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11.
In New Zealand white rabbits bearing the transplantable VX2 carcinoma intramuscularly in the hind limbs uniformly a granulocytosis syndrome developed, characterized by peripheral blood neutrophilia and marked granulocytic bone marrow hyperplasia, whereas the syndrome did not always develop in animals bearing the tumor intraabdominally. The relationship between the extent of pulmonary metastases and granulocytosis/bone marrow hyperplasia was significant (P less than 0.005). This positive correlation (correlation coefficient = 0.85) existed for both animals bearing intraabdominal tumors and animals bearing intramuscular tumors. The granulocytic syndrome occasionally occurred in rabbits with mild degrees of pulmonary metastatic involvement, but never with total absence of pulmonary metastases. Hypercalcemia occurred prior to the appearance of pulmonary metastases and was not essential to the development of granulocytosis. These data suggest that granulocytosis in VX2 carcinoma-bearing rabbits is dependent on the presence of tumor in the lungs and is not directly related to implantation site. This tumor-bearing animal model may be suitable for studies of tumor-associated granulocytosis in vivo.  相似文献   
12.
Chlamydial pneumonitis induced in newborn guinea pigs.   总被引:1,自引:0,他引:1       下载免费PDF全文
One- to three-day-old guinea pigs were inoculated intranasally with the chlamydial agent of guinea pig inclusion conjunctivitis. Physical signs of infection included a marked increase in respiration rate on days 5 to 10 of infection and radiographic evidence of pneumonia on day 6. When animals were killed at various times after infection and lung tissue was examined by histopathology, evidence of pneumonia was found beginning on day 4 and lasting as long as day 12, with maximal pathological changes on days 6 to 8. The pneumonia was generally unilateral and consisted of an acute inflammatory component in the bronchioles with granulocytes in both the lumen and the wall of the bronchioles and an interstitial and intra-alveolar mononuclear infiltrate in the parenchyma of the lung. Chlamydial antigen was detected in the bronchial epithelial cells by immunoperoxidase staining, and the guinea pig inclusion conjunctivitis organism was isolated from lung tissue on days 6 to 9. No other significant bacteria were isolated from lung tissue or seen on gram stains of lung sections. Both immunoglobulin M and immunoglobulin G serum antibodies to the guinea pig inclusion conjunctivitis agent were detected as early as day 8 and reached peak levels on day 12. The infection was apparently self-limiting. This model presents the opportunity to investigate pathophysiological and immunological aspects of chlamydial respiratory infections in a neonatal animal.  相似文献   
13.
The nitric oxide pathway in pre-eclampsia: pathophysiological implications   总被引:2,自引:0,他引:2  
Pre-eclampsia, one of the most significant health problems inhuman pregnancy, complicates 6-7% of all gestations and is theleading cause of fetal growth retardation, infant morbidityand mortality, premature birth and maternal death. Recent researchimplicates free radicals in the pathophysiology of pre-eclampsia.This review covers the biochemistry of nitric oxide (NO) andpossible interactions with other free radicals. Studies in therat show that pregnancy is associated with enhanced productionand responsiveness to NO in both reproductive tissues and bloodvessels. Rats infused with NG-nitro-L-arginine methyl ester(L-NAME, a NO synthase inhibitor) have been used as an animalmodel of pre-eclampsia, and the effects of steroid hormoneson blood pressure in this model have been tested. Results suggestthat pre-eclampsia may be a state of NO deficiency. However,in humans there seem to be contradictions regarding the involvementof NO in maternal adaptation to pregnancy. It is suggested thatNO may be one of several systems that act in concert to maintaina symbiotic relationship between mother and fetus. However,the input of each system may be genetically determined.  相似文献   
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Rigor and resistance to stretch in vertebrate smooth muscle   总被引:2,自引:0,他引:2  
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Human 19S IgM was digested with pronase and proteinase K. Proteolysis was relatively fast, producing Fab2 mu-like fragments (approx. mol. wt 114,000) and Fab mu-like fragments (approx. mol. wt 46,500) as major products. Immunochemical analysis indicated that the fragments produced by either enzyme are very similar and that they are produced by cleavage at the C mu 2-C mu 3 and C mu 1-C mu 2 domain junctions respectively. An intermediate species of mol. wt 74,300, immunologically identical to F(ab)2 mu, was also identified. This is thought to represent an F(ab)2 mu fragment with one Fab mu fragment removed. Fc mu-related fragments were not identified in the digestion mixture with either enzyme. Covalently linked and non-covalently linked 7S human IgM (IgMs and IgMr respectively) were digested with pronase and proteinase K. IgMs was degraded very rapidly by either enzyme, producing relatively stable F(ab)2 mu- and Fab mu-like fragments. These fragments were similar in mol. wt and immunochemical properties to those produced from 19S IgM. IgMr was also degraded rapidly by either enzyme, in this case producing Fab mu-like fragments with no detectable F(ab)2 mu-like fragments. The kinetics of digestion and nature of the products suggest that cleavage of 19S IgM by pronase or proteinase K proceeds via an initial attack at the C mu 2-C mu 3 junction, followed by further degradation at the Cmu 1-C mu 2 junction. The results obtained using 7S IgM show that the intersubunit disulphide bonds, and the associated pentameric structure, are responsible for the relative resistance of 19S IgM to proteolysis. The inter-heavy-chain disulphide bonds, in particular the bond at cys 337, are responsible for the limited susceptibility of F(ab)2 mu-like fragments to proteolysis.  相似文献   
18.
Female guinea pigs were treated daily with 1 mg of beta-estradiol-3-benzoate intramuscularly beginning 14 days before intravaginal inoculation with the chlamydial agent of guinea pig inclusion conjunctivitis and continuing during the course of the infection. Treatment with estradiol was found to markedly influence the course of genital infection with the chlamydial agent of guinea pig inclusion conjunctivitis, producing infections of greater intensity and longer duration than those in control animals. Moreover, pathogenesis was altered in that ascending infection was observed, resulting in endometritis, cystic salpingitis, and cystitis. Infection in the controls was limited to the cervix and vagina. Estradiol treatment increased the apparent number of infected cells in the cervix and vagina as detected by histopathology and immunofluorescent staining. Humoral and cell-mediated immune responses to the chlamydial agent of guinea pig inclusion conjunctivitis were comparable in estradiol-treated and untreated animals. These data indicate that hormonal manipulation may have profound effects on the course of chlamydial genital infections.  相似文献   
19.
With current trends in health consciousness, physicians are being asked to counsel individuals with chronic diseases who are involved in exercise programs. To accomplish this goal, health care providers should understand the effects of exercise on these individuals. Previously, epileptics were precluded from physical activity. Recent data reveals that exercise can be beneficial for epileptics. Therefore, in most cases, these individuals should be encouraged to participate in exercise programs. Asthmatics should be encouraged to participate in regular exercise to improve cardiovascular and respiratory fitness levels. For asthmatics, a proper exercise program can lead to an increased threshold before the stimulation of exercise-induced asthma occurs. The benefits of exercise for diabetics have been recognized for many decades. Exercise should be combined with appropriate diabetic education. Hypertrophic cardiomyopathy (HCM) is the number one cause of sudden death in young adults. HCM is a contraindication to strenuous exercise, but with proper medical management low-intensity exercise may be safely accomplished.  相似文献   
20.
OBJECTIVE: The study compared the demographic and diagnostic characteristics of clients and the outcomes of treatment in five short-term acute residential treatment programs and two acute hospital-based psychiatric programs. METHODS: A total of 368 clients in the short-term acute residential treatment programs and 186 clients in the psychiatric hospital programs participated in an observational study. The study used a repeated-measures design and assessed participants on multiple standardized measures of symptoms and functioning at admission, discharge, and four-month follow-up. Comparisons between the two groups were conducted separately by diagnostic category. Measures included the Brief Symptom Inventory, the Behavior and Symptom Identification Scale-32, the Medical Outcomes Short-Form-36, and the Client Satisfaction Questionnaire-8. RESULTS: The two types of programs admit persons with similar levels of acute distress who have comparable levels of improvement at discharge and an equivalent degree of short-term stability of treatment gains. Costs of treatment episodes were considerably lower for the short-term residential programs, and client satisfaction with the two types of programs was comparable. CONCLUSIONS: Short-term acute residential treatment is a less costly yet similarly effective alternative to psychiatric hospitalization for many voluntary adult patients.  相似文献   
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