It is difficult to select the appropriate ventilation mode in clinical mechanical ventilation. This paper presents a nonlinear multi-compartment lung model to solve the difficulty. The purpose is to optimize respiratory airflow patterns and get the minimum of the work of inspiratory phrase and lung volume acceleration, minimum of the elastic potential energy and rapidity of airflow rate changes of expiratory phrase. Sigmoidal function is used to smooth the respiratory function of nonlinear equations. The equations are established to solve nonlinear boundary conditions BVP, and finally the problem was solved with gradient descent method. Experimental results showed that lung volume and the rate of airflow after optimization had good sensitivity and convergence speed. The results provide a theoretical basis for the development of multivariable controller monitoring critically ill mechanically ventilated patients.
Exhalation ; Humans ; Lung ; physiology ; Models, Biological ; Nonlinear Dynamics ; Pulmonary Ventilation ; Respiration ; Respiration, Artificial ; Tidal Volume

Cyclophosphamide (CPA) is the most common alkylating antineoplastic agent, as well as a strong immunosuppressant that is frequently applied to autoimmune diseases and organ transplantation. It is metabolized by cytochrome P450 oxidases (CYPs) to its active metabolite which played a critical role in therapy. CPA has serious and even fatal side effects, and its efficacy and adverse reactions are significantly varied among individuals. In this review, the association of the genetic polymorphisms in the metabolic enzymes and transporters involved in the disposition of CPA with the efficacy and adverse effects of CPA were summarized, thereby providing fundamental reference for further pharmacogenomic study of CPA.

Objective To explore artifactual responses of auditory steady-state reponses (ASSRs) to bone-conduction stimuli.Methods The present study involved a group of subjects,aged between 5 to 39 months,with bilateral profound sensorineural hearing losse.Recorded were the reponses to multiple bone-conducted 0.5,1,2,4 kHz tone pips repeated at the rates of 77～101 Hz.All the subjects were sedated by Hydrate Chloride during the testing.Results Artifactual ASSRs were seen at 115 and 100.5 dB (re:1?N) (The above levels are equivalent to around 60 dB HL) at 1 and 4 kHz.No artifactual responses were recorded at 0.5 and 2 kHz stimuli at the maximum output level.Conclusion Bone-conducted hearing loss greater than moderate can not be tested reliablely due to artifactual responses and lower maximum output level than that of air conduction.

Objective To observe the substance P(SP) and calcitonin gene-related peptide(CGRP) expressions in the temporomandibular joints(TM J) of the rats undergone emotional stress and explore the relationship between emotional stress and temporomandibular joint disorder(TMD). Methods Ninety SD rats were averagely randomly divided into emotional stress ( ES ) group( n = 30 ), electric foot-shocked (FS) group ( n = 30 ) and control (CON) group( n = 30). The emotional stress was induced by communication box. The TMJ tissues in ES and CON groups were removed after 1, 3 and 5 weeks of emotional stress for scanning electron microscope ( SEM ) test and immunohistochemistry test. The SP and CGRP expressions were examined with SABC immunohistochemistry and then analyzed by image analysis system. Results The expressions of SP and CGRP had significant difference after 1 ,3 and 5 weeks emotional stress ( SP: 124.5 ± 16.9,185.6 ± 1.8 and 193.5 ± 3.5, respectively; CGRP: 185.9 ±5.3, 112.5 ±5.2 and 174.3 ±5.3 ,respectively) (P＜0. 05 ). The SEM results showed that there was a series of structural change on the condylar surface after emotional stress. Conclusion The SP and CGRP energy nerve fibers take part in the TMJ pathological process undergone emotional stress.

Objective To investigate the value of multipoint and multidirectional ultrasound-guided fineneedle aspiration cytology (US-FNAC) in preoperative diagnosis of papillary thyroid microcarcinoma (PTMC).Methods From Jan.2012 to Jan.2013,multipoint and multidirectional US-FNAC were performed in 177 patients with 233 nodules suspected as PTMC,and the cytopathological findings were compared with surgical pathological results and clinical follow-up results.Results Of the 233 biopsies,the cytology were classified as malignant for 146 lesions,suspicious for malignancy for 43 lesions,benign for 24 lesions,follicular lesions for 4 lesions and inadequate sample for 16 lesions.After the second multipoint and multidirectional US-FNAC,only 1 case did not have sufficient cells for diagnosis,and the puncture failure rate was 0.43％.Actually there were 189 malignant and 44 benign lesions confirmed by clinical follow-up and pathological results.The sensitivity,specificity,and accuracy of multipoint and multidirectional US-FNAC was 99.5％,81.8％ and 96.1％ respectively.Conclusions Multipoint and multidirectional US-FNAC has definite value in increasing puncture qualified rate and positive diagnosis rate before operation.

Objective To investigate the contribution of Cystatin C to the preoperative diagnosis and clinical therapy of gastroenteric tumor.Methods Using surgical materials from patients with stomach, colon and rectum cancer, immunohistochemisty, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting analysis were performed with antibodies against Cystatin C.Cystatin C of the cancerous and paired noncancerous lesions were determined by enzyme-linked immunosorbent assay (ELISA).Results (1)Immunohistochemical staining of Cystatin C was evident expression in cancer cells and associated stromal tissues, this was not the case in paired noncancerous tissues,there were also statistical relationship between the expression of Cystatin C in cancerous and that in noncancerous tissues (?~2=6.825,P

OBJECTIVE： To analyze the trend of costs of various drugs consumed in hospitals of Guangzhou METHODS： The data were derived from the Hospital Purchasing of Drug Information System in Guangzhou from 1997 to 2000 The expense of each drug was calculated at the price of that year RESULTS： The annual increasing rates of drug expenses in 1998， 1999 and 2000 were 17 01％ ， 24 49％ ， 23 11％ respectively CONCLUSION： It is a matter of great urgency to rationally use drugs， to eliminate the waste of resources and to lighten the patients'burden

Objective To investigate the role of psychological intervention in the prevention of the temporomandibular joint disease (TMD) , through the observation of the relative changes in the rat TMJ under psychological stress after psychological intervention. Methods The rat model of communication box was built to exert the psychological stress. The antianxiety agent was applied before stress, and the stressor was removed after stress. The expression of the proinflammatory cytokines IL-1 and TNF-α in the mandibular condylar chondrocytes in rat TMJ was detected by ELISA and RT-PCR. Results The RT-PCR results showed that the expression of IL-1 mR-NA increased into the peak in the 1st week, weakened in the 3rd week, and returned to normal in the 5th week, while the TNF-αmRNA peaked in the 1st week, returned to normal in the 3rd week. The ELISA results showed that there was no significant difference of the OD value of the serum IL-1 and TNF-α(0. 095 ±0. 006,0. 077 ± 0.007,0.069 ±0.009 ;0.079 ±0.010,0.075 ±0. 009,0.079 ± 0.012) in the antianxiety agent group (0. 107 ± 0.024,0. 101 ±0.005,0.088 ±0.010)and the stressor removal group(0. 090 ±0.016,0. 088 ±0.005,0.089 ± 0.011) , compared with the control group(0.087 ±0.004,0.090 ±0.009,0.089 ±0.010;0.074 ±0.008,0.069 ±0.015,0.068 ±0.011) (P>0.05), while significant differences were observed when compared with the psychological stress group(0.282 ±0.045,0.226 ±0.021,0.092 ±0.002;0. 164 ±0.009,0.123 ±0.013,0.091 ± 0.006) (P<0.05 ). Conclusion Application of the antianxiety agent and stressor removal could effectively counter the influence of psychological stress to TMJ, which provides good experience for the clinical prevention of TMD.

OBJECTIVE:To analyze the trend of costs of various drugs consumed in hospitals of Guangzhou METHODS:The data were derived from the Hospital Purchasing of Drug Information System in Guangzhou from 1997 to 2000 The expense of each drug was calculated at the price of that year RESULTS:The annual increasing rates of drug expenses in 1998,1999 and 2000 were 17 01%,24 49%,23 11% respectively CONCLUSION:It is a matter of great urgency to rationally use drugs,to eliminate the waste of resources and to lighten the patients'burden

Objective To observe the cerebral activation pattern in patients with cervical dystonia (CD) during finger movements and the changes caused by botulinum toxin injection by functional MRI.The possible etiological mechanism of CD and effect of peripheral botulinum toxin treatment on the level of central nerves system are investigated.Methods A designed functional MRI block with complex finger movements was applied and 11 patients with CD as well as 11 age and gender matched controls were scanned.Compare the activation pattern of CD pre/post treatment groups versus health controls.Evaluate and compare the symtom severity with Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS).Make a correlation analysis between activation pattern alteration and TWSTRS change in CD pre/post treatment groups.Results An reduced extent of activation in patients with CD was demonstrated compared to healthy controls in ipsilateral putamen,prefrontal cortex and contralateral somatosensory cortex to the direction of the head deviation,while an elevated extent of activation in ipsilateral precuneus and fusiform with statistic significance.At the time point of 4 weeks after botulinum toxin treatment patients showed no evident difference with healthy controls except for the decreased activation in contralateral precuneus to the direction of the head deviation.TWSTRS of patients with CD decreased from (20.02 ± 5.52) to (4.11 ± 4.34) with statistic significance (t =11.71,P =0.000) after botulinum toxin treatment.There was a positive correlation between cerebral activation pattern change in some cerebral areas (ipsilateral primary somatosensory cortex,premotor cortex,supplementary motor cortex,insula,fusiform,hippocampus with parahippocampa as well as contralateral middle temporal cortex and hippocampus with parahippocampa to the direction of the head deviation) and TWSTRS score decrease.Conclusions There are widespread abnormalities in cortical and subcortical activation pattern in patients with CD,which might due to dysfunction of sensory-motor integration.We speculate a basic pre-dystonic state is present in affected body parts prior to clinical symptoms appear.Botulinum toxin fulfills its subsequent central effect by reorganizing and normalizing the cerebral cortex in patients with CD.