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11.
In three cases of oligodendrogliomas, atypical cells rich in eosinophilic cytoplasm, resembling plump astroyctic or astroblastic cells, were studied under the electron microscopy. These cells showed finely granular cytoplasm with routine hematoxylin-eosin preparation; ultrastructurally, they exhibited abundant, round cytoplasmic bodies of autophagic-vacuole type, in addition to other fine structures characteristic of oligodendroglioma cells.  相似文献   
12.
Conformational properties of (2'-5') and (3'-5') CpC have been determined by proton magnetic resonance spectroscopy at 220 MHz. The ribose ring structures are predominantly 3E with the exception of the ring from the 2'-phosphate fragment of C(2'-5')pC which exhibits an 2E pucker. Bases are oriented anti with respect to the ribose and the conformations about C4'-C5', C5'-O5', C3'-O3' (C2'-O2') are gg, g'g', and g+ in equilibrium g-, respectively. The dimers exist as mixtures of stacked (g+g+ and g-g- about the P-O(C) bonds) and unstacked species at 20 degrees C. Stacking is estimated to be 35% in both dimers.  相似文献   
13.
Thuringiensin A, an exotoxin from Bacillus thuringiensis, a constituent of the microbial insectide thuricide has been found to inhibit mitotic spindle, condense and scatter chromosomes. It may therefore be a promizing tool in future cell biological studies.  相似文献   
14.
The paper deals with a study of 100 patients diagnosed as combined senile and vascular psychoses. It is marked that in classical cases of such combinations the disorder has 3 stages. On the first stage there is a predominance of vascular pathology. After 60 years of age (the second stage) the senile sumptomatology disguises many symptoms of vascular lesions. The third stage is characterized by a vascular catastrophe. In many cases of combined psychoses there may be complications of other somatic pathology and mainly of lung and liver disorders.  相似文献   
15.
beta-Ionone is found to stimulate considerably carotinoids synthesis in Blakeslea trispora. The stabilization of carotene-synthesizing ability of B. trispora in the presence of beta-ionine under prolonged incubation time is observed. Stabilization of polyribosomes in the presence of beta-ionine is observed when studying polyribosome content in B. trispora. A hypothesis is expressed on the existence of biochemical "receptors" as a linkage between synthesized protein and destroying mRNA.  相似文献   
16.
In this series of gonadoblastomas it appeared that the germ cells were the motivating force underlying either tumor proliferation or regression. The ultrastructural morphology confirmed the presence of undifferentiated gonadal cells with active steroid synthesis by the interstitial cells. The Call-Exner-like bodies which showed extensive calcification were composed of basement membrane material containing a sulfated mucosubstance. A histochemical comparison with the noncalcifying Call-Exner bodies of a granulosa-cell tumor differed only in their glycoprotein content. The calcium deposits were identified as oriented hydroxyapatite crystals by electron diffraction, and it is proposed that the basement membrane material serves as a nucleation site for calcification. High serum testosterone levels were correlated with the presence solely of interstitial cells in one case. The finding of a gonadoblastoma without the presence of a Y chromosome contradicts earlier proposals concerning the requirement of a Y chromosome for germ cell proliferation.  相似文献   
17.
18.
The course of 132 patients with documented acute diverticulitis was analyzed: 99 patients treated medically and 33 patients treated surgically were followed for an average of 9.2 years. Seventy-three per cent of the medical group and 79% of the surgical group had no further symptoms or hospital admissions as a result of their diverticular disease once they were recovered from the acute episode. For three-quarters of the patients, therefore, acute diverticulitis occurred as a single episode that responded to either medical or surgical management. Considering the morbidity and cost to the patient, the treatment of the patient recovered from acute diverticulitis should be medical, with operation reserved for complications.  相似文献   
19.
Hemangioma of scrotum   总被引:1,自引:0,他引:1  
  相似文献   
20.
The testosterone concentration in allantoic fluid between 90 and 150 days of gestation in cattle can be used to determine the fetal sex; values were 442 +/- 20-3 (S.E.M.) pg testosterone/ml for males fetuses and 215 +/- 8-2 pg/ml for female fetuses.  相似文献   
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