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Biomedical subjects

G Li

Publications and source records attributed to G Li.

At least 739 records · Page 41Linked to original sources

[A study on risk factors of neural tube defects].

One hundred and twenty-three cases with neural tube defects collected during 1991 to 1993 from 12 hospitals with birth defect surveillance in Hebei Province, and their pair-matched controls were analyzed with single and multiple conditional logistic regression to study the effects of food and drinking water on occurrence of neural tube defects. Results showed factors contributing to neural tube defects were maternal previous history of birth defects, much consumption of dried and pickled vegetables during pregnancy, too much nitrate content in drinking water (containing more than 10 mg nitrogen per liter of water), less consumption of meat, eggs, and beans in their diet.

China↗

[A study of P53 protein expression in fibrous neoplasms].

An immunohistochemical method utilizing microwave oven treated avidin-biotin complex (ABC) technique was used in this study to detect P53 protein expression in 87 parafin-embedded fibrous neoplasm tissues. The results showed that the total positive staining rate was 20.7%. The positive staining rate in fibroma (FA), dermatofibrosarcoma protuberans (DFSP) fibrosarcoma (FS) and malignant fibrous histiocytoma (MFH) were 0%, 4.0%, 37.5% and 62.5% respectively. The positive staining rate of P53 protein was increased with the increase in malignancy of the neoplasma. The expression of P53 protein was not correlated with the subtypes of DFSP and MFH, but correlated with cell differentiation. Therefore, detection of P53 protein expression may have significant value in the evaluation of malignancy, metastatic potential and the prognosis of fibrous neoplasma.

Dermatofibrosarcoma↗

Crashes of instructional flights.

BACKGROUND: A pilot's basic flight training influences his or her entire flying career. Instructional flights are involved in more than 300 crashes annually and in 36% of all midair collisions. Research was undertaken to identify the circumstances of crashes of instructional flights and to describe related factors. METHODS: We analyzed NTSB data types and 2-page descriptive briefs for 638 crashes that occurred during 1989 and 1991 and that involved a student pilot or a flight for instructional purposes. RESULTS: Loss of control on landing characterized 36% of all crashes, and crosswinds contributed to 28%. Stalls occurred in 15% of the series and 46% of all fatal crashes. Trainees on solo comprised 56% of the series; 193 of the 360 students who crashed on solo did so due to loss of control on landing or takeoff. Touch-and-go landings accounted for 22% of all crashes on solo. Among the 84 crashes on cross-country solos, 26 (31%) were due to running out of fuel. Instructors were present in 50% of crashes from stalls and 32% of crashes from fuel starvation. Simulated emergencies ended in 49 crashes. The NTSB identified instructor factors as contributory to one-third of cases. CONCLUSIONS: Greater emphasis during flight training needs to be placed on avoiding stalls and midair collisions, managing crosswinds, and understanding the dynamics of takeoffs and landings prior to solo touch-and-go practice. Instructors contribute to crashes both directly during dual instruction and indirectly through failure to successfully monitor their students and convey the elements necessary for safe and proficient flight.

Accidents, Aviation↗

Experimental study on spontaneous DNA synthesis of tonsillar lymphocytes in chronic recurrent tonsillitis and focal tonsillitis.

The immune function of tonsils and the immunological mechanisms of focal tonsillitis are still controversial. We do have some knowledge about the structure of tonsillar cells, but their functional status is still not clear. In 40 cases of chronic recurrent tonsillitis and 20 cases of focal tonsillitis with glomerular nephritis, cell culture of tonsillar lymphocytes was removed in vitro and 3H-tymidin incorporation applied to investigate the spontaneous DNA synthesis of tonsillar lymphocytes. The results demonstrated that: i) In chronic tonsillitis, spontaneous DNA synthesis of tonsillar lymphocytes in children is significantly stronger than that in adults (19,946 +/- 5,612 vs 9,216 +/- 5,702 cpm) (p <0.01). ii) Spontaneous DNA synthesis of tonsillar lymphocytes in focal tonsillitis is significantly stronger than that in the chronic recurrent tonsillitis in patients of the same age (25,307 +/- 12,231 cpm vs 12,455 +/- 7,914 cpm) (p <0.01). This indicates that the tonsillar lymphocytes are active in focal tonsillitis, can produce large amounts of memory B-cell clones, which reach other parts of the body through the blood and cause autoimmune reaction which can be blocked by tonsillectomy, thus curing the systemic disease.

Adolescent↗

[Computed tomographic features of malignant fibrous histiocytoma].

CT findings in 45 cases of malignant fibrous histiocytoma (MFH) were reviewed. There were 27 primary and 22 (23 episodes) cases of recurrent tumor, 4 (5 episodes) cases of recurrent tumor were initially treated in our hospital. Tumors located in craniofacial area in 16 cases, abdomen or retroperitoneum in 17, soft tissues of extremities or trunk in 12. There were 26 male and 19 female patients, with 19-82 years of age (medium, 46 years of age). The most common clinical symptom was a local mass (64.4%). On CT scan, 84% (42/50) of lesions with tumor mass > 5 cm, mostly with irregular contour, medium to markedly hyper-attenuated enhancement were revealed in 78.8% of cases and 60.6% of cases with hypo-attenuated necrotic area inside. Most of the tumors invaded adjacent organs or structures which were revealed in 75.8% of cases, such as infratemporal fossa, pterygopalatine fossa, extradural space in the craniofacial lesions; liver, psoas muscle, abdominal wall in abdominal and retroperitoneal lesions. Expansible change could be shown when paranasal sinus was invaded (8/9). The CT findings of recurrent lesions were similar to the primary ones. Enhanced CT scan may provide useful information in demonstrating the nature and extent of invasion of the tumor. Closely integrating CT and pathologic findings is important for the differential diagnosis of malignant tumors of soft tissue.

Adult↗

Prevalence and incidence of NIDDM in Daqing City.

OBJECTIVE: To investigate the prevalence and incidence of non-insulin dependent diabetes (NIDDM) in China by WHO criteria. METHODS: In the prevalence survey of NIDDM all 110660 participants (55391 men, 53269 women) were inhabitants of Daqing City, the largest oil center in northeast China, accounting for 87.3% of the 25 to 74 aged population in this city. They were screened by measuring two-hour plasma glucose concentrations (PG2 h) after a breakfast containing at least 80 g of carbohydrate, then a standard oral glucose tolerance test (OGTT, 75 g glucose load) was performed in 4209 subjects with PG2 h more than 6.67 mmol/L in this screen. NIDDM and impaired glucose tolerance (IGT) were diagnosed using WHO criteria. Incidence survey was made in 36471 non-diabetics identified in the prevalence survey. Two-hour urine-glucose after breakfast was determined during first screen. The urine-glucose trace or positive subjects were then followed by OGTT. Glucose was measured by glucose oxidation method. RESULTS AND CONCLUSIONS: In prevalence survey, 630 newly diagnosed NIDDM (296 males, 334 females) and 596 IGT (318 males, 278 females) were found in 110660 (male:female = 55391/53269) studied subjects in addition to 190 previously diagnosed NIDDM. Thus the total prevalence of NIDDM was 7.7/1000, and IGT was 5.5/1000. Standardized to the Chinese population in 1982, the prevalences are 12.6/1000 (95% CI = 12.0/1000-13.3/1000) and 7.7/1000 (95% CI = 7.16/1000-8.19/1000) respectively. In the incidence survey, 191 NIDDM (103 males, 88 females) were diagnosed in the 36471 (male:female = 18801/17670) non-diabetics from 1986 to 1990, thus the annual incidence of NIDDM was 131/100000 (137 males, 125 females). Standardized incidence is 131/100000 (95% CI = 94/100000-168/ 100000). It is estimated that there would be more than 700 thousand new diabetics per year in 24-74 years old Chinese if Chinese population were 1.3 billion in the early 21st century.

Adult↗

A clinical study on severe hydroa vacciniforme.

OBJECTIVE: To describe a severe type of hydroa vacciniforme (HV) in order to provide basis for treatment and prevention of this disease. METHODS: Nine cases of HV were collected in our outpatient department, and clinical and laboratory examinations were performed. RESULTS: All the cases had erythemas, papules, bullae, erosions or ulcers on exposed sites, with recurrences, gradually resulting in deformation. Five patients suffered from hand deformation manifesting rigidity, flexor tetanus, or malposition of the first, second and third interphalangeal joints of hands. Two of the above mentioned patients manifested partial bone absorption of fingers. Five patients showed partial defect of auricle. Two patients showed saddle nose, and partial absorption of nasal cartilage. One patient displayed cicatricial contracture of lower lip, with incisor extrusion. Four patients showed opacity of cornea. Through laboratory examinations, porphyrinopathies were excluded. Phototests showed increased sensitivity to ultraviolet-A radiation (UVA). CONCLUSIONS: Based on the clinical features and laboratory examinations, these patients were diagnosed as having severe HV. It is believed that this condition belongs to a disease spectrum induced by ultraviolet light. Our analysis suggests that for children with severe type of HV, preventive measures and therapeutic agents should be taken as soon as possible in order to avoid deterioration of the disease and malformations.

Adolescent↗

Searching eye movement, smooth pursuit eye movement and schizophrenia.

OBJECTIVE: To detect whether the smooth pursuit eye movement (SPEM) and searching eye movement (SEM) could be considered as a biological marker of schizophrenia, and used as a tool in helping diagnosis of schizophrenia. METHODS: 88 schizophrenics, 77 patients with mood disorders, 32 with "neurosis", and 74 normal healthy controls were examined for SPEM and SEM individually. The authors verified the results in all the first-visit 150 outpatients in March 1993 by comparing the examination results with the clinical diagnoses after a 6-month follow-up. RESULTS: Significant differences were found in the number of eye fixation (NEF) and total eye scanning length (TESL) of SEM between schizophrenics and normal controls or patients with other disorders. Less NEF and shorter TESL could be helpful in differential diagnosis, and the agreement rate, Kappa coefficient was 0.62. No significant differences were found in SPEM in this investigation between non-medicated schizophrenics and normal controls. CONCLUSION: Searching eye movement (SEM) might be considered as a biological marker of schizophrenia and might be used as a supplementary tool in its diagnosis.

Adult↗

[Ultrastructural changes in various cataractous lenses in rats].

OBJECTIVE: To study the ultrastructural changes of lenses aged 50 days from normal rats and rats with three kinds of cataract. METHOD: Transmission electron microscope (TEM) was used to investigate the ultrastructural changes of normal lens, selenium, galactosemic and congenital cataracts in the rat. RESULTS: In the normal group, the structure of cell membrane in cortex is not changed obviously, but in the lens nucleus there are slight cellular degeneration, low cytoplasmic density and the destruction of intercellular junctional complexes. In the selenium cataratous lens, in the lens cortex and nucleus the cellular junctional complexes are damaged severely, the cystic degeneration of mitochondria in the cytoplasm is obvious, the cytoplasmic density becomes lower and slight liquefaction can be observed in some parts of cytoplasm. In the galactosemic cataractous lens, in the cortex obvious liquefaction, vesicles and globular structures can be found within the cytoplasm, intercellular spaces are enlarged and liquified markedly, and in the lens nuclear area the cytoplasm appears as fine sands. In congenital cataractous lens, the cellular structure in cortex is essentially normal, but there are marked destruction of junctional complexes, obvious cystic degeneration of mitochondria and cytoplasmic aggregation with uneven distribution in the lens nuclear area. CONCLUSION: The ultrastructural changes in different kinds of cataractous lenses depend on the extent and location of opacification in lenses.

Animals↗

[Effects of processing on specific toxicity and pharmacodynamics of radix Kansui, radix Achyranthis bidentatae and semen Armeniacae amarum].

The comparative toxicological researches on crude and processed drugs show that the activating action of Radix Kansui, Radix Achyranthis Bidentatae and Semen Armeniacae Amarum on EBV-EA can be decreased by processing. Processing can also decrease stimulating activity on mouse skin, inhibit tumor-promoting activity in two stage skin tumor promoting test and lapactic effect by Radix Kansui. Meanwhile the pharmacological effects of these drugs can be retained or increased by processing.

Animals↗

Spike waves and synaptic ultrastructure in human epileptic brains.

OBJECTIVE: To find morphological changes of synapses related to the spike discharge by observation on ultrastructures of the EEG spike foci of cerebral cortexes. MATERIAL AND METHODS: The cerebral cortexes were obtained surgically from the EEG spike (recorded by flaky silver electrodes on the surface of cortexes) foci and nonspike areas within the limits of the brain tissue that would be removed in 20 cases of human epilepsy, and were processed for transmission electron microscopic (TEM) observation. RESULTS: In the spike foci, presynaptic terminals of axospinal asymmetric synapses were obviously swollen but postsynaptic spines were relatively unaffected. In these synapses, the synaptic vesicles remarkably decreased in number and accumulated predominantly at the presynaptic membranes or aggregated. Similar changes were observed in the presynaptic terminals of the axospinal asymmetric synapses in the nonspike areas but were of milder degree than in the spike foci. CONCLUSION: Axospinal asymmetric synapses may release a large quantity of excitatory neurotransmitters, which may result in epileptic abnormal electric activities during seizure.

Adolescent↗

Seroepidemiological studies on Silk Road ethnic groups.

To clarify the origin of the Japanese, the Jomom and/or Yayol, we screened for HTLV-1 and -II antibodies among inhabitants of the Silk Road, the Han, Uygur and Kazaks. We also screened for HIV, HBV, and HCV. The HTLV-I, -II, HIV, and HCV antibody tests were uniformly negative in all the studied groups. In contrast, a significantly higher incidence of HBs antigen was observed in all the groups tested (Northern Han: 11.9%, Uygur: 6.0%, Kazak: 9.1%). These results indicate that these ethnic groups are not the origin of the indigenous Japanese (the Jomon), and that HBV is prevalent in the various groups along the Silk Road.

Antigens, Viral↗

[Magnetic resonance imaging of laryngeal cancer].

MRI data of twenty-four cases of laryngeal cancer were analysed and compared with the findings of postsurgical pathology. The results revealed that MRI could clearly demonstrate the three dimensional representations of tumor pathology, and correctly depict invasion of paraglottic space (PGS), and preepiglottic space (PES), and precisely display involvement of laryngeal cartilage by cancer. It was considered that MRI was of great importance in determining appropriate therapy for laryngeal cancer.

Adult↗

[Detection of micrometastases in axillary lymph nodes of node-negative breast cancer patients and its clinical significance].

Monoclonal antibodies against cytokeratin (AE1/AE3) were applied as a prob, using APAAP immunohistochemistry technique to detect 635 lymph nodes from 45 breast cancer patients with negative lymph nodes. Micrometastases were identified in 14 lymph nodes of 9 cases (20%). A significant difference was found between cytokeratin staining positive group and cytokeratin staining negative group in disease-free and over-all Kaplan-Meier survival curves. The detection of micrometastases had more clinical value for T1 and T2 patients. One of 2 T1 cytokeratin positive cases relapsed while only 1 of 19 T1 negative cases relapsed within 5 years, three of 5 T2 cytokeratin positive cases relapsed while 1 of 17 negative cases did. The presence of micrometastases had the same value in predicting local recurrence and distant metastases.

Adenocarcinoma↗

[Double cancers: a clinical analysis of 156 cases].

In order to study the causes of multiple primary carcinomas (MPC), and to give proper treatment, 156 patients with double cancers were analyzed retrospectively. The patients were admitted to the hospital from 1982 to 1987, accounting 0.47% of all hospitalized patients with malignant tumors in the same period. Out of them 86 patients were male, 70 patients were female. The age ranged from 17 to 80 old-year, the median 50 old-year. In 34 cases, the two cancers were synchronous in occurrence while in 122 cases were metachronous. The nasopharynx, lungs, large bowel and mammary gland were the most common sites of the MPC. The principle of treatment of the MPC was the same as that for ordinary primary carcinoma. The total 5-year survival rate was 34.6%.

Adolescent↗

[A study of treatment modalities for nonresectable primary liver cancer].

This paper reports the results of multimodality treatment in 200 patients with nonresectable primary liver carcinoma (PLC) from April 1964 to July 1993. PLC was verified histologically in all cases. They were divided into two groups according to the methods of treatment. In group 1, 115 cases received anticancer agents by hepatic artery infusion (HAI). The 1- and 2-year survival rate was 10.4% and 1.7%, respectively and only one patient survived 65 months. In group 2, 85 cases received multimodality treatments by various combinations of hepatic artery chemoembolization (HACE), hepatic artery ligation (HAL), microwave coagulation (MIC) of tumor and ethanol injection into tumor (EIT). The 1-, 2-, 3- and 5-year survival rate was 34.1%, 21.2%, 12.0% and 6.7%, respectively. Five patients had been alive for 41 to 63 months and second-stage hepatic resection performed in another 6 patients. The results suggest that multimodality treatment is an effective approach to improve the long-term survival of patients with nonresectable PLC.

Adult↗