基于Rabbit2000的终端数据网络传输实现

首先介绍了专门为新一代嵌入式系统设计的高性能8位微处理器Rabbit2000的软硬件特点;对其基于TCP/IP协议的终端数据的软、硬件设计作了简单的分析和介绍,并对网络传输方案予以了说明,给出设计原理框图和有关软件实现方法;对于作为通讯链路的CDMA模块及其相关的AT指令作了较详细的说明,并对相关的C函数做了相应地说明。

Comparative effects of idazoxan, efaroxan, and BU 224 on insulin secretion in the rabbit: Not only interaction with pancreatic imidazoline I2 binding sites

The nature of the binding site(s) involved in the insulin secretory activity of imidazoline compo- unds remains unclear. An imidazoline I2 binding site (I2BS) has been neglected since the classic I2 ligand, idazoxan, does not release insulin. Using the rabbit as an appropriate model for the study of this type of binding sites, we have tried to re-evaluate the effects of idazoxan, the selective I2 compound BU 224, and efaroxan on insulin secretion. Mimicking efaroxan, idazoxan and BU 224 potentiated insulin release from perifused islets in the presence of 8 mM glucose. In static incubation, insulin secretion induced by idazoxan and BU 224 exhibited both dose and glucose dependencies. ATP-sensitive K+ (KATP) channel blockade, though at a different site from the SUR1 receptor, with subsequent Ca2+ entry, mediates the insulin releasing effect of the three ligands. However, additional MAO independent intracellular steps in stimulus- secretion coupling linked to PKA and PKC activation are only involved in the effect of BU 224. Therefore, both an I2 related binding site at the channel level shared by the three ligands and a putative I3-intracellularly located binding site stimulated by BU 224 would be mediating insulin release by these compounds. In vivo experiments reassess the abilities of idazoxan and BU 224 to enhance glucose-induced insulin secretion and to elicit a modest blood glucose lowering response.

Donor's site evaluation after restoration with autografts or synthetic plugs in rabbits

AIM: To investigate donor site's area histological and immunohistochemical knee cartilage appearances after resurfacing iatrogenic defects with biosynthetic plugs orautografts. METHODS: Thirty New Zealand White rabbits were used in this study. A full-thickness cylindrical defect of 4.5 mm(diameter) × 7 mm(depth) was created with a hand drill in the femoral groove of every animal. In Group A(n = 10) the defect of the donor site was re-paired with a biosynthetic osteochondral plug, in Group B(n = 10) with an osteochondral autograft, while in Group C(control group of 10) rabbits were left untreated. RESULTS: Twenty-four weeks postoperatively, smooth articular cartilage was found macroscopically in some trocleas' surfaces; in all others, an articular surface with discontinuities was observed. Twenty-eight out of 30 animals were found with predominantly viable chondrocytes leaving the remaining two-which were found only in the control group- with partially viable chondrocytes. However, histology revealed many statistical differences between the groups as far as the International Cartilage Repair Society(ICRS) categories are concerned. Immunofluoresence also revealed the presence of collagen Ⅱ in all specimens of Group B, whereas in Group A collagen Ⅱ was found in less specimens. In Group C collagen Ⅱwas not found. CONCLUSION: The matrix, cell distribution, subchondral bone and cartilage mineralization ICRS categories showed statistically differences between the three groups. Group A was second, while group B received the best scores; the control group got the worst ICRS scores in these categories. So, the donor site area, when repairing osteochondral lesions with autografting systems, is better amended with osteochondral autograft rather than bone graft substitute implant.

Application of custom anatomy-based nerve conduits on rabbit sciatic nerve defects: in vitro and in vivo evaluations

The intermingling of regenerated nerve fibers inside nerve grafts is the main reason for mismatched nerve fibers. This is one of the key factors affecting limb function recovery after nerve injury. Previous research has shown that the accuracy of axon regeneration can be improved by a bionic structural implant. To this aim, iodine and freeze-drying high-resolution micro-computed tomography was performed to visualize the 3D topography of the New Zealand rabbit sciatic nerve (25 mm). A series of 1-, 2-, 3-, and 4-custom anatomy-based nerve conduits (CANCs) were fabricated based on the anatomical structure of the nerve fascicle. The match index, luminal surface, and mechanical properties of CANCs were evaluated before implanting in a 10-mm gap of the sciatic nerve. Recovery was evaluated by histomorphometric analyses, electrophysiological study, gastrocnemius muscle weight recovery ratio, and behavioral assessments at 12 and 24 weeks postoperatively. The accuracy of nerve regeneration was determined by changes in fluorescence-labeled profile number during simultaneous retrograde tracing. Our results showed that the optimal preprocessing condition for high-resolution micro-computed tomography visualization was treatment of the sciatic nerve with 40% Lugol’s solution for 3 days followed by lyophilization for 2 days. In vitro experiments demonstrated that the match index was highest in the 3-CANC group, followed by the 2-, 1-, and 4-CANC groups. The luminal surface was lowest in the 1-CANC group. Mechanical properties (transverse compressive and bending properties) were higher in the 3- and 4-CANC groups than in the 1-CANC group. In vivo experiments demonstrated that the recovery (morphology of regenerated fibers, compound muscle action potential, gastrocnemius muscle weight recovery ratio, pain-related autotomy behaviors, and range of motion) in the 3-CANC group was superior to the other CANC groups, and achieved the same therapeutic effect as the autograft. The simultaneous retrograde tracing results showed that the percentages of double-labeled profiles of the 2-, 3-, and 4-CANC groups were comparatively lower than that of the 1-CANC group, which indicates that regenerated nerve fascicles were less intermingled in the 2-, 3-, and 4-CANC groups. These findings demonstrate that the visualization of the rabbit sciatic nerve can be achieved by iodine and freeze-drying high-resolution micro-computed tomography, and that this method can be used to design CANCs with different channels that are based on the anatomical structure of the nerve. Compared with the 1-CANC, 3-CANC had a higher match index and luminal surface, and improved the accuracy of nerve regeneration by limiting the intermingling of the regenerated fascicles. All procedures were approved by the Animal Care and Use Committee, Xinjiang Medical University, China on April 4, 2017 (ethics approval No. IACUC20170315-02).

PIP, Not FiO₂Regulates Expression of MMP-9 in the Newborn Rabbit VILI with Different Mechanical Ventilation Strategies

Background: Results from experimental and clinical studies have shown that mechanical ventilation or/and hyperoxia may aggravate a pre-existing lung injury or even cause lung injury in healthy lungs by affecting the expression of MMP-9, but the MMP-9 effects are controversial. How are MMP-9 regulated when multicausative factors of injury such as different FiO2, PIP, and respiratory time (RT) impose simultaneously on lungs? Methods: Newborn New Zealand white rabbits were randomly allocated to an unventilated air control group or to one of the 2 × 3 × 3 ventilation strategies by using a factorial design, with different FiO2, PIP, and RT. Then, lung wet-to-dry ratio (W/D), lung histopathology scores, transmission electron microscope, and cells in BALF were analyzed in these different groups. MMP-9 levels were studied by immunohistochemistry and ELISA. Results: MMP-9 levels were significantly different among 3 PIP ventilation regimes (F = 7.215) and MPIP group was the highest among 3 PIP groups. The lung histopathology score in 100% oxygen was significantly higher than in 45% oxygen group (F = 9.037) and MPIP group was the lowest among 3 PIP groups (F = 57.515) and RT 6 h was more serious than RT 1 h. MMP-9 positively correlated with monocytes, but negatively correlated with neutrophils and lung injury histopathology scores. Conclusions: Different PIP and FiO2 exert simultaneously on newborn lung in newborn rabbits ventilation, only mechanical stretch stimulation affects MMP-9 synthesis. Advisable mechanical stretch can promote MMP-9 expression and has protective role in lung in VILI. HPIP causes barotraumas and LPIP induces atelectrauma.

TRH microinjection into DVC enhances motility of rabbits gallbladder via vagus nerve

AIM To investigate the effects of TRH in DVC on motility of the gallbladder in rabbits. METHODS After fasted for 15h - 18h , rabbits were anesthetized with urethane (1 0g/kg) . Gallbladder pressure (GP) was measured by a frog bladder perfused with normal saline. RESULTS After microinjection of TRH (8 8nmol, 1μl ) into DVC, GP was raised and the frequency of phasic contraction of gallbladder (FPCGB) increased. All the doses of TRH (0 13, 0 25, 0 50, 0 80, 1 30nmol , 1μl ) injected into DVC could excite the motility of gallblader. As the dose of TRH was enlarged, the amplitude and duration of the reaction increased. Effects of TRH in DVC on motility of the gallbladder could be completely abolished by atropine ( 0 2mg/g , i.v.) or vagotomy, but could not be inhibited by phentolamine iv (1 5mg/g) or propranolol iv (1.5mg/g) or by transecting the spinal cord. CONCLUSION Thyrotropin releasing hormone in DVC can excite motility of gallbladder. This effect was mediated by vagus nerves and peripheral M receptor. Its physiological significance may be related to maintaining the phasic contraction of gallbladder in interdigestive period.

Ethanol inhibits the motility of rabbit sphincter of Oddi in vitro

AIM:The rote of the sphincter of Oddi(SO)in ethanol (ETOH)-induced pancreatitis is controversial.Our aim was to characterise the effect of E-I-OH on basal and stimulated SO motility. METHODS:SOs removed from white rabbits were placed in an organ bath(Krebs solution,pH7.4,37℃).The effects of 2 mL/L,4 mL/L,6 mL/L and 8 mL/L of ETOH on the contractile responses of the sphincter were determined. SOs were stimulated with either 0.1 μmol/L carbachol,1 μmol/L erythromycin or 0.1 μmol/L cholecystokinin(CCK). RESULTS:ETOH at a dose of 4 mL/L significantly decreased the baseline contractile amplitude from 11.98±0.05 mN to 11.19±0.07 mN.However,no significant changes in the contractile frequency were observed.ETOH(0.6%) significantly decreased both the baseline amplitude and the frequency compared to the control group(10.50±0.01 mN, 12.13±0.10 mN and 3.53±0.13 c/min,5.5±0.13 cycles(c)/min, respectively).Moreover,0.8% of ETOH resulted in complete relaxation of the SO.Carbachol(0.1 μmol/L)or erythromycin (1 μmol/L)stimulated the baseline amplitudes(by 82% and 75%,respectively)and the contractile frequencies (by 150% and 106%,respectively).In the carbachol or erythromydn-stimulated groups 2-6 mL/L of E-IOH significantly inhibited both the amplitude and the frequency.Interestingly, a 4-5 min administration of 6 mL/L ETOH suddenly and completely relaxed the SO.CCK(0.1 μmol/L)stimulated the baseline amplitude from 12.37±0.05 mN to 27.40±1.82 mN within 1.60±0.24 min.After this peak,the amplitude decreased to 17.17±0.22 mN and remained constant during the experiment.The frequency peaked at 12.8±0.2 c/min, after which the constant frequency was 9.43±0.24 c/min throughout the rest of the experiment.ETOH at a dose of 4 mL/L significantly decreased the amplitude from 16.13±0.23 mN to 14.93±0.19 mN.However,no significant changes in the contractile frequency were observed.ETOH at a dose of 6 mL/L inhibited both the amplitudes and the frequencies in the CCK-stimulated group,while 8 mL/L of ETOH completely relaxed the SO. CONCLUSION:ETOH strongly inhibits the basal,carbachol, erythromycin,and CCK-stimulated rabbit SO motility. Therefore,it is possible that during alcohol-intake the relaxed SO opens the way for pancreatic fluid to flow out into the duodenum in rabbits.This relaxation of the SO may protect the pancreas against alcohol-induced damage.

Effects of octreotide on acute necrotizing pancreatitis in rabbits

AIM:To assess the role of oxygen-derived free radicals and cytokines in the pathogenesis of taurocholic acid-induced acute pancreatitis,and to evaluate the preventive effects of octreotide towards the development of acute pancreatitis. METHODS:Acute pancreatitis was induced in male New Zealand white rabbits by retrograde injection of 0.8 mL/kg·b.m,of 50 g/L sodium taurocholate (NaTC) in the pancreatic duct.Sham- operated animals served as control.Octreotide i mg/kg·b.m. was administered subcutaneously before the induction of pancreatitis.Blood was taken from the jugular vein before and at 1,3,6,12 and 24 h after pancreatitis induction. Serum activities of amylase,IL-6 and TNF-α and levels of malonyl dialdehyde (MDA),glutathione (GSH),glutathione peroxidase (GPx),catalase and superoxide dismutase (Mn-, Cu-,and Zn-SOD) in pancreatic tissue were measured. RESULTS:Serum TNF-α and IL-6 levels increased significantly 3 h after the onset of pancreatitis,and then returned to control level.The tissue concentration of MDA was significantly elevated at 24 h,while the GSH level and GP-x,catalase,Mn-SOD,Cu-,Zn-SOD activities were all significantly decreased in animals with pancreatitis as compared to the control.Octreotide pretreatmnent significantly reversed the changes in cytokines and reactive oxygen metabolites.Octreotide treatment did not alter the serum amylase activity and did not have any beneficial effects on the development of histopathological changes. CONCLUSION:Oxygen-derived free radicals and proinflammatory cytokines are generated at an early stage of NaTc-induced acute pancreatitis in rabbits.Prophylactic octreotide treatment can prevent release of cytokines and generation of reactive oxygen metabolites,but does not have any beneficial effects on the development of necrotizing pancreatitis.

REDUCING HAIRFALLING AND PILLING STUDY IN RABBIT HAIR/WOOL WORSTED KNITWEAR——CHOOSING AND EVALUATING OF FINISHING AGENT

In the paper, the effects of reducing hairfalling and pilling were compared in rabbit hair/woolworsted knitwear by adding various finishing agents. Reducing rates of hairfalling and pilling wereof 6.7％—66.7％ and 9.3％—73.5％ respectively, while fabric handle changed from grade 1 to grade5 in 12 treating method groups. To evaluate the severity of hairfalling and pilling and the conditionof fabric handle of knitwear objectively, quantitatively and comprehensively, we advocated usingthe concept of "geueral evaluating value(GEV)". The results indicated that GEVs of acrylategroups were low, but GEVs of silicone resin groups were high, especially the group with finishingagent solution containing 7％ silicone resin No.3 in which reducing rates of pilling and hairfallingwere of 53％ (National standard: grade 4.5) and 62％, respectively, and washing stability was verygood, while knitwear’s fabric handle almost did not change.

The anatomical,electrophysiological and histological observations of muscle contraction units in rabbits:a new perspective on nerve injury and regeneration

In the conventional view a muscle is composed of intermediate structures before its further division into microscopic muscle fibers.Our experiments in mice have confirmed this intermediate structure is composed of the lamella cluster formed by motor endplates,the innervating nerve branches and the corresponding muscle fibers,which can be viewed as an independent structural and functional unit.In this study,we verified the presence of these muscle construction units in rabbits.The results showed that the muscular branch of the femoral nerve sent out 4–6 nerve branches into the quadriceps and the tibial nerve sent out 4–7 nerve branches into the gastrocnemius.When each nerve branch of the femoral nerve was stimulated from the most lateral to the medial,the contraction of the lateral muscle,intermediate muscle and medial muscle of the quadriceps could be induced by electrically stimulating at least one nerve branch.When stimulating each nerve branch of the tibial nerve from the lateral to the medial,the muscle contraction of the lateral muscle 1,lateral muscle 2,lateral muscle 3 and medial muscle of the gastrocnemius could be induced by electrically stimulating at least one nerve branch.Electrical stimulation of each nerve branch resulted in different electromyographical waves recorded in different muscle subgroups.Hematoxylin-eosin staining showed most of the nerve branches around the neuromuscular junctions consisted of one individual neural tract,a few consisted of two or more neural tracts.The muscles of the lower limb in the rabbit can be subdivided into different muscle subgroups,each innervated by different nerve branches,thereby allowing much more complex muscle activities than traditionally stated.Together,the nerve branches and the innervated muscle subgroups can be viewed as an independent structural and functional unit.This study was approved by the Animal Ethics Committee of Peking University People’s Hospital(approval No.2019 PHE027)on October 20,2019.

Spinach aldolase interactions with rabbit, chicken, and fish muscle phosphofructokinase-1

Previous studies showed that rabbit muscle phosphofructokinase-1 (PFK-1) activity losses due to dilution, due to inhibition by ascorbate, and due to some lithium salts were prevented by rabbit muscle aldolase. Chicken PFK-1 and fish PFK-1 interacted with ascorbate and were inhibited, consistent with a previously proposed function that ascorbate facilitates glycogen in resting muscle by inhibiting glycolysis. This report shows that a plant enzyme, spinach aldolase, has the same ability to prevent rabbit muscle PFK-1 activity loses as rabbit muscle aldolase and in some instances it was a better protector from activity losses than rabbit aldolase. Spinach aldolase also protected chicken and fish PFK-1s from inhibitions by ascorbate and from activity losses due to dilution. Prevention of losses PFK-1 activities from animal species by a plant protein, spinach aldolase, suggests an evolutionary conservative relationship between PFK-1s and aldolases.

Tissue Engineered Osteogenesis in Bone Defects by Homologous Osteoblasts Loaded on Sterile Bioresorbable Coral Scaffold in Rabbits

Objectives: This study explores feasibility of tissue-engineered osteogenesis using sterile coral implants loaded with homologous osteoblasts to repair bone defects. Study Design: A unilateral 4 mm transverse dis- continuity defect was produced approximately mid-way along left radius of young female rabbits using ro- tary diamond disc under continuous saline irrigation and stabilised with autoclaved steel miniplate and screws. The defect was then fitted with sterile bioresorbable coral implant loaded with homologous neonatal calvarial osteoblasts or control implants without osteoblasts. All animals underwent radiography immedi- ately post-operative, at weekly intervals for four weeks and at fortnightly intervals thereafter. Operated bones were histologically evaluated for osteogenesis at 12 weeks. Results: Findings demonstrate osteogenesis and complete repair of bioresorbable coral implant by homologous osteoblasts loaded on coral scaffold. Conclu- sions: Single stage surgery using this technique to induce osteogenesis and closure of discontinuity bone de- fects including palatal clefts and peripheral reduction of large craniofacial defects might prove better thera- peutic modality than autologous bone grafting or tissue distraction osteogenesis.

Sutureless end-to-end bowel anastomosis in rabbit using low-power CO_2 laser

The use of laser energy to weld biological tissues and produce sutureless anastomosis has its advantages over conventional silk-sutured anastomosis since it was reported in small vessels[1] and fallopian tubes[2], in the late 1970s. Since then, more investigators have welded a larger variety of tissues[3-13] and have expanded its application to welding trials of entertomies of rabbit and rat small intestine[14-17] Sauer et al[18] reported results from Nd: YAG laser in reconstruction of end-to-end welding in rabbit small intestine. Recently, controlled temperature during YAG and argon laser-assisted welding of entertomies of rabbit and rat was implemented to eliminate exponential increases in the rate of denaturation associated with rapidly increasing temperature[19，20]. Yet there was no report of sutureless end-to-end bowel anastomosis using low-power CO2 laser. This is a report of a circumferential end-to-end laser welding bowel anastomosis in rabbit by using 3 different CO2 laser powers to explore the feasibility of CO2 laser welding of a circumferential intestinal tissue and to determine the optimal laser-welding parameter. Then the appropriate CO2 laser power was chosen to weld bowels in rabbit and its long-term healing effect was evaluated.

EFFECTS OF ELECTRO ACUPUNCTURE AT NEIGUAN ON MYOCARDIAL MICROCIRCULATION IN RABBITS WITH ACUTE MYOCARDIAL ISCHEMIA

This paper reports the effects of electroacupuncture (EA) at Neiguan (P 6) on myocardial microcirculation and electrical activity observed in rabbits with acute myocardial ischemia (AMI) by employing the vascular casting method and taking monophasic action potential (MAP) as an index. It was found that in the ischemic border zone of the heart, the electrical excitability was strengthened, the shortening of the phase repolarization inhibited, and the number of the micrangia increased in some degree following EA. This suggests that EA can relieve arteriolospasm, inhibit extreme dilatation of blood capillaries, modulate imbalance of micro-vasomotion of the coronary artery, improve myocardial blood-supply, and promote normalization of electrical activities of the ischemia myocardium. This fact not only elucidates the recovery mechanism of the ischemic myocardium promoted by EA at Neiguan (P 6), but also provides morphological basis for the theory of relationship between Neiguan of the Pericardium Meridian and the heart.

Rabbit Defensin(NP-1) Gene Transformation of Wheat and In Vitro Microbicidal Activity Assay of Transgenic Plants

Monocot high expression vector pBARUNP1, harboring rabbit defensin(NP 1) gene and selective bar gene for resistance to the herbicide Basta, were constructed and then transferred into immature embryos of wheat (“Bobwhite” and “Zhong 60634”)via particle bombardment. Southern and RNA dot blots showed the stable integration and transcription of foreign NP 1 gene in the wheat genome. Furthermore, in vitro microbicidal activity assay indicated the proper translation of defensin. Crude protein extraction of transgenic plants exhibited to some extent cytotoxic to several pathogens including G. saubinetii, B. subtilis, E.coli, and A. tumefaciens.

EFFECTS OF ACUPUNCTURE ON THE PITUITARYTHYROID AXIS IN RABBITS WITH FRACTURE

PURPOSE: To observe the effects of acupuncture on the pituitary-thyroid axis in rabbits with fracture. METHOD: 36 male rabbits with a 3-mm width experimental defect in the middle segment of the left radius were randomly divided into the treatment group and control group, and the changes in serum T3, T4 and TSH contents in different weeks were investigated. RESULTS: Serum T3, T4 and TSH contents in the treatment group all were higher than those in the control group, with statistically significant differences in the contents of T4 and TSH in the second week and T3 content in the fourth week (P

Procyanidin B2 protects against diet-induced obesity and non-alcoholic fatty liver disease via the modulation of the gut microbiota in rabbits

BACKGROUND Procyanidins have beneficial effects on metabolic syndrome and antimicrobial activity,but the mechanisms underlying these effects are unclear.AIM To investigate the effects of procyanidin B2(PB2)on non-alcoholic fatty liver disease and to explore the possible mechanism.METHODS Thirty male New Zealand white rabbits were randomized into three groups.All of them were fed either a high-fat-cholesterol diet(HCD)or chow diet.HCD-fed rabbits were treated with vehicle or PB2 daily for 12 wk.Body weight and food intake were evaluated once a week.Serum biomarkers,such as total cholesterols,triglycerides,and aspartate transaminase,were detected.All rabbits were sacrificed and histological parameters of liver were assessed by hematoxylin and eosin-stained sections.Moreover,several lipogenic genes and gut microbiota(by 16S rRNA sequencing)were investigated to explore the possible mechanism.RESULTS The HCD group had higher body weight,liver index,serum lipid profile,insulin resistance,serum glucose,and hepatic steatosis compared to the CHOW group.PB2 treatment prevented HCD-induced increases in body weight and hypertriglyceridemia in association with triglyceride accumulation in the liver.PB2 also ameliorated low-grade inflammation,which was reflected by serum lipopolysaccharides and improved insulin resistance.In rabbit liver,PB2 prevented the upregulation of steroid response element binding protein 1c and fatty acid synthase and the downregulation of carnitine palmitoyltransferase,compared to the HCD group.Moreover,HCD led to a decrease of Bacteroidetes in gut microbiota.PB2 significantly improved the proportions of Bacteroidetes at the phylum level and Akkermansia at the genus level.CONCLUSION Our results indicate the possible mechanism of PB2 to improve HCD-induced features of metabolic syndrome and provide a new dietary supplement.

Feeding Effect of Codariocalyx gyroides on Meat Rabbits

To explore the feeding effect of Codariocalyx gyroides on meat rabbits, 30 healthy meat rabbits at the age of 50 days were randomly divided into five groups(Ⅰ,Ⅱ,Ⅲ,Ⅳ and Ⅴ), six rabbits each group. Rabbits in experimental groups Ⅰ,Ⅱ,Ⅲ and Ⅳ were fed with different quantita-tive complete formula feed and unlimited fresh grass of C. gyroides, and those in group Ⅴ(control group) were fed with complete formula feed. The indicators such as feed intake and growth performance were measured after 60 d. The results showed that the gaining effects of meat rabbits in ex-perimental groups Ⅳ and Ⅲ were most obvious, and the daily gain reached(25.75 ±3.00) and(24.50±1.95) g, 20.72% and 14.86% higher than those in control group, respectively. The conversion efficiency of dry matter in experimental group Ⅲ was the highest, and only 2.99 g of C. gyroides and compound feed dry matter was consumed for the growth of 1 g of rabbit meat, receiving significant economic benefit.

Changes of circulating TNF and its effects on Pseudomonas aeruginosa septic shock in rabbits

The dynamic changes of tumor necrosis factor (TNF) in the circulating blood and its effects on the severity of Pseudomonas aeruginosa induced septic shock were observed in rabbits. 7×109 and 2×109 P. aeruginosa per ki1ogram body weight were intravenously infused to the rabbits to induce mild and severe septic shock.Particular dynamic characterictics of the changes of the circulating TNF were found during P. aeruginosa septic shock. The increase of TNF level in the circulating blood was closely correlated to the initiation and development of P. aeruginosa shock. It is concluded that TNF plays an important role in the mediation of the pathological manifestations of P. aeruginosa shock.