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21.
OBJECTIVE: The authors described the influence of specific medical conditions on clinical remission and response of major depression (MDD) in a clinical trial evaluating a care-management intervention among older primary-care patients. METHODS: Adults age 60 years and older were randomly selected and screened for depression. Participants were randomly assigned to Usual Care or to an Intervention with a depression care-manager offering algorithm-based care for MDD. In all, 324 adults meeting criteria for MDD were included in these analyses. Remission and response was defined by a score on the Hamilton Rating Scale for Depression <10 and by a decrease from baseline of > or =50%, respectively. Medical comorbidity was ascertained through self-report. Cognitive impairment was defined by a score <24 on the Mini-Mental State Exam (MMSE). RESULTS: In Usual Care, rates of remission were faster in persons who reported atrial fibrillation (AF) than in persons who did not report AF and slower in persons who reported chronic pulmonary disease than in persons who did not report chronic pulmonary disease; rates of response were less stable in persons with MMSE <24 than in those with MMSE > or =24. In the Intervention condition, none of the specific chronic medical conditions were significantly associated with outcomes for MDD. CONCLUSIONS: Because disease-specific findings were observed in persons who received Usual Care but not in persons who received more intensive treatment in the Intervention condition, our results suggest that the association of medical comorbidity and treatment outcomes for MDD may be determined by the intensity of treatment for depression.  相似文献   
22.
Tuberculosis involving the soft tissue from adjacent bone or joint is well recognized. However, primary tuberculous pyomyositis, tuberculous bursitis, and tuberculous tenosynovitis are rare entities constituting 1% of skeletal tuberculosis. Tuberculous tenosynovitis involves most commonly the tendon sheaths of the hand and wrist, and tuberculous bursitis occurs most commonly around the hip. The greater trochanteric bursa and the greater trochanter are the most frequent sites of tuberculous bursitis. Cases of primary tuberculous pyomyositis and tenosynovitis of the tendons of the ankle and foot are seldom reported in the radiology literature. All imaging modalities-plain radiography, bone scan, computed tomography, and magnetic resonance imaging (MRI)--provide information that is helpful in determining therapy. MRI in particular, with its multiplanar capabilities and superb contrast of soft tissue, can demonstrate the extent of the soft tissue mass and access the adjacent bones and joints. However, MRI has no diagnostic specificity in regard to tuberculosis, and in nonendemic areas, biopsy is strongly recommended. All patients in this review were permanent residents of North America or Western Europe and were immunocompetent. Examples of atypical presentations of the above entities are demonstrated.  相似文献   
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Monoclonal antibodies against human and bovine 2′:3′-cyclic nucleotide 3′-phosphodiesterase (CNPase) were generated by fusing FOX-NY myeloma cells with spleen cells from RBF/Dn mice previously immunized with the purified brain antigens. The enzyme isolated from bovine brain was quite basic, with an isoelectric point of 9.71 and both the bovine and human enzymes consisted of a closely spaced doublet at approximately 44 and 46 kDa on SDS-PAGE. Six monoclonals were identified as strongly recognizing the enzyme on both ELISA plates and on immunoblots of whole brain protein. Four monoclonals very weakly cross-reacted with guinea pig myelin basic protein. In contrast with two previous reports, some of our monoclonal antibodies did immunostain 2 or 3 protein bands in peripheral nerve, two bands closely corresponding to those immunostained in central nervous system (CNS) myelin, the Wolfgram protein fraction and in acetone powders of whole brain. Each of the 6 monoclonals reacting strongly on immunoblots recognized the enzyme in from 2 to 5 of the species examined (human, bovine, rat, mouse and rabbit). In addition, all 6 monoclonals that immunostained the enzyme in whole brain, myelin and Wolfgram protein immunoblots recognized both CNP1 (44 kDa) and CNP2 (46 kDa). The two closely spaced protein bands observed on SDS-PAGE and previously stained on immunoblots of CNS CNPase using polyvalent rabbit anti-bovine CNPase antisera, and now different monoclonal antibodies, appear to be immunologically related and to contain highly conserved sequences.  相似文献   
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OBJECTIVE: The more atherogenic lipid profile seen in peritoneal dialysis (PD) patients cannot fully explain the increased incidence of atherosclerosis in this population. Oxidative modification of low-density lipoproteins (LDL) is considered to play a central role in the atherogenic process, whereas high-density lipoprotein (HDL) protects LDL from oxidation. On the other hand, it has been suggested that the LDL and HDL of PD patients are more resistant to oxidation than those of control subjects, while PD-HDL equally protects LDL from oxidation compared to control-HDL. Two HDL-associated enzymes have been shown to protect both LDL and HDL from oxidation: paraoxonase (PON1) and HDL-associated platelet-activating factor acetylhydrolase (HDL-PAF-AH). Furthermore, low PON1 activity and high total plasma PAF-AH concentration, which represents mainly the LDL-associated enzyme, have been shown to be independent risk factors for coronary artery events in the general population. However, there are limited data regarding possible alterations of these enzymes in PD patients. The aim of our study was to examine the possible alterations of PON1 and PAF-AH activities in patients undergoing PD. DESIGN: A cross-sectional study. SETTING: A university medical center. PARTICIPANTS: 56 PD patients of Caucasian origin and 86 matched controls were studied. MEASUREMENTS: In all subjects, serum PON1 activity toward paraoxon (paraoxonase) and phenylacetate (arylesterase), as well as total serum and HDL-PAF-AH activities were measured; PON1 genetic polymorphisms known to influence PON1 activity (Q192R and M55L) were determined. RESULTS: The PD patients exhibited significantly increased serum PON1 (paraoxonase) and PON1 (arylesterase) activities compared to controls, regardless of the PON1 polymorphisms or the levels of HDL cholesterol. Additionally, PD patients had significantly elevated activities of total serum PAF-AH and HDL-PAF-AH, independently of the levels of LDL or HDL cholesterol. The ratio of HDL-PAF-AH/ total PAF-AH, which has recently been suggested to be a potential marker of atherogenicity, was decreased in these patients compared to controls. Moreover, no difference in the prevalence of PON1 polymorphisms between PD patients and controls was found. CONCLUSION: The elevated activities of PON1 and HDL-PAF-AH could explain the increased resistance of PD-HDL to oxidation; the higher activity of total PAF-AH and the decreased HDL-PAF-AH/ total PAF-AH ratio could contribute to the increased incidence of atherosclerosis in these patients.  相似文献   
27.
Implicit learning was examined in 15 Huntington's disease (HD) patients and 15 control subjects (NC) using a semantic decision-making task. HD patients demonstrated only slightly reduced priming; like NC subjects, their decision times decreased over repeated presentations, though to a somewhat lesser degree. On explicit recognition testing, the HD group made significantly more false positive errors than did the control group, suggesting an impairment of effortful retrieval. The groups displayed equivalent retention of implicitly learned material after 6 months. The striatal neuronal loss of early Huntington's disease does not markedly affect priming or retention of primed stimuli, but may alter explicit memory judgements.  相似文献   
28.
Extracellular single-unit recordings were made in somatosensory cortical barrels of fentanyl-sedated rats. Whiskers were deflected singly or in paired combinations. lontophoretically-applied (−)-baclofen disproportionately reduced weak responses, and phaclofen disproportionately increased them, resulting in more tightly focused or more broadly focused receptive fields, respectively. Both drugs had only minor effects on surround inhibition. In light of previous findings, we conclude that GABAA and GABAB mechanisms both act to enhance spatial contrast, but that the former plays a much greater role in enhancing temporal resolution.  相似文献   
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The neuropeptide neurotensin (NT) has been shown to modulate mesolimbic dopaminergic activity. Neurotensin injected into the VTA produces motor stimulation and release of dopamine in the nucleus accumbens. In contrast, when neurotensin is administered into the nucleus accumbens, it produces neuroleptic-like effects such as attenuation of the locomotor activity elicited by psychostimulants. In the present study, the hypothesis that neurotensin injected into the nucleus accumbens might modulate the psychostimulant and reinforcing actions of cocaine was tested. In experiment one, rats were trained to self-administer cocaine intravenously on an FR5 schedule of reinforcement. Following the establishment of baseline responding, rats were implanted with bilateral cannulae in the nucleus accumbens. One week later, rats were injected into the nucleus accumbens with various doses of neurotensin (4.2, 8.4 and 16.7 μg, total doses bilaterally) immediately prior to the self-administration session. No significant effects were found with any of the doses of neurotensin tested on the self-administration of cocaine. However, in experiment 2, neurotensin at doses of 4.2 and 16.7 μg injected into the nucleus accumbens significantly reduced the locomotor activation induced by an acute injection of cocaine (15 mg/kg i.p.) and a dose of 16.7 μg attenuated the locomotor activation induced by amphetamine (0.75 mg/kg i.p.). Thus, neurotensin in the nucleus accumbens appears to specifically modulate the acute locomotor activating properties of cocaine but not cocaine self-administration. Different mechanisms by which NT interacts with dopamine in the nucleus accumbens may provide a means of selectively altering psychostimulant motor actions without affecting psychostimulant reinforcement.  相似文献   
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