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971.
972.
Patellar plical syndrome is a commonly reported, yet controversial entity. Arguments exist as to which component of the patella plica is most commonly involved clinically. The authors describe a plical structure which is seldom identified as a source of pathology. This structure, however, can be a primary source of pain accompanying extensor mechanism dysfunction. The aforementioned structure has been identified via arthroscopic technique, cadaveric dissection, and by palpation during clinical examinations. Conservative and surgical management is discussed.J Orthop Sports Phys Ther 1988;9(9):305-309.  相似文献   
973.
The occurrence and clinical significance of thought disorder, as measured by general abstraction ability and idiosyncratic abstractions, remains a complex and ambiguous area of inquiry. We studied 49 subjects in a longitudinal design in which the effects of general psychopathology and depression on abstraction function were assessed. Results indicate that a) depressive patients have a generalized abstraction dysfunction not limited to specific content areas, b) some depressive patients have a residual abstraction deficit on discharge from the hospital, c) idiosyncratic abstractions are a characteristic but not pathognomonic marker for schizophrenia, and d) across all subjects, abstraction difficulties represent a seemingly state-dependent "final common pathway" that significantly correlates with general psychopathological impairment rather than level of depression.  相似文献   
974.
Synaptosomes isolated from rat cerebra were used as a model to study the effects of halothane on choline uptake and acetylcholine synthesis and release processes. Synaptosomes are membrane-bound particles that are formed by gentle disruption of brain tissue. These particles include the presynapse, cleft, portions of postsynaptic membrane, and all other components contained in brain nerve terminals necessary for neurotransmitter synthesis, storage, and release. Halothane (3% in air, vol/vol) caused a "competitive-like" inhibition of choline uptake in synaptosomes but had no effect on the enzymatic activity of choline acetyl-transferase (ChAT). Three percent halothane depressed synaptosomal acetylcholine (ACh) synthesis by 86% while ACh release from synaptosomes was inhibited 50%. It is suggested that halothane inhibits ACh synthesis by directly interfering with the carrier-mediated transport system of choline. Since halothane also inhibits ACh release, as well as choline uptake, it is probable that the anesthetic is acting upon more than one site in these cholinergic nerve terminals. These data require an interpretive evaluation that cannot fit the "unitary" hypothesis as the mechanism of action of general anesthetics.  相似文献   
975.
Recent theoretical and empirical research has highlighted the importance of understanding the relationship between social structure and health beliefs. The empirical study described here explores the relationships between occupational social class and two dimensions of health beliefs which were concepts of health and perception of vulnerability to disease. Both the dimensions are claimed to be associated with decisions to carry out health behaviour and thus one of the aims was to shed some light on the social class gradient in patterns of preventive health behaviour and risk-taking behaviour. The findings showed a more marked social class differentiation in concepts of health when they were defined in the abstract compared with when they were defined in relation to personal health. The concept of personal vulnerability itself was shown to be problematic and theories about vulnerability were similar for both classes. Explanations for the findings are discussed.  相似文献   
976.
977.
Lens junctional protein: analyzing MP26 with monoclonal antibodies   总被引:1,自引:0,他引:1  
Specific antibodies are versatile tools for analyzing cell surface proteins. This study involves the characterization of monoclonal antibodies which are specific for the junctional protein found in the lens fiber cell. This protein can be expected to include regions on the external membrane surface for junction formation, others on the cytoplasmic surface for regulation of junctional properties and, if cell-cell channels are indeed involved, transmembrane domains forming the hydrophilic connection between adjacent cytoplasms. Antibodies to these various regions would provide for an experimental analysis of the junctional protein, e.g., the identification of "active sites" for junction formation. Three monoclonal antibodies specific for the lens junctional protein in the chicken are described here. The first, termed B2, also recognizes the bovine junctional protein, MP26 (5). We have characterized the submolecular specificity of B2 and have found that it binds approximately ten amino acid residues from the C-terminus of MP26. In isolated lens junction preparations, B2 binds to the cytoplasmic surfaces of the lens junctions (both 12 nm and 16 nm thick forms). Thus, we consider MP26 a component of the lens junction. Monoclonal A4, the second antibody considered in detail here, was produced by immunization with lens membranes after treatment with low pH. We have found that lens junctional membranes are separated, or "split," by treatment at pH 2.5-3.0. It appears that A4 binds to the external surface of the junctional membrane; EM studies to confirm this are in progress. In order to map the A4 binding site within the chicken junctional protein and to explore the arrangement of this protein within the membrane, a number of procedures were used to generate fragments of MP26. These included reactions with N-chlorosuccinimide and proteases after acid treatment. Antibody binding to fragments was evaluated with immunotransfer ("Western") procedures. These studies mapped the A4 binding site to the center of the molecule and suggested that MP26 projected externally from the membrane at two different points. These results are consistent with a recent model, based on sequence data (6), for the arrangement of MP26 within the bovine lens membrane.  相似文献   
978.
The survival of patients with cancer of the stomach in a Melbourne series showed no improvement over a 20-year period. Of 246 patients, 8.1% survived for a period of five years, and 4.8% survived for 10 years after presentation. A further plea is made to establish a "100%" register of cancer.  相似文献   
979.
980.
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