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81.
A simplified irrigation/aspiration system has been developed by the author in cooperation with the Klein company of Heidelberg. The suction is produced by connecting the instrument to a commonly used aspirator. The aspiration force is regulated by means of a foot-pedal, which regulates the amount of "bypass air" delivered through a special tube connected to the irrigation/aspiration handpiece. This simple i/a system represents a low-priced alternative to other systems already on the market.  相似文献   
82.
Various studies were conducted to evaluate the effects of timolol, an S-enantiomer, relative to its R-enantiomer upon intraocular pressure and related ocular systems in the rabbit. The R-enantiomer was about one-third as potent as timolol in displacing3H-dihydroalprenolol binding to iris-ciliary body tissue, reducing aqueous humor formation, and lowering intraocular pressure of -chymotrypsin hypertensive eyes. In contrast, the R-enantiomer was 50 to 90 times less potent than timolol in antagonizing the effects of isoproterenol on pulmonary and atrial -adrenergic receptors. The data indicate that the R-enantiomer may lower intraocular pressure in man at concentrations less likely than timolol to block extraocular -adrenergic receptors. Finally, to account for the differential effect of the R-enantiomer upon ocular as opposed to extraocular -adrenergic receptors, it is tentatively suggested that this agent may also act upon a population of ocular -adrenergic receptors showing relatively poor stereoselectively.  相似文献   
83.
Foodborne illness source attribution is foundational to a risk-based food safety system. We describe a method for attributing US foodborne illnesses caused by nontyphoidal Salmonella enterica, Escherichia coli O157, Listeria monocytogenes, and Campylobacter to 17 food categories using statistical modeling of outbreak data. This method adjusts for epidemiologic factors associated with outbreak size, down-weights older outbreaks, and estimates credibility intervals. On the basis of 952 reported outbreaks and 32,802 illnesses during 1998–2012, we attribute 77% of foodborne Salmonella illnesses to 7 food categories (seeded vegetables, eggs, chicken, other produce, pork, beef, and fruits), 82% of E. coli O157 illnesses to beef and vegetable row crops, 81% of L. monocytogenes illnesses to fruits and dairy, and 74% of Campylobacter illnesses to dairy and chicken. However, because Campylobacter outbreaks probably overrepresent dairy as a source of nonoutbreak campylobacteriosis, we caution against using these Campylobacter attribution estimates without further adjustment.  相似文献   
84.
85.
The tumor immune microenvironment of oral tongue squamous cell carcinoma may be accountable for differences in clinical behavior, particularly between different age groups. We performed RNA expression profiling and evaluated tumor infiltrating lymphocytes (TILs) and their T-cell subsets in order to assess the functional status of oral tongue squamous cell carcinoma tumor microenvironment and detect potentially clinically useful associations. Archival surgical pathology material from sixteen oral tongue squamous cell carcinoma patients was microscopically evaluated for TIL densities. RNA was extracted from macrodissected whole tumor sections and normal controls and RNA expression profiling was performed by the NanoString PanCancer IO 360 Gene Expression Panel. Immunostains for CD4, CD8 and FOXP3 were evaluated manually and by digital image analysis. Oral tongue squamous cell carcinomas had increased TIL densities, numerically dominated by CD4 + T cells, followed by CD8 + and FOXP3 + T cells. RNA expression profiling of tumors versus normal controls showed tumor signature upregulation in inhibitory immune signaling (CTLA4, TIGIT and PD-L2), followed by inhibitory tumor mechanisms (IDO1, TGF-β, B7-H3 and PD-L1). Patients older than 44 years showed a tumor microenvironment with increased Tregs and CTLA4 expression. Immunohistochemically assessed CD8% correlated well with molecular signatures related to CD8 + cytotoxic T-cell functions. FOXP3% correlated significantly with CTLA4 upregulation. CTLA4 molecular signature could be predicted by FOXP3% assessed by immunohistochemistry (R2 = 0.619, p = 0.026). Oral tongue squamous cell carcinoma hosts a complex inhibitory immune microenvironment, partially reflected in immunohistochemically quantified CD8 + and FOXP3 + T-cell subsets. Immunohistochemistry can be a useful screening tool for detecting tumors with upregulated expression of the targetable molecule CTLA4.Electronic supplementary materialThe online version of this article (10.1007/s12105-020-01229-w) contains supplementary material, which is available to authorized users.  相似文献   
86.
The popular and scientific understanding of acquired immunodeficiency syndrome (AIDS) in the United States has been shaped by successive historical constructions or paradigms of disease. In the first paradigm, AIDS was conceived of as a "gay plague," by analogy with the sudden, devastating epidemics of the past. In the second, AIDS was normalized as a chronic disease to be managed medically over the long term. By examining and extending critiques of both paradigms, it is possible to discern the emergence of an alternative paradigm of AIDS as a collective chronic infectious disease and persistent pandemic. Each of these constructions of AIDS incorporates distinct views of the etiology, prevention, pathology, and treatment of disease; each tacitly promotes different conceptions of the proper allocation of individual and social responsibility for AIDS. This paper focuses on individualistic vs collective, and biomedical vs social and historical, understandings of disease. It analyzes the use of individualism as methodology and as ideology, criticizes some basic assumptions of the biomedical model, and discusses alternative strategies for scientific research, health policy, and disease prevention.  相似文献   
87.
The U.S. Fish and Wildlife Service periodically determines concentrations of organochlorine chemicals in freshwater fish collected from a nationwide network of stations as part of the National Contaminant Biomonitoring Program (NCBP, formerly a part of the National Pesticide Monitoring Program). From late 1984 to early 1985, a total of 321 composite fish samples were collected from 112 stations and analyzed for organochlorine chemical residues. The mean concentrations of total DDT did not change from 1980–81 to 1984, following a period of steady decline through the 1970's; however, the mean concentrations ofp,p-DDT declined significantly. The most persistent DDT homolog (p,p-DDE) was detected at 98% of the stations sampled in 1984, and constituted 73% of total DDT residues, up from 70% in 1974–79. Collectively, these findings indicate a low rate of influx and continued weathering of DDT in the environment. Residues of polychlorinated biphenyls (PCBs) also remained widespread, but a significant downward trend in total PCBs was evident, and early eluting PCB components were present at fewer stations than in the past. Mean concentrations of dieldrin have not changed since 1978–79; concentrations remained highest in Hawaii and in the Great Lakes. Toxaphene concentrations declined from 1980–81 to 1984, especially in the Great Lakes, and the incidence of toxaphene declined from 88% of the stations sampled in 1980–81 to 69% in 1984. Mean chordane concentrations did not change from 1980–81 to 1984, following a period of decline; however,trans-nonachlor replacedcis-chlordane as the most abundant component, suggesting a lower influx of chlordane to the aquatic environment. Residues of other organochlorines—mirex, pentachloroanisole (PCA), benzene hexachloride (BHC) isomers, endrin, heptachlor, hexachlorobenzene (HCB), and Dacthal® (DCPA)—were either found at relatively few (<25%) of the stations sampled in 1984 or were characterized by relatively low concentrations. In general, organochlorine concentrations were lower in 1984 than at any time reported previously.  相似文献   
88.
Frontal polymerization (FP) has attracted increasing interest in recent years in various applications. This polymerization method can be very promising for the polymerization of thick materials with high fillers content in the range of 50–80% (weight) by local application of a reasonable amount of energy. In this work, recent advances in controllable and predictive behavior for photoinduced frontal photopolymerization are reported. Here, tert-butyl peroxybenzoate (Luperox-P) is selected to initiate thermal polymerization at depth because its high polymerization ability and its decomposition temperature is in a promising range, i.e., neither extremely high (monomer decomposition) nor very low (storage stability issues). Thermal imaging experiments are used to follow the temperatures in the samples in real time. The number of cured layers and the depth of cure are also determined. This paper investigates various factors such as the contents of both photo and thermal initiators, the light intensity, the fiber contents, the irradiation time, etc., resulting in a statistical design of experiments with the factors: 1) content of Luperox P and 2) the irradiation time used to investigate the influence on photoinduced frontal polymerization. Markedly, FP appears to be fully controllable for a storage-stable, tunable 1K system.  相似文献   
89.
This paper provides a characterization of the phonological system of a family of specifically language-impaired (SLI) individuals. Morphological and syntactic data from these same subjects have previously been presented in Gopnik and Crago (1991) and Guilfoyle (1991). Data were collected from eight subjects, all family members, ranging from 7 to 46 years of age. Language samples were obtained at two sessions, 17 months apart, and analysed according to a revised version of the phonological assessment procedures outlined in Ingram (1981, 1989). Results indicated that these SLI subjects acquired the phonological inventory of English following the normal developmental sequence, but at an extremely delayed rate. In contrast, these subjects never achieved adult competency in reproducing the complex syllable patterns of English, as evidenced by the fact that consonants in syllable-final position and clusters were particularly susceptible to deletion or substitution errors. It is argued that these data are consistent with a linguistically based account of this impairment, which is manifested in the phonological component by the inability to construct learned, language-specific rules.  相似文献   
90.
Background: Endogenous posterior uveitis (PU) can be associated with systemic diseases, and certain forms have strong association with HLA antigens. Much less is known regarding intermediate uveitis (IU). The purpose of this study was to determine whether IU is associated with the HLA system and whether it can be associated with systemic symptoms.Methods: In 179 consecutive patients consulting for uveitis, a detailed history was obtained and a physical examination performed. HLA typing for 71 HLAA, B, DR and DQ antigens, laboratory tests, and radiography of the chest, sinuses, and sacroiliac joints were systematically performed.Results: Thirty-two patients (18%) had IU; 51 (28.5%) had PU and constituted our internal control group. Nine of the patients with IU (28%) had the HLA-A28 antigen, compared with 8.1 % of a healthy control population and 8.6% of the patients with PU (P < 0.001). An associated disease was found in four patients with IU (12.5%) (none was HLA-A28) and in 45% of the patients with PU (P < 0.01). Some 67% of HLA-A28 patients with IU had arthralgias affecting the knee(s), compared with 17% of non-HLA-A28 patients and 18% of patients with PU (P<0.05 and P<0.01 respectively); 55% had gonalgias and hypocomplementemia compared with 9% and 2% respectively (P < 0.01 and P < 0.001).Conclusions: IU is significantly associated with HLA-A28; patients having this antigen may represent a subset of the disease characterized by an increased prevalence of arthralgias and hypocomplementemia.  相似文献   
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