Objective To investigate the formaldehyde emission rate of wood-based materials sold in Hangzhou and to ana-lyze its emission characteristics.Methods Four kinds of wood-based materials were selected and the formaldehyde emission rates were determined by applying the balancing concentration method of small environmental test chamber and the emission rates of different kinds of the materials were compared.Results A-level wood-based materials were of40%,B-level50%and C-level10%of the whole.The formaldehyde emission rates of these different kind of wood-based materials were significantly different (0.01

Objective To assess the value of 18F-FDG PET/CT in clinical classification,monitoring of chemotherapeutic response and surveillance of histopathological transformation of Castleman's disease (CD).Methods Fourteen pathologically diagnosed CD patients (7 males,7 females; mean age:(45.64±14.30) years) were retrospectively reviewed.18F-FDG PET/CT was performed before chemotherapy in all patients and 4 of 14 patients were reexamined after the treatment.The study parameters included histopathological results,sites,number and highest SUVmax of the lesions.Mann-Whitney and Kruskal-Wallis tests were used for data analysis.Results Of all the 12 patients without histopathological transformation,one or more enlarged and metabolically active lymph nodes were found in each patient (SUVmax =3.94± 1.44,range:1.9-6.8),including 2 unicentric CD (UCD) and 10 multicentric CD (MCD).There was no statistically significant difference of SUVmam between UCD and MCD (4.55±3.18 vs 3.82±1.14; Z=0.22,P＞0.05).There was also no significant difference of SUVmax among different pathological types (hyaline-vascular CD (4/12):3.56±0.96,plasma cell CD (6/12):4.73±1.41,mixed CD (2/12):2.30±0.57; x2 =4.74,P＞0.05).For the 4 patients with follow-up PET/CT after chemotherapy,the lesion activity was normalized in 3 patients and clearly reduced in 1 patient.The SUVmax of 2 patients with histopathological transformation (10.85±2.05) was significantly higher than that without transformation (3.94± 1.44; Z=-2.19,P＜0.05).Conclusion 18F-FDG PET/CT may play an important role in clinical classification,monitoring of chemotherapeutic response and surveillance of histopathological transformation of CD.

BACKGROUND: Patients with Alzheimer disease (AD) usually have visuospatial dysfunction at an early stage and most patients with AD were evolved from mild cognitive impairment (MCI).OBJECTIVE: To detect whether a patient with MCI has a visuospatial dysfunction similar to AD. To compare the cerebral activation with ferromagnetic resonance between the healthy people and the patients with mild cognitive disorder.DESIGN: A case controlled observationSETTING: The Department of Neurology of the First Hospital of Peking University.PARTICIPANTS: Nine inpatients with mild cognitive disorder hospitalized at the Department of Neurology of the First Hospital of Peking University from April 2000 to March 2003 were involved and other 9 healthy people matching in age, gender and the educational level were also involved.METHODS: The subjects had the task of discriminating the different finger positions on the clockface. They could see the mission clearly showed on the cloth through refractor, and they were supposed to give the corresponding reaction to different cognitive tasks with left and right hands pressing the keys according to visual sign generated by the computer.Block design was adopted in the cognitive task. Stimulus block and baseline block appeared in turn. Baseline block displayed "+" mapped in the center of the image and was kept for 21s. Stimulus block displayed 10 pictures successively. The finger position of the two clockfaces among three clockfaces was the same in one picture. The absolute value of the rotated angles of the different clockfaces in each image on the same stimulus block was the same. The angles formed by six stimulus block fingers arranged randomly were 300, 450, 1800. The two clockfaces had the same finger positions, and the subjects were requested to discriminate the finger position of these two clockfaces. It was carried out on a 1.5 T GEMRTWIN magnetic resonance scanning apparatus. Then t test was performed to work out the right reaction time and proper rate with Excel software between the patients with mild Alzheimer's disease and the healthy persons. Pretreatment and statistical analyses were performed with analysis of functional neuroimages software used internationally.MAIN OUTCOME MEASURES: Comparison of the reaction time and proper rate between the two groups.parison of the reaction time between the two groups: The reaction time for distinguishing the change of 300, 450, 1800 was longer than that in the control group, and there was significant difference in distinguishing the change of 300, 450, 1800 for the patients [(1 776.7±570.2), (1 646.3±432.7)ms;of the proper rate between the two groups: The proper rate for distinguishing the change of 300, 450, 1800 was significantly lower than that in the control group (62.8±21.4)%, (82.8±15.8)% ;(76.7±17.0)%, (95.0±8.7)%; (69.4vation: the activation density at the bilateral parietal lobe, bilateral temporooccipital borderline and bilateral lateral striate cortex in patients was weaker than that in the control group (P ＜ 0.05).CONCLUSION: Neural network activation related with visual space in patients with MCI was weaker than that in the healthy people indicating that visuospatial impairment exists in the patients with mild cognitive impairment.

ObjectiveTo explore the early diagnosis of Alzheimer's disease (AD),the arithmetic calculation ability in the patients with mild cognitive impairment (MCI) was detected under the functional magnetic resonance imaging (fMRI),combined with the neuropsychological test.Methods8 patients with MCI and 9 controls matched for the age, gender, level of education and handedness performed the subtraction of two digits presented visually while the MR machine was scanning. The raw data of the fMRI were processed with the software AFNI. The reaction time and correct ratio were analyzed with the statistical software Excel.ResultsCompared with the controls, the patients manifested longer reaction time and lower correct ratio. The patients' brain activation showed significant decrease in the inferior frontal lobe,temporal neocortex and inferior parietal area mainly in the left hemisphere. On the contrary, the activation intensity and extension in the right inferior frontal lobe were increased as compensation.ConclusionsThe patients with MCI have the deficit in calculation ability. The examination of the calculation by means of the cognitive neuropsychology and fMRI test can offer a powerful reference for the early diagnosis of AD.

Objective To investigate the underlying neural mechanism of left hemiparalexia and left hemialexia in reading Chinese characters. Methods A patient with reading disorders caused by brain infarctions at the left ventralis medialis occipitotemporal lobe and the splenium of the corpus callosum was studied. A series of neuropsychological tests, such as reading Chinese characters presented in the central foveal field or in the left and right half of the foveal field, were conducted with the patient, and neuroimaging techniques including high spatial resolution 3D-MRI and diffusion tensor tractography (DTT) were used to examine whether or not there were lesions of the neural pathway. Results The patient showed left hemiparalexia, which was characterized by making substitution or omission mistakes, mostly in the left parts of Chinese characters, and also left hemialexia(alexia for characters presented in left visual field). 3D-MRI demonstrated infarctions in the left ventral mesial occipitotemporal area and in the left side of the splenium of the corpus callosum. The left lateral mid-fusiform cortex, which has been identified as the visual word form area(VWFA), was almost intact. DTT indicated the major forceps fibers running through the splenium were all disconnected due to the infarction of the left splenium. Conclusion As a result of disruption of the splemium-major forceps pathway, visual character information in the left visual field which is initially projected to the right occipital cortex cannot be transferred from the right visual cortex to the left VWFA. This mechanism of left hemiparalexia and left hemialexia in reading Chinese characters is similar to that in reading English words.

To analyze the structural characteristics of the Rap2B gene from Clonorchis sinensis by bioinformatics and to clone and express this gene through genetic engineering methods in order to obtain the corresponding recombinant protein.The structural and functional characteristics of the Rap2B protein were analyzed by using the related bioinformatic softwares. Using the full-length cDNA plasmid clone (Noc009e03) as template , the coding region of Rap2B gene sequence was amplified with PCR and cloned into the prokaryotic expression vector pET-28a(+) and then expressed in E.coli BL21 through IPIG induction. The recombinant protein expressed was purified by Ni-IDA affinity chromatography and detected by SDS-PAGE and Western blotting. It was demonstrated that the size of this gene was 847 bp in length, encoding 141 amino acids and its theoretical molecular weight was 15851.1 daltons. As demonstrated by PCR, double enzyme digestion and DNA sequencing, the recombinant expression plasmid pET-28a(+)-Rap2B was successively constructed and the Rap2B-like gene was highly expressed in E.coli BL21. The recombinant protein was obtained through purification with His affinity chromatography and could react specifically with the serum of rats infected with C.sinensis. Through these investigations, the Rap2B protein may be predicted as a member of the Ras oncogene family protein and is potential in the carcinogenic process of C.sinensis.

phological changes in rat liver tissues. TLR4 and NF-κB expression in the liver tissues were measured by im-munohistochemistry . The results showed that compared with the normal group , the serum levels of transaminase ( ALT , AST ) and endotoxin of the model group were higher ( P < 0 . 01 ); and the degree of liver pathology injury was significantly increased; the TLR4 and NF-кB expression were increased (P < 0.01). Compared with the model group, the serum levels of transaminase (ALT, AST) and endotoxin of the experimental group were lower (P < 0.01), the degree of liver pathology injury was significantly lighter; the TLR4 and NF-кB expression were significantly lower (P < 0.01). It was concluded that the WYJDHY granules has a good role in the prevention and treatment of liver injury of rat model of hepatic failure IETM through the downregulation of liver expression of TLR4 and NF-кB in rat liver tissues , reducing serum levels of endotoxin , which may be one of the mecha-nisms on hepatic failure treatment .

Objective To evaluate the usefulness of delayed parenchymal transit time (PTT) on 99TcmDTPA diuretic renography as a predictor for functional improvement after Anderson-Hynes dismembered pyeloplasty in patients with ureteropelvic junction obstruction (UPJO).Methods Forty-seven patients (37males,10 females,age (29.7± 10.8) years) with unilateral U PJO were retrospectively analyzed.All patients underwent 99Tcm-DTPA diuretic renography before and after the surgery.Patient age,sex,UPJO location,surgical methods,relative renal function (RRF) of the diseased kidney (uptake ratio of UPJO kidney to both kidneys),and PTT were recorded.Delayed PTT was defined as having one of the following criteria: (1) photopenic pelvis between the second and seventh frame; (2) relatively stable tracer distribution within the kidney between the second to ninth frame with nearly unchanged kidney shape and size; (3) ever increasing activity in the parenchyma; (4) slower clearance from the parenchyma into the pelvis since the second frame compared with the contralateral healthy kidney.The relationship between the above-mentioned factors and RRF improvement (RRFpvst-surgery,-RRFpre-sugery) was analyzed.Paired t test,Kruskal-Wallis and Mann-Whitney rank sum tests and Pearson correlation analysis were used.Results The average RRF of pre-and post-surgery was (40.70± 13.30) ％ and (44.96 ± 12.60) ％,respectively (t =4.19,P ＜ 0.01).RRF improvement between the delayed group (n=16) and normal timely PTT group (n=27) was significantly different: ((11.69±6.52) ％ vs (0.48±2.98) ％,Z=-5.13,P＜0.01).The assessment of delayed or normal PTT could not be determined in 4 patients.No statistically significant differences of RRF improvement were found between pre-surgery RRF ＜ 40％ and RRF ≥ 40％ groups,between left and right UPJO groups,between open surgery and laparoscope groups,between male and female patients (Z =-1.93 to 1.25,all P＞0.05).There was no significant correlation between RRF improvement and patient age (r =0.01,P＞0.05).Conclusion Delayed PTT on 99Tcm-DTPA diuretic renography might be the predictor for functional improvement post surgery in UPJO patients.

Objective: To evaluate the diagnostic value of fluorine-18 fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/computed tomography ( PET/CT) in fever of unknown origin ( FUO) in a Chinese hospital .Methods:The records of 51 patients with FUO (32 men and 19 women;mean age 54 years with a range between 3 and 81 years) were analyzed retrospectively .All the patients were examined by 18 F-FDG PET/CT scan and the results were compared with the final diagnosis which was established by additional procedures including pathology , laboratory examination , and clinical follow-up for more than 3 months.The t test was used for statistical analysis .Results: A final diagnosis was established for 48 patients , including 32 patients with infectious diseases , 9 with malignancies , and 7 with non-infectious inflammatory diseases .By FDG PET scan alone , the rates of true positive , false positive , false negative, and true negative were 52.9%, 27.5%, 17.6%, and 2.0%, respectively.By FDG PET/CT scan, the rates of true positive, false positive, false negative, and true negative were 70.6%, 27.5%, 2.0%, and 0, respectively.18F-PET/CT had a sensitivity of 97.3%(36/37), specificity of 0 (0/14), and accuracy of 70.6%(36/51) in FUO, especially a high sensitivity and accuracy of 100%(9/9) in the diagnosis of malignant tumor .Moreover , the maximum standardized uptake value ( SUVmax ) in tumor was significant higher than that in infection (3.7 ±2.7 vs.7.7 ±3.5, P=0.001, t=3.6), which implied that SUVmax might be useful in differential diagnosis in FUO .Conclusion:FDG PET/CT is a valuable imaging tool for the identification and location of the potential lesion in FUO and is helpful for the etiological diagnosis , especially in the diagnosis of malignant lesions .

Objective To evaluate and compare the normal value of glomerular filtration rate (GFR) in different modalities of single photon emission computed tomography (SPECT). Methods Fifty normal volunteers were divided into 4 groups (aged 20-29, n=14;30-39, n=10;40-49, n=14;50-, n=12). All of the volunteers underwent renal dynamic imaging with MPR SPECT, and single renal GFR value as well as total GFR value was calculated, respectively. The data were compared with GFR values obtained from Starcom 400AC/T SPECT (aged 20-29, n=6;30-39, n=11;40-49, n=7;50-, n=9). Single t test was used to testify the difference of the mean value between the two modalities of SPECT. Results The mean value of single renal GFR in each group of MPR SPECT was (51.03±11.12) ml, (48.44±11.13) ml, (47.79±7.71) ml and (46.54±12.28) ml,while of Starcom 400AC/T SPECT was (57.92±9.03) ml, (57.34±10.33) ml, (55.30±8.51) ml and (44.12±7.94) ml, respectively, and the total renal GFR in each group of MPR SPECT was (102.13±18.33) ml, (96.62±19.90) ml, (95.54±13.04) ml and (92.85±22.83) ml, of Starcom 400AC/T SPECT (115.86±16.51) ml, (113.14±17.71) ml, (110.54±11.13) ml and (88.12±14.41) ml, respectively (all P<0.05). The mean value of single renal GFR was (48.51±10.50) ml and (52.92±10.61) ml, respectively, while the mean value of total renal GFR was (97.04±18.16) ml and (105.63±18.72) ml, respectively (all P<0.05). Conclusion GFR standard value obtained from different SPECT renal dynamic imaging is varied. It is necessory to establish GFR standard value for each type of SPECT.