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951.
The focal adhesion kinase (FAK) has been implicated in signal transduction pathways initiated by cell adhesion receptor integrins and by neuropeptide growth factors. To gain insight into FAK function, we examined the potential interaction of FAK with intracellular signaling molecules containing the Src homology 2 domains. We report here the stable association of FAK with phosphatidylinositol 3-kinase (PI3-kinase; EC 2.7.1.137) in NIH 3T3 mouse fibroblasts. This interaction was stimulated by cell adhesion concomitant with FAK activation. We also found that recombinant FAK bound to the p85 subunit of PI 3-kinase directly in vitro and that autophosphorylation of recombinant FAK in vitro increased its binding to PI 3-kinase. We detected increased tyrosine phosphorylation of the p85 subunit of PI 3-kinase during cell adhesion and observed direct phosphorylation of p85 by FAK in vitro. Together, these results suggest that PI 3-kinase may be a FAK substrate in vivo and serve as an effector of FAK.  相似文献   
952.
The sampling of 50 microliters of the yolk (average 1.7% of the total volume) from northern bobwhite quail (Colinus virginianus) eggs on day 0, 6, 12, and 18 of incubation resulted in significantly (P < 0.05) increased embryo mortality in the day 12 and day 18 egg groups. Performance parameters and reproductive indices of the non-sampled eggs and the eggs sampled on day 0, and 6 of incubation did not differ from other reports on C. virginianus. No differences was found in postnatal responsiveness among hatchlings originating from controls and from all the groups of sampled eggs. As demonstrated in this representative galliform species, the technique can be applied for the screening of unembryonated eggs or early-embryogenesis-eggs of wild birds. If female birds are not accessible but their eggs are, information on the reproductive flock can be accessed without stressing adult birds.  相似文献   
953.
954.
BACKGROUND: Musculoskeletal complaints are common and often unexplained and often lead to rheumatology referrals. The prevalence of psychiatric disease in patients with musculoskeletal complaints is unknown. OBJECTIVES: To determine the prevalence of common psychiatric disorders among patients referred to a rheumatology clinic and the likelihood of establishing a rheumatic diagnosis if a psychiatric disorder is present. DESIGN: Prospective diagnostic survey. SETTING: Two hospital-based rheumatology clinics and a general medicine clinic. PARTICIPANTS: A consecutive sample of newly referred patients (n = 185) and their rheumatologists (n = 9). INTERVENTION: Before their visit, all patients filled out a self-administered version of PRIME-MD (Primary Care Evaluation of Mental Disorders), a questionnaire that makes Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition: Primary Care Version, diagnoses of depressive, anxiety, and somatoform disorders. After the visit, the study rheumatologists, who were unaware of the PRIME-MD results, completed a questionnaire regarding their diagnostic assessment. These patients were compared with 210 patients with musculoskeletal complaints who were cared for in a general medicine clinic. MAIN OUTCOME MEASURES: Psychiatric and rheumatic disorders. RESULTS: Compared with patients with musculoskeletal complaints in a general medicine clinic, patients referred to a rheumatology clinic had a higher prevalence of psychiatric disease (40% vs 29%; P = .008), had an almost 2-fold higher prevalence of anxiety disorders, and were more likely to have multiple psychiatric disorders (odds ratio = 2.70, 95% confidence interval = 1.50-5.00). The likelihood of a psychiatric disorder differed among patients with connective tissue disease, nonsystemic articular or periarticular disorders, and nonarticular disorders (27%, 38%, 55%, respectively; P = .006). In a best-fitting logistic regression model, psychiatric disorders markedly decreased the likelihood of a connective tissue disease (odds ratio = 0.24, 95% confidence interval = 0.09-0.62). CONCLUSIONS: Forty percent of patients referred to a rheumatology clinic in this study had a psychiatric disorder, and its presence predicted a lower likelihood of a connective tissue disease. Prospective studies are needed to determine if screening for psychiatric disease before referring patients with unexplained musculoskeletal complaints would reduce costs or improve recognition of potentially treatable psychiatric disorders.  相似文献   
955.
OBJECTIVES: Our purpose was to assess the potential for an external vaginal antiitch cream (20% benzocaine, 3% resorcinol) to significantly increase levels of methemoglobin above normal in healthy women. STUDY DESIGN: Fifty-five women reporting external vaginal itch were recruited for the study. Each patient was used as her own control with methemoglobin levels being measured before and after use of the cream. Women were instructed to apply a 1-inch strip of cream by fingertip to the external genital area three or four times a day for 7 consecutive days. RESULTS: There were no significant differences in methemoglobin levels before and after use or in levels from a subgroup of women aged > 50 years compared with levels in a younger population. CONCLUSIONS: This preparation appears to be safe when used as directed; however, the results cannot be extrapolated to the very young. Nevertheless, lavish or frequent application over wide areas of excoriation might lead to toxic concentrations and methemoglobinemia. Therefore patients with serious vaginal disease should be advised against self-treatment beyond the 7-day limit imposed by the Food and Drug Administration for over-the-counter external analgesic medications.  相似文献   
956.
Patients infected by the human immunodeficiency virus are predisposed to many infectious and noninfectious complications and often receive a variety of drugs. Furthermore, they seem to have a particular susceptibility to idiosyncratic adverse drug reactions. It is therefore surprising that only a few cases of the neuroleptic malignant syndrome have been described in patients with the acquired immunodeficiency syndrome. A high index of suspicion is required to diagnose the neuroleptic malignant syndrome in these patients, as its usual manifestations, including fever and altered consciousness, are frequently attributed to an underlying infection.  相似文献   
957.
958.
Proliferation of human CD4+ alphabeta T cells expressing a natural killer cell activating receptor (NKAR) has been shown to be enhanced, particularly in response to low doses of antigen, if the target cells present appropriate human class I major histocompatibility complex (MHC) molecules. Here, we show that NKAR also enhance proliferation and killing of target cells by subsets of CD8+ alphabeta and CD8+ gammadelta T cells, as well as by NK cells. Strikingly, interferon gamma secretion from all of these types of lymphocytes was markedly increased by interaction of the NKAR with their MHC class I ligands, independently of enhancement of proliferation. Thus, the recognition of class I MHC molecules by NKAR on both T cells and NK cells may provide a regulatory mechanism that affects immune responses through the secretion of interferon gamma and possibly other cytokines. It represents a signal for cytokine secretion alternative and/or augmentative to that through the T cell receptor.  相似文献   
959.
Occupational respiratory diseases have been reported following exposure to metal working fluids. We report a spectrum of respiratory illnesses occurring in an outbreak in 30 workers of an automobile parts engine manufacturing plant. Workers presented with respiratory complaints and, after clinical and laboratory evaluations, were classified as those having hypersensitivity pneumonitis, occupational asthma, or industrial bronchitis, or those without occupational lung disease. Hypersensitivity pneumonitis affected seven workers, with six exhibiting serum precipitins to Acinetobacter Iwoffii. Occupational asthma and industrial bronchitis affected 12 and six workers, respectively. Oil-mist exposures were below current recommendations. Gram-negative bacteria, but no fungi, Thermophiles, or Legionella, were identified. Although specific agents responsible for each individual case could not be identified, probably both specific sensitizing agents and non-specific irritants from metal working fluids, additives, or contaminants contributed to this spectrum of occupational respiratory illness.  相似文献   
960.
We report the crystal structure of Thermus aquaticus DNA polymerase I in complex with an inhibitory Fab, TP7, directed against the native enzyme. Some of the residues present in a helical conformation in the native enzyme have adopted a gamma turn conformation in the complex. Taken together, structural information that describes alteration of helical structure and solution studies that demonstrate the ability of TP7 to inhibit 100% of the polymerase activity of the enzyme suggest that the change in conformation is probably caused by trapping of an intermediate in the helix-coil dynamics of this helix by the Fab. Antibodies directed against modified helices in proteins have long been anticipated. The present structure provides direct crystallographic evidence. The Fab binds within the DNA binding cleft of the polymerase domain, interacting with several residues that are used by the enzyme in binding the primer:template complex. This result unequivocally corroborates inferences drawn from binding experiments and modeling calculations that the inhibitory activity of this Fab is directly attributable to its interference with DNA binding by the polymerase domain of the enzyme. The combination of interactions made by the Fab residues in both the polymerase and the vestigial editing nuclease domain of the enzyme reveal the structural basis of its preference for binding to DNA polymerases of the Thermus species. The orientation of the structure-specific nuclease domain with respect to the polymerase domain is significantly different from that seen in other structures of this polymerase. This reorientation does not appear to be antibody-induced and implies remarkably high relative mobility between these two domains.  相似文献   
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