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991.
Background and purpose An increasing number of lumbar fusions are performed using allograft to avoid donor-site pain. In elderly patients, fusion potential is reduced and the patient may need supplementary stability to achieve a solid fusion if allograft is used. We investigated the effect of instrumentation in lumbar spinal fusion performed with fresh frozen allograft in elderly patients.Methods 94 patients, mean age 70 (60–88) years, who underwent posterolateral spinal fusion either non-instrumented (51 patients) or instrumented (43 patients) were followed for 2–7 years. Functional outcome was assessed with the Dallas pain questionnaire (DPQ), the low back pain rating scale pain index (LBPRS), and SF-36. Fusion was assessed using plain radiographs.Results Instrumented patients had statistically significantly better outcome scores in 6 of 7 parameters. Fusion rate was higher in the instrumented group (81% vs. 68%, p = 0.1). Solid fusion was associated with a better functional outcome at follow-up (significant in 2 of 7 parameters). 15 patients (6 in the non-instrumented group and 9 in the instrumented group) had repeated lumbar surgery after their initial fusion procedure. Functional outcome was poorer in the group with additional spine surgeries (significant in 4 of 7 parameters).Interpretation Superior outcomes after lumbar spinal fusion in elderly patients can be achieved by use of instrumentation in selected patients. Outcome was better in patients in which a solid fusion was obtained. Instrumentation was associated with a larger number of additional surgeries, which resulted in a lesser degree of improvement. Instrumentation should not be discarded just because of the age of the patient.  相似文献   
992.
BACKGROUND: Prostate-specific membrane antigen (PSMA) is a transmembrane glycoprotein primarily expressed on benign and malignant prostatic epithelial cells. J591 is an IgG1 monoclonal antibody that targets the external domain of the PSMA. The relationship among dose, safety, pharmacokinetics, and antibody-dependent cellular cytotoxicity (ADCC) activation for unlabeled J591 has not been explored. PATIENTS AND METHODS: Patients with progressive metastatic prostate cancer despite androgen deprivation were eligible. Each patient received 10, 25, 50, and 100 mg of J591. Two milligrams of antibody, conjugated with the chelate 1,4,7,10-tetraazacyclododecane-N, N',N',N'-tetraacetic acid, were labeled with 5 mCi indium-111 (111In) as a tracer. One group of patients received unlabeled J591 before the labeled antibody; the other received both together. Toxicities, pharmacokinetic properties, biodistribution, ADCC induction, immunogenicity, and clinical antitumor effects were assessed. RESULTS: Fourteen patients were treated (seven in each group). Treatment was well tolerated. Biodistribution of 111In-labeled J591 was comparable in both groups. The mean T1/2 was .96, 1.9, 2.75, and 3.47 days for the 10, 25, 50, and 100 mg doses, respectively. Selective targeting of 111In-labeled J591 to tumor was seen. Hepatic saturation occurred by the 25-mg dose. ADCC activity was proportional to dose. One patient showed a >50% prostate-specific antigen decline. CONCLUSIONS: J591 is well tolerated in repetitive dose-escalating administrations. The rate of serum clearance decreases with increasing antibody mass. ADCC activation is proportional to antibody mass. The optimal dose is 25 mg for radioimmunotherapy and 100 mg for immunotherapy. Phase II studies using J591 as a radioconjugate are under way.  相似文献   
993.
Patients with 22q11.2 deletion syndrome (22q11.2DS) represent a population at high risk for developing schizophrenia, as well as learning disabilities. Deficits in visuo-spatial memory are thought to underlie some of the cognitive disabilities. Neuronal substrates of visuo-spatial memory include the inferior fronto-occipital fasciculus (IFOF) and the inferior longitudinal fasciculus (ILF), two tracts that comprise the ventral visual stream. Diffusion Tensor Magnetic Resonance Imaging (DT-MRI) is an established method to evaluate white matter (WM) connections in vivo. DT-MRI scans of nine 22q11.2DS young adults and nine matched healthy subjects were acquired. Tractography of the IFOF and the ILF was performed. DT-MRI indices, including Fractional anisotropy (FA, measure of WM changes), axial diffusivity (AD, measure of axonal changes) and radial diffusivity (RD, measure of myelin changes) of each of the tracts and each group were measured and compared. The 22q11.2DS group showed statistically significant reductions of FA in IFOF in the left hemisphere. Additionally, reductions of AD were found in the IFOF and the ILF in both hemispheres. These findings might be the consequence of axonal changes, which is possibly due to fewer, thinner, or less organized fibers. No changes in RD were detected in any of the tracts delineated, which is in contrast to findings in schizophrenia patients where increases in RD are believed to be indicative of demyelination. We conclude that reduced axonal changes may be key to understanding the underlying pathology of WM leading to the visuo-spatial phenotype in 22q11.2DS.  相似文献   
994.
The history of eating disorders in Norway is described in four phases: (1) early case histories of eating disorder symptoms in the late 19th century Norwegian medical literature, (2) the pioneers of the post‐World War 2 decades, (3) the 1980s when eating disorders became visible to the public and a focus of interest among professionals, and (4) the consolidation of professional networks and the emergence of a national policy for treatment. In contrast to many other countries, the official Norwegian policy is to improve clinical competence and knowledge about eating disorders at all levels of health care rather than establishing special clinics. Beside arguing for such a policy, we suggest that discussing the balance between general and specialist services is an important future issue. Copyright © 2001 John Wiley & Sons, Ltd and Eating Disorders Association.  相似文献   
995.
Diagnosis of Hirschsprung disease (HSCR) relies on histologic and/or histochemical staining of sections from suction rectal biopsies. Acetylcholinesterase histochemistry (AChE) facilitates diagnosis but is not universally employed, in part because it requires special tissue handling. Calretinin immunohistochemistry (IHC) may be a useful alternative, because loss of calretinin immunoreactive nerves reportedly correlates spatially with aganglionosis. We investigated the patterns of calretinin IHC in suction rectal biopsies from HSCR and non-HSCR patients and compared the diagnostic value of calretinin IHC with a widely used rapid AChE method. In suction rectal biopsies that contain ganglion cells, small nerves in the lamina propria, muscularis mucosae, and superficial submucosa contain granular aggregates of calretinin immunoreactivity. Immunolabeling of these nerves is completely absent in the aganglionic biopsies of HSCR patients. Multiple observers independently reviewed calretinin IHC and AChE sections of suction rectal biopsies from 14 HSCR patients and 17 non-HSCR controls. Five observers, blinded to the correct diagnosis, scored each patient's calretinin IHC and AChE slides as HSCR, not HSCR, or equivocal. The frequencies of major and minor discrepant diagnoses were compared. Calretinin IHC yielded no misdiagnoses or major discrepancies between observers. In contrast, 2 misdiagnoses and significantly more interobserver disagreement resulted from the AChE-stained sections. Calretinin IHC appears to be a reasonable, and potentially superior, alternative to AChE as an adjunctive diagnostic method for evaluating suction rectal biopsies for HSCR.  相似文献   
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BACKGROUND: Serogroup C meningococcal conjugate polysaccharide vaccines have been reported to induce significant serum IgG antibodies and immunologic memory in infants. Because meningococcus is a mucosal pathogen colonizing the nasopharynx, local mucosal immune responses may play an important role in host defense against infection and carriage. We have investigated the mucosal IgA and IgG antibody responses to two meningococcal C conjugate vaccines in the saliva of healthy infants. METHODS: Specific salivary IgA and IgG antibodies to two meningococcal C polysaccharide conjugate vaccines (Menjugate from Chiron Corp., n = 46; and Meningitec from Wyeth Lederle, n = 54) were investigated by immunoassay in infants after parenteral vaccinations at the ages of 2, 3 and 4 months. Unstimulated saliva samples were collected immediately before the first immunization and 1 month after the third immunizations. Forty healthy infants receiving the same routine vaccines but no meningococcal C vaccine were recruited as controls. RESULTS: There were significant increases in meningococcal C polysaccharide-specific IgG antibody concentrations postvaccination compared with prevaccination concentrations in both vaccinated groups (both P < 0.001), but no change in the control group. There were no significant increases in specific IgA postvaccination geometric mean concentrations in either the vaccine or the control groups. The number of IgA positives postvaccination increased slightly in the Wyeth vaccine group vs. controls (P < 0.05). CONCLUSIONS: Significant salivary IgG antibodies to meningococcal C polysaccharide were observed after parenteral immunization with two meningococcal C conjugate vaccines, whereas there was no significant increase in specific IgA antibody levels for these two vaccines.  相似文献   
1000.
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