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Biomedical subjects

W Zhou

Publications and source records attributed to W Zhou.

At least 451 records · Page 25Linked to original sources
PubMed1991

[Surgical treatment of carcinoma of the hypopharynx and cervical esophagus: substitution by the colon and stomach].

Thirty-one cases with hypopharyngeal carcinoma and 4 cases with esophageal carcinoma in cervical segment were treated surgically from April 1984 to April 1989. In 6 cases, while preserving the larynx, the hypopharynx and the esophagus were resected and reestablished by the colon. In 29 cases, total laryngectomy was also performed and 4 had their hypopharynx and esophagus substituted by the colon and 25 by the stomach. According to UICC (1982), there were 11 cases in stage II, 15 in stage III and 9 in stage IV. The mean 3-year and 5-year survival rates were 62% and 32% respectively. In fatal cases, 4 cases had recurrences at the site of pharyngeal anastomoses and 11 had metastases in the neck.

Adult↗
PubMed1991

[Pigmentary glaucoma and capsular glaucoma--a clinical and histopathological report].

In this paper, 7 cases (13 eyes) of pigmentary glaucoma and 9 cases (12 eyes) of capsular glaucoma were reported. Pigmentary dispersion in pigmentary glaucoma, pseudo-exfoliation material deposition in capsular glaucoma were the classical characteristics in the anterior segment of the eye, but pigmentary scatter was another clinical feature of capsular glaucoma. The histopathological studies of the trabeculectomy specimens by the light and transmission electron microscopy demonstrated that pigment granules or/and pseudo-exfoliation materials played an important role in obstructing the outflow tract of aqueous humor. In addition, we also discuss the diagnosis and differential diagnosis of both types of glaucoma.

Adult↗
PubMed1991

[Relation between the DNA content in laryngeal cancer cell and its clinical behaviour].

The DNA contents of 45 cases of laryngeal cancer have been analyzed by flow cytometry (FCM). The DNA index (DI) ranged from 0.9 to 3.39; proliferative index (PI) was 27.3%. Among them, 13 cases (28.8%) were diploid and 31 (68.8%) distinctly aneuploid. Correlation has been found between DI and the histopathologic grades of the tumors. The larger the DI, the higher the histopathologic grade (P less than 0.05). The mean value of the PI in supraglottic types was higher than that of glottic types. DNA content analysis also showed that diploid tumor had a better prognosis and longer survival than those with higher DI values. In addition, the proliferative activity of cancer cell was found to be markedly reduced after irradiation which demonstrates that preoperative radiotherapy is favourable for laryngeal cancer.

Aneuploidy↗
PubMed1990

On-line high-performance liquid chromatography for the determination of cephalosporin C and by-products in complex fermentation broths.

A fully automated high-performance liquid chromatographic system was developed for optimization of cephalosporin C production. Using a simple, isocratic, reversed-phase method, cephalosporin C, deacetylcephalosporin C, deacetoxycephalosporin C, penicillin N, methionine and its decomposition product 2-hydroxy-4-methylmercaptobutyric acid were determined. The method worked reliably for 250 h and supplied information on the influence of many parameters of the process.

Cephalosporins↗
PubMed1990

LHRH and GTP-gamma-S modify calcium current activation in bullfrog sympathetic neurons.

LHRH (chicken II luteinizing hormone-releasing hormone) partially reduces calcium currents and slows the activation kinetics of part of the remaining current in frog sympathetic neurons. The effects of LHRH are mimicked by intracellular dialysis with GTP-gamma-S. A strong depolarization can temporarily reverse the effects of LHRH or GTP-gamma-S: activation kinetics return to normal, and the amplitude of the current is increased (facilitation). Facilitation develops rapidly (tau = 4-6 ms at greater than +30 mV) and decays more slowly (t 1/2 = 60 ms at -80 mV). Tail currents in LHRH are smaller and faster than in the control, and these effects are partially reversed by facilitation. These results can be explained by a model in which a fraction of the channels is shifted into a "reluctant" gating mode, where opening requires stronger depolarization. If this mechanism is at the root of presynaptic inhibition, our results predict that inhibition of transmitter release would be overcome during bursts of high frequency activity.

Animals↗
PubMed1990

Protective effect of danshen during myocardial ischemia and reperfusion: an isolated rat heart study.

The effect of Danshen (Radix salviae miltiorrhizae) on mechanical activity and coronary flow rate of isolated rat hearts was examined to assess the ability of Danshen to protect the myocardium against the effects of ischemia and reperfusion. After 20 min of control perfusion, in the presence or absence of Danshen, the hearts were made totally ischemic for 30 min and then reperfused for 30 min. Danshen had a negative inotropic effect and caused an increase of coronary flow rate. During post-ischemic reperfusion recovery of left ventricular developed pressure in the Danshen-treated hearts was significantly better and contracture was significantly less than in the untreated hearts. The results indicate that Danshen protects the heart against some of the deleterious effects of ischemia and reperfusion.

Angina Pectoris↗
PubMed1990

Retinitis pigmentosa associated with glaucoma--clinical analysis.

A clinical analysis of Retinitis Pigmentosa (RP) was made in 2,789 eyes of 1,400 patients seen over a 5 year period (1983-1987), 64 eyes of 32 cases (2.3%) of RP associated with glaucoma were investigated. Of these 32 cases, the angle closure glaucoma was much more than the open angle glaucoma (30/2). More than half of the 32 cases were without cupping of disk, 5 cases did not have the glaucomatous damage to disk in spite of persistent elevated intraocular pressure for 0.5-5 yrs under the maximum medical therapy. 31 cases (97%) had subnormal blood pressure compared with the normal blood pressure value in different age groups. Histopathologic changes of the trabecular meshwork (TM) of 14 eyes showed a little bit more pigment cells in the TM than normal subjects, no typical features that would obstruct the outflow channels.

Adolescent↗
PubMed1990

[Pancreatic glucagon receptor radioassay with liver cell plasma membrane in normal and streptozotocin-induced diabetic rats].

Pancreatic glucagon receptor radioassay has been developed with rat liver cell plasma membrane prepared with sucrose gradient centrifugation. 125I-glucagon was prepared in this laboratory and the separation of B/F was done by low speed centrifugation with addition of PEG (W/V, 20%) and normal human serum. The specific binding of 125I-glucagon was 25%-35% and nonspecific binding was less than 5%. Reproducibility within and between- assay was 6.83% and 8.40% (CV%), respectively. Binding characteristics of glucagon receptor of normal and streptozotocin-induced diabetic rats were determined by using two methods, receptor dilution and conventional competitive binding assay. The results showed that there were no marked differences concerning high and low binding affinities between normal and diabetic rats, but the concentration of binding sites for both high and low affinity receptors was significantly higher for diabetic rats than normal rats. The possible mechanisms for the above results have been discussed.

Animals↗
PubMed1990

[Computer study of pathologic factors influencing survival in colorectal carcinoma--a multivariant stepwise discriminant analysis].

Five quantitative pathologic parameters and three clinicopathologic parameters in 80 colorectal carcinoma patients with different prognosis were studied with a multivariant stepwise discriminant analysis on computer. The results showed that DNA index (DI), nucleocytoplasmic ratio (NCR), histologic grade and Dukes' stage were significant factors influencing the survival. With these factors, a 4-variable Fisher's discriminant function was established, which could correctly identify 81.25% and 83.75% of the predicted cases (Jacknife Procedure and Reclassification) Sensitivity of the two methods was 87.80%. The results indicate that the multivariant stepwise discriminant analysis on quantitative pathologic parameters combined with clinicopathologic parameters is of value in predicting prognosis of colorectal carcinoma patients.

Adenocarcinoma↗
PubMed1990

[The relationship of structure in vivo of low tension glaucoma and myopia].

The structure in vivo and incidence of myopia on thirty patients with low tension glaucoma were studied in this paper. Results showed that the incidence of high myopia of patients with low tension glaucoma was higher than normal. All of the mean values of the thickness of lens, the length of vitreous and axis, and the area of optic disc were larger than normal too. These indicate that patients with low tension glaucoma may often be associated with high myopia, and their structure of eye in vivo differs from normal. These may be related to pathogenesis of disease with low tension glaucoma. The relationship of myopia and structure of optic disc with glaucoma were briefly summarized.

Adult↗
PubMed1990

Comparison of particulate 3,3',5,5'-tetramethylbenzidine and 3,3'-diaminobenzidine as chromogenic substrates for immunoblot.

In horseradish peroxidase (EC: 1.11.1.7)-dependent immunoblot assays, particulate 3,3',5,5'-tetramethylbenzidine (TMB) is shown to be a more efficient immunoblot substrate than the standard substrate 3,3'-diaminobenzidine (DAB), because TMB is easily prepared, stable, and less carcinogenic than is DAB. Assays of antibody in a serially diluted human immunodeficiency virus (HIV) control serum (CDC reference CAT# VS2151) have the same sensitivity limits with both DAB and TMB (1:312,500). Complete, working substrate solutions of H2O2/TMB/enhancer and of H2O2/DAB were stored at room temperatures and at 48 degrees C respectively. Periodic tests showed the TMB substrate system to be functional after four weeks at 48 degrees C and after eight weeks at room temperature, while the DAB system was functional after one week at 48 degrees C and after four weeks at room temperature. The stability, safety, and convenience of the commercially available TMB kits make this substrate ideal for immunoblot tests.

3,3'-Diaminobenzidine↗
PubMed1990

[Further observation on the ultrastructural characteristics of Trichomonas vaginalis].

In longitudinal sections, T. vaginalis visualized by TEM was round or ovoid with an ovoid nucleus situated close to the anterior one-third of the body. There was an independent and well-developed Golgi complex dorsal to the nucleus and parabasal filaments. The anterior end of the cell had a blepharoplast complex which consisted of three parts, i.e., periflagellar canal, C-shaped structure of the pelta in the wall of periflagellar canal and five blepharoplasts. Four anterior flagella and one posterior flagellum were extended respectively from each of the blepharoplasts, simultaneously with one costa and two parabasal filaments. The axostyle was divided into three parts, i.e., capitulum, trunk and caudal. The spoon-shaped axostylar capitulum originated from the peltar-axostylar junction was composed of many microtubules and extended around the side of the nucleus posteriorly and turned itself at the end of the nucleus forming an axostylar trunk which projected externally in the form of a spicule.

Animals↗
PubMed1989

[Measurement of the anterior chamber depth with the slitlamp and the keratometer].

A simple and accurate formula for the measurement of the anterior chamber depth with keratometer and slitlamp is described. The calculation takes into consideration the curvature of the anterior corneal surface and the refractive index of the aqueous. The method was tested with a model of anterior chamber double-blindly and proved accurate and reliable. The average anterior chamber depth of 50 patients (100 eyes) measured by this method was 2.97 +/- 0.22 mm.

Adolescent↗
PubMed1988

Effect of A-nor steroids and oestradiol on progesterone production by human luteal cells.

Cell suspensions were prepared from human corpora lutea obtained during the mid-luteal phase. Progesterone production was assessed after short-term incubation of luteal cell suspensions. Luteal cells were very sensitive to hCG, the concentration required for 50% maximum response being 0.01 i.u./ml, and the response was 5 times higher than the basal production. Oestradiol (1-100 microM) induced a significant dose-related decrease in both basal and hCG-stimulated progesterone production. The A-nor steroidal compounds anordrin and AF-45 reduced hCG-stimulated progesterone production only at the high concentration of 100 microM. The ED50 values were approximately 3 microM, 75 microM and 100 microM for oestradiol, AF-45 and anordrin respectively. Anordrin showed no significant effects on basal progesterone production. In addition, oestradiol markedly inhibited the activity of 3 beta-hydroxysteroid dehydrogenase in luteal cells, expressed by the conversion of pregnenolone to progesterone, but the inhibitory effects of anordrin and AF-45 were negligible or relatively low. The effects of anordrin and AF-45 were different from those of oestradiol on progesterone production by human luteal cells in vitro, indicating that neither substance is likely to be a useful luteolytic agent in women.

Cells, Cultured↗