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1.
The granulosis virus of Pieris brassicae, when applied as a paste to the tip of the abdomen of females, was readily transmitted to their progeny. Mortality of the progeny decreased with increasing time after treatment from 75.6% immediately after contamination to 2.0% on day 16. The overall mortality of progeny was 31.6%. Transmission following contamination of the tip of the male abdomen with a virus paste was less, with a peak of 11% mortality of progeny on day 2. The maximum mortality of progeny following contamination of the female abdomen with a virus dust was 19.3% with an overall mortality of 9.5%. There was no transmission following the contamination of the male abdomen with a virus dust.  相似文献   

2.
A study was made of the development of remote radiation pathology of pancreas in male rats after local irradiation of abdomen with doses of 5, 10 (two fractions of 5 Gy at a 30-day interval) and 15 Gy (three fractions of 5 Gy at a 30-day interval). The clinical and morphological estimates show the dose-dependent development of diabetes mellitus and 1.8-fold shortening of the life span, as compared to biological control.  相似文献   

3.
To understand how bical mechanical chest wall (CW) properties are related to those of the CW as a whole, we measured esophageal and gastric pressures, CW volume changes (measured with a head-out body plethysmograph), and anteroposterior and transverse CW diameter changes (measured with magnetometers attached to the surface) during sinusoidal forcing at the mouth (2.5% vital capacity, 0.5-10 Hz) in four healthy subjects. Total CW resistance decreased sharply as frequency rose to 3-4 Hz and remained relatively constant at higher frequencies. Total CW reactance became less negative with increasing frequency but showed no tendency to change sign. Above 2 Hz, diameters measured at different locations changed asynchronously between and within the rib cage and abdomen. "Local pathway impedances" (ratios of esophageal or gastric pressure to a rate of diameter change) showed frequency dependence similar to that of the total CW less than 3 Hz. Local pathway impedances increased during contraction of respiratory muscles acting on the pathway. We conclude that 1) total CW behavior is mainly a reflection of its individual local properties at less than or equal to 3 Hz, 2) local impedances within the rib cage or within the abdomen can change independently in some situations, and 3) asynchronies that develop within the CW during forcing greater than 3 Hz suggest that two compartments may be insufficient to describe CW properties from impedance measurements.  相似文献   

4.
The physiological reactions of the body in scuba diving situation can be simulated in a pressure chamber by increasing the ambient pressure. In this study the influence of a hyperbaric environment of 6 bar on the changes of the subcutaneous adipose tissue (SAT) thicknesses on different body sites in 68 voluntary men with undersea diving experience was investigated. Measurements of SAT-topography (SAT-Top) were performed with the optical device Lipometer before and after hyperbaric exposure. We observed a significant increase of the SAT-layers of the upper body zones, upper abdomen (+24.5%), lower abdomen (+21%) and front chest (+19%) after hyperbaric exposure. This increase of volume can be assumed to the nitrogen accumulation in fat cells at increased ambient pressures. In conclusion we describe for the first time in detail the influence of a hyperbaric environment on quantitative and topographic changes of SAT.  相似文献   

5.
BACKGROUND: Abdominal sepsis induces a local production of proinflammatory mediators that may trigger both septic shock and organ-system dysfunction. AIMS: The present study analyzed exudation, cell migration, and CD11a and CD18 subset cells of both local and systemic responses induced by fecal peritonitis in mice. METHODS: Animals were anesthetized and, after performing a midline incision in the abdomen, the cecum was ligated and punctured twice with a needle. Sham-operated animals were included. Some groups were previously treated with Evans blue dye (intravenously) to further evaluate the amount of tissue and abdominal cavity leakages. RESULTS: Fecal peritonitis triggered a local inflammatory reaction with an increased number of leukocytes and exudation between 6 and 48 h (p < 0.01). Although CD11a/CD18-positive cells in the abdomen peaked after 24h, a significant decrease of them was detected after 48 h (p < 0.05). At the studied period of time (6-48 h), different degrees of exudation in several organs occurred, whereas a significant late recruitment (24 h) of CD11a/CD18 cells into the lungs was observed. CONCLUSIONS: In this model, cell migration and exudation at the site of injury occurred in parallel. However, in the lungs, the recruitment of leukocytes that express CD11a/CD18 adhesion molecules constitutes a non-dependent event in relation to fluid leakage accumulation at this site.  相似文献   

6.
The abdominal hollowing technique is used for training the transversus abdominis (TrA). However, the optimal intensity of hollowing is still unclear. The objective of the present study is to verify the validity of estimating the tension of the TrA by measuring the girth of the abdomen with a tape and to determine the optimum intensity of hollowing to effectively train the TrA. Sixteen healthy males performed hollowing with an intensity of 0%, 25%, 50%, 75%, and 100%, estimated from the girth of the abdomen. The shear elastic modulus was measured for the rectus abdominis (RA), external oblique (EO), internal oblique (IO), and TrA at all intensities via ultrasonic shear wave elastography. The shear elastic modulus was considered as the index of the tension of the abdominal muscles at each intensity, and the ratio of the TrA to RA, EO, and IO respectively was calculated as the index of TrA selectivity. As the intensity of hollowing increased, the girth of abdomen decreased and tension of all the four muscles increased. The ratio of TrA to the RA, EO, and IO did not exhibit a significant variation among hollowing intensities of 25% to 100%. It is rational to estimate the tension of the TrA by measuring the girth of the abdomen. Moreover, considering both TrA contraction intensity and selectivity, abdominal hollowing performed at maximum intensity was effective for the maximum contraction training of the TrA.  相似文献   

7.
The invasive mosquito Aedes albopictus (Skuse) (Diptera: Culicidae) has become widespread in Italy during the past decade. Also Italy has foci of canine filariasis caused by Dirofilaria (Spirurida: Onchocercidae), due to subcutaneous D. repens Railliet & Henry as well as the dog heartworm D. immitis (Leidy) transmitted by various vector mosquitoes (Diptera: Culicidae). In 2002, at Fiumicino, west of Rome (Lazio Region), 17% of dogs were found to have D. repens microfilariae in peripheral blood. To evaluate the role of Ae. albopictus as a vector of Dirofilaria in this area, female mosquitoes were collected daily, June-October 2002, landing on dog or human bait in a rural house at Focene. Mosquitoes were maintained at 27 degrees C and 70% RH for 6 days, to allow development or purging of filaria larvae, then identified and frozen for subsequent molecular assay with filaria-specific ribosomal S2-S16 primers. To distinguish specimens harbouring infective L3 Dirofilaria larvae, DNA was extracted separately from the mosquito abdomen and head-thorax. Dirofilaria species were identified by sequencing, confirmed by polymerase chain reaction of positive specimens using primers specific for D. immitis and D. repens. Dirofilaria DNA was detected in 3/154 (2%) of Ae. albopictus females examined: D. repens DNA in head-thorax and abdomen of one collected 27th July; D. immitis in the abdomen of one collected 24th September; DNA of both D. immitis and D. repens in the head-thorax of one collected 11th October 2002. Thus Ae. albopictus is a potential vector of both Dirofilarias in Italy, representing risks for veterinary and human health.  相似文献   

8.
Burst abdomen and incisional herniation are continuing problems for the general surgeon. A prospective study was carried out to define the extent of the problem. Over five years from 1975 to 1980 a total of 1129 major laparotomy wounds in adults were assessed at regular intervals for 12 months after operation. There were 19 burst abdomens (1.7%) and 84 incisional hernias (7.4%). The introduction of the mass-closure technique reduced the incidence of burst abdomen from over 3% in 1975 to 0.95% in 1979. It did not, however, improve the rate for incisional hernias, which was 7.6% in 1979. Many factors are associated with incisional herniation: old age, male sex, obesity, bowel surgery, type of suture, chest infection, abdominal distension, and, most important, wound infection. More work is needed to find the ideal method of wound closure, and efforts should be made to eliminate wound infection.  相似文献   

9.
Liver synthesizes thrombopoietin, which is a major cytokine involved in the production of hematopoietic cells. The purpose of this study was to examine the effects of preferential liver irradiation on expression of thrombopoietin and production of hematopoietic cells. About 70% of the liver of C57BL6/J mice was irradiated with 20 Gy of gamma rays. Exposure to ionizing radiation enhanced hematopoietic progenitors and megakaryocyte frequency in bone marrow and induced a transient increase in platelet and neutrophil counts that peaked 14 days after irradiation. The concentration of thrombopoietin was increased in serum as early as 5 h after liver irradiation and was still elevated at day 14. By using Northern blot analysis and an RNase protection assay, we showed that thrombopoietin mRNA was increased in the irradiated liver. To determine whether thrombopoietin was involved in the stimulation of hematopoiesis, we irradiated mice in which thrombopoietin deficiency had been induced by homologous recombination. Platelet levels were increased in both heterozygous and homozygous thrombopoietin-deficient mice with a magnitude similar to that obtained in normal mice. In summary, our data demonstrate that local irradiation of the abdomen encompassing the liver leads to stimulation of hematopoiesis through a thrombopoietin-independent mechanism.  相似文献   

10.
A new device that utilizes the voltages induced in separate coils encircling the rib cage and abdomen by a magnetic field is described for measurement of cross-sectional areas of the human chest wall (rib cage and abdomen) and their variation during breathing. A uniform magnetic field (1.4 X 10(-7) Tesla at 100 kHz) is produced by generating an alternating current at 100 kHz in two square coils, 1.98 m on each side, parallel to the planes of the areas to be measured and placed symmetrically cephalad and caudad to these planes at a mean distance of 0.53 m. We demonstrated that the accuracy of the device on well-defined surfaces (squares, circles, rectangles, ellipses) was within 1% in all cases. Observed errors are due primarily to small inhomogeneities of the magnetic field and variation of the orientation of the coil relative to the field. Using a second magnetic field (80 kHz) perpendicular to the first, we measured the errors due to nonparallel orientation during quiet breathing and inspiratory capacity maneuvers. In 10 normal subjects, orientation effects were less than 2% for the rib cage and less than 0.7% for the abdomen. In five of these subjects, orientation effects at functional residual capacity in lateral and seated postures were generally less than or equal to 5%, but estimated tidal volume during spontaneous breathing was comparable to measurements in the supine posture. In five curarized patients, we assessed the linearity of volume-motion relationships of the rib cage and abdomen, comparing cross-sectional area and circumference measurements. Departures from linearity using cross-sectional areas were only one-third of those using circumferences. In seven normal subjects we compared cross-sectional area measurements with respiratory inductive plethysmography (RIP) and found comparable estimates of lung volume change over a wide range of relative rib cage contributions to tidal volume (-5 to 105%), with slightly higher standard deviations for the RIP (SD = 10% for RIP; SD = 4% for cross-sectional area).  相似文献   

11.
The general female bias in body size of animals is usually attributed to fecundity selection. While many studies have demonstrated a positive relationship between body size and fecundity, the most common interpretation of fecundity selection is that larger females have larger abdomens and can hold more eggs, yet the relationship between abdomen size and fecundity has rarely been examined. For the waterstrider, Aquarius remigis, we find a significant relationship between body size and fecundity and demonstrate that the target of fecundity selection is abdomen size. Thus, larger females have higher fecundities because they have larger abdomens and not because of their total size per se. The rate at which fecundity increases with increasing abdomen size exceeds that which would be expected due to a simple volume constraint and suggests that other factors, such as increased ability to obtain resources, may contribute to the increase in fecundity with body size. Selection intensities estimated from our data indicate that fecundity selection could be a significant selective force on both total and abdomen lengths. Previous studies have found that abdomen size increased faster than body size and thus, larger females had relatively larger abdomens. The relationship of abdomen length and thorax length in A. remigis is hypoallometric and indicates that larger females have relatively smaller abdomens. We hypothesize that this may reflect conservation of abdomen size in females developing under poor conditions. Finally, while egg size is not directly related to body size, we find a trade-off between egg size and number when female abdomen length is held constant, suggesting that selection on egg size may influence abdomen length only indirectly through its effects on fecundity.  相似文献   

12.
S P Grozdov 《Radiobiologiia》1987,27(5):657-662
Injections of oxidized glutathione (40 mg/kg, 5-7 days) combined with the parenteral nutrition (PN) of rats after local X-irradiation of abdomen (13-14.5 Gy) increased significantly the survival rate, decreased the gastrointestinal syndrome manifestations, and intensified the assimilation of a PF amino acid component. The reduced glutathione had no effect.  相似文献   

13.
Two phases of allometry, prepubertal, and pubertal, are evident in A. bahia, equally dividing the first six instars. Coefficients of variation of the sizes of individuals’ abdomens, carapaces, and standard lengths significantly decrease in intermolt four, suggesting a synchronization of the size at which individuals enter the pubertal phase. Growth in standard length is best expressed over the first six post-larval instars by a quadratic equation, but within instars 85%, or more, of the expansion occurs linearly during the intermolt period, with only about 15% occurring during ecdysis. Estimations of carapace:abdomen allometry indicate an average ratio of 1:1.97 during the intermolt and 1:1.68 during ecdysis. The average molt:intermolt ratio in the carapace expansion is 1:3.16, and in the abdomen, 1:3.71, indicating that proportional growth between the carapace and the abdomen is continuous during both the intermolt and molt phases, but occur at different rates and proportions during the two periods.  相似文献   

14.
Induction plethysmography (IP) utilizes changes in the inductance of sinusoidal wires embedded in elastic bands placed around the chest and abdomen to detect volume changes in the two compartments. These changes can be attributed to respiration or heart beat. To date, most applications have been tailored to an investigation of respiration. More sensitive systems have been employed for the detection of cardiac activity. The wires within the bands, which function as the coil in a resonant circuit, are excited by an oscillator. Among other factors, the inductance of the coil depends on the cross-sectional area of the coie, and changes with respiration in coils placed around the chest and abdomen. Using LabView software, the biosignals obtained undergo an analog-to-digital conversion prior to processing. The system was calibrated using the isovolume method. In 10 adults, IP was tested against a pneumotachograph (PNT) in different body positions (standing, sitting, supine, prone). Correlation between tidal volumes measured with IP and PNT was of r > or = 0.96 on average, recalibration being done after each change in position. The absolute mean error ranged between 3.7 and 8.5%, depending on body position. The smallest error (3.7%) and greatest agreement between the two methods was found in the supine position (93.3% of the IP measurements within +/- 10% of the PNT measurements). An IP application that could be used to collect data over the long term and which is in good agreement with PNT was developed by employing a "virtual instrument" (VI, LabView) for flexible data acquisition and data processing. Agreement was best when the volunteer adopted a supine position. A smaller correlation was found in standing or seated subjects. This might be due to the fact that in the latter two positions, the respiratory system may have more than 2 degrees of freedom, and thus cannot be adequately monitored by only two bands around the thorax and abdomen. Signals produced by cardiac activity were detectable on the surface of the body.  相似文献   

15.
ABSTRACT: INTRODUCTION: Torsion of the gallbladder is an extremely rare cause of acute abdomen, which commonly affects thin elderly women. A prompt surgical approach is necessary to avoid fatal complications associated with gangrene and perforation of the gallbladder. However, it is difficult to make a preoperative diagnosis using ordinary imaging modalities. CASE PRESENTATION: An 84-year-old Japanese woman was admitted to our hospital due to left lower abdominal pain. Her pain shifted suddenly to the right upper abdomen a half day after admission. Although her enlarged and wall-thickened gallbladder had been already seen at admission, it rotated approximately 180 degrees and deviated to the midline of her abdomen on the second computed tomography scan, which helped us to make a correct diagnosis of gallbladder torsion. The patient underwent an emergency operation (detorsion and cholecystectomy) and recovered without any complications. The gallbladder had necrosis due to torsion. CONCLUSION: Sequential diagnostic imaging might be helpful to make a preoperative diagnosis of gallbladder torsion when the gallbladder is enlarged and wall thickened but the patient does not present with typical clinical symptoms.  相似文献   

16.
Volume averaged CT dose index (CTDIvol) is an important dose index utilized for CT dosimetry. Measurements of CTDIvol are performed in reference cylindrical phantoms of specified diameters. A size-specific dose estimate (SSDE) has been recommended for assessment of doses delivered to individual patients. Evaluation of the SSDE requires the size of the scanned region of the patient to be estimated in terms of water-equivalent diameter (Dw) to allow calculation of a dose value appropriate for the patient. Estimation of Dw, however, may be challenging and time consuming as it requires assessment of Dw for each slice within the scanned region. A study has been carried out to investigate the suitability of using Dw,mid for a single slice at the middle of the scanned region to estimate a value of Dw,mean to apply to all slices. 351 phantoms (158 paediatric and 193 adult) developed from reconstructed CT images of patients were employed. Six scan regions were studied: chest, abdomen, pelvis, chest and abdomen, abdomen and pelvis, and the whole trunk. Results show that the use of Dw,mid can lead to over or underestimation of Dw,mean by up to 13% for paediatric and adult patients. SSDE values based on Dw,mid and Dw,mean were assessed for each phantom, and a linear regression analysis was performed. Use of the analysis could provide a simple and practical approach to assessing SSDE for a given scan based on Dw,mid with the root-mean-square errors estimated to be in the range of 1.2%–4.0% for paediatric and 1.2%–5.9% for adults.  相似文献   

17.
Methods have been developed to measure the synthesis of glycerol-3-phosphate dehydrogenase (GPDH) during the development of Drosophila melanogaster. In emerged adult flies, GPDH is a principal component of protein synthesis, comprising between 1 and 2% of the protein synthetic effort. This high relative rate of protein synthesis continues throughout adult life during a period of stable enzyme concentration. Therefore, it is evident that GPDH undergoes continual turnover. Analysis of GPDH synthesis in the adult segments reveals that this enzyme is synthesized in head, thorax, and abdomen. In 5-day-old flies, the relative rates of GPDH synthesis in the thorax and abdomen are similar. However, the concentration of GPDH in the thorax greatly exceeds that found in the abdomen. Therefore, it appears that the turnover rate of GPDH in the abdomen must be greater than the turnover rate of GPDH in the GPDH-containing cells (flight muscle) of the thorax. GPDH represents between 0.5 and 0.9% of the protein synthetic effort of larvae. The principle GPDH-containing tissue of larvae is fat body. The turnover of GPDH in larvae is similar to that in adult abdomen. This may be related to the concurrent presence of GPDH isozyme-3 in both tissues. Our studies indicate that the cell type-specific control of GPDH occurs at several levels.  相似文献   

18.
19.
Measurements of action potentials recorded from giant nerve fibres of the crayfish abdomen showed that by addition of an organic acid salt to a local anaesthetic solution, the onset of anaesthetic action became more rapid and the duration of action was prolonged. Similar results were also obtained in rat vagal nerves. The chemical structure of compounds having these enhancing effects was found to have, in common, a carboxyl group connected with either a benzene ring or an aliphatic hydrocarbon. Topical application of anaesthetic solutions to the skin of flexor side of the forearm in humans revealed that the duration of anaesthesia evaluated by the apparent decrease of the number of pain points was significantly prolonged by the addition of salicylate. The use of local anaesthetics combined with organic acid salts would be promising in clinical practice to enhance their action greatly.  相似文献   

20.
Sabellid and sabellariid polychaetes are regarded as sister groups in a number of recent phylogenetic analyses. This is based mainly on a shared specific arrangement of chaetae referred to as chaetal inversion. Remarkably, the uncini have a notopodial position in the abdomen, whereas capillary chaetae occur in the neuropodia in both taxa in contrast to the situation in putative relatives. However, in sabellids uncini and capillary chaetae change their position completely at the border between thorax and abdomen, whereas uncini are missing in the parathorax of Sabellariidae. Due to this difference the significance of the chaetal inversion for systematics has been subject to discussion for years. Serial semithin sections of parapodia of the Sabellidae Sabella pavonina, Branchiomma bombyx, Fabricia stellaris, and of the Sabellariidae Sabellaria alveolata were studied in order to obtain detailed information on their chaetal arrangement and sites of chaetal origin. SEM investigations and computer-aided 3D-reconstructions provide deep insight into the spatial organization of the rami. Though differing externally, the principal chaetal arrangement and the location of the formative sites turned out to be almost identical within the species of Sabellidae. Most chaetae are aligned in straight transverse rows with a dorsal site of origin within neuropodia and a ventral one in notopodia as is common in sedentary polychaetes. Semicircular and spiral arrangements are revealed to be modified transverse rows. Only in thoracic notopodia does an additional dorsocaudal formative site form distinct rows. The chaetal inversion in Sabellidae is additionally characterized by an abrupt change of capillary chaetae and uncini along with a sudden change of the parapodial morphology at the border between thorax and abdomen. All chaetae of S. alveolata are aligned in transverse rows with the same location of the formative sites as in sabellids and other sedentary polychaetes. However, in contrast to sabellids the chaetae are not inverted across a parathoracic abdominal border. Moreover, there is no inversion of the parapodial structure from parathorax to abdomen and the neuropodial chaetal composition changes gradually from parathorax to abdomen. The chaetal arrangement in Sabellariidae thus cannot be described as inverted along the body-axis as in Sabellidae. Evolutionary steps implied by the assumption of an inverted chaetal pattern in a supposed common ancestor are discussed. It is concluded that the specific chaetal arrangement of Sabellidae and Sabellariidae arose independently and therefore provides no support for a sistergroup relationship of sabellids and sabellariids.  相似文献   

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