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1.
Reproductive problems, including congenital malformations, reduced hatching success, and decreased survival of hatchlings, have been observed in colonial-nesting water birds at the San Francisco Bay National Wildlife Refuge (SFBNWR). Twenty-four black-crowned night heron (Nycticorax nycticorax) eggs were collected from SFBNWR in 1983. Twelve of these were collected from separate nests when late-stage embryos were pipping, and an additional egg was randomly collected from each nest for organochlorine analysis. Overt anomalies and skeletal defects were not apparent. Embryonic weights (with partially absorbed yolk sacs removed) were 15% lower (p less than 0.05) in SFBNWR embryos compared to control embryos from the Patuxent Wildlife Research Center (PWRC). Crown-rump length and femur length were shorter for SFBNWR embryos. The geometric mean polychlorinated biphenyl (PCB) concentration in SFBNWR eggs was 4.1 ppm wet weight, with a range of 0.8-52.0 ppm. A negative correlation (r = -0.61; p less than 0.05) existed between embryonic weight and log-transformed PCB residues in whole eggs collected from the same nest at SFBNWR, suggesting a possible impact of PCBs on embryonic growth. A correlation with embryonic weight did not occur for DDE [1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene] residues. Liver microsomal aryl hydrocarbon hydroxylase activity was neither significantly elevated nor correlated with PCB, DDE, or PCB plus DDE log-transformed residues. It is unknown whether the apparent association between PCBs and lower weight is persistent through hatching.  相似文献   
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Many risk factors have been identified with the progression of atherosclerotic lesions. Of these hyperglycemia, hypertension, hyperlipidemia, and obesity are amenable to nutritional therapy. Minimal data exist to prove that alteration in these risk factors prevent atherosclerosis in adults and children. This paper discusses nutritional approaches to prevention of atherosclerosis in children.  相似文献   
4.
Recent years have witnessed increased antipsychotic treatment of children despite limited long‐term safety data in children. In this study, motor side effects associated with the use of antipsychotic drugs in children were examined in a sample of pediatric psychiatric patients. Child and adolescent psychiatric patients receiving antipsychotics (most were on atypicals) for 6 months or longer (n = 118) were compared with antipsychotic‐naïve patients (n = 80) with similar age, sex ratio, and diagnoses. Only 19% of patients on antipsychotics had ever experienced psychotic symptoms. Eleven children (9%) on antipsychotics exhibited dyskinesia, when compared with 0 in the naïve group (P = 0.003, Fisher's exact test). Nine of 62 African–American children (15%) on antipsychotics exhibited dyskinesia, when compared with only 4% (2 of 52) of European–American children (P = 0.003, Fisher's exact test). Children treated with antipsychotic drugs might experience a significant risk of dyskinesia even when treated only with atypical antipsychotics. Ethnicity might also be a risk factor for dyskinesia in children. Side‐effect profile of the atypical antipsychotic drugs in children may be much different than that in adults. © 2007 Movement Disorder Society  相似文献   
5.
We studied the autoantigen targets of 75 human sera that had antibodies to the nuclear envelope (NE) as identified by indirect immunofluorescence (IIF) on HEp‐2 cells. Several different IIF staining patterns could be identified when antibodies to different components of the nuclear membrane (NM) and nuclear pore complexes (NuPC) were identified: a smooth membrane pattern characteristic of antibodies to nuclear lamins, a punctate pattern typical of antibodies to the nuclear pore complex and more complex patterns that included antibodies to nuclear and cytoplasmic organelles. Western immunoblotting of isolated nuclear and NE proteins and immunoprecipitation of radiolabelled recombinant proteins prepared by using the full‐length cDNAs of the Translocated promoter region (Tpr), gp210 and p62 were used to identify specific autoantibody targets. Fifty‐two of the 75 (70%) sera bound to Tpr, 25 (33%) bound to lamins A, B or C, 15 (20%) reacted with gp210 and none reacted with p62. Sixteen (21%) did not react with any of the NE components tested in our assays. The clinical features of 37 patients with anti‐NE showed that there were 34 females and three males with an age range of 16–88 years (mean 59 years). The most frequent clinical diagnosis (9/37 = 24%) was autoimmune liver disease (ALD; two with primary biliary cirrhosis), followed by seven (19%) with systemic lupus erythematosus (SLE), four (11%) with a motor and/or sensory neuropathy, three (8%) with anti‐phospholipid syndrome (APS), two with systemic sclerosis (SSc), two with Sjögren's syndrome (SjS), and others with a variety of diagnoses. This report indicates that Tpr, a component of the NuPC, is a common target of human autoantibodies that react with the NE.  相似文献   
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Collagen production was investigated in cultured rabbit synovial fibroblasts exposed in vitro to D-penicillamine (D-Pen). The results show that these cells are rather insensitive to the drug since only a slight increase of the collagen amount secreted was observed for 48-h exposure to concentrations of 200-400 micrograms/ml. However, fibroblasts derived from the synovium of arthritic rabbits proved to be more susceptible to D-Pen, responding by a marked increase of collagen secretion even for concentrations of 50 micrograms/ml. This finding suggests that synovial fibroblasts of arthritic patients, probably stimulated by the inflammation process, could be target cells for the D-Pen action. The activities of 4-prolyl-hydroxylase (4-PH) and galactosylglucosyl-transferase (GGT) were assayed in the same cultures. A correlation has been found between the 4-PH activity and the collagen amount produced. In contrast, no alteration in the level of GGT on exposure to D-Pen was detected. Finally, D-Pen was shown to reduce in vitro the production of collagen-inhibiting factors by phytohaemagglutinin-stimulated mononuclear cells. This effect was associated with an inhibition of the release of monocyte cell factor (MCF/interleukin-1), suggesting that D-Pen could indirectly affect synovial collagen synthesis by interfering with interleukin-1 secretion.  相似文献   
8.
CD138/Syndecan-1 is a cell-surface heparan sulfate proteoglycan expressed on most epithelial cells, and decreased CD138 expression is associated with increased invasive and metastatic potential in carcinomas. CD138 expression has not been investigated previously in renal neoplasms. Formalin-fixed, paraffin-embedded tissue sections of 50 renal cell carcinomas (RCCs) (40 clear-cell RCCs of various nuclear grades, 10 of which harbored metastases; 6 papillary RCCs, 4 chromophobe RCCs) and 4 oncocytomas were stained immunohistochemically for CD138 using the monoclonal antibody B-B4 (CD138). Staining intensity and distribution were scored and results related to histologic type, nuclear grade, and local stage (pT). Immunoreactivity was membranous in all clear-cell RCCs, chromophobe RCCs, and oncocytomas and was located at the basal aspect of cytoplasm in papillary RCCs. In clear-cell RCCs, the extent of CD138 immunoreactivity decreased with increasing nuclear grade (P<0.001). No significant correlation was found between CD138 immunoreactivity and histologic type (P=0.2) or local stage (P=0.7). Metastatic foci showed a mild to moderate decrease in intensity compared with primary tumor. Decreased expression of CD138 may have a role in more aggressive behavior of clear-cell RCC.  相似文献   
9.
Objectives: The reconstructed pharyngoesophageal segment (PES) serves as the neoglottis following total laryngectomy, as it provides the source of vibration for production of tracheoesophageal puncture (TEP) voice. To date, little information exists regarding the vibratory characteristics of the PES. The purpose of this investigation was to study the anatomy and physiology of the PES using videostroboscopy. Study Design: Prospective study investigating the anatomy and physiology of the PES in 34 laryngectomees who used TEP speech as their primary form of communication. Materials and Methods: Videostroboscopy and voice recordings were graded by three trained, blinded judges using a seven-point scale. Results: The patients demonstrated differences that allowed for separation of patients into two main groups: “poor” and “effective” TEP speakers. The voice quality differences were explained by anatomic and physiologic characteristics of the PES. Redundant, thick, and dyssynchronous PES features were observed in patients with poor TEP speech skills; the effective speakers exhibited less redundant, thinner mucosa and more synchronous vibratory patterns. Moreover, the latter subgroup consistently demonstrated a greater degree of volitional PES control and less spasmodic activity than their poorly speaking counterparts. Length of the PES opening (measured in the horizontal plane) as well as amount and consistency of secretions did not appear to influence TEP speech or voice proficiency. Conclusion: Videostroboscopy in laryngectomees is a noninvasive, inexpensive, easily performed procedure that may contribute valuable information regarding the anatomy and physiology of the PES, especially in patients who experience difficulties achieving satisfactory TEP voice and speech production.  相似文献   
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