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1.
2.
A case of papillary adenoma of type 2 pneumocytes is reported. A 57-year-old man had an unusual coin lesion in the periphery of the right lung without any symptoms. When detected in a mass survey examination, it was approximately 1.5 cm in diameter, well circumscribed, and located in S4, involving the sixth-order bronchus of B4. Light-microscopic examination revealed cuboidal tumor cells arranged in a papillary pattern. Ultrastructurally, the cells had characteristic osmiophilic lamellar bodies. By immunoperoxidase staining, the tumor cells were shown to have intracytoplasmic surfactant apoproteins. The postoperative course was uneventful, and there is no evidence of disease 8 years later.  相似文献   
3.
We have recently demonstrated that a single injection of the mitogen lead nitrate to rats induced a rapid increase of tumor necrosis factor-alpha (TNF-alpha) mRNA in the liver and suggested that this cytokine may be involved in triggering hepatocyte proliferation in this model of direct hyperplasia. In this study, we examined whether a similar induction of liver TNF-alpha mRNA could be observed preceding the onset of hepatocyte proliferation induced by ethylene dibromide, another hepatocyte mitogen. In addition, we used dexamethasone, a well known inhibitor of TNF-alpha production, to determine whether its administration could suppress hepatocyte proliferation induced by lead nitrate and ethylene dibromide. A single intragastric administration of ethylene dibromide (100 mg/kg) to male Wistar rats enhanced liver TNF-alpha mRNA after 4 and 7 hours, which then returned to control levels by 24 hours. TNF-alpha mRNA was detectable only in a nonparenchymal cell fraction of the liver. Pretreatment of rats with a single dose of dexamethasone (2 mg/kg) 60 minutes before lead nitrate (100 mumol/kg) or ethylene dibromide completely abolished the increased levels of liver TNF-alpha mRNA induced by these agents. Inhibition by dexamethasone of TNF-alpha mRNA was associated with an inhibition of liver cell proliferation induced by these mitogens, as measured by [3H]thymidine incorporation into hepatic DNA, mitotic index, and DNA content. These results further support the hypothesis that TNF-alpha may be involved in triggering hepatocyte proliferation induced by primary mitogens.  相似文献   
4.
Two markers for the progenitor cells of peripheral airways and their tumors are the 10 kilodalton (kd) Clara cell protein and the major surfactant associated protein-A (SP-A). We used the RNA-RNA in situ hybridization technique to study expression of the genes encoding these proteins at the cellular level in 19 pairs of non-neoplastic and neoplastic tissues from resected human lungs. Our results show that in non-neoplastic lung tissue, the Clara 10 kd protein gene was expressed in nonciliated cells of both bronchial and bronchiolar epithelium, indicating that, in contrast to previous assumptions, cells with Clara cell-like differentiation in humans may not be restricted to bronchiolar cells. The incidence of Clara 10 kd protein gene expression, as detected in lung carcinomas (1 out of 19 cases positive) was less than expected based on previous ultrastructural reports. The SP-A gene was strongly expressed in normal alveolar type II cells in non-neoplastic lung and, at higher levels, in hyperplastic cells. In addition, SP-A mRNA expression was observed in scattered bronchial and bronchiolar epithelial cells in 40% of the airways examined. Five out of 17 lung tumors, all of which were adenocarcinomas, were positive for SP-A expression, albeit generally less intense than type II cells. This expression was seen in carcinomas with papillolepidic as well as solid and glandular growth patterns. Our findings provide new insights into the peripheral airway cell differentiation.  相似文献   
5.
An antibody to a protein produced by Clara cells in adult Syrian golden hamsters has been used to monitor the development and functional differentiation of secretory cells in the conducting airway epithelium of this species. Lungs from fetal and neonatal hamsters at gestational day 11 and at intervals up to and including 3.5 weeks of age (as well as adults) were studied. The earliest time this Clara cell protein could be identified by immunoperoxidase labeling in the fetal conducting airways was at gestational day 15. On this day, labeling was observed in a few secretory cells lining the trachea, in many lining the lobar bronchi, and in virtually all secretory cells lining the bronchioles. Ciliated cells and endocrine cells were not labeled. Granules first appeared within the apical cytoplasm of the secretory cells on gestational day 15 at all airway levels. To identify the exact subcellular location of this protein, an ultrastructural labeling procedure using protein A gold was employed. The gold particles labeled only electron-dense granules within the secretory cells, indicating that they represent the specific site of this protein. Since secretory cells in the most distal conducting airways began to produce this protein on the same day in development as cells in the larger airways, including the trachea, this expression of functional maturation occurs simultaneously throughout the conducting respiratory tree rather than proceeding sequentially in a cranial to caudal direction. Consequently, secretory cells lining the smaller conducting airways mature more rapidly than those lining the larger airways.  相似文献   
6.
We present a rare case in which a young girl ingested a solution of a hair-removing soap. The ingestion resulted in profound hypokalemia and severe acidosis leading to flaccid paralysis, respiratory arrest and ventricular arrhythmias. Ultimately the patient made complete recovery. The soapwas found to contain barium sulfide. The degree of paralysis and acidosis appeared to be directly related to serum potassium levels.  相似文献   
7.
8.

Objectives

To compare intravenous paracetamol and intramuscular tramadol as labor analgesics.

Methods

This prospective-randomized study conducted in 200 primigravidae in active labor, distributed into two groups of 100 women each with one receiving intravenous 1,000 mg Paracetamol and other 100 mg intramuscular tramadol. Pain intensity is recorded by McGills scale before, one and 3 h after drug administration. Perinatal outcome is recorded.

Results

No difference in pain intensity is seen before drug administration. After 1 h of drug administration, in paracetamol group, 4 % women had horrible pain, and 29 % had distressing pain, while in tramadol group, 30 % women had horrible pain, and 60 % had distressing pain. After 3 h of drug administration, in paracetamol group, 26 % had distressing pain, while in tramadol group, 51 % women had horrible pain, and 35 % had distressing pain. Labor duration in paracetamol and tramadol group was 4.3 and 5.9 h, respectively. In paracetamol group, nausea is seen in 2.2 % and vomiting in 1.1 %, while in tramadol group, nausea is seen in 6.4 % and vomiting in 4.3 %.

Conclusions

Intravenous paracetamol is more effective labor analgesic with fewer maternal adverse effects and shortens labor as compared to intramuscular tramadol.
  相似文献   
9.
Temporomandibular joint ankylosis is a unique disease where fracture of the mandibular condyle or any other cause leading to ankylosis of the joint can lead to multiple problems if not detected and treated early. If affected in early years of life, it may cause facial dysmorphism, restricted mouth opening, and difficulty in eating, speech, and sleep. Early surgery and physiotherapy can restore the joint function to a great extent. Anesthetizing a pediatric patient with this disorder is a definite challenge which needs expertise in difficult airway management.  相似文献   
10.
Cardiac echinococcosis--a rare echocardiographic diagnosis.   总被引:3,自引:0,他引:3       下载免费PDF全文
A 30 year old female admitted for evaluation of left chest pain was suspected to have multiple cardiac hydatid cysts. The diagnosis was established by cross sectional echocardiography and computed tomography, supported by enzyme linked immunosorbent assay (ELISA) for echinococcosis. Medical therapy altered the echopattern of the cysts but failed to reduce cystic masses. Surgery was advocated but refused by the patient.  相似文献   
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