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1.
J. W. K. Lien  L. R. Dufresne  D. S. Daly 《CMAJ》1974,110(11):1230-1231
A case of intramural esophageal hemorrhage in a hemodialysis patient is described. The hemorrhage followed an episode of vomiting and violent retching. Spontaneous resolution occurred with conservative management. The clinical course resembled that of previous case reports of intramural esophageal hemorrhage, whether or not associated with chronic renal failure and intermittent hemodialysis.  相似文献   

2.
During thrombolytic therapy and after recanalization is achieved, reduction in the volume of mural thrombi is desirable. Mural thrombi are known to contribute to rethrombosis and reocclusion. The lysis rate of mural thrombi has been demonstrated to increase with fluid flow in different experimental models, but the mechanisms responsible are unknown. An experimental and a theoretical study were developed to determine the contribution of outer convective transport to the lysis of mural fibrin clots. Normal human plasma containing recombinant tissue-type plasminogen activator (tPA; 0.5 microg/mL) was (re)perfused over mural fibrin clots with fluorescently labeled fibrin at low arterial, arterial, or higher wall shear stresses (4, 18, or 41 dyn/cm(2), respectively) and lysis was monitored in real time. Flow accelerated lysis, but significantly only at the highest shear stress: The average lysis front velocity was 3 x 10(-5) cm/s at 41 dyn/cm(2) vs. almost half of that at the lower shear stresses. Confocal microscopy showed fibrin fibers dissolving only in a narrow region close to the surface when permeation velocity was predicted to be low. A heterogeneous transport-reaction finite element model was used to describe mural fibrinolysis. After scaling the effects of outer and inner convection, inner diffusion, and chemical reactions, a simplified inner diffusion/reaction model was used. Correlation to fibrin lysis data in purified systems dictated higher rates of plasmin(ogen) and tPA adsorption onto fibrin and a decreased catalytic rate of plasmin-mediated fibrin degradation, compared with published parameters. At each shear stress, the model predicted a temporal pattern of lysis of mural fibrin (similar to that observed experimentally), and protease accumulation in a narrow fibrin region and significant lysis inhibition by plasma alpha(2)-antiplasmin (according to the literature). Increasing outer convection accelerated mural fibrinolysis, but the model did not predict the big increase in lysis rate at the highest shear stress. At higher than arterial flows, additional mechanisms not accounted for in the current model, such as fibrin collapse at the fibrin front, may regulate the lysis of mural clots and determine the outcome of thrombolytic therapy.  相似文献   

3.
This study explored the feasibility and clinical efficacy of expanded flap to repair facial scar left by radiotherapy of hemangioma. From March 2000 to April 2011, 13 cases of facial cicatrices left by radiotherapy of hemangioma have been treated with implantation surgery of facial skin dilator under local anesthesia. After water flood expansion for 1–2 months, resection of facial scar was performed, and wound repairing with expansion flap transfer was done. Thirteen patients were followed up from 5 months to 3 years. All patients tolerated flap transfer well; no contracture occurred during the facial expansion flap transfer. The incision scar was not obvious, and its color and texture were identical to surrounding skin. In conclusion, the use of expanded flap transfer to repair the facial scar left by radiotherapy of hemangioma is advantageous due to its simplicity, flexibility, and large area of repairing. This method does not affect the subsequent facial appearance.  相似文献   

4.
Immunoreactive neuropeptide Y (NPY) was demonstrated in neuronal elements in the urinary bladder wall of the newborn guinea pig. Numerous intramural ganglia were found lying among the smooth muscle bundles and in the submucosa, and NPY-like immunoreactive nerve cell bodies were demonstrated within all of these ganglia. Nerve fibres containing NPY were also richly distributed in the detrusor muscle, submucosa and around blood vessels. In dissociated cell cultures from newborn guinea pig detrusor muscle, a subpopulation (70-85%) of both mononucleate and binucleate intramural neurones was shown to contain NPY-like immunoreactivity. A low percentage (1-6%) of the intramural bladder neurones contained dopamine-beta-hydroxylase. In conclusion, while some NPY-containing nerve fibres in the wall of the bladder are of sympathetic origin, especially those supplying blood vessels, the results of this present study establish that many of these NPY-containing nerve fibres originate from non-adrenergic cell bodies within the intramural bladder ganglia.  相似文献   

5.
Concomitant nasal zygomycosis and pulmonary aspergillosis was diagnosed in a 3-mo-old female American bison calf (Bison bison) in Pennsylvania (USA). Etiologic diagnosis was made by immunohistochemistry using a panel of monoclonal antibodies and heterologously absorbed polyclonal antibodies. In the lungs fungal infection was accompanied by hemorrhage, fibrin exudation, and infiltration with neutrophils. Fungi were observed to penetrate apparently normal epithelial lining of the nasal turbinates, and there was hemorrhage, edema, and invasion of blood vessels in the submucosa. In vessels fungi were typically associated with thrombosis. The calf may have been infected due to a high level of exposure to mouldy feed and litter in the environment in combination with a collapse of it's natural defence mechanisms.  相似文献   

6.
Evaluation of fibrin glue in rat sciatic nerve repairs   总被引:2,自引:0,他引:2  
Using the rat sciatic nerve model, we evaluated the merits of homologous fibrin glue in the repair of peripheral nerve transections as compared to standard epineural suture repairs. A total of four study groups were used, with 10 animals assigned to each group. In group I, the transected sciatic nerve was repaired with six interrupted 10-0 nylon sutures; in group II, only two interrupted sutures were used; in group III, a two-suture repair was reinforced with fibrin glue; and in group IV, only fibrin glue was used. All animals were sacrificed at 8 weeks, and histologic sections evaluated. When fibrin alone was used, dehiscence occurred in 80 percent of the animals, and as reinforcement of a two-suture repair, it only increased the inflammatory reaction.  相似文献   

7.
Histopathologic interpretation of dermoscopic and reflectance confocal microscopy (RCM) features of cutaneous melanoma was timidly carried out using perpendicular histologic sections, which does not mimic the same plane of the image achieved at both techniques (horizontal plane). The aim of this study was to describe the transverse histologic sections research technique and correlate main dermoscopic features characteristic of cutaneous melanoma (atypical network, irregular globules and pseudopods) with RCM and histopathology in perpendicular and transverse sections in order to offer a more precise interpretation of in vivo detectable features. Four melanomas and 2 nevi with different dermoscopic clues have been studied. Lesion areas that showed characteristic dermoscopic features were imaged by dermoscopy and confocal microscopy and directly correlated with histopathology in perpendicular and transverse sections. We presented the possibility to perform transverse sections as a new approach to understand RCM features. Atypical network showed different aspects in the 2 melanomas: in one case it was characterized by pleomorphic malignant melanocytes with tendency to form aggregates, whereas in the other elongated dendritic cells crowded around dermal papillae, some of them forming bridges that resembled the mitochondrial aspect at confocal and histopathology transversal sections. Pigment globules in melanomas and nevi differed for the presence of large atypical cells in the former, and pseudopods showed up as elongated nests protruded toward the periphery of the lesion. Transverse histologic research sections have a consistent dermoscopic and confocal correlate, and it may represent an help in confocal feature interpretation and an advance in improving melanoma diagnosis and knowledge of the biology of melanocytic lesions.  相似文献   

8.
贵州省城镇建设用地扩展的时空演变特征   总被引:1,自引:0,他引:1  
选择贵州省的85个城镇为研究区,运用1973年1∶5万地形图,1986、1995、2000和2007年4期高分辨率遥感影像,选取城镇扩展动态度指数、城镇扩展贡献率指数和城镇扩展强度指数3个指标,构建城镇综合扩展程度指数模型,定量分析了1973—2007年4个时期贵州省城镇建设用地扩展的总体特征和时空分异特征。结果表明:从1973—2007年,贵州省城镇建设用地呈持续增长态势,城镇建设用地面积共增加17550.8915hm2,其中2000—2007年贵州省城镇建设用地扩展面积最大,动态度、贡献率和强度指数均最大;研究区建设用地扩展具有明显的空间分异特征,1973—1986年,城镇建设用地扩展主要集中在省会城市贵阳市,1986—1995年,地级城市所在城镇扩展面积和强度快速提高,1995—2000年,交通沿线城镇扩展速度加快,2000—2007年,贵州省城镇扩展强度和综合扩展程度不仅在贵阳市和地级城市较快,而且在区位和自然条件良好的县级城镇也迅速提高。  相似文献   

9.
Mural and cumulus granulosa cells synthesize hyaluronic acid (HA) and expand in vitro in response to follicle-stimulating hormone and a soluble factor(s) produced by fully grown oocytes. In the present study we examined HA synthesis and extracellular matrix organization by the two cell populations in vivo during the preovulatory period. After injection of human chorionic gonadotropin into pregnant mares' serum gonadotropin-primed animals, a progressive increase in HA synthesis was observed by the cumulus cell-oocyte complex (COC), and by the mural granulosa cells adjacent to the antrum (antral granulosa cells). The outermost layers of mural granulosa cells (peripheral granulosa cells) did not synthesize HA. Net HA synthesis was approximately 4 pg/cell for COCs isolated after full expansion induced either in vivo or in vitro, whereas the total HA content and cell number in the ovulated COC (approximately 11 ng HA and approximately 3000 cells per COC) were about threefold higher than for COCs expanded in vitro (approximately 4 ng HA and approximately 1000 cells per COC). The increased cell content of ovulated COCs appears to be primarily the result of inclusion of proximal mural granulosa cells which synthesize HA in response to the oocyte factor(s) and become incorporated in the expanded COC extracellular matrix mass. Media conditioned by oocytes enclosed in the cumulus cell mass (intact COCs) contained only 10-20% of the HA-stimulatory activity of media conditioned by an equal number of isolated oocytes when tested on mural granulosa cell cultures. Further, HA-stimulatory activity of media conditioned by isolated oocytes was dramatically reduced (approximately 70%) by preincubation for 5 hr with cumulus cells compared to preincubation in the absence of cells. The results suggest that differences in HA synthesis between subregions of membrana granulosa depend on a diffusion gradient of the oocyte factor(s).  相似文献   

10.
To obtain information about changes that occur in hair follicles when tissue expansion is performed on the scalp, punch biopsy samples were taken from normal scalp (stage I) and the top of the expander immediately before removal (stage II) and 12 weeks after the second operation (expander removal and flap transposition, stage III) in 10 consecutive patients. We compared histologic and quantitative changes of hair follicles in transverse sections of the expanded scalp and long-term changes with those in normal controls using three specimens from each patient. Both the proportion of terminal hair to vellus hair and the proportion of anagen hair to telogen hair were significantly increased during stages II and III (p < 0.05). Perifollicular inflammation and fibrosis were observed during stage II but disappeared during stage III. All these findings imply that tissue expansion at the hair-bearing scalp made the telogen period short, possibly because of active epidermal mitosis.  相似文献   

11.
This study was undertaken to differentiate between the morphological changes produced in chambered rat gastric mucosae by 40% ethanol and by 50 mM HCl. 40% ethanol produced both focal mucosal hyperemia and widespread exfoliation of the surface epithelium. Massive release of mucus accompanied both events. In the absence of acid the released mucus was stabilized by a network of fibrin, and epithelial continuity was re-established over non-hyperemic regions by migration of epithelial (and parietal) cells from the gastric pits. Hemorrhagic erosions occurred only in the presence of acid, but were limited to the hyperemic regions. Acid had the following effects: (1) platelet thrombi were destroyed, thus promoting hemorrhage; (2) destruction of the fibrin network by acid caused dissipation of the adherent mucous coat; (3) vulnerable cells which had previously shown only ischemic damage were irreversibly damaged by acid; (4) exposed basal lamina was destroyed, thus removing the substratum necessary for orderly epithelial re-establishment.  相似文献   

12.
The inbuilt intrinsic cholinergic nervous apparatus of the gastric wall of the cat was studied by using two thiocholine methods for mapping the acetylcholinesterase-positive nerves and nerve cells. A rich distribution of acetylcholinesterase-positive nerves was observed in all layers of the gastric wall, except the superficial half of the lamina propria (with the epithelium), which was completely devoid of acetylcholinesterase activity, and the submucosa, in which a scarce distribution of large nerve fascicles and nerve trunks was observed. Acetylcholinesterase-positive ganglia were observed both in the subserous layer and in the myenteric plexus of Auerbach, whereas none were recognized in the submucous plexus of Meissner. This obviously fits well to the results of some electrophysiological experiments which indicate that the submucous plexus of Meissner includes an important intramural pathway from the extrinsic vagus nerves to the antrum region; so the submucous plexus of Meissner seems to be mainly involved in direct rapid conduction of nerve impulses without integrative activities, like a cable. Certain clear differences exist in the pattern of organization of the cholinergic intrinsic nervous apparatus within the different layers of the gastric wall in the fundic and pyloric regions. These differences seem to correspond quite logically to the different types of motor, secretory and neurohumoral activities of these main regions of the stomach. The activity of the non-specific cholinesterases was localized both in the neural elements and the smooth muscle, as well as in some epithelial cells.  相似文献   

13.
 Bladder-washing-derived lymphocytes (BWDL) from 67 patients with bladder cancer were studied. The large majority of samples contained a pure population of T lymphocytes, whereas B and NK cells were absent. A comparative analysis of bladder lymphocytes and peripheral blood lymphocytes (PBL), collected in parallel, showed that BWDL significantly differed from PBL. In vitro cultures of bladder lymphocytes were attempted on 21 samples but in vitro expansion was only possible on six patients treated with bacillus Calmette-Guérin (BCG). This finding indicates that BWDL are characterized by a severe proliferative defect. Nevertheless, the addition of BCG on bladder lymphocytes expanded in vitro enhanced their proliferation, suggesting that this population is sensitized against BCG antigen(s). The analysis of T cell receptor restriction patterns showed that bladder lymphocytes from patients under BCG treatment were oligoclonal. A possible explanation for the efficiency of the immune response and good clinical outcome in patients treated with BCG could be found in the high homology between some BCG antigens and human heat-shock proteins, which are overexpressed in transformed cells. Received: 8 June 1995 / Accepted: 22 November 1995  相似文献   

14.
A male northern elephant seal (Mirounga angustirostris) that was conceived in captivity was stillborn February 14, 1981, at Mystic Marinelife Aquarium in Mystic, Connecticut. Either of two males in the exhibit could have sired the pup. Both were only 3 yr at the time of conception.  相似文献   

15.
Isolated frog nerves or rabbit sinus node strips were mounted in a single sucrose gap chamber. A fibrin glue Tissucol was used in this arrangement as an intercompartment seal. Under such conditions, the specimens produced stable trans-gap action potentials of relatively high amplitude. In other experiments the gap was filled with fibrin in place of sucrose solution. The results obtained in the fibrin gap experiments resembled these mentioned above.  相似文献   

16.
Tendon defects remain a major concern in plastic surgery because of the limited availability of tendon autografts. Whereas immune rejection prohibits the use of tendon allografts, most prosthetic replacements also fail to achieve a satisfactory long-term result of tendon repair. The tissue engineering technique, however, can generate different tissues using autologous cells and thus may provide an optimal approach to address this concern. The purpose of this study was to test the feasibility of engineering tendon tissues with autologous tenocytes to bridge a tendon defect in either a tendon sheath open model or a partial open model in the hen. In a total of 40 Leghorn hens, flexor tendons were harvested from the left feet and were digested with 0.25% type II collagenase. The isolated tenocytes were expanded in vitro and mixed with unwoven polyglycolic acid fibers to form a cell-scaffold construct in the shape of a tendon. The constructs were wrapped with intestinal submucosa and then cultured in Dulbecco's Modified Eagle Medium plus 10% fetal bovine serum for 1 week before in vivo transplantation. On the feet, a defect of 3 to 4 cm was created at the second flexor digitorum profundus tendon by resecting a tendon fragment. The defects were bridged either with a cell-scaffold construct in the experimental group ( n= 20) or with scaffold material alone in the control group ( n= 20). Specimens were harvested at 8, 12, and 14 weeks postrepair for gross and histologic examination and for biomechanical analysis. In the experimental group, a cordlike tissue bridging the tendon defect was formed at 8 weeks postrepair. At 14 weeks, the engineered tendons resembled the natural tendons grossly in both color and texture. Histologic examination at 8 weeks showed that the neo-tendon contained abundant tenocytes and collagen; most collagen bundles were randomly arranged. The undegraded polyglycolic acid fibers surrounded by inflammatory cells were also observed. At 12 weeks, tenocytes and collagen fibers became longitudinally aligned, with good interface healing to normal tendon. At 14 weeks, the engineered tendons displayed a typical tendon structure hardly distinguishable from that of normal tendons. Biomechanical analysis demonstrated increased breaking strength of the engineered tendons with time, which reached 83 percent of normal tendon strength at 14 weeks. In the control group, polyglycolic acid constructs were mostly degraded at 8 weeks and disappeared at 14 weeks. However, the breaking strength of the scaffold materials accounted for only 9 percent of normal tendon strength. The results of this study indicated that tendon tissue could be engineered in vivo to bridge a tendon defect. The engineered tendons resembled natural tendons not only in gross appearance and histologic structure but also in biomechanical properties.  相似文献   

17.
Dermal and epidermal response to soft-tissue expansion in the pig   总被引:10,自引:0,他引:10  
To evaluate the dermal and epidermal response to soft-tissue expansion in the pig, round tissue expanders were placed dorsally under tattooed patterns and inflated over 6 weeks. Surface area, skin thickness, histologic changes, and collagen content were evaluated at 6-week intervals. Epidermal thickening and dermal thinning were observed. Dermal thinning persisted 36 weeks after expansion. Dermal collagen content was decreased, although collagen density remained unchanged. Total collagen content calculated within an expanded square grid increased. These data support a theoretical gain in the dermal layer as well as epidermal layer in response to tissue expansion.  相似文献   

18.
A new mutant strain of inbred Sprague Dawley rats with autosomal recessive hyperbilirubinuria, were studied by biochemical, histologic, and ultrastructural methods. The plasma bilirubin concentration in the homozygote was significantly higher than that of the heterozygote, and about 80% of the bilirubin was conjugated. Plasma BSP and ICG clearance were both severely delayed in the homozygote. Plasma BSP elimination kinetics suggested that the pathophysiologic defect was not hepatic uptake or storage but rather in secretion into bile. Histopathology of the liver demonstrated brown pigment in the hepatocytes that appeared to be lipofuscin. The electron microscopic features of the hepatic pigment resembled those of the Dubin-Johnson syndrome. Homozygote histopathology also revealed glomerular lesions with mesangial expansion and proliferation in the kidneys. Immunohistologic studies disclosed mesangial granular deposition of IgG, IgA, and to a lesser degree, IgM and C3. These renal changes resembled those of IgA nephropathy. The spontaneous hyperbilirubinuric rat (EHBR) may be a useful animal model for studying constitutive conjugated hyperbilirubinemia, bilirubin metabolism, cholestasis, and glomerulonephropathy subsequent to hepatic dysfunction.  相似文献   

19.
Formation of gastric mucosal lesions by streptozotocin-induced diabetes was investigated in rats. A single intravenous administration of streptozotocin in a dose of 65 mg/kg effectively produced hyperglycemia and damaged the gastric mucosa. Incidence and severity of mucosal lesions were progressively increased with time, from one to six weeks posttreatment. Microscopic lesions of the mucosa included hyperemia, desquamation of the surface epithelium with diffuse hemorrhage, and severe hemorrhage with localized erosion. Concurrent to the hyperglycemia, the histamine stimulated gastric H+-secretion was significantly decreased whereas pepsin secretion was not affected. Both soluble mucus and surface mucus gel were increased. The result suggests that the early lesion of gastric mucosa may be associated with the direct action of streptozotocin, the severity of which may be further aggravated by diabetic state.  相似文献   

20.
Cavernous hemangioma consists mainly of congenital vascular malformations present before birth and gradually increasing in size with skeletal growth. A small number of patients with cavernous hemangioma develop scoliosis, and surgical treatment for the scoliosis in such cases has not been reported to date. Here we report a 12-year-old male patient with severe progressive scoliosis due to a huge subcutaneous cavernous hemangioma, who underwent posterior correction and fusion surgery. Upon referral to our department, radiographs revealed a scoliosis of 85° at T6-L1 and a kyphosis of 58° at T4-T10. CT and MR images revealed a huge hemangioma extending from the subcutaneous region to the paraspinal muscles and the retroperitoneal space and invading the spinal canal. Posterior correction and fusion surgery using pedicle screws between T2 and L3 were performed. Massive hemorrhage from the hemangioma occurred during the surgery, with intraoperative blood loss reaching 2800 ml. The scoliosis was corrected to 59°, and the kyphosis to 45° after surgery. Seven hours after surgery, the patient suffered from hypovolemic shock and disseminated intravascular coagulation due to postoperative hemorrhage from the hemangioma. The patient developed sensory and conduction aphasia caused by cerebral hypoxia during the shock on the day of the surgery. At present, two years after the surgery, although the patient has completely recovered from the aphasia. This case illustrates that, in correction surgery for scoliosis due to huge subcutaneous cavernous hemangioma, intraoperative and postoperative intensive care for hemodynamics should be performed, since massive hemorrhage can occur during the postoperative period as well as the intraoperative period.  相似文献   

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