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1.
Whole-body hyperthermia is the controlled elevation of systemic temperature for therapeutic purposes. Historically, this treatment has been used for symptomatic control of many diseases. Recently, the potential therapeutic benefit of whole-body hyperthermia in the management of neoplastic disease has been investigated vigorously. The rationale for improved tumor control is based on heat-induced enhancement of the antineoplastic effects of radiation and chemotherapy. Although the complex biologic interaction of heat and radiation has been studied for many years, chemotherapy combined with hyperthermia has been studied less thoroughly. Despite a lack of adequate long-term laboratory and clinical investigation, use of whole-body hyperthermia with chemotherapy and radiotherapy is a logical and potentially powerful therapeutic strategy for neoplasia. Relevant issues regarding the application of whole-body hyperthermia with more traditional modes of therapy are being studied in preliminary clinical trials involving dogs and humans. Identification of optimal timing and sequencing of adjunctive therapy, proper cytotoxic drug application, methods to further minimize toxicity, and heat-sensitive tumor types will lead to expanded clinical use of whole-body hyperthermia. The historical development, clinical rationale, and application of whole-body hyperthermia for the control of disseminated or refractory neoplasia in humans and dogs is reviewed.  相似文献   

2.
Twenty-two stages of the prenatal development of the domestic cat are described for intraspecies comparison in embryological studies. These are assigned to the 15 embryonal periods based on the Nomina Embryologica Veterinaria to make the interspecies comparison possible.  相似文献   

3.
Here we report the detection and distribution of synaptophysin (SPY), non-neuronal enolase (NNE), glial fibrillary acidic protein (GFAP), vimentin (VIM), neuropeptide Y (NPY), and vasoactive intestinal peptide (VIP) expression in the goat forestomach during prenatal development. A total of 140 embryos and fetuses were examined to evaluate protein expression from the first stage of prenatal life until birth. In all cases, SPY immunoreactivity was detected at 53 days gestation in the lamina propria-submucosa, tunica muscularis, serosa, and myenteric plexuses. Immunoreactivity to NNE was observed at 64 days gestation in the same locations as well as the epithelial layer. Glial cells were found at 64 days as indicated by signals corresponding to GFAP and VIM at 39 days. Positive staining for NPY and VIP was observed at 113, 75, and 95 days in the rumen, reticulum, and omasum, respectively, in the lamina propria-submucosa, tunica muscularis, and myenteric plexuses of each of these gastric compartments. These findings indicate possible preparation of the fetal goat forestomach for postnatal function. Compared to other ruminant species, neuroendocrine cells, glial cells and peptidergic innervations markers were detected earlier compared to sheep but at around the same stage as in deer.  相似文献   

4.
5.
The aim of this study was to perform a morphometric analysis of the different structural tissue layers of the goat stomach to study their prenatal growth from mathematical models fitted to these morphometric data. A total of 90 embryos and fetuses were used, from the early stages of prenatal life until birth. The growth rate of the gastric wall was slower than that of body length; rumen was the stomach compartment displaying slowest growth. In the three non‐glandular compartments, the epithelial layer grew faster than the gastric wall itself, while the growth rate of the abomasal epithelium declined in the early stages of development. A decline in growth rate was also observed for the lamina propria and submucosa in rumen and reticulum from the early embryonic stages, whereas in omasum and abomasum these layers continued to grow as gestation progressed. The tunica muscularis displayed consistent growth in all compartments, growing faster than the gastric wall. Serosa thickness increased as gestation progressed, displaying a decline in growth‐rate only in the omasum. In conclusion, the dynamics of gastric wall growth were governed by the growth rate of each of the component tissue layers.  相似文献   

6.
Described in this paper is the use of nootropics for stimulation of prenatal development of laboratory animals. Investigations, in that context, led to the discovery of so far unknown and unexpected properties of this group of medicaments. Foetal weight gain, reduction of teratogenicity, and decrease in implantation loss proved to be some of them.  相似文献   

7.
The appearance of haematopoietic cells and the development of haematopoiesis in certain embryonic organs of the cat were studied using light microscopic (cytological smears and paraffin embedded tissues) and transmission electron microscopic methods. Primitive erythropoiesis occurred predominantly in the yolk sac whereas definitive erythropoiesis occurred in the yolk sac, liver, bone marrow and, to a lesser extent, in the spleen. In the yolk sac, erythropoiesis was predominantly intravascular whereas in the liver and bone marrow it was usually extravascular. Granulopoiesis occurred mainly in the liver and bone marrow. In the liver it was predominantly extravascular and occurred around vessels, bile ducts and in perisinusoidal spaces. Megakaryocytopoiesis occurred in the yolk sac, liver, bone marrow and spleen. The megakaryocytic line of cells were similar to those occurring in adult cats except that in the yolk sac unusual small, mononuclear to binuclear thrombocytogenic megakaryocytes were present also. The relative contributions of the embryonic organs of the cat to haematopoiesis were similar to those described for man and certain other mammals but the results for the sites of development and the appearance of early forms in the erythrocytic, granulocytic and megakaryocytic lines varied at times from those reported for man and other mammals.  相似文献   

8.
The aim of this study is to describe differences in the ontogenesis of the abomasum in sheep (domestic ruminant) and deer (wild ruminant). Histomorphometric and immunohistochemical analysis were carried out on 50 embryos and fetuses of the sheep and 50 red deer from the first prenatal stages until birth. To compare similar periods of gestation in both species, we calculate the percentages of gestation. The appearance of the abomasum was earlier in the red deer (22% gestation) than in the sheep (25% gestation). Throughout development the epithelium happened sequentially, being of the types pseudostratified to simple cylindrical. This important modification was earlier in the red deer than the sheep. At 46% gestation in red deer and 50% in sheep, gastric pits were observed on the surface of abomasal folds. Our studies suggest a close link between the initial formation of these pseudoglandular structures and the clear separation of lamina propria and submucosa separated by de muscularis mucosae. At 54% gestation in red deer and at 60% in sheep, in the bottom of these pits the first outlines of glands were distinguishable. Finally, the presence of neuroendocrine and glial cells were detected in deer at earlier stages than in sheep.  相似文献   

9.
采用血清学试验对贵阳市花溪区某种猪场的95份血清样本进行猪繁殖障碍性疫病血清学检测,以了解猪群免疫水平及疫病感染状况.结果显示,猪群O型口蹄疫(O-FMD)、猪瘟(HC)、猪繁殖与呼吸障碍综合征(PRRS)、猪伪狂犬病(PR)免疫合格率分别为100% (33/33)、62.9%(39/62)、14.5% (9/62)、61.3% (38/62),HC、PRRS和PR免疫合格率均未达到农业部要求;通过比较母猪免疫抗体与仔猪母源抗体水平相关性,发现HC与PR首免后抗体保护期维持较短,PRRS免疫不合格;猪群猪圆环病毒病(PC)、猪细小病毒病(PP)隐性感染抗体阳性率分别为70.5% (67/95)、82.1%(78/95),隐性感染情况严重.血清流行病学调查结果表明,该猪场应改进HC、PR免疫程序,立即对全群进行PRRS补免,并要高度重视PC和PP的防控。  相似文献   

10.
On a broiler farm with a rearing capacity of about 200,000 chickens, a disease characterised by growth retardation, variability in chick size, 'leg weakness', diarrhoea and increased mortality at 3 weeks of age occurred repeatedly, in several successive broiler flocks. Gross and histopathological findings were dominated by widening of the hypertrophic and ossification layers of the physes of long bones as well as by thickening, unevenness and defective calcification of the cartilage trabeculae. In the parathyroid gland, vacuolar degeneration of the cytoplasm of glandular epithelial cells, connective tissue proliferation and, here and there, cyst formation were seen. Additional findings included severe cerebellar oedema and neuronal degeneration. The pancreatic, myocardial and intestinal changes typical of infectious stunting syndrome (ISS) occurred only in a mild form. Four-week-old chickens exhibiting 'leg weakness' had significantly lower blood inorganic phosphate concentration and tibial ash content as compared to healthy chickens. The disease was successfully transmitted by oral administration of small intestinal homogenate from affected chickens. In a second experiment, however, the disease could not be transmitted with intestinal homogenate sterilized by irradiation. Large doses of vitamin D3 reduced the rate of growth retardation and defective calcification of bones. The digestive enzyme activities of the pancreas and small intestinal mucosa of 'infected' chickens were decreased as is typical of ISS.  相似文献   

11.
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The prenatal development of the canine spinal cord was examined by light microscopy in 8 normal embryos and compared with the development of the spinal cord in 10 embryos obtained by mating severely dysraphic Weimaraner dogs. Dysraphic lesions were found in 80% of the embryos examined from dysraphic matings. The primary lesion was aberrantly positioned mantle cells ventrad to the central canal in the floor plate area. In 30% of the embryos of this group, there was a division of the terminal neural tube. The dysraphic embryos had significantly shorter gray matter and spinal cord transverse diameters. This confirmed the observation that the mantle cells in the dysraphic specimens were less differentiated, being more compact and appearing more basophilic when hematoxylin and eosin stains were used.  相似文献   

13.
14.
Fifty-one dogs bearing a variety of naturally occurring tumours were treated with combined radiation and hyperthermia. The treatment regime consisted of four, weekly fractions of radiation to a total dose of 3600–4000 cGys and one or two treatments with local microwave hyperthermia, heating the tumour to 44°C for 30 minutes on each occasion. Twenty-six (51 per cent) of the tumours showed a complete response to this treatment and a further eighteen (35 per cent) tumours underwent significant regression giving a total response rate of 86 per cent. Sixteen tumours later recurred at intervals of 11–50 weeks post treatment. The majority of tumours were in the oral cavity (35 cases) and in this group the survival rate compares favourably with figures for surgical treatment and radiotherapy alone. These findings support published results from other centres, indicating that hyperthermia combined with radiotherapy is a potentially useful technique for the management of certain canine malignant tumours.  相似文献   

15.
Aspects of placental protein and energy metabolism were examined in pregnant ewes subjected to either thermoneutral (TN, 18 to 20 degrees C, 30% humidity, n = 7) or hot (H, 30 to 40 degrees C, 40% humidity, n = 5) temperatures through mid and late gestation. Fetal and placental weights and total content of protein, RNA, and DNA were reduced (P less than .001) in H ewes. Placental protein and RNA concentrations (mg/g) were not different, and DNA concentrations were slightly greater (P less than .1), in H vs TN ewes. Thus, heat seemed to greatly reduce total cell number and placentome size and only slightly decrease cell size. Ratios of RNA to DNA indicated a reduced capacity for protein synthesis in H placenta. However, in vitro fractional rates of protein synthesis in tissue slices from the fetal and maternal placenta and from the myoendometrium were not different between TN and H ewes. The H ewes had greater placental protein concentrations of hydroxyproline and glycine, perhaps suggesting a greater collagen content. In vitro oxygen consumption of fetal placenta, but not of maternal placenta or myoendometrium, was lower in H than in TN ewes. This lower oxygen consumption was partially due to a lower Na+,K+ ATPase-dependent oxygen consumption.  相似文献   

16.
Summary In this study, the localization and appearance of synaptophysin-immunoreactive (IR) nerve cells and their relationships with the developing gastric layers were studied by immunocytochemistry and light microscopy in the embryonic rat stomach. The stomachs of Wistar rat embryos aged 13-21 days were used. The first neuronal bodies and their processes containing synaptophysin-immunoreactivity were observed on embryonic day 13. In contrast, synaptophysin-IR nerve terminals were first observed between mesenchymal cells on embryonic day 14. These results indicate that synaptophysin is expressed in growing neurits and neuronal cell bodies before these neurones have established synaptic connections. The occurrences of mesenchymal cell condensation near synaptophysin-IR neuroblasts on embryonic day 15 reflect an active nerve element-specific mesenchymal cell induction resulting in the morphogenesis of muscle cells. Similarly, the appearance of glandular structures after synaptophysin-IR neuroblasts, on embryonic day 18, suggests that the epithelial differentiation may be closely related to the neuronal maturation as well as other factors. Finally, synaptophysin is functionally important in neuronal development and maturation, together with the establishment of neuroneuronal and neuromuscular contacts and in epithelial differentiation.  相似文献   

17.
In mammals, the release from growth‐inhibiting conditions results in catch‐up growth. To investigate animal evidence for whether prenatal dexamethasone (DEX) treatment leads to the development of growth restriction especially reduced mineralization of skeleton, and release from it leads to the phenomenon of catch‐up, piglets were prenatally exposed to DEX (3.0 mg/sow per day?2) during the last 24 days of prenatal life and tested further in two different ways: discontinued at birth and continued administration of DEX (0.5 mg/kg day?2) to piglets through 30 days of neonatal life. Using dual energy X‐ray absorptiometry methods, bone mineral density (BMD) and bone mineral content (BMC) were measured. The three‐point bending test was applied to determine the mechanical properties of the bones. Furthermore, geometric properties of the bones were assessed. Serum concentration of osteocalcin (OC) was determined. Histomorphological analysis of the ribs was also performed. The consequences of neonate DEX treatment and in utero DEX exposure were reflected in a dramatic decrease of BMD, BMC and blood serum OC concentration and geometric parameters of piglets’ bones. Prenatal action of DEX during the last 24 days of pregnancy resulted in continued neonatal modification of bone tissues, thus diminishing bone quality, and negatively influenced structural development and mechanical properties, finally increasing the risk of fractures of ribs and limb bones. Prenatal DEX treatment limited to the last 24 days of foetal life did not reduce the term birth weight and the growth of suckling piglets followed up to 30 days of neonatal life, and catch‐up in bone mineralization did not occur.  相似文献   

18.
Thickness of epidermis, diameter and density of follicles as well as the ratio of secondary to primary follicles went up with significance (P less than 0.01) along with development. Medium concentrations of neutral and acid mucopolysaccharides were histochemically recorded from the corium, while high levels were present in basal stratum and hair pivots. High concentrations of alkaline phosphatase were recorded from basal stratum, hair pivots, and papillae and moderate concentrations from sweat and sebaceous glands, with the latter containing also glycogen and lipids.  相似文献   

19.
Seventy-one 10th-generation gilts from White Line-1 (WL-1 = randomly selected control line) and White Line-2 (WL-2 = selected for an index of ovulation rate and prenatal survival rate) were used to compare the pattern of follicular development and atresia during the follicular phase of the estrous cycle. Gilts were treated with PGF(2alpha)on d 13 of the estrous cycle (d 0 of induced follicular development) to induce luteolysis and assigned randomly within line and sire for ovary recovery on d 0, 2, 3, 4, 5, and the day after estrus. Ovaries were evaluated for numbers of corpora albicantia and small (2 to 2.9 mm), medium (M1 = 3 to 4.9 mm; M2 = 5 to 6.9 mm), and large (>or=7 mm) follicles. The concentration of estradiol-17beta in follicular fluid was used to classify individual M2 and large follicles as estrogen-active (>or=100 ng of estradiol-17beta/mL) or inactive (<100 ng of estradiol-17beta/mL). The WL-2 gilts had a greater ovulation rate than WL-1 gilts at their pre-treatment estrus (20.4 vs. 13.8 corpora albicantia; P < 0.001). The small and M1 follicle populations decreased rapidly in both lines over time (P < 0.001). The M2 follicle population increased in both lines between d 0 to 4 and then decreased. Mean estradiol concentration of M2 follicles increased in both genetic lines over time (P < 0.02). All large follicles were estrogen-active in both lines; the number of large follicles increased with day (P < 0.001) and was similar in both lines. The number of estrogen-active M2 follicles was similar in both lines, increasing to d 3 and 4 and then decreasing (P < 0.01) thereafter. However, the total number of estrogen-active follicles (sum of estrogen-active M2 and large follicles) was greater in WL-2 than in WL-1 gilts (P < 0.04), increasing to the ovulatory potential by d 3 in WL-1 gilts, but continuing to increase through d 4 in WL-2 gilts. Selection of an additional six ovulatory follicles from the estrogen-active M2 follicle pool after d 5 was required in both lines to achieve the projected ovulation rate, and after estrus, the number of large follicles remained insufficient to attain the ovulatory potential of each line.  相似文献   

20.
During pregnancy the developing embryo/foetus is completely dependent on the supply with nutrients and the removal of metabolic by-products through the maternal organism. Therefore, each lasting inadequate nutrient supply may have serious consequences for foetal development. As a kind of "nutritional programming" resulting adaptive changes may be maintained until or manifested at adult age. Intrauterine growth retardation (IUGR) may cause problems in animal health and result in poor animal performance. The relationships between prenatal development and the postnatal phenotypic appearance of muscle and fat are insufficiently investigated. The present paper provides selected aspects of the prenatal development of skeletal muscle (myogenesis) and adipose tissue (adipogenesis), refers to the importance of interactions between both tissues and is focussed on the influence of maternal nutrition on these processes.  相似文献   

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