Biomedical subjects

L Chen

Publications and source records attributed to L Chen.

At least 847 records · Page 47Linked to original sources

PubMed1997

[Clinical investigation on 42 cases of pulmonary tuberculoma].

OBJECTIVE: For the purpose to find the possible reasons causing pulmonary tuberculoma been misdiagnosed as lung cancer. METHODS: Clinical symptoms, chest X ray films, tomographic and CT manifestations as well as laboratory data of 42 cases of pulmonary tuberculoma pathologically proved were thoroughly reviewed. All the radiological appearances were compared with pathological findings. RESULTS: Shallow lobulated contour, spurlike shadow formation, vacoule sign, satellite lesions, pleural involvement, calcified spots were found very important for differential diagnosis of these 2 diseases. CONCLUSIONS: It is difficult to differentiate pulmonary tuberculoma from lung cancer. By paying special attention to the above mentioned appearance, evaluating them very carefully and considering them with positive laboratory findings, it might be possible to avoid misdiagnosis before surgical operation.

Adult↗

PubMed1997

[Nitric oxide, TNF-alpha and IL-8 in cerebrospinal fluids of tuberculous and cryptococcic meningitis].

The contents of NO, TNF-alpha and IL-8 in the cerebrospinal fluids (CSF) of patients with tuberculous and cryptococcic meningitis were detected. The results showed that the concentration of NO2-/NO3- and the levels of TNF-alpha and IL-8 in CSF of the two kinds of meningitis were higher than those of normal CSF, and the concentration of NO2-/NO3- correlated positively to the content of TNF-alpha. The results indicate that the over production of NO, TNF-alpha and IL-8 in CSF may involve in the tissue inflammation and damage of central nerve system infection.

Adolescent↗

PubMed1997

[Protective effects of nimodipine on brain edema induced by pertussis bacilli in rats].

The changes of brain water content and Evan blue(EB) were investigated on the model of infection brain edema induced by Pertussis Bacilli(PB) in 72 rats. Nimodipine was admenistred to show its effect on the PB induced brain edema. The experiment results showed that the water content and EB content in the PB group were significantly increased than those normal group and normal saline group at 30 min, 4 hours and 24 hours after the injection of PB (P < 0.05). Nimodípine could significantly reduce brain water content and EB content, so that brain edema was attenuated. It indicates that nimodipine showed advantage to treatment of PB brain edema.

Animals↗

PubMed1997

Sexually transmitted diseases and risk of HIV infection in men attending a sexually transmitted diseases clinic in Dakar, Senegal.

This cross-sectional study was carried out among male outpatients with symptoms of STDs at the STD reference centre at the Institute of Social Hygiene (IHS), Dakar, Senegal, from March 1989 through May 1991. This study was used to determine the prevalence of STDs and HIV among male patients attending an STD clinic and to identify their socio-demographic characteristics and risk factors. A total of 975 patients were enrolled in the study. The most common syndromes were urethritis (76%) and genital ulcers (22%). Considering single infections, the major STD agents were Neisseria gonorrheae (N.gonorrheae, 30%), Chlamydia trachomatis (C.trachomatis, 15%), Treponema pallidum (T.pallidum, 12%), and Haemophilus ducreyi (H.ducreyi, 7%). HIV prevalence was 2.6 percent (25/975). After multivariate analysis, the risk factors associated with HIV infection were a history of sex with prostitutes (odds ratio [OR] = 8.6, 95% confidence interval [CI] = 2.0-37.8), unprotected sexual contact (OR = 5.6, 95% CI = 1.2-25.0), a history of urethritis (OR = 3.4, 95% CI = 1.3-8.9), current STDs due to H.ducreyi or T.pallidum (OR = 6.1, 95% CI = 2-18.8), and mixed STD infection (OR = 5.3, 95% CI = 1.3-21.8). HIV prevalence was quite low in this population compared to similar studies of STD patients from other sub-Saharan African countries. Neisseria gonorrheae and Chlamydia trachomatis were the leading causes of STDs. A history of risky sexual behaviour, previous STDs, current genital ulcers, and mixed STD infections were associated with HIV infection. Further studies are necessary to determine changes in the relationship of STDs and HIV infection in this population.

Adult↗

PubMed1997

[Quantitative change of glucagon and insulin immunoreactivities in the pancreas of fasting rats].

In this study, the glucagon and insulin immunoreactivities in the fasting rat pancreas were quantitated by image analysis. The results showed that the glucagon immunoreactivity significantly decreased in fasting rats and that of insulin increased, as compared with that in normal rats. The glucagon immunoreactivity significantly increased after intravenous injection of glucose but no marked difference was found in insulin. These results suggest that the A cells of pancreas may be directly stimulated by nutrients, and the B cells in a different way.

Animals↗

PubMed1997

[The method to remove nitrite from tap water by tea].

Drinking water (tap water) is polluted in pipelines by bacteria after long distance transportation. The water contains nitrite (NO2-) which is potentially harmful to human health. The nitrite concentrations range from 0.10 to 2.0 mg/L. Our experiment proved that NO2- could not be removed by boiling, but could be removed by tea. As a natural antioxidant, tea contains several antioxidants, such as ascorbic acid and catechins, which removed NO2- from tap water effectively.

Antioxidants↗

PubMed1997

[Numerical change of 7, 17 and Y chromosomes in human lung carcinoma detected by fluorescence in situ hybridization].

OBJECTIVE: To study the copy number of chromsomes 7,17 and Y in lung carcinomas. METHODS: Fluorescence in situ hybridization (FISH) was used to detect the number of above mentioned chromosomes on the touch smears of 17 cases of lung carcinoma (adenocarcinoma and squamous cell carcinoma). RESULTS: Triploid chromosome 7 FISH signals were found in 31.73% of the tumor nuclei, dipoid chromosome 17 FISH signals in 43.00% and monoploid chromosome Y FISH signals in 58.04% of these nuclei. CONCLUSIONS: The number of chromosome 7 was obviously increased in both lung adenocarcinoma and squamous cell carcinoma, and the rate of trisomy 7 was the highest. In addition, there is a significant difference in the distribution of chromosome 7 ploidy between lung adenocarcinoma and squamous cell carcinoma.

Adenocarcinoma↗

PubMed1997

[Correlation of tumor microvesseldensity with prognosis in osteogenic sarcoma].

OBJECTIVE: To investigate the relationship between tumor angiogenesis and clinical pathology, as wel as the prognosis in osteosarcoma. METHODS: Intratumoral microvessel density (MVD) in 70 cases of osteosarcoma was assessed immunohistochemically by using the specific endothelial cell markers F VIII-RA and CD31. RESULTS: There was no correlation between the MVD and the tumor size, Price's grade, as well as Dahlin's classification; however, significant correlation was found between the MVD and the neoplastic osteoid classification, new WHO classification in 1993, as well as the proliferating cell nuclear antigen (PCNA) labelling index. Microvessel counts were associated with overall survival by Kaplan-Meier analysis. An average vessal count of less than 31 (x 200) suggested a better survival, but a higher vessel count of more than 31 (x 200) showed a trand to worse the overall survival. CONCLUSION: The results suggest a significant relationship between MVD and prognosis; moreover, MVD may be a useful prognostic indicator in osteosarcomas.

Bone Neoplasms↗

PubMed1997

[An autopsy analysis on 14 cases of poisoning death caused by illegal quackery].

In this paper, 14 cases on poisoning death caused by illegal quackery were analyzed. The results indicated that the causes and routes of poisoning were various, and that there were three kinds of poisoning types in illegal quackery. Main points of forensic identification were pointed out. In addition, some medical and administrative measures and possible measures were also investigated. The authors suggest that measures as above are of great importance for preventing similar poisoning and improving forensic identification.

Aconitine↗

PubMed1997

[Cloning of genes associated with taxol-induced apoptosis of human breast cancer cells].

The method of mRNA differential display was employed to isolate expressing genes involved in taxol-induced apoptosis of human breast cancer cells (BCap 37). Results demonstrated that the expressive alteration of twelve clones isolated was associated with taxol-induced apoptosis identified by Northern blot. cDNA sequence of clone C3P3 was highly homologous (99%) to human S-adenosylmethionine (S-AdoMet) synthetase. Increased transcriptional level of clone C3P3 induced by taxol was parallel to enhanced enzyme activity of S-AdoMet synthetase. These results suggested that the expression of these clones isolated by the mRNA differential display be possibly involved in the regulation of taxol-induced apoptosis. Their function in details need further study.

Antineoplastic Agents, Phytogenic↗

PubMed1997

[The setting up of human serum calcitonin radioimmunoassay and its clinical application].

This study deals with the setting up of human serum calcitonin radioimmunoassay (hCT-RIA) using the high titer and specific antibody which was prepared by our own laboratory. The final dilution of the antibody titer was 1:1,200,000 when the binding rate of Bo/T was 30%. The antibody's affinity constant (Kd) was 2.25 x 10(11) L/M. No cross reaction was found between the antibody and the following eight different peptide hormones and proteins, viz.: TSH, T3, T4, ACTH, PTH, BGP, Insulin and Gastrin. The coefficients variation of intra and inter assay were 3.2% and 9.0%, respectively. The mean recovery rate of CT was 99.8%. The sensitivity of this assay was 9.4 pg/ml. The examination of this methodology showed that all its indices met the demands of RIA. There was no difference in the mean value of serum CT between the two sexes in 232 normal subjects, but the serum CT concentration in those aged of sixty and over of men and women, were much lower than those aged of fourty group. Mean CT concentration was low in the patients with primary osteoporosis, but were significantly higher in those suffering from medullary thyroid carcinoma, primary hyperparathyroidism crisis and chronic renal failure.

Adult↗

PubMed1997

[The expression of MLC2-chymase fusion gene in cultured neonatal myocardial cells].

A series of MLC2-chymase fusion genes consisting of nested 5' deletion of the chymase promoter region were constructed and transfected into primary cultured neonatal Wistar rat myocardial cells according to the modified calcium phosphate precipitation method. Total RNA Dot-blot hybridization and analysis of densitometric scanning demonstrated that MLC2 promoter is enough to direct human heart chymase gene transcription in cultured neonatal rat myocardial cells. The highest level of expression was found with the MLC2-chymase construct containing 6 bp of the chymase promoter region. More sequence of the chymase promoter region between MLC2 promoter and the ATG of chymase gene resulted in a subsequent decrease in the expression of human heart chymase gene.

Animals↗

PubMed1997

[Amplification and sequencing of heavy chain variable region (VH) gene of a human monoclonal antibody (CM-1) with specificity to breast cancer].

For rescueing the heavy chain variable region (VH) gene of CM-1--a human monoclonal antibody against breast cancer, total RNA was extracted from the CM-1 hybridoma cells. After preparing its cDNA by reverse transcription and amplifying by PCR, a DNA fragment with about 400 bp was obtained. With an internal primer, the fragment was directly sequenced and 344 bases which consisted well to known human antibody VH gene construction were read out. In addition, its corresponding amino acid sequences coincided with the 1-3 group canonical structure of human antibody variable region. So we suggested that CM-1 could be considered as an individual of human antibody family, and should aid the preparation of antibody molecules.

Amino Acid Sequence↗

PubMed1997

[Effect of calcium and angiotensin II receptor on angiotensin II-stimulated protein synthesis in neonatal myocardial cells].

In this study, the role of angiotensin II (Ang II) receptor, Ca2+ in the Ang II-stimulated neoeatal myocytes protein synthesis were investigated and the effect of Ang II on expression of c-fos gene was observed. The results showed that the stimulatory effect of Ang II on protein synthesis was blocked by the Ang II antagonist-[Sar1 Ile8] Ang II. When verapamil, EG-TA, dantrolene, and Fura-2/AM, were added to the medium, the 3H-leucine incorporations stimulated by Ang II were reduced by 17%, 19%, 22%, and 27%. Using calcium ionophore-A23187 did not stimulate protein synthesis, but enhanced Ang II-induced 3H-leucine incorporation. In addition, Ang II could induce expression of c-fos gene. These results indicated that the hypertrophic effect of Ang II on the myocytes was mediated by Ang II receptor and depended on increase in [Ca2+]i and may be associated with enhanced expression of c-fos.

Angiotensin II↗

PubMed1997

[Sonographic measures of the hip joint of 1328 newborns of Han and Uygur nationalities-relative factors of congenital dislocation of hip].

The four sonographic methods (Engesaeter, Terjesen, Graf, Morin-Harcke) were used for examining the hip joint of 1328 newborns of Han and Uygur nationalities. The difference between Han and Uygur newborns was not statistical significant, but some literatures reported that in our country, the incidence of different nationalities in different regions varied. Our conclusion is that there is no obvious relationship between the depth of the acetabulum and the percentage of the femoral head covered by the acetabulum. It is caused by other factors, inherent or acquired. The value of the hip joint of the male and female has significant difference (P < 0.0005). The incidence of CDH in girls is much higher than that in boys. This may be related to the different depth of the acetabulum and different percentage of the femoral head covered by the acetabulum. In the period of newborn, girl's depth of the acetabulum is smaller than that of boys.

Anthropometry↗

PubMed1997

[Antioxidative effect of constituents of herba Epimedii (ESPS)].

Herba Epimedii is a traditional Yang invigorating Chinese herb widely used in clinic. The experimental results have shown that ESPS obviously increases superoxide dismutase(SOD) activity of red cells and liver in aged mice and rats, and increases glutathione peroxidase(GSH-Px) activity of red cells in aged mice. On the other hand, ESPS obviously helps to reduce the content of serum and liver lipoperoxide(LPO) in aged mice and rats, as well as the content of lipofuscin(LF) in cardiac muscle of aged mice. The results suggest that being helpful in increasing SOD and GSH-Px activities and inhibiting the formation of LPO and LF, ESPS may be a good antiageing agent.

Aging↗

PubMed1997

[The application of D1S80 locus analysis to forensic problems by using Amp-FLP technique].

This is a paper on paternity testing in 85 test cases and the identification of individuals from mixed stains of semen and vaginal secretion in two rape cases. We used primers flanking the hypervariable region of the D1S80 gene to amplify DNA extracted from fresh blood, blood stain, saliva stain, semen stain, mixed stain in vaginal swab, and from fetal tissues. The results revealed that 35 out of 85 alleged fathers in 85 paternity testing cases were excluded. In 30 of the 35 excluded cases, the alleged fathers were excluded by D1S80 locus analysis. The exclusion rate was 35.29%. In 2 of the excluded cases, the alleged fathers were excluded by D1S80 locus analysis only. In 50 nonexcluded paternity testing cases, the paternity index(PI) of D1S80 locus was 2. 0576-111.1111. It indicates that D1S80 locus analysis plays an important role in elevation the relative chance of paternity (RCP) value. In 41 of the 50 nonexcluded cases, RCP was higher that 99.75%. RCP reached 99.300%-99.649% in 9 of cases. In one rape and homicide case, the genotype of D1S80 locus of sperm on the vaginal swab was detected. It gave a clue to investigation. In the other rape case, the genotype of D1S80 of sperm on the vaginal swab was consistent with the blood stain from the suspect. So the suspect was not excluded. Since the D1S80 locus has a high discrimination power it is very useful for forensic individual identification and parentage testing. Some problems have been discussed in this paper.

Blood Stains↗

PubMed1997

[Evaluation of oral glucose tolerance test in the assessment of reserved function of liver for patients with hepatocellular carcinoma].

The aim of this study was to evaluate oral glucose tolerance test(OGTT)in the assessment of reserved function of liver for predicting the tolerability of patients to hepatectomy and hence provided a criteria for selecting the candidates for undergoing hepatectomy, since the majority of hepatocellular carcinoma (HCC) patients were associated with posthepatitis cirrhosis. The preoperative and postoperative OGTT and liver biopsy for pathological investigation were carried out in 62 cases of hepatecomized patients and 49 cases of unresected patients for comparison. The results revealed that the patients whose preoperative OGTT curve was of P type recovered uneventfully after hepatectomy, but those whose curve was of L type of tolerated poorly to hepatectomy and were liable to postoperative hepatic failure and complications. The severity of cirrbosis in those poor risk patients fell to C III or C IV histological degree. 29 patients with intermediate feature of OGTT curve between P type and L type, i.e. I type underwent regional vascular occlusion at hepatic hilus as hepatectomy, and infusion of Danshen extract solution before vascular occlusion to prevent hepatocytes from reperfusion injury. Of them, 20 recovered uneventfully, 8 suffered from complications such as ascites and/or juandice, and 1 died within 1 month after operation. The followup study showed that the survival time of patients with P type OGTT curve was longer than that of I type, and the latter was longer than that of L type. The pattern of OGTT curve could change from preoperative P type to postoperative L type, depending on the severity of vascular interruption of liver and the ischemic injury to hepatocytic mass in operation.

Adolescent↗