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Biomedical subjects

G Xu

Publications and source records attributed to G Xu.

At least 289 records · Page 16Linked to original sources
PubMed1998

[Complications of nasal endoscopic surgery].

OBJECTIVE: To study the classification, incidence, mechanism and prevention of complications of nasal endoscopic surgery. METHODS: Sixty-two complications among 1,089 cases of nasal endoscopic surgery between February 1991 and October 1995 were analyzed. RESULTS: The types of complication included blindness (n = 1), retrobulbar hemorrhage (n = 1), inflammatory mass in orbit (n = 2), CSF (n = 2), nasolacrimal duct injury (n = 2), nasal septum perforation (n = 2), hemorrhage (n = 3), periorbital emphysema or ecchymosis (n = 14) and adhesion (n = 35). The total incidence was 5.7%, the incidence of major complications was 1.2% and minor complications 4.5%. CONCLUSION: The classification, estimation, mechanism and prevention of complications of nasal endoscopy were discussed, care should be taken to avoid the occurrence of complications and it is important to find and treat complications timely and accurately.

Adolescent↗
PubMed1998

[Ultrasonographic diagnosis of peritoneal mesothelioma].

OBJECTIVE: To investigate the sonographic features of peritoneal mesothelioma and its relationship with the gross pathology. METHODS: The ultrasonographic results of 14 cases with peritoneal mesothelioma were summarized, the sonographic features were compared with the gross pathology. RESULTS: With ultrasound examination a sheetlike mass was seen in two patients and a localized irregular mass was seen in one. Involvement of "cakelike omentum" was present in five. Pelvic mass was seen in eight and two were also with abdominal mass; one presented abdominal mass only. Bowel adhesion was found in one. Ascites was presented in all patients except one. CONCLUSIONS: It is possible for ultrasonography to suggest the diagnosis of peritoneal mesothelioma, when the sheetlike or irregular mass of peritoneum was founded. Ultrasound guided biopsy was helpful in diagnosis of peritoneal mesothelioma before operation.

Adult↗
PubMed1998

[The methods of surgical removal of glioblastoma multiform under functional cerebral cortex].

OBJECTIVE: To find the superlative way of surgical removal of glioblastoma multiform under functional cortex by comparative study of 123 patients. METHOD: Surgical approaches include direct and total resection of tumors, trans-functional cortex or adjacent area beyond functional cortex. They were compared with partial tumor resection plus external/internal decompressive procedure, total removal of tumor plus functional cortex resection. Comprehensive analysis was made. RESULT: Total removal of tumors both trans-functional or adjacent cortex prolonged the survival time of patients. As a result, minimal damage was observed in patients with both approaches, which are helpful for recovery of impaired cerebral function. On the other hand, partial resection of tumors in spite of combining with decompressive procedure or functional cortex resection did not show the same benefit. CONCLUSION: Surgical resection of glioblastoma multiform through trans-functional cortex or adjacent cortex beyond functional area is superior to other approaches both in dealing with total tumors removal and cerebral function recovery. But the resection through adjacent cortex beyond functional area in recovery of impaired cerebral function is more effective.

Brain Neoplasms↗
PubMed1998

[Analysis of blood flow in ophthalmic arteries in patients with middle and late stages of glaucoma with Doppler sonography].

OBJECTIVE: To understand the actual blood flow in cases with middle and late stages of glaucoma and the role of vascular factor in the deterioration of visual function in such patients. METHODS: The blood flow in ophthalmic arteries was determined with color Doppler sonography (CDS) in 156 cases of patients with middle and late stages of glaucoma as well as in 75 cases of normal individuals as controls. RESULTS: The average peak systolic velocity (PSV) and end diastolic velocity (EDV) of ophthalmic artery in normal control are 35.98 +/- 9.13 cm/s and 11.98 +/- 3.90 cm/s; the PSV and EDV in primary open-angle glaucoma (POAG) group are 24.13 +/- 4.65 cm/s and 7.10 +/- 1.85 cm/s; and in primary close-angle glaucoma (PCAG) group are 22.89 +/- 5.43 cm/s and 7.06 +/- 1.92 cm/s, respectively. No significant difference was found between POAG group and PCAG group (P > 0.05). However, significant differences were shown between normal group and patients with glaucoma for both PSV and EDV (P < 0.01). CONCLUSION: The blood flow in ophthalmic arteries in patients with middle and late stages of glaucoma decreases significantly and the disorder in local blood circulation is evident, that is highly related to the deterioration of visual function and supports the vascular factor theory in the pathogenesis of glaucoma.

Adult↗
PubMed1998

[Apoptosis in age-related macular degeneration].

OBJECTIVE: To examine the role of apoptosis in photoreceptor cell death in age-related macular degeneration. METHODS: 16 human eyes with age-related macular degeneration (ARMD) were studied by histopathology and TDT-mediated biotin-dUTP nick-end labeling (TUNEL) technique. RESULT: The characteristic DNA fragmentation of apoptosis was observed in scattered photoreceptor cells in 6 of 16 eyes. CONCLUSION: It is suggested that apoptosis be one of the important pathways of photoreceptor cell death in age-related macular degeneration.

Adult↗
PubMed1998

[Advances in chromatography and related techniques in China--status report in 1996-1997].

An overview of the use of chromatography and related techniques in China is given in 1996-1997. This review includes five parts, the statistical results of the scientific papers published in 15 domestic and a few foreign periodicals which are closely related to chromatography and presented on 1997 Beijing Conference and Exhibition on Instrumental Analysis and the 11th National Symposium of Chromatography, about chromatographic theory, GC, LC and CE. One hundred thirty seven references are cited.

Animals↗
PubMed1998

[The development of SH-C1 autobiochemical analyzer].

As a miniature automatic analyzer, SH-C1 analyzer can be divided into five parts: the diluter, the circular reaction plate, the photometer, the electronic control board and the main microcomputer system with CRT monitor. The paper discusses its general structure and its key parts: the double-beam high precision photometer and the diluter controlled by microprocessors. The paper also describes the software system and the properties of the instrument.

Autoanalysis↗
PubMed1998

[Sequencing of Cyt b gene fragments and PCR identification of "jinqian baihuashe" (Bungarus parvus) and its adulterants].

DNAs extracted from both "Jinqian Baihuashe" (Bungarus parvus) and its adulterants and original animals of the crude snake drugs were used as templates for Cyt b gene fragment amplification. The sequence data of the fragments showed that the differences of the sequence between Bungarus parvus and its adulterants were far greater than that between intraspecific variations of Bungarus parvus. Therefore, the Cyt b gene fragment was a good molecular genetic marker for the authentication of Bungarus parvus. On the basis of the sequence data, a pair of specialized primers, BuL-1 and BuH-1 was designed for the PCR identification of Bungarus parvus. The effectiveness of the primers were examined at a series of anneal temperatures. The results showed that Bungarus parvus samples could be absolutely distinguished when the anneal temperatures were 60 degrees C-65 degrees C, whereas no incorrect or missing discrimination was found at these temperatures. The results also showed that the powder of Bungarus parvus which was mixed with powders of three other crude snake drugs may be detected by the PCR identification. This indicates that PCR identification may be a new method for examining the compositions of Chinese patent medicine.

Animals↗
PubMed1998

[Scanning electron microscope observation and image quantitative analysis of Hippocampi].

The "scale-like projects" on the derma of 3 species of Hippocampi, H. kuda Bleerer, H. trimaculatus Leach and H. japonicus Kaup were observed by scanning electron microscope (SEM). Results showed that some characteristics such us size, shape and type of arrangement of the "scale-like projects" can be considered as the evidence for microanalysis. Image quantitative analysis of the "scale-like project" was carried out on 45 pieces of photograph using area, long diameter, short diameter and shape factor as parameters. No difference among the different parts of the same species was observed, but significant differences were found among the above 3 species.

Animals↗
PubMed1998

[Histological studies on the roots of twelve species of Sect. Microdiscus and Sect. Adenophora of the genus Adenophora].

This paper reports the root structures of Adenophora lamarkii Fisch, A. hunanensis Nannf., A. hunanensis Nannf. subsp. huadungensis Hong, A. trachelioides Maxim., A. trachelioides Maxim. subsp. giangsuensis Hong, A. remotiflora (Sieb. et Zucc.) Miq. derived from Sect. Microdiscus of the Genus Adenophora, and A. stenanthina (Ledeb.) Kitagawa, A. stenanthina (Ledeb.) Kitagawa subsp. xifengensis P. F. Tu et Y. S. Zhou, A. liliifolioides Pax et Hoffm., A. capillaris Fisch., A. tetraphylla Fisch., A. triphylla (Thunb.) A. DC. derived from Sect. Adenophora of the Genus Adenophora. Based on the histological studies of 23 species, 5 subspecies and 2 varieties of the Genus Adenophora, a Key of histological characters is given.

Campanulaceae↗
PubMed1998

[Histological studies on the roots of eighteen species of sect. microdiscus of the genus Adenophora].

The Chinese materia medica "Nanshasheng" (Radix Adenophorae) specified in Chinese Pharmacopoeia (1995) is the dried root of Adenophora tetraphylla (Thunb.) Fisch. or A. stricta Miq. (Fam. Campanulaceae). Results of an investigation on the botanical origin of the drug showed that the roots of 30 species (subspecies, varieties) of the genus Adenophora are also used in certain districts in China. Thus, it is necessary to study and compare the histological characters of these roots. In this paper, the root structure of 18 species from Sect. Microdiscus are reported, viz. Adenophora brevidiscifera Hong, A. coelestis Diels, A. stricta Miq., A. stricta Miq. var. qinglongshanica P. F. Tu et G. J. Xu, A. stricta Miq. var. nanjingensis P. F. Tu et G. J. Xu, A. stricta Miq. subsp. henanica P. F. Tu et G. J. Xu, A. stricta Miq. subsp. sessilifolia Hong, A. longipedicellata Hong, A. gmelinii (Spreng.) Fisch., A. polyantha Nakai, A. micrantha Hong, A. stenophylla Hemsl., A. potaninii Korsh., A. bockiana Diels, A. wawreana Zahlbr., A. tricuspidata (Fisch. ex Roem. et Schult.) A. DC., A. pereskiifolia (Fisch. ex Roem. et Schult.) G. Don and A. divaricata Franch. et Sav.. According to the presence, arrangement and thickening of cell walls of sclerified cork cell (SCC) in cork tissue and the rate of secondary and anomalous structures, the histological structures of Adenophora roots are classified into types A, B and C. In type A, SCC are arranged in ring shape. Type A can be further classified into subtypes A1 and A2. Only the outer and anticlinal walls of SCC are thickened in subtype A1, and all cell walls of SCC are thickened in subtype A2. In type B, SCC are arranged scatteredly, not in ring shape. In type C, there is no SCC. Type C can be classified into subtypes C1, C2 and C3. In type C1, the secondary structure occupies more than 50% of the root diameter. In type C2, the anomalous structure is more than 50% of the root diameter, and the anomalous vascular bundles are in band form. The anomalous structure occupies more than 50% of the root diameter in subtype C3, and the anomalous vascular bundles are branched.

Campanulaceae↗
PubMed1998

[Investigation on resources and commodities of Chinese medicinal herbs of Jili].

OBJECTIVE: To make clear the current situation of application of the Chinese medicinal herbs of Jili. METHOD: The medicinal resources and commodities of the berbs in some provinces and cities in China were investigated. RESULT: The species Tribulus terrestris included in is widely distributed in China. The fruit of T. terrestris which is widely used in China as a traditional medicine is commonly called Yingjili. Being only the fruit of Atriplex entralasiatica Ruanjili is produced mainly in Shandong Province and customarily used as Fructus Tribuli in some areas of Shandong and Hebei Provinces. CONCLUSION: The current situation of medicinal application of Jili basically conforms to the requirements of . The main variety is Yingjili.

China↗
PubMed1998

[Studies on some properties of the immobilized penicillin acylase by polyacrylonitrile fibres].

The extracellular penicillin acylase from Bacillus megaterium was immobilized by coupling to derivatives of polyacrylonitrile fibres. The apparent activity of the immobilized penicillin acylase was about 2,000 u/g (dry weight). The optimal pH and temperature were 9.0 and 50 degrees C for hydrolysis of penicillin G, respectively. The immobilized enzyme was stable in the pH range of 5.5-10.3, and at the temperature below 50 degrees C. The apparent Michaelis constant Ka and Vm of the immobilization enzyme were 1.33 x 10(-2) mol/L and 2.564 mmol.min-1, respectively. The inhibition constant of phenylacetic acid acted as a competitive inhibitor for The immobilization enzyme was 0.16 mol/L. The remained activity was about 80% after operating 20 times.

Acrylic Resins↗
PubMed1998

[Spectroscopic characterization of a new terbium complex with red fluorescence].

Usually, the emission spectra of terbium complexes exhibit 490 nm, 545 nm bands (green color) under the excitation of UV light, which is ascribed to the two 5D4 - 7F6, 5D4 - 7F5 transition. In this report, pink red fluorescence under the excitation of 300-370nm UV light is observed for a new 1, 10-phenanthroline-2-naphthoate complex of terbium. The fluorescence, FT-IR, ICP and X-ray fluorescence analysis were performed. The results showed that under the perturbation of the ligands field, the probability of 5D4 - 7F3 transition of terbium ion was greatly enhanced, while the probability of 5D4 - 7F5 transition was greatly decreased in the complex. Therefore, pink-red fluorescence was observed for the title complex.

English Abstract↗
PubMed1998

[Investigation on the luminescence properties of Er ions in Er-doped sol-gel silica glasses].

Er-doped sol-gel silica glasses which have room temperature photoluminescence at 1.54 microm and doped concentration of 10(20)/cm(3) have been prepared. The examination results Indicated: (1) PL spectrum has largest intensity at the 0.5W% doped concentration; (2) the intensity of PL decreased 74%, when the temperature raised form 4K to 300K; (3) The Er ion and O ions formed complexes with coordinated numbers of 8 or 9.

English Abstract↗
PubMed1998

Phase I trial of the colloidal dispersion formulation of 9-amino-20(S)-camptothecin administered as a 72-hour continuous intravenous infusion.

The camptothecins are a class of potent cytotoxic anticancer agents that interact with the nuclear enzyme topoisomerase I to produce lethal DNA strand cleavages. 9-Amino-20(S)-camptothecin (9AC) was introduced into Phase I clinical trials in dimethylacetamide and polyethylene glycol 400 in a 10 mM phosphoric acid vehicle for i.v. solubility. A lyophilized colloidal dispersion (CD) of 9AC for reconstitution with 20% dextrose in normal saline was developed as an alternative formulation. Patients (ages 25-75 years) with normal liver and kidney function, Eastern Cooperative Oncology Group performance status < or = 2, and up to two prior chemotherapy regimens were treated. The initial infusion rate was 37.5 micrograms/m2/h as a 72-h continuous infusion (2.7 mg/m2 total dose). Patient cohorts were treated with escalating infusion rates until grade 4 hematological or other grade 3 toxicity developed. Pharmacokinetic sampling was performed on all patients, and 9AC lactone concentrations in plasma were determined by a high-performance liquid chromatographic assay. Twenty-five patients received a total of 65 courses of 9AC CD at doses from 2.70 to 4.65 mg/m2. The dose-limiting toxicity was neutropenia, with little nonhematological toxicity. Nonlinear regression analysis of pooled patient data yielded a total plasma clearance of 30.3 +/- 4.5 liters/h/m2, a half-life of 22.5 +/- 8.5 h, a mean residence time of 9.7 +/- 3.5 h, and a steady-state volume of distribution of 325 +/- 145 liters/m2. Although no objective responses were seen, 9 of 25 patients exhibited stable disease for 2-6 months. The plasma pharmacokinetics of 9AC lactone in cancer patients were comparable between the 9AC CD and soluble formulations. The dosing regimen recommended for Phase II trials of the 9AC CD formulation is 54.2 micrograms/m2/h, given as a 72-h continuous i.v. infusion every 3 weeks.

Adult↗