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41.
The present study investigated the expression of c-erbB-2 in 59 meningiomas, including different histological subtypes and anaplastic variants, by immunocytochemistry and molecular biological techniques. Immunohistochemistry using the monoclonal antibody FWP-51 directed against c-erbB-2-encoded oncoprotein gp185 demonstrated variable degrees of immunoreactivity in all meningiomas. The intensity of immunostaining correlated with the degree of expression as assessed by Western analysis in 28 meningiomas using polyclonal antiserum 21N. There was no correlation between the degree of expression and histological variants. Immunoreactivity of all menigiomas was distinctly less intense, however, than that of the human breast cancer cell line SK-BR-3, and slightly lower than that of brain metastases of breast and ovarian carcinomas that served as positive controls for both methods. By Southern analysis all meningiomas showed a single copy of the c-erbB-2 gene. Non-neoplastic arachnoid cap cells also exhibited c-erbB-2 expression and the degree of immunoreactivity was comparable with the majority of meningiomas. These data argue against an overexpression of c-erbB-2 in meningiomas, but rather indicate a cell-type-specific constitutive expression of the c-erbB-2 gene product in meningiomas and their putative progenitor cells. Since a subgroup of meningiomas is known to express progesterone receptors (PR), gp185 immunoreactivity was compared to the hormone receptor status using monoclonal antibody KD68. Fifty-six percent meningiomas showed PR immunoreactivity, but there was no statistically significant correlation with the degree of gp185 expression.This study was supported by a grant of the Tumorzentrum Heidelberg/Mannheim (M.K., No. 10028060)  相似文献   
42.
Background - A case of primary thyroid T cell lymphoma leading to lethal tracheal perforation during chemotherapy is described.  相似文献   
43.
Rehabilitation for geriatric patients, as well as rehabilitation for patients with a chronic disease, strives to mobilize individuals' residual capacity for optimal function in their usual environment. It is clear from observational studies that chronic dialysis patients often experience marked limitations in physical functioning, and these limitations tend to increase with patients' age. However, both prospective studies and controlled trials conducted with elderly persons demonstrate that muscle strengthening and cardiovascular exercise are related to improved physical functioning, and there is evidence that dialysis patients can also benefit from many of these interventions. Inpatient rehabilitation in a specialized geriatric unit has been shown to be associated with better functional outcomes and decreased need for institutionalization among elderly persons; the process of comprehensive geriatric assessment may also have beneficial outcomes. More controlled studies are needed in order to better specify the effectiveness of various geriatric interventions, for elderly subjects in general and for elderly dialysis patients specifically.  相似文献   
44.
The development of a unifying framework for conceptualizing the commonalities in various forms of substance abuse must encompass the data base focused upon the stimulus functions of drugs. In the first instance, for example, the research on drug self-administration has provided convincing evidence of a remarkable concordance between laboratory animals and human substance abusers in the reinforcing stimulus functions of a range of chemical agents. The recognition of these cross-species and cross-drug generalities has radically changed conceptualizations of substance abuse from a reactive to a more active process and has encouraged the kind of functional analysis of drug-seeking and drug-taking that has proven productive and useful in the study of other behavioral interactions. In this regard as well, recent refinements in the analysis of the discriminative stimulus functions of drugs have provided a more comprehensive basis for characterizing a chemical agent's spectrum of action and evaluating its abuse liability. While the correlation between the discriminative stimulus functions and the reinforcing stimulus functions is remarkably high for some drug classes, there are notable exceptions. Finally, the assessment of abuse liability requires an analysis of the eliciting stimulus functions of drugs as reflected by the physiological and behavioral changes, both acute and chronic, that follow drug administration. The methods used to evaluate both physiological dependence and behavioral toxicity in relationship to sensory and motor effects for a range of abused drugs have depended heavily upon an assessment of the eliciting stimulus functions of such compounds.  相似文献   
45.
The authors systematically evaluated the frequency patterns of cocaine use in 85 cocaine-dependent outpatients and found four patterns of use: continuous (27%), intermittent patterned (35%), intermittent nonpatterned (25%), and occasional (13%). Few subjects reported consistent cycling between binges and crashes. There were no significant differences in patterns of use associated with gender, race, educational level, route of administration, or recency of heroin use. Continuous users and occasional users were older than intermittent users. Because different contingencies may control patterned vs. nonpatterned cocaine use, pattern of use may have implications for treatment, even in individuals reporting similar amounts of cocaine use.  相似文献   
46.
The in vitro permeabilities of Caco-2 monolayers and permeabilities in tissue sections from colon of monkey, rabbit, and dog were compared using a series of compounds. The selected compounds differed in their physicochemical properties, such as octanol/water partition coefficient, water solubility, and molecular weight. Their structure included steroids, carboxylic acids, xanthins, alcohols, and polyethylene glycols. A linear permeability relationship was established between Caco-2 and colon tissue from both rabbit and monkey. The results suggest that Caco-2 is twice as permeable as rabbit and five times as permeable as monkey colon. However, no clear relationship could be established between Caco-2 monolayers and dog colon permeability. A relationship between permeability in Caco-2 monolayers and human absorption was found. The results suggest that within certain limits, permeability of Caco-2 monolayers may be used as a predictive tool to estimate human drug absorption.  相似文献   
47.
This paper concerns the diagnostic classification of nonaffective acute remitting psychosis (NARP), which we also term acute brief psychosis. We argue that NARP can be delineated from both schizophrenia and the affective psychoses and considered as a single diagnosis. As indicated by the term NARP, four criteria would be central to the diagnosis: 1. nonaffective, 2. acute onset (over less than two weeks), 3. recovery within a brief duration (less than six months), and 4. psychosis broadly defined. We review the rationale and the empirical evidence for this proposed classification.  相似文献   
48.
Toxic-shock-syndrome toxin-1 (TSST-1), a 22-kilodalton (kDa) polypeptide, was proteolyzed by papain, generating three distinct fragments, identified as 16, 12, and 10 kDa (based on molecular masses estimated from the predicted amino acid sequence). The NH2-terminal sequence analysis of the fragments indicated that the peptide bonds between Tyr-52 and Ser-53 and between Gly-87 and Val-88 were cleaved. Functional activity, evaluated through enzyme-linked immunosorbent and inhibition assays, was demonstrated only with the 16- and 12-kDa fragments. The presence of homologous and heterologous antigenic determinants on the fragments was demonstrated by immunoblotting. In in vitro stimulation of human peripheral blood mononuclear cells, the 12-kDa fragment was significantly (P = .003) more active than the 16-kDa fragment. The former composed 75% of the latter and occupied the COOH-terminal portion of the holotoxin. The functional domains were located on two-thirds of the TSST-1 molecule, toward the COOH-terminal end, and mitogenicity apparently was separable from serological activity.  相似文献   
49.
Global self-rated health (SRH) is increasingly a key indicator in the assessment of immigrant health. However, evidence of the impact on SRH of generational status, duration of residence in the US, and socioeconomic status (SES) among immigrants and their offspring is limited and inconsistent. We overcome limitations in existing research on this topic by using a uniquely large and diverse data source, the March Annual Social and Economic Supplement of the Current Population Survey (CPS; 2003–2007) (n = 637,209). As a result, we are able to disaggregate results by race/ethnicity, account for country of origin, and consider the role of multiple dimensions of SES. We find that overall first-generation immigrants in the US have lower odds of poor/fair SRH compared to the third-generation. This association is particularly strong for blacks and Hispanics but not significant for Asians. Among first-generation Asians and Hispanics, longer duration of residence is positively associated with poor/fair SRH. Finally, socioeconomic gradients in SRH tend to be less pronounced among the first-generation (versus the third) and, within the first-generation, among recent arrivals (versus those with longer durations). Our results highlight the importance of explicitly accounting for multiple immigration-related variables and their interactions with race/ethnicity and SES. Otherwise, studies may misestimate SRH differences by race/ethnicity and socioeconomic status. The continued growth of the US immigrant population and the second-generation underscore the need to examine patterns in immigrant health systematically.  相似文献   
50.
We have constructed a new capsid-modified adenovirus (Ad) vector that specifically replicates in tumor cells and expresses TNF-related apoptosis-inducing ligand (TRAIL). The Ad capsid contains short-shafted fibers derived from Ad serotype 35, which allow for efficient infection of malignant tumor cells, and largely avoids innate toxicity after intravenous application. Replication-dependent homologous recombination in Ad genomes was used to achieve tumor-specific expression of Ad E1a (to mediate viral replication) and TRAIL (to mediate apoptosis and enhance release of progeny virus from infected cells). We demonstrated that our oncolytic vector (Ad5/35.IR-E1A/TRAIL) induced apoptosis in human tumor cell lines derived from colorectal, lung, prostate, and liver cancer. Both in vitro and in vivo tumor models showed efficient intratumoral spread of this vector. In a model for metastatic colon cancer, tail vein infusion of Ad5/35.IR-E1A/TRAIL resulted in elimination of preestablished liver metastases. Intravenous injection of this vector caused a transient elevation of serum glutamic pyruvic transaminase in tumor-bearing mice, which we attributed to factors released from apoptotic tumor cells. Liver histology analyzed at day 14 after virus injection did not show signs of hepatocellular damage. This new oncolytic vector represents a potentially efficient means for gene therapy of metastatic cancer.  相似文献   
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