As monosaccharide polymers,polysaccharides are widely distributed in nature,they are found in microorganisms,plants and animal cells and tissues.Glycosylation is of importance to maintain the structural stability and biological activity of protein molecules in eukaryotic cells.Polysaccharides represent the most important antigens recognized by immune system.The innate immune system senses invading microbes via their pathogen-associated molecular patterns,using pattern-recognition receptors on the surface of innate immune cells,many of which are polysaccharides uniquely expressed in certain microorganisms.Polysaccharides can also be processed intracellularly and presented to ??-T cells by MHC molecules.Polysaccharides can activate B lymphocytes,with or without T cell help,and induce production of specific antibodies.Amongst the polysaccharide-specific antibodies in human sera,some are products of adaptive humoral responses against microbial infection and others autoantibodies to glycan epitopes of host cells.Patients with autoimmune disorders tend to have higher titers of antibodies against various glycans.Immune clearance of senescence cells depends on the recognition of altered glycan epitopes on cell surface.Modification of glycan epitopes on tumour cell surface is at least partially responsible for activating antitumor immunity.Specific recognition of polysaccharides by the immune system is of importance to immunological defence,autoimmunity,anti-tumour immunity and immunological homeostasis,it will be the new focus of immunology research in the near future.

Objective　To study the effects of air disinfect ion by three methods. Methods　Air was disinfected by ultraviol et rays, pentadialdchyde and ozone, efficiency of disinfection was eval uated b y three different disinfection methods using synchronous sampling after and b efo re disinfected. Results　The peak of the bacteria background by precussion method was 10 o'clock, by the ballistic method was 9 o'clock and by the petri dish method was 10 o'clock before disinfected. Three disinfect ion methods were significantly different, efficiency of disi nfection of pentadialdchyde was the highest when it was evaluated by the precuss io n method, and recovery of bacteria was 43.4%～55.8% after disinfected 3 h our s; effect of pentadialdchyde was better than that of the ballistic method, and r ecovery of bacte ria was 21.8%～35.7% after disinfected 3 hours; effect of ultra violet ra ys was better than that of the petri dish method, and recovery of bacteria was 4 2.1%～60.6% after disinfected 3 hours. But their differences were not significan t. In t he course of experiment, temperature and relative humidity have a negative impac t on the ultraviolet ray's efficiency and almost have no impact on others. Conclusions　Disinfection method of the ultraviolet rays could be rep laced by disinfection method of pentadialdchyde and ozone.

Objective To evaluate the protective effect of estrogen on survival of retinal ganglion cells (RGCs) after transient retinal ischemia-reperfusion (RIR) in rats. Methods RIR was induced in 60 ovariectomized adult rats (OVX) by increasing intraocular pressure via an intracameral catheter. All of the rats were divided into two groups randomly: in experimental group, the rats underwent a subcutaneous injection with 17?-estrodiol(100 ?g/kg) 2 hours before retinal ischemia; and in the control group, saline water was injected correspondingly. The number of RGCs and the thickness of the inner retinal layers were mesured by HE staining method before and 12, 24, 48, and 72 hours after reperfusion. TdT-mediated biotin-dUTP nick end labelling (TUNEL) staining technique was used to examine the apoptosis of RGCs. Results Twenty-four and 48 hours after reperfusion, the number of apoptotic cells in experimental group was obvious lower than that in the control group( P

Half-synthetic oil ester (of fruit of a cubeb litsea tree) Suppositories. The speed of medicine release was 85% within 20min in S-40 Suppositories and nearly 100% within 30 min. Conclusion: S-40 can be used as the ground substance for the antipyretic Suppositories for children.

The main progress in international critical care medicine in 2020 are: the reflections on the mandatory of implementation of the 1-hour cluster treatment strategy for sepsis are still continuing; the "metabolic resuscitation" therapy, represented by large dose of vitamin C, failed to yield positive results; the global epidemic of coronavirus disease 2019 (COVID-19) continues to spread, with evidences indicating Dexamethasone, Remdesivir or interferon β-1b (IFNβ-1b), Lopinavir/Ritonavir and ribavirin as promising therapy; conservative oxygen therapy did not exert positive effects neither for mechanical ventilated patients nor for acute respiratory distress syndrome (ARDS) patient; the concept of lung- and diaphragm-protective mechanical ventilation illuminates a new opportunity to potentially improve clinical outcomes for critically ill patients; there was no positive evidence for stress ulcer prophylaxis and timing of endoscopy for severe acute upper gastrointestinal bleeding; early initiation of renal-replacement therapy (RRT) for critically ill patients with acute kidney injury (AKI) has not shown positive effect. At last, artificial intelligence (AI) has shown good potential in identifying ARDS phenotypes and early predicting sepsis.

Objective:To investigate the relationship between reactive hyperplasia of the draining lymph nodes and oral cancer micrometastasis.Methods:The specimens was taken from 12 patients suffered from oral squamous cell carcinoma,who accepted inpatient care in West China College of Stomatology,Sichuan University.There were totally 233 lymph nodes,and all the specimens were divided into normal,reactive hyperplasia and metastasis groups by pathological diagnosis.Immunohistochemistry method was used to inspect micrometastasis in the two prior groups,and the data were analyzed with SPSS 10.0.Results:25 lymph nodes were detected metastasis,79 were reactive hyperplasia,and 129 were normal.Normal mucosa,squamous cell carcinoma and metastatic lymph nodes were positive to keratin,and there were 29 and 12 specimens with micrometastasis in reactive hyperplasia and normal lymph nodes separately.Conclusion:Micrometastasis occured on the reactive hyperplasia lymph node in the oral cancer draining area is easier than that on the normal one.

Objective: To study the role of simian virus 40 large T antigen(SV40LTag) and telomeras in the proliferation of endothelial cells in hemangioma. Methods: The expression of SV40LTag was examined in 100 cases of hemangioma with immunohistochemistry, telomerase activity and telomeric length were measured by RT-PCR based telomeric repeat amplification protocol(TRAP) assay, telomeric restriction fragment (TRF) analysis and chemiluminescence in situ hybridization in 50 cases of hemangioma and 10 of squamous cell carcinoma. A sample of embryonic kidney endothelia was used as the contrdol. Results: SV40LTag expression was observed in 45 out off the 100 cases of hemangioma. Telomerase expression was found in 27 out off the 50 cases of hemangioma and all the 10 of squamous cell carcinoma. The telomeric length in hemangioma varied from 6.8 to 13.2 kb, 10.5-13.5 kb in squamous cell carcinoma and 12.4 kb in embryonic kidney endothelia. Conclusion: Transformation of endothelia by simian virus 40 may contribute to the occurring of hemangioma, telomerase may play a role in the proliferation of the endothelial cells in hemangioma.

BACKGROUND: A stable and exact animal model is the necessary tool and basis for studying hemorrhagic cerebrovascular diseases.OBJECTIVE: To establish and evaluate the intracerebral capsular hemorrhage models in rats.DESIGN: A randomized and controlled animal experiment.SETTING: Second Hospital Affiliated to Xuzhou Medical College; First Hospital Affiliated to Nanjing Medical University.MATERIALS: This experiment was carried out in the animal experimental center of Nanjing Medical University during May to November 2002.Totally 35 SD rats were randomized into two groups: experimental group (n=30) and sham-operation group (n=5).METHODS: ① Autoblood was injected into the intracerebral capsule of rats to create intracerebral capsule hemorrhage models with stereotaxy in the experiment group. ②Scoring was conducted according to 5-point neurological scoring criteria from ZeaLonga, somatic sensation and motor function of rats were observed. ③Somatosensory evoked potential(SEP) of rats was detected pre- and post-operation under anesthetic state. ④ After determination of SEP, the rats were sacrificed under anesthetic state. Brains were taken out to made slices, then sections were stained with haematoxylin and eosin. Changes in haematoma and histomorphology were observed at the largest focus under optical microscope.MAIN OUTCOME MEASURES: ①Nerve function scoring; ②Latent period of various waves of SEP; ③ Observation of brain tissue morphology.RESULTS: Totally 35 rats entered the stage of result analysis. ①Appearance of obvious paralysis of the rats suggested the modeling was successful. The successful rate of this experiment was 93.3%(28/30). Significant difference existed in neurological scoring between experimental group [(2.74±0.46)points] and sham-operation group (0 point)(P＜0.05). ②SEP showed that the latent periods of various waves of experimental group after operation were significantly delayed than those before operation and those of sham-operation group [P1: (15.72±0.78) ms, (10.69±0.52) ms, (10.73±0.48) ms;Nl: (17.95±1.27) ms,(13.21±1.31) ms, (13.34±1.27) ms;N2:(21.16±1.62) ms, (15.42±1.46) ms,(15.58±1.44) ms;N3:(24.86±1.58) ms, (18.72±1.76) ms, (18.99±1.67) ms,P＜0.05]. ③In the shamoperation group, a few red blood cells were scattered in the peripheral area of needle channel were found, but hemorrhagic focus was not; In the experimental group, irregular or oval blood clots presented in the left internal capsule area. In about a low-fold visual field, brain tissue in the surrounding of hemorrhagic focus was loosened and swelled, and pathological changes were obviously severer than those in the sham-operation group.CONCLUSION: Intracerebral capsular hemorrhage induced by injection of autoblood with stereotaxy is more close to clinical situation, and it is easy to operate and has good reproducibility.

Objective To compare the effect of different ways of water supply and whether or not drain water from waterlines for overnight on bacterial counts in dental unit waterlines(DUWLs).Methods In the first phase,6 sets of DUWLs were randomly divided into 2 groups (external storage tank water supply group and municipal water sup-ply group);in the second phase,6 sets of DUWLs were all changed to use external storage tank and randomly di-vided into 2 groups (draining water for overnight group and without draining water for overnight group),bacterial count before and within one week of disinfection between two groups at two phases were compared respectively. Results In the first phase,handpiece water of DUWLs was most seriously contaminated by bacteria,the average colony count was 4117 CFU/mL,qualified rate was 15.38%.Before disinfection,no significant difference in bacte-rial count were found among each groups (all P>0.05),bacterial count of DUWLs of all groups severely exceeded the standard(all >3000 CFU/mL).Comparison of bacterial count in DUWLs from different water supply routes after disinfection was not significantly different on day 1(P>0.05),but were significantly different at day 2-7(all P<0.05).On the second day after disinfection,municipal water supply group began to exceed bacteria standard;on the third day after disinfection,external storage tank group began to exceed bacteria standard.Bacterial count in DUWLs after disinfection between draining water for overnight group and without draining water for overnight group was no significantly different on day 1(P>0.05),but were significantly different on day 2-7(all P<0.05). On the fourth day of disinfection,bacterial count of without draining water for overnight group exceeded standard.On day 7 of disinfection,bacterial count in draining water for overnight group exceeded>100 CFU/mL.Conclusion Use of external storage tank,daily change of sterile distilled water,and daily emptying water for overnight can effectively reduce bacterial count in DUWLs.

Objective: To analyze the effects of treatment of squamous cell carcinoma of tongue with N 0. Methods: 145 cases of squamous cell carcinoma of tongue with N 0 were retrospectively reviewed.22 cases underwent resection of primary tumor without elective neck dissection (END) (control group).123 cases underwent resection of primary tumor with END (END group).Follow-up was carried out for more than 3 years or till the death of patients.Results:Lymph node metastases was indentified in 33 patients in END group after operation and in 4 in control gruop during follow-up.The total occult lymph node metastases was found in 25.52% of the patients.4 (18.18%) died from neck or lung metastasis in control group and 7 (5.69%) in END group (P