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31.
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   
32.
A prospective study was performed to determine the incidence of group B streptococci cultured from the cervix in a series of obstetric clinic patients at St. Margaret's Hospital. Cultures were taken during each trimester and planted to both a blood agar plate and a selective broth medium. Of a total of 812 cultures, 18 were positive, an over-all incidence of 2.2 per cent. During the first, second, and third trimesters, 2.2 per cent, 2.5 per cent, and 1.9 per cent of cultures were positive, respectively. Women with positive cultures were treated with a 10 day course of oral penicillin or a suitable alternative; four of 16 had persistent positive cultures at the end of the first treatment period, three of these four responded to a second course of antibiotics, and the remaining patient responded after a third treatment course. The total number of positive cultures by selective broth was 24, compared to nine in blood agar, indicating a 2.7-fold increase in pickup by the selective broth.  相似文献   
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Three cases of haematemesis associated with alcohol abuse are described. Early fibreoptic endoscopical examination in each showed a focal, well demarcated area of gastric mucosal haemorrhage, close to the oesophagogastric junction. Two patients showed prolapse of the lesion into the lower part of the oesophagus, and the third had coexistent Mallory-Weiss tears. Our observations suggest that forceful vomiting is responsible for this lesion, by causing abrupt retrograde gastrooesophageal prolapse. The prognosis of the lesion appears good.  相似文献   
34.
A 23-year-old woman suffering from multiple sclerosis (MS) was given a course of 6 injections (0.5 U) of mumps transfer factor (TF) at 2-weekly intervals. The patient's symptoms improved dramatically and during the 10 months since treatment was instituted, no exacerbations have occurred. The possible aetiological role of paramyxoviruses in MS and the use of TF in the treatment of the disease are discussed. MS is however, a disease of exacerbations and spontaneous remissions, and despite our promising findings in this patient we wish to refrain from hailing mumps TF as a possible cure for this notorious disease.  相似文献   
35.
Fifty-three patients 3 1/2 to 20 years of age with steroid-dependent idiopathic nephrotic syndrome (INS) were treated with cyclophosphamide and prednisone. Two dosage schedules were used: a short course (SC) at 3 to 5 mg/kg/day for six to eight weeks and a longer course (LC) at 3 to 5 mg/kg/day for eight weeks followed by 1.5 to 2.5 mg/kg for an additional four weeks. Prednisone was administered concurrently at 50 to 75 mg/sq M every other day. Twenty-nine patients were in the SC group and 24 in the LC group. The two groups did not differ significantly as to age at onset of idiopathic nephrosis nor as to the duration of the INS prior to cyclophosphamide therapy. All patients were followed for a minimum of 42 months after cyclophosphamide therapy. The SC was associated with a higher relapse rate during the first year than the LC (42% and 8% respectively, .01 larger than P less than .025). At 42 months 63% of the LC group were in remission compared with 21% in the SC group.  相似文献   
36.
The production of tumor-specific cell-mediated cytotoxicity following in vitro sensitization of C57BL spleen cells against a syngeneic 3LL Lewis lung carcinoma was studied. Lymphocytes were sensitized on monolayers of the tumor cells for 4-5 days. The cytotoxicity was assayed by measuring the reduction in 3H-leucine and 3H-thymidine incorporation by target cells after interaction with the sensitized lymphocytes. Spleen lymphocytes sensitized on monolayers of 3LL tumor cells caused a high extent of lysis; such cells tested on C57BL or C3H fibroblast targets evoked only a low level of cytotoxicity. C57BL spleen cells sensitized on C57BL fibroblasts caused a low level of cytotoxicity when tested on a 3LL target. Thus cytotoxicity appeared to be tumor specific. The reduced incorporation into protein and DNA of target tumor cells caused by the sensitized lymphocytes was a measure of cell injury, which was more sensitive than direct cell count or uptake of 51CR. Lymphocytes from syngeneic tumor-bearing mice, tested 13-25 days after tumor inoculation, did not manifest in vitro cytotoxicity. On the contrary, such lymphocytes sometimes appeared to have a promoting effect on the tumor cells.  相似文献   
37.
This paper explains the Canadian decision process following the isolation and identification of A/New Jersey/8/76 at Fort Dix, New Jersey in February 1976. The cause for concern was the emergence of a swine-like strain related to that which caused the 1918-19 pandemic, together with proved man-to-man transmission. This concern was reinforced since all new influenza A strains known to have infected the number of persons involved at Fort Dix have become strains of epidemic importance. The Fort Dix outbreak gave sufficient warning to allow implementation of a national vaccination program, to prevent and protect against influenza. In the past such an opportunity had not occurred, and vaccine use had, at best, constituted an intervention in the course of an outbreak. The National Advisory Committee on Immunizing Agents had all available information when it reached its decision to recommend vaccination with bivalent (A/Victoria and A/New Jersey) or with monovalent (A/New Jersey) vaccine for selective, high-risk groups. This was an independent, scientifically based decision.  相似文献   
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Lung function and immunologic studies have been performed in 9 patients with bird breeder's hypersensitivity pneumonitis at the time of diagnosis and at intervals from 8 to 30 months after they ceased exposure to the provoking antigen. All 9 patients had evidence of small airway obstruction at the time of diagnosis. Complete recovery of lung function occurred in 4 patients. The other 5 all had evidence of interstitial damage; 3 of them had progressive increase in the degree of airway obstruction, and one had progressive loss of elastic recoil. The patients were nonsmokers, and these progressive changes could not be explained by occult exposure to antigen because the tests of immunologic sensitivity to relevant avian antigens became negative. Neither the nature or degree of lung function abnormality nor the form of clinical presentation was related to the development of residual damage. The period of exposure to antigen after symptoms developed and the age of the patient appeared to be the most important factors determining recovery of lung function.  相似文献   
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