Quorum sensing is defined as the cell density-dependent regulation of gene expression, and the involved system is the quorum sensing system, in which N-acyl homoserine lactone is known as the signal molecules of most gram-negative organisms. It can regulate diverse physiological functions. This paper reviewed the quorum sensing systems and the recent advances which play a major role in the formation of the symbiosis between the rhizobia and their host plants.

strains of fast-growing rhizobia isolated from Chinas western (mainly from Qinghai province),and 4 representative strains were compared by performing numerical taxonomy. 132 phenotypic characteristics were analyzed. The results of numerical taxonomy constructed a dendrogram. It shows that all the strains examined clustered into five phena at a similarity level of 79%. 16S rDNA PCR-RFLP were applied to 57 rhizobial strains (among the 61 strains) and 10 reference strains. The 16S rDNA-RFLP analysis described 20 different genotypic characteristics and form one dendrogram. For some large groups, the results of 16S rDNA-RFLP were agreement with that of numerical analysis of phenotypic characteristics.

The Baculoviridae are a large family of enveloped DNA viruses exclusively pathogenic to arthropods. Baculoviruses have been extensively used in insect cell-based recombinant protein expression system and as biological pesticides. They have been deomostrated to be safe to mammals, birds and fish. Recently, baculoviruses has been shown to transduce different mammalian cells in spite of the fact that they cannot replicate in mammalian cells (11, 73, 76). This has resulted in the development of baculoviruses as mammalian expression systems and even as vestors for gene therapy.

Child, Preschool ; Histoplasmosis ; complications ; pathology ; Humans ; Lymph Nodes ; pathology ; Male ; Mycobacterium Infections ; etiology

Eustachian Tube ; abnormalities ; surgery ; Humans ; Laser Therapy ; Male ; Middle Aged ; Prosthesis Implantation ; Stents ; Tympanoplasty

Adolescent ; Child ; Child, Preschool ; CpG Islands ; Cyclin-Dependent Kinase Inhibitor p15 ; genetics ; DNA Methylation ; Female ; Humans ; Leukemia, Myeloid, Acute ; genetics ; Male ; Promoter Regions, Genetic

Objective To investigate the correlation between the degree of pathogenetic condition and cogni-tive impairment in young OSAHS patients. Methods Sixty-three patients (18～44 years old) were divided into 3 groups according to the assessment criteria regarding the degrees of pathogenetic conditions of hypoxemia and its persistence time: mild group(the lowest SaO2 ≥ 85 %, n = 20 ), moderate group (the lowest SaO2 : 65 ～ 84 %, n =24), and severe group (the lowest SAO2<65%, n= 19). Twenty-five healthy young adults were selected as the control group. All the subjects were tested with event-related potential, namely P300, the polysomnogram and the mini-mental state examination scale(MMSE). Results P300 latency in patients of three OSAHS groups was sig-nificantly prolonged as 326.1±12.7, 346.9±19.1, and 34.9±18.3 ms, as compared with those of control group: 311.9±18.3 ms (P< 0.05, respectively). In severe group, P300 latency was markedly increased compared with mild and moderate groups(P<0.01, P<0.05, respectively). No obvious differences were observed between mild and moderate groups(P=0. 095). The difference of hypoxemia lasting time could influence the P300 latency, such as when the hypoxemia lasting time was 4～60 seconds, the latency was 338. 12±13.7 ms, and when the hypoxemia lasting time increased to 60 ～ 140 s, the latency was prolonged to 354.74±16.7 ms(P = 0. 031 ). There was no difference among all groups in the P300 amplitudes. The MMSE scores for all patients were within normal limits andthere were differences between serve and control group(RA -RB=9. 91, P= 0. 003). Conclusion Among patients with OS-AHS, the impairment of cognitive function is con'anon. The degrees of pathogenetic conditions of hypoxemia and its lasting time may be used to evaluate the impairment degree of cognitive function in patients with OSAHS.

Objective:To study the role of RapIDYeast Plus (RYP) system in identifying common clinical yeasts.Methods: The target strains were cultured and passaged twice on Sabouraud dextrose agar,and were fed to RYP system after 24-48 h incubation at 30℃.Results: One hundred and thirty-nine of the 150 target strains were identified to the level of species correctly,and 8 undetermined strains were confirmed by additional tests.It was found that 3 strains had been incorrectly identified by RYP system.The accuracy of RYP system was calculated as 92% without additional tests and 98% with additional tests.Conclusion: RYP system is suitable for routine tests in clinical microbiological laboratory;it can accurately identify more than 40 kinds of yeasts and yeast-like bacteria in clinical practice.

Objective To observe the effects of repeated +10 Gz stress on cerebral lipid peroxidation,liver and renal function in rats and the prophylactic effects of antioxidant tea polyphenols(TP).Method Twenty-four male Wistar rats were randomly divided into three groups(n=8 each):group A(control),group B(+10 Gz),and group C(TP).Group B and C were exposed to repeated +10 Gz stress(each for 30s,onset rate about 0.5 G/s,3 times/d with +1 Gz 1 min intervals,3 d/wk,4 weeks in total),but group A was only submitted to +1 Gz.TP(200 mg/kg) was given orally in group C about 1 h prior to the +Gz experiment,while distilled water was given in group A and B.Lipid peroxidation in the brain,liver and renal functions and serum lipids were determined.Results As compared with the control,lipid peroxidation in rat cerebral homogenate,mitochondria and cytoplasm was significantly increased( P<0.05),and serum creatinine concentration was markedly elevated after repeated +10 Gz stress(P<0.01).But,TP had significant inhibitory effect on +10 Gz stress induced peroxidative injury in rat brain and reduced the serum creatinine level.There were no differences of serum triglyceride and total cholesterol concentrations and glutamic-pyruvic transaminase activity among the three groups.Conclusion These results indicated that repeated high +Gz stress could bring about peroxidative injury in brain and harmful effect on renal function,and natural antioxidant TP had signficant protective effects.

We aimed to make comprehensive cancer care guidelines of China according to American guidelines of National Comprehensive Cancer Network,Ametican Society of Clinical Oncology and Oncology Nursing Society,and to guide clinical nurses to study and draw lessons from foreign latest guidelines,and combined with the actual situation in our country.The results of study and application were advantageous to the nursing profession,the security and interests of the patients.We should develop comprehensive cancer care guidelines of our country,eventually make nursing practice guide system of China constantly improve and perfect.