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41.
Studied Minnesota Multiphasic Personality Inventory (MMPI) profiles of 362 patients with acute and chronic low back pain (LBP) for replicable homogeneous subgroups using 3 cluster-analysis procedures. Two normal and 3 clinically elevated profile subgroups were identified. The 2 normal subgroups were characterized by relatively normal musculoskeletal condition and were least disabled but differed from each other in duration of pain, presence of physical abnormalities, and daily functioning. The most pathologic profile subgroup consisted largely of acute-pain patients whose musculoskeletal condition and daily functioning were similar to those of the normal subgroups. Patients in the 3 abnormal MMPI subgroups were exposed to more LBP physical-risk factors in the workplace. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
42.
A simple, rapid, accurate and reproducible capillary electrophoretic method was developed for the assay of glycyrrhizin and glycyrrhetinic acid in traditional Chinese medicinal preparations. The buffer solution used in this method was acetonitrile and 0.02 M sodium dihydrogen-phosphate solution adjusted to pH 7.5 with 0.05 M sodium hydroxide. The linear calibration range was 0.04-2.00 mg/ml (r = 0.9988) for glycyrrhizin and 0.007-0.35 mg/ml (r = 0.9985) for glycyrrhetinic acid and recoveries were 98.1-101.3% for glycyrrhizin and 98.5-101.4% for glycyrrhetinic acid. The relative standard deviations were 1.02% (n = 6) for glycyrrhizin and 0.91% (n = 6) for glycyrrhetinic acid. The content of these two acids in Glycyrrhizae Radix and Glycyrrhizae Radix-containing Chinese medicinal preparations was successfully determined within 10 min.  相似文献   
43.
N-acetyl cysteine is an agent which has been shown to interrupt signal transduction processes linking a wide range of stimuli to the activation of NF-kappa B in mammalian cells. We have investigated its effect on the early development of Xenopus embryos by injecting it into blastulae, using concentrations comparable to those effective on cultured cells. High concentrations at the late blastula or early gastrula stage suppress posterior and enhance anterior development, yielding embryos with enlarged cement glands and otherwise consisting of little except head in extreme cases. Reducing the amount of N-acetyl cysteine injected leads to progressively more posterior structures developing. Injection into one- or two-cell embryos gives similar phenotypes, but of reduced severity and the cement gland is not so enlarged. Explants of animal cap cells taken several hours after injection develop to give large amounts of cement gland material. We have examined the expression of a number of genes in the anteriorised embryos. Posterior markers and Xsna are reduced. Noggin and Goosecoid mRNA are up-regulated through the gastrula and persist at these levels until at least the late neurula stage, whereas in controls Noggin is much lower and Goosecoid is absent at these stages. The most anteriorised phenotype may be a consequence of this changed expression.  相似文献   
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Current diagnostic criteria for Alcohol Related Dementia (ARD) are based almost exclusively on clinical judgment. Moreover, there are no guidelines available to assist the clinician or the researcher in distinguishing Alcohol Related Dementia from other causes of dementia such as Alzheimer's Disease (AD). However, this distinction may have implications for the prognosis and treatment of patients. In this article, provisional diagnostic criteria for establishing a diagnosis of Alcohol Related Dementia are proposed for further study. The criteria are based on the available literature on the relationship between alcohol consumption and dementia and were modeled after existing diagnostic criteria for AD and Vascular Dementia. Validity of these criteria for distinguishing AD from ARD will require further study.  相似文献   
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47.
Tlg1p and Tlg2p, members of the syntaxin family of SNAREs in yeast, have been implicated in both endocytosis and the retention of late Golgi markers. We have investigated the functions of these and the other endocytic syntaxins Pep12p and Vam3p. Remarkably, growth is possible in the absence of all four proteins. In the absence of the others, Pep12p and Tlg1p can each create endosomes accessible to the endocytic tracer dye FM4-64. However, although Pep12p is required for the ligand-induced internalization of the alpha factor receptor and its passage via Pep12p-containing membranes to the vacuole, Tlg1p is not. In contrast, Tlg1p is required for the efficient localization of the catalytic subunit of chitin synthase III (Chs3p) to the bud neck, a process that involves endocytosis and polarized delivery of Chs3p. In wild-type cells, internalized Chs3p cofractionates with Tlg1p and Tlg2p, and in a strain lacking the other endocytic syntaxins, either Tlg1p or Tlg2p is sufficient for correct localization of the enzyme. Pep12p is neither necessary nor sufficient for this process. We conclude that there are two endocytic routes in yeast that can operate independently and that Tlg1p is located at the junction of one of these with the polarized exocytic pathway.  相似文献   
48.
The antifibrotic effect of the mismatched double-stranded RNA, Ampligen (poly(I).poly(C12U)), was evaluated in a bleomycin-mouse model of pulmonary fibrosis. Mice received a single intratracheal dose of bleomycin (0.125 U/mouse) or saline (50 microL) at the beginning of the experiment, followed by 5 or 6 intraperitoneal injections of Ampligen (1.0, 5.0, 10.0, 15.0, or 25.0 mg/kg) or saline at regular intervals for 2 weeks. Ampligen did not produce increased mortality or weight loss by itself. However, it produced varying degrees of mortality in combination with bleomycin. Five injections of 10 mg/kg Ampligen or three injections of 25 mg/kg Ampligen plus three injections of 10 mg/kg Ampligen in combination with bleomycin .produced significant reductions in lung collagen accumulation as indicated by lung hydroxyproline content compared to the bleomycin control group. Animals receiving bleomycin plus Ampligen at all dosages had significantly reduced prolyl hydroxylase activity compared to the bleomycin control group. Lipid peroxidation and bronchoalveolar lavage fluid (BALF)-supernatant protein content for the groups receiving bleomycin plus Ampligen were not reduced compared to the bleomycin control group. In the BALF-supernatant, the activity of acid phosphatase, a lysosomal enzyme produced by neutrophils, monocytes, and macrophages, was significantly decreased in the group receiving bleomycin plus 10 mg/kg Ampligen. Also, selected BALF differential immune cell counts were reduced in some of the groups receiving bleomycin plus Ampligen, but not in a consistent or dose-dependent manner. The results of this study indicate that Ampligen can significantly reduce the bleomycin-induced increased collagen accumulation and may be therapeutically useful in the management of lung fibrosis in humans.  相似文献   
49.
The early phases of T-cell development require both cell-cell interactions and soluble factors provided by stromal cells within the thymic microenvironment. Still, the precise nature of the signals delivered in vivo by cytokines (resulting in survival, proliferation or differentiation) remains unclear. Recent studies using mice deficient in cytokines or in their receptors have helped to identify essential signaling pathways required for the development of intrathymic precursors to mature alpha beta and gamma delta T cells. In addition, cytokine requirements for the development of natural killer cells were revealed in such mutants. The results obtained demonstrate that the development of all classes of lymphocytes (natural killer, gamma delta T cells and alpha beta T cells) is cytokine dependent, but the specific requirements differ for each lineage.  相似文献   
50.
We evaluated 48 archival cases of acute erythroleukemia and divided them into 3 groups: M6a, corresponding to the traditional French-American-British M6 category; M6b, which is pure erythroleukemia; and M6c, in which myeloblasts and pronormoblasts each account for more than 30% of cells by the French-American-British exclusion criteria. No significant differences were noted among the subtypes for ratio of males to females; age; or exposure to toxins, alcohol, or both. However, compared with the patients in the M6a group, patients in the M6b and M6c groups demonstrated a statistically significant increase in cytogenetic aberrations, proliferation markers (proliferating cell nuclear antigen and Ki67), and ringed (type III) sideroblasts. Marked survival differences were noted between the M6a (30.1 +/- 29.5 months) and M6b (3.15 +/- 4.2 months) groups, with patients in the M6c group demonstrating an intermediate prognosis (10.5 +/- 12.7 months). Chemotherapeutic regimens induced remission in all treated patients in the M6a and M6c groups but did not appear to affect the M6b group. However, the patients in the M6c group remained in remission for a significantly shorter period of time than did patients in the M6a group. Overall, survival appeared to depend on the ratio of pronormoblasts to myeloblasts at diagnosis and demonstrated a rapid decline with increasing pronormoblast and decreasing myeloblast counts. We must, therefore, devise chemotherapeutic regimens that target both blastic components of this disease.  相似文献   
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