range 7.5-18.0). Five of the eight patients showed virological failure. Four of these five patients had either the K65R mutation, the M184V/I mutation, or both. This combination of drugs cannot therefore be recommended as alternative treatment in patients with HIV-1 who are fully virologically suppressed.  相似文献   
84.
The centre median-parafascicular (CM-Pf) complex of the thalamus is considered to be a possible target for deep brain stimulation (DBS) in patients with movement disorders. In a prospective study on the effect of CM-Pf DBS versus somatosensory thalamic DBS on chronic neuropathic pain, three of 12 patients had additional movement disorders. Bifocal quadripolar electrodes were implanted by computed tomography guided stereotactic surgery under local anaesthesia contralaterally to the side of the pain for test stimulation. Two of the three patients with movement disorders had permanent implantation of CM-Pf electrodes. During test stimulation of the left CM-Pf complex for several days, a 67 year old woman received no benefit with respect to the neuropathic pain, but the choreoathetotic movements of her right foot ceased. As the pain syndrome was not improved, she decided not to have permanent implantation. A 74 year old man with postzoster neuralgia and allodynia enjoyed excellent relief from his pain with chronic CM-Pf DBS. In addition, improvement in the tremor at rest was noted. A 72 year old man had sustained reduction in his stump dyskinesias. Further evaluation of the possible role of the "forgotten" central and medial thalamic nuclei in the treatment of movement disorders may be warranted.  相似文献   
85.
Narayanan R  Smith CL  Weigel NL 《BONE》2002,31(3):381-388
Skeletal unloading in an animal hindlimb suspension model and microgravity experienced by astronauts or as a result of prolonged bed rest causes site-specific losses in bone mineral density of 1%-2% per month. This is accompanied by reductions in circulating levels of 1,25-(OH)(2)D(3), the active metabolite of vitamin D. 1,25-(OH)(2)D(3), the ligand for the vitamin D receptor (VDR), is important for calcium absorption and plays a role in differentiation of osteoblasts and osteoclasts. To examine the responses of cells to activators of the VDR in a simulated microgravity environment, we used slow-turning lateral vessels (STLVs) in a rotating cell culture system. We found that, similar to cells grown in microgravity, MG-63 cells grown in the STLVs produce less osteocalcin, alkaline phosphatase, and collagen Ialpha1 mRNA and are less responsive to 1,25-(OH)(2)D(3). In addition, expression of VDR was reduced. Moreover, growth in the STLV caused activation of the stress-activated protein kinase pathway (SAPK), a kinase that inhibits VDR activity. In contrast, the 1,25-(OH)(2)D(3) analog, EB1089, was able to compensate for some of the STLV-associated responses by reducing SAPK activity, elevating VDR levels, and increasing expression of osteocalcin and alkaline phosphatase. These studies suggest that, not only does simulated microgravity reduce differentiation of MG-63 cells, but the activity of the VDR, an important regulator of bone metabolism, is reduced. Use of potent, less calcemic analogs of 1,25-(OH)(2)D(3) may aid in overcoming this defect.  相似文献   
86.
This paper reports on a study that examined both the concurrent and logitudinal connections between multiple components of the home environment and indicators of preschool-aged children's literacy and language development. Data were collected from 85 parents and their children at two different times. Results of structural path models indicated that (a) parental literacy habits were positively associated with parental reading beliefs, (b) parental reading beliefs were positively associated with parent-child literacy and language activities in the home, and (c) parent-child literacy and language activities were positively associated with children's print knowledge and reading interest. Parental demographic characteristics were associated with children's expressive and receptive language skills. The results highlight how different components of the home literacy environment are associated with different components of preschool-aged children's literacy and language abilities, findings that become more important as educators and policy-makers look for ways to enhance children's literacy and language development.  相似文献   
87.

Background  

Adolescence is an important stage of life for establishing healthy behaviors, attitudes, and lifestyles that contribute to current and future health. Health risk behavior is one indicator of health of young people that may serve both as a measure of health over time as well as a target for health policies and programs. This study examined the prevalence and distribution of youth health risk behaviors from five risk behavior domains–aggression, victimization, depression and suicidal ideation, substance use, and sexual behaviors–among public secondary school students in central El Salvador.  相似文献   
88.
Recombinant human thyrotropin (rhTSH) has been evaluated in 38 patients with differentiated thyroid cancer. The patients had all been treated previously by operation and 31 had received radioiodine 131I. The patients continued to take thyroid hormone and changed to a low iodine diet for 14 days before and throughout the week of testing. The rhTSH was injected intramuscularly on two consecutive days, 74 MBq 131I was administered on the next day and scintigraphy completed 48 h after that. TSH was measured before administration of 131I, and thyroglobulin after the scan. All patients preferred this method to withdrawal of thyroid hormone, but 45% had mild symptoms including headache and nausea. The average TSH was 127 mU x l(-1), and was inversely related to the weight of the patients. Thirty-four had negative scans with a mean uptake of 0.06%. Thyroglobulin values above 10 ng x ml(-1) were found in seven patients, of whom four had similar findings when scanned after withdrawal of thyroid hormone. Of four with positive scans, two had undetectable thyroglobulin. The rate of clearance of 131I was compared in patients studied at 72 h who were hypothyroid and at 48 h in euthyroid patients given rhTSH and was found to be longer in the latter. We conclude that rhTSH can be used to stimulate thyroid tissue to trap 131I and secrete thyroglobulin. Both scan and thyroglobulin should be obtained. The method is well tolerated.  相似文献   
89.
Minimally invasive surgical staging for esophageal cancer   总被引:9,自引:0,他引:9  
Background: The incidence of esophageal adenocarcinoma is increasing in the United States, and the 5-year survival rate is dismal. Preliminary data suggest that conventional imaging is inaccurate in staging esophageal cancer and could limit accurate assessment of new treatments. The objective of this study was to compare minimally invasive surgical staging (MIS) with conventional imaging for staging esophageal cancer. Methods: Patients with potentially resectable esophageal cancer were eligible. Staging by conventional methods used computed tomography (CT) scan of the chest and abdomen, and endoscopic ultrasound (EUS), whereas MIS used laparoscopy and videothoracoscopy. Conventional staging results were compared to those from MIS. Results: In 53 patients, the following stages were assigned by CT scan and EUS: carcinoma in situ (CIS; n= 1), I (n= 1), II (n= 23), III (n= 20), IV (n= 8). In 17 patients (32.1%), MIS demonstrated inaccuracies in the conventional imaging, reassigning a lower stage in 10 patients and a more advanced stage in 7 patients. Conclusions: In 32.1% of patients with esophageal cancer, MIS changed the stage originally assigned by CT scan and EUS. Therefore, MIS should be applied to evaluate the accuracy of new noninvasive imaging methods and to assess new therapies for esophageal cancer. Received: 5 April 1999/Accepted: 15 March 2000/Online publication: 12 July 2000  相似文献   
90.
Children suffering malignant diseases can experience phases of bone marrow depression during intensive chemotherapy. The influence of antibiotic sequence therapy on the course of diseases was examined in 41 pediatric patients with malignant diseases. Inclusion criteria were neutropenia (ANC < 500/microL), rectal body temperature over 38.5 degrees C, and increased C-reactive protein (CRP, cutoff > 5.0 mg/L). The first stage of therapy comprised the following antibiotics: piperacillin, teicoplanin, and gentamicin. In stage 2 imipenem, teicoplanin, and tobramycin were administered. Fluconazole was the antifungal drug of choice in stages 1 and 2. In the first level of antibiotic therapy 68% of the patients showed a positive reaction. The C-reactive protein was a sensitive parameter, which significantly decreased with 3 days of therapy. A total of 72% of the bacteriological smears were sterile. All patients survived the septic phase.  相似文献   
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