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1.
The morphology of the basilar papilla of the emu was investigated quantitatively with light and scanning electron microscopical techniques. The emu is a member of the Paleognathae, a group of flightless birds that represent the most primitive living avian species. The comparison of the emu papilla with that of other, more advanced birds provides insights into the evolution of the avian papilla. The morphology of the emu papilla is that of an unspecialised bird, but shows the full range of features previously shown to be typical for the avian basilar papilla. For example, the orientation of the hair cells' sensitive axes varied in characteristic fashion both along and across the papilla. Many of the quantitative details correlate well with the representation of predominantly low frequencies along the papilla. The most distinctive features were an unusually high density of hair cells and an unusual tallness of the hair-cell bodies. This suggests that the evolution of morphologically very short hair cells, which are a hallmark of avian papillae, is a recent development in evolution. The small degree of differentiation in hair-cell size contrasts with the observation that a significant number of hair cells in the emu lack afferent innervation. It is therefore suggested that the development of functionally different hair-cell types in birds preceded the differentiation into morphologically tall and short hair cells.  相似文献   

2.
Calcium and magnesium levels in the cortex, medulla, and papilla of human kidney from 32 so-called healthy patients and from eleven patients with calcium-oxalate lithiasis were determined by atom-absorption spectralphotometry. A positive calcium gradient with the highest calcium concentration in the papilla was found in all kidneys. Compared to the control group, that calcium concentration in the lithiasic kidneys was reduced by 50% in the papilla, but in the cortex and medulla, the levels were the same. A relative depletion of calcium in the papilla in hypercalciuria goes against the theory that the papilla is the main center of development of calcium-containing stones. The magnesium concentration was practically the same in cortex, medulla, and papilla, and no significant difference was found between lithiasic and healthy kidneys. These findings underline the central role of calcium in the genesis of calcium-containing stones.  相似文献   

3.
Hair cells in the basilar papilla of birds have the capacity to regenerate after injury. Methods commonly used to induce cochlear damage are systemic application of ototoxic substances such as aminoglycoside antibiotics or loud sound. Both methods have disadvantages. The systemic application of antibiotics results in damage restricted to the basal 50% of the papilla and has severe side effects on the kidneys. Loud sound damages only small parts of the papilla and is restricted to the short hair cells. The present study was undertaken to determine the effect of local aminoglycoside application on the physiology and morphology of the avian basilar papilla. Collagen sponges loaded with gentamicin were placed at the round window of the cochlea in adult pigeons. The time course of hearing thresholds was determined from auditory brain stem responses elicited with pure tone bursts within a frequency range of 0.35-5.565 kHz. The condition of the basilar papilla was determined from scanning electron micrographs. Five days after application of the collagen sponges loaded with gentamicin severe hearing loss, except for the lowest frequency tested, was observed. Only at the apical 20% of the basilar papilla hair cells were left intact, all other hair cells were missing or damaged. At all frequencies there was little functional recovery until day 13 after implantation. At frequencies above 1 kHz functional recovery occurred at a rate of up to 4 dB/day until day 21, beyond that day recovery continued at a rate below 1 dB/day until day 48 at the 5.6 kHz. Below 1 kHz recovery occurred up to day 22, the recovery rate was below 2 dB/day. A residual hearing loss of about 15-25 dB remained at all frequencies, except for the lowest frequency tested. At day 20 new hair cells were seen on the basilar papilla. At day 48 the hair cells appeared to have recovered fully, except for the orientation of the hair cell bundles. The advantage of the local application of the aminoglycoside drug over systemic application is that it damages almost all hair cells in the basilar papilla and it has no toxic side effects. The damage is more extensive than with systemic application.  相似文献   

4.
In the adult hair follicle the dermal papilla plays a crucial role in the dermal-epidermal interactions that control hair production and events of the growth cycle. It has previously been shown that cultured cells from rat vibrissa follicle dermal papillae can stimulate hair growth when implanted into amputated follicles. This study investigated the effects of implanting low-passage cultured papilla cells into small incisional wounds in the rat ear pinna. The groups of fibers that emerged from wound sites were much larger than local hairs, and often had vibrissa-type characteristics. Later-passage papilla cells or cultured skin fibroblasts failed to elicit the same response. Histology revealed that big follicles were formed when papilla cells were trapped between the cut edges of the epidermis. Abnormally large follicles were seen at wound sites many months post-operatively. Independent of epidermal influence, cultured papilla cells in the wound dermis formed rounded papilla-like aggregates that also persisted until biopsy. A previously described method of wrapping papilla cells in glabrous epidermis was less successful in percentage terms but resulted in the production of one very large vibrissa-type follicle and fiber. These results further illustrate that the inductive powers and developmental information retained by cultured dermal papilla cells parallel the properties of their embryonic precursors; the findings may have implications for human hair growth.  相似文献   

5.
BACKGROUND: Our aims were to investigate the question as to whether the adenoma-carcinoma sequence also applies to the papilla of Vater and to determine the frequency with which a tumour of the papilla of Vater, diagnosed histologically as containing portions of an adenoma, already contains adenocarcinoma elsewhere. METHODS: A retrospective analysis was carried out of the forceps, snare biopsy, and excised specimens obtained from the papilla of Vater in 559 patients, including 210 patients with the primary diagnosis of carcinoma and 110 patients with the diagnosis of 'portions of an adenoma'. Comparisons were made of the age distribution of patients with adenoma and those with carcinoma, and the frequency of residual adenoma in a carcinoma as a function of degree of malignancy, T stage, and UICC stage. A follow-up examination of the patients with the primary diagnosis 'parts of an adenoma of the papilla of Vater' was performed. RESULTS: The average age of the patients with the final diagnosis adenoma was 65.2 years, and that of the carcinoma patients 73.0 years. Residual adenoma was found in 54.9% of the 51 surgical specimens and in 31.7% of the 159 biopsy specimens obtained from carcinomas. The frequency of residual adenoma in carcinomas decreased statistically significantly with increasing T stage and degree of malignancy. The follow-up examination of the 110 patients with the primary biopsy diagnosis parts of an adenoma of the papilla of Vater showed unequivocal results in 80 cases. Only in 39.7% of these cases was the primary diagnosis adenoma confirmed, whereas in 60.25%, further histologic examination showed a carcinoma. CONCLUSIONS: An analysis of our results, together with those reported in the literature, indicates that the adenoma-carcinoma sequence also applies to the papilla of Vater and that, in a high percentage of patients with the histologic diagnosis 'parts of an adenoma, other regions of the tumour already contain a carcinoma.  相似文献   

6.
In a clinical-experimental study the influence of variations in the palatal shape of upper removable appliances upon tongue position during swallowing was investigated. During a clinical examination of 35 dental students displaying a physiological swallowing pattern, the tongue position during swallowing was recorded by palatography on an individually adapted upper plate. During swallowing with a roughened plate with an individual palatal shape and an imitated palatal papilla, the tongue position was significantly more posterior than with a highly polished, unstructured plate. The number of students displaying a visceral swallowing pattern was significantly smaller with a roughened plate with palatal folds and papilla then with a polished, smooth appliance. A roughened, individually shaped appliance with palatal folds and palatal papilla should therefore be used after myofunctional therapy and in cases where disturbance of tongue function by the appliance is not desirable.  相似文献   

7.
Dermal papilla cells of rat vibrissa follicles cultivated in monolayers and in three-dimensional collagen gels show a different morphology in these culture systems. Dermal papilla cells cultured in lattices tend to express morphological features resembling those seen in vivo. Quantification of total collagen by incorporation of 3H-proline in monolayer cultures and in collagen lattices show that the amount of collagen found in dermal papilla cells is higher than that secreted. Moreover, collagen synthesis measured in lattices is reduced to about 50% of that found in monolayer cultures. The influence of growth factors on collagen synthesis by hair dermal papilla cells was investigated. We studied the effects of basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF) and minoxidil on collagen synthesis in monolayers and in lattices. VEGF, bFGF and minoxidil significantly decreased the total amount of collagen. In monolayer cultures, there was approximately a 30% inhibition of collagen production with 5 ng/ml bFGF, 0.1 ng/ml VEGF and 100 ng/ml minoxidil. However, in the lattices this inhibition was reduced to about half. These results suggest that both culture substrate and growth factors influence collagen production by rat hair dermal papilla cells.  相似文献   

8.
In histochemical studies it was shown that sulfated acid glycosaminoglycans (AGAGS) were produced and secreted into the tubular lumen in renal papilla, but not in the renal cortex of muddy stone forming kidney. There was no secretion of sulfated AGAGS in renal papilla histochemically during hydronephrosis before stone formation. On autoradiographic study with the use of 45Ca and 35S for labeling of sulfated AGAGS, we found that 45Ca accumulated in renal papilla of muddy stone forming kidney, but not in the other. 35S apparently accumulated into muddy stones. Measurement of calcium content of the renal papilla and cortex proved the results of autoradiographic studies, and measurement of uronic acid in the urine showed increased secretion of AGAGS in the urine from muddy stone forming kidney. From these results it was proposed that the sulfate AGAGS secreted in the urine could bind calcium crystals to each other amd make crystals aggregate massively.  相似文献   

9.
Pancreas divisum patients make up a small but problematic portion of ERCP cases. Minor papilla cannulation techniques have been improved. Recurrent pancreatitis patients generally benefit from minor papilla therapy. Methods to select patients who are likely to respond to invasive therapy need refinement. Clinicians and endoscopists are strongly encouraged to be cautious and conservative with this patient group until stronger data indicate optimal management schemes.  相似文献   

10.
Ionic currents are critical for the functioning of the inner ear auditory sensory epithelium. We set out to identify and molecularly clone the genes encoding the channels responsible for several currents in the chick basilar papilla. Here we describe an inward-rectifying K+ channel, cKir2.3, present in both hair cells and support cells in the apical end of the chick basilar papilla. The biophysical properties of the human ortholog, hKir2.3, are similar to those of an inward-rectifying channel found in the apical end of the chick basilar papilla, suggesting that this channel may contribute to the corresponding current. Additionally, we describe two new members of the Kv6 subfamily of putative regulatory voltage-gated K channels, cKv6.2 and cKv6.3. Both are expressed in hair cells in the apical end of the chick basilar papilla; cKv6.2 is also strongly expressed in support cells and in the brain.  相似文献   

11.
The technique spontaneously or siphoned after cholecystokinin stimulation. Our technique of cell collection within the region of the duodenum, the pancreas and the bile-ducts have been optimal performed by duodenoscopical methods. From the papilla of Vater, the cell brush abrasion is used. Pancreatic secretions are obtained by praepapillary drainage with a catheter after secretin stimulation or siphoned after canulation of the ductus Wirsungianus. Bile is obtained wth the same technique of material collection and processing is described. Characteristical tumor cell findings of the papilla of Vater, of the pancreas and the bile ducts are demonstrated and the cytodiagnostic's position within the tumor recognition in this area is discussed. We think the tumor cell search with the described duodenoscopical techniques as indicated in following cases: 1. suspicion of carcinoma of papilla of Vater, 2.obstructve jaundice, 3. in search of carcinoma of the pancreas.  相似文献   

12.
In a unilateral ureteral obstruction model, a progressive accumulation of hyaluronan (HA) was observed in the renal papilla during the first 11 days of obstruction, after which the amount of HA decreased until the last day of observation, i.e. day 22. The initial accumulation of HA in the obstructed kidney probably reflects the attempts of the kidney to maintain osmotic balance. Consequently, when filtration ceases, HA synthesis decreases and the concentration of HA falls. In the papilla of the contralateral kidney, that had not been exposed to any mechanical damage, the HA content was found to vary in a similar way to that in the obstructed kidney. The explanation for this could be that the mesenchymal cells within the papilla increase their production of HA in order to meet the requirements of increased function necessary to also shoulder the function of the damaged kidney. In short similar variations in the HA content of the renal papilla was observed in both healthy and obstructed kidneys in a unilateral ureteral obstruction model.  相似文献   

13.
Pancreas divisum, partial or nonfusion of the dorsal and ventral pancreatic ductal systems, affects up to 10 per cent of the population. Approximately 25 per cent of patients with pancreas divisum will develop complications such as recurrent pancreatitis as a consequence of stenosis of the minor papilla with altered dorsal duct drainage. Surgical and endoscopic therapy usually include minor papilla sphincterotomy or sphincteroplasty to facilitate drainage of the dorsal ductal system. The following case represents an unusual complication of pancreas divisum with primarily ventral duct disease and pancreaticolithiasis.  相似文献   

14.
The blood supply in the equine hoof was studied by a microvascular casting corrosion technique and scanning electron microscopy in combination with observations of sections of the decalcificated digit. The dermal lamella was observed at the hoof wall and the dermal papilla at the other parts of the hoof. The microvascular architecture of the dermal lamella differed from that of dermal papilla. The vascular cast in the dermal papillar regions indicated that each papilla contained two central vessels (artery and vein), which ran parallel to each other, and the capillary plexus surrounding these vessels. In the dermal lamella region, the vessels consisted of thin parallel sheets arranged in vertical rows. Each sheet was made of branched arteries and veins, both of which were sandwiched between capillary plexus. At the distal and proximal parts of the wall, the vascular casts of the papillae merged to form the vascular sheets of the dermal lamella.  相似文献   

15.
A 57 year-old Japanese man with a carcinoid somatostatinoma of the papilla of Vater is presented. He was found to have cholecystolithiasis without any symptoms. Physical examination showed no abnormal findings. Routine laboratory data gave normal results, except for glucose intolerance and an elevated somatostatin concentration. A yellowish papillary tumor was found at the papilla of Vater, and histological examination suggested the diagnosis of carcinoid. He underwent a pancreatoduodenectomy in March 1992. The gallbladder contained a single pure cholesterol stone. Histological, immunohistochemical, and electron microscopic studies resulted in the diagnosis of a carcinoid somatostatinoma of the papilla of Vater, without regional lymph node metastases. Post-operative pancreatic juice output from the total pancreatic duct drainage increased to more than 1000 mL/day. Although an anastomotic leakage of the pancreatojejunostomy was noted, the pancreatic fistula closed 8 weeks later. His postoperative somatostatin value was normal. He has been well for 54 months following surgery, without any signs of recurrence.  相似文献   

16.
A 71-year-old man with a tumorous lesion of the common bile duct is presented. Although histological examination of tumor biopsy specimens taken at the time of duodenoscopy or percutaneous transhepatic choledochoscopy showed mucosal hyperplasia, cancer could not be ruled out; therefore, the patient underwent pancreatoduodenectomy. However, histology showed nodular mucosal hyperplasia and an ectopic pancreas adjacent to the papilla of Vater, which was suspected to have contributed to the development of the lesion by stimulating the mucosa of the papilla and the distal common bile duct.  相似文献   

17.
Male Bengalese finches do not normally change their vocal patterns in adulthood; song is stereotyped and stable over time. Adult song maintenance requires auditory feedback. If adults are deafened, song will degrade within 1 week. We tested whether feedback of all sound frequencies is required for song maintenance. The avian basilar papilla is tonotopically organized; hair cells in the basal region encode high frequencies, and low frequencies are encoded in progressively apical regions. We restricted the spectral range of feedback available to a bird by killing either auditory hair cells encoding higher frequencies or those encoding both high and low frequencies and documented resultant changes in song. Birds were treated with either Amikacin alone to kill high-frequency hair cells or Amikacin and sound exposure to target hair cells across the entire papilla. During treatment, song was recorded from all birds weekly. After treatment and song recording, evoked-potential audiograms were evaluated on each bird, and papillas were evaluated by scanning electron microscopy. Results showed that hair cell damage over 46-63% of the basal papilla and the corresponding high-frequency hearing loss had no effect on song structure. In birds with hair cell damage extending further into the apical region of the papilla and corresponding low-frequency and high-frequency hearing loss, song degradation occurred within 1 week of beginning treatment and was comparable with degradation after surgical deafening. We conclude that either low-frequency spectral cues or temporal cues via feedback of the song amplitude envelope are sufficient for song maintenance in adult Bengalese finches.  相似文献   

18.
BACKGROUND/AIMS: Endoscopic sphincterotomy for common bile duct stone clearance during laparoscopic cholecystectomy may fail due to difficulties in cannulating the papilla major. In this study we propose a new technique that facilitates the cannulation of the papilla and the common bile duct stone clearance during a standard laparoscopic cholecystectomy. Its clearance percentage, complication rate and post-operative stay have been evaluated and compared with standardized procedures such as open surgery and endoscopic sphincterotomy before laparoscopic cholecystectomy. METHODOLOGY: In a group of 16 patients presenting with cholelithiasis and common bile duct stones or papillitis, the sphincterotome was driven across the papilla into the choledochus by a Dormia basket passed in the duodenum through the cystic duct during laparoscopic cholecystectomy. Measures of outcome were clearance rate, mortality, morbidity and hospital stay. Furthermore, data obtained from this sample of patients were compared with those from another two groups of 16 patients in which choledocholithiasis was managed either by endoscopic sphincterotomy performed before laparoscopic cholecystectomy or by open cholecystectomy and trans-duodenal sphincterotomy. RESULTS: The rate of cannulation of the papilla and of the common bile duct stone clearance was 100% when the combined endo-laparoscopic approach was used in 15 patients with endoscopic sphincterotomy (93,7%) and in 15 patients with open sphincterotomy (93,7%), cholecystectomy was successful in every case. The groups were statistically similar with regard to complications; none of the patients required blood transfusion. The mean post operative stay was 95.2 hours (range 48-240) for the first group, 350.1 hours (range 192-1680) for the second and 69.7 hours (range 24-132) for the third. CONCLUSION: The laparo-endoscopic rendezvous, though still in evolution, is an efficacious method which can be used during the laparoscopic strategy of common bile duct clearance.  相似文献   

19.
The arrangement of the smooth muscle and elastic and collagen fibers of the minor papilla of the human duodenum was studied on 53 duodenopancreatic specimens obtained from adults of both sexes. Methods included stereological analyses of gross anatomical specimens and thick and thin microscopic sections. The muscular and elastic fibers of the minor papilla have a unidirectional arrangement by which the contraction of its smooth muscular fibers causes opening of its orifice allowing the flow of the pancreatic juice into the duodenum. It is not a typical anatomical sphincter.  相似文献   

20.
1. The effects of OKY-046, a specific thromboxane (TX) synthetase inhibitor, on blood pressure, urinary excretion of TX and its release from blood platelets and renal papilla, and pathological change of glomeruli were evaluated in Dahl salt-sensitive rats. 2. Average daily intakes of OKY-046-treated rats were 0.93 mg/kg (low dose), 9.8 mg/kg (moderate dose), and 88 mg/kg (high dose). 3. Systolic blood pressure tended to decrease by 6.3, 11.4, and 10.9% in three OKY-treated groups. 4. OKY-046 suppressed the release of TX from platelets in a dose-dependent fashion. Both TX in urine and released from renal papilla decreased in OKY-treated groups with moderate and high dose. OKY-046 resulted no change in urinary excretion or release from renal papilla of prostaglandin E2 or 6-keto-prostaglandin F1alpha. 5. Glomerular sclerosis score decreased significantly in both groups treated with moderate and high doses of OKY-046. 6. An inhibition of renal TX synthesis by TX synthetase inhibitor has a protective effect on the development of hypertensive renal damage with minor antihypertensive effect in Dahl salt-sensitive rats.  相似文献   

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