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101.
The prostate glands of 10 mature camels (3-5 years of age) were studied with the transmission electron microscope. Ultrastructural examination of the secretory acini showed 2 types of cells, i.e. tall secretory epithelial cells and basal cells. The cells both were characterised by rounded nuclei. The subnuclear cytoplasm was filled with abundant stacks of rough endoplasmic reticulum (RER). The RER was occasionally observed to be interconnected with whorls and networks of smooth endoplasmic reticulum (SER). In the supranuclear region, a moderate Golgi complex and a large number of secretory granules of varying sizes and electron density were observed. Lysosomes of various sizes were present in all types of cells. The luminal surfaces of the cells were covered with large number of microvilli. The basal cells were described. The ultrastructural morphology of the secretory units of the camel prostate may help us to determine if the mode of secretion in the camel prostate is apocrine in nature.  相似文献   
102.
103.
F Abdo  M Massad  M Slim  M Fahl  M Saba  F Najjar  G A Saad 《Surgery》1988,103(3):376-380
From 1980 to 1986, during the Lebanon war, five patients with missile embolization were seen at the American University of Beirut Medical Center. Three had entry in the heart or thoracic aorta with peripheral embolization, and two had entry in the internal carotid artery and inferior vena cava with embolization to the middle cerebral artery and heart, respectively. Embolization was suspected when, in the absence of an exit, routine x-ray films showed the missile in a distant location. Angiography and echocardiography confirmed the diagnosis. Peripheral arterial emboli were extracted while cerebral and venous emboli were kept, as they caused transient symptoms and remained silent.  相似文献   
104.
We report a case of familial sinus node disease with associated conduction abnormalities in the atrioventricular node and distal conduction system Spontaneous atrial pacemaker activity was absent though the atrium could be depolarized. The pacemaker activity of the heart resided in the atrioventricular junction. The AV node showed impaired automaticity and abnormal conduction properties which partially improved after vagal blockage.  相似文献   
105.
The effects of myenteric neuronal denervation on smooth muscle thickening and epithelial cell proliferation were studied in the descending colon of rats treated by serosal application of 2 mM benzalkonium chloride (BAC) for 30 min. Control animals were treated with saline (0.9% NaCl). The animals were divided into six groups of 13 animals each and killed 10, 45 and 120 days after BAC treatment. A significant reduction in neuron number was observed in the myenteric plexus of animals treated with BAC, as well as smooth muscle thickening and an increase in crypt cell population, crypt cell production per crypt and a decrease in cell cycle time. These findings permit us to conclude that a relationship may exist between the increase of epithelial cell proliferation, smooth muscle thickening and myenteric neuron denervation in the descending colon caused by BAC, the latter probably playing an important role in the integration of the other two.  相似文献   
106.
Seminiferous tubular boundary tissue thickens with age. The objective was to characterize the composition of boundary tissue in 16 young adult (20 to 29 years) and 18 older adult (51 to 84 years) men. Testes were perfused with glutaraldehyde, placed in osmium, and embedded in Epon 812 (Ladd Research Industries, Burlington, VT). Paired testicular weight, length of tubules, volume of seminiferous epithelium, and daily sperm production were significantly reduced in older men. Although the thickness of boundary tissue was greater (P less than 0.01) in older men, the volume of boundary tissue per man was similar between age groups. The percentages and volumes per man of boundary tissue myoid cells, collagen, microfibrils, and other components also were similar (P greater than 0.05) between age groups. This study confirms that age-related thickening of boundary tissue occurs without the new deposition (augmentation) of collagen or other extracellular components.  相似文献   
107.
A case of inherited bisalbuminemia was discovered in which electrophoretic controls showed that the proportion of the abnormal albumin decreased progressively during storage of the serum either at 4 degrees C or at room temperature. Such a decrease was also found when the serum was incubated with the proteolytic enzymes trypsin or plasmin. Studies with the isolated abnormal albumin showed that either during storage or after incubation with trypsin (or plasmin), its mobility became identical to that of normal serum albumin. Structural analyses showed that the albumin variant was identical to the previously described pro-albumin Christchurch that contains an additional N-terminal sequence: Arg-Gly-Val-Phe-Arg-Gln. It was therefore suggested that the progressive decrease of the abnormal albumin during storage by serum was related to the cleavage of the N-terminal abnormal sequence by plasmin already present in the serum. The decrease of the abnormal albumin during storage was inhibited by addition of cortisol to serum (1 mol per mol serum albumin). This was found related to a protective effect of cortisol bound to the albumin variant on proteolysis by plasmin.  相似文献   
108.
109.
Metastatic carcinoma to the testicle, epididymis, and their tunics is unusual and adenocarcinoma of the small bowel is extremely rare. The combination of primary adenocarcinoma of the jejunum with metastasis to the tunica vaginalis of the testis has not been reported previously. An unusual case of a scrotal mass in a twenty-seven-year-old black man is presented and the literature reviewed.  相似文献   
110.
A recurrent central giant cell granuloma in a 14-year-old girl in the anterior region of the mandible was treated successfully by intralesional injection of corticosteroid.  相似文献   
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