Search PubMed⌕ Search

Biomedical subjects

C Chen

Publications and source records attributed to C Chen.

At least 1,351 records · Page 75Linked to original sources
PubMed1968

Detection and incidence of specific species of spoilage bacteria on fish. II. Relative incidence of Pseudomonas putrefaciens and fluorescent pseudomonads on haddock fillets.

Pseudomonas putrefaciens has been found to constitute one of the major species of spoilage bacteria on haddock fillets. The initial population of this organism on fillets of high bacterial quality is uniformly below 4% and most frequently no greater than 1%. During refrigerated storage, the organism increases at a more rapid rate than the total psychrophilic population, comprising 50 to 90% of the total population when the total count exceeds 10(6)/g of tissue. Fluorescent pseudomonads were shown to constitute a second group of predominant pseudomonads constituting up to 19.3% of the total population after 8 days of refrigerated storage. Of a total of 45 fluorescent pseudomonads isolated from haddock fillets, 14 (31.1%) were found to be potent fish spoilers. The use of a soft-agar-gelatin plating technique showed a parallel increase of proteolytic organisms with total count indicating that proteolytic organisms other than P. putrefaciens and fluorescent pseudomonads increase at a slower rate than these two groups.

Bacteriological Techniques↗
PubMedDate not supplied

Microcalorimetric study of the toxic effect of selenium on the mitochondrial metabolism of Cyprinus carpio liver.

The metabolic thermograms and heat output of mitochondria isolated from carp liver have been determined by using an LKB bioactivity monitor. The thermogram can be divided into four parts: the lag phase, active recovery phase, stationary phase, and decline phase. The thermokinetic equation was established for the active recovery and decline phase of metabolism as follows: dP/dt = k(m)P (1-SP). The rate constants k1 and k2 of two phases of active recovery and decline phase have been also calculated. The metabolism activity of mitochondrial inhibited by a high concentration of trace element selenium has been studied. The metabolic heat released, time of each phase, and rate constants can be significantly influenced by excess of selenite added. These results suggested that a high concentration of selenium can damage the structure and function of mitochondria, and thus influence their metabolism.

Animals↗
PubMedDate not supplied

Substance abuse among psychiatric inpatients.

The drug use history was obtained for all patients admitted to the inpatient service of a large municipal hospital during a 1-month period. A total of 104 patients were evaluated. An inverse relationship was found between the frequency of drug use and the diagnosis of schizophrenia. Approximately one third of the patients were found to be polydrug users, that is, individuals who used at least two types of drugs weekly (e.g., alcohol plus cocaine, heroin plus cocaine, etc.) during the 3 months prior to hospitalization. Most of the polydrug users were males. Patients who scored high in drug use tended to be younger, had more seclusions while on the ward, and had less of a history of drug or alcohol treatment. The drug having the highest frequency of daily use was found to be cocaine. It appears that drug use in general and polydrug use in particular is increasing among psychiatric patients.

Adult↗
PubMedDate not supplied

Ca2+ currents of fast blue-labeled superior cervical ganglion neurons.

To investigate if Ca2+ currents of acutely isolated superior cervical ganglion (SCG) neurons are altered after dye labeling or ultraviolet (UV) exposure, SCG neurons were labeled by multiple injections of 2% fast blue (FB) (5-microliters total) into the submaxillary gland. Ca2+ currents of both labeled and unlabeled neurons were significantly depressed by 2-min exposure to UV, compared to labeled and unlabeled neurons not exposed to UV. The I-V curve of labeled neurons was shifted hyperpolarized after UV exposure. Tail-current activation curves of both labeled and unlabeled neurons were fitted to a double Boltzmann equation. In labeled neurons, 2-min exposure to UV produced a significant reduction of the amplitude of the more depolarized component as well as a hyperpolarizing shift of the half activation potential of both components of the activation curve. However, the short time (< 10 s) required to identify a target-specific neuron had no significant effect on the biophysical properties of Ca2+ currents of FB-labeled SCG neurons. Thus, use of this label in combination with the patch-clamp technique comprises a powerful approach to study membrane currents of target-specific neurons.

Amidines↗