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11.
Two autopsy cases of Cronkhite-Canada syndrome were reported. The caused of hypoproteinemia, electrolyte imbalance and ectodermal changes were discussed with reference to previously reported cases. The mechanism of protein loss was probably due to outflow into the intestinal lumen of the mucous substance in the cystically dilated glands, directly and/or indirectly followed by loss of mucosal surface. Electrolyte imbalance probably developed from gastrointestinal loss as well as poor substitution. The ectodermal changes were probably not a subsequent part of the emaciation or hypoproteinemis, but an inherent part of this disease. Therapy, whether substitution or surgical procedure, should be selected in order to control the general condition of the patient.  相似文献   
12.
SUMMARY.— Electron microscopic studies on embryonic hair development were performed using the scalp and eyebrow skin of 10 Negro embryos of the menstrual ages of 9 to 15 weeks. New ultramicroscopic findings were: (1) The peripheral cells of the hair germ extended into the mesenchyme pseudopodia, not covered by the basal lamina. (2) Mesenchymal cells crowded beneath the hair germ were connected with desmosome-like junctions. Direct contact of these cells with the basal lamina of the hair germ was seen. (3) A halfdesmosome- like structure was found between the mesenchymal cells and mesenchymal fine filaments.  相似文献   
13.
报道了若干呋喃西林类金属络合物的抑菌活性,数据表明:羰基氧原子换成硫后可使化合物活性所提高。它们与铜(Ⅱ)、锌(Ⅱ)、钴(Ⅱ)、镍(Ⅱ)等形成络合物后可使抑菌活性发生显著变化。  相似文献   
14.
To evaluate the effect of hepatitis B vaccine on the persistence of anti-HBs and its efficacy in preventing hepatitis type B, anti-HBs and anti-HBc levels were studied over a period of 5.5 years. Plasma-derived hepatitis B vaccine, containing 20 micrograms of HBsAg protein, was injected subcutaneously in 122 healthy medical staff members, followed by two identical injections 1 and 6 months later. Anti-HBs and anti-HBc levels were then measured by radio-immunoassay. The anti-HBs titres were expressed as the sample/negative (S/N) ratios, and an S/N ratio of more than 2.1 was considered positive. The mean (and s.d.) anti-HBs titre peaked 7 months after the first vaccination with an S/N ratio of 153.6 +/- 149.8, after which it decreased with time. The mean anti-HBs titre dropped to an S/N ratio of 8.0 +/- 5.1 5.5 years after the first vaccination. The percentage of vaccinees who were anti-HBs positive also gradually decreased with time after a peak of 84.2% at 7 months following the first vaccination. The percentage of vaccinees who were anti-HBs positive was 38.9% 5.5 years after the first vaccination. The anti-HBc level was not positive in all subjects during the observation period. Five vaccinated volunteers who had developed anti-HBs after the basic vaccination, but whose acquired antibody level became negative within 4.5 years following the first vaccination, were administered a booster dose of 20 micrograms of HBsAg 4.5 years after the first vaccination. Only one of these subjects did not respond to the booster vaccination.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
15.
Despite an increasing level of successful action against drug trafficking, international authorities remain concerned at the continuing problem and the association with other criminal activities. Social use of psychoactive substances has a long history and attitudes continue to change. The controls which governments impose over drugs also change, both with these attitudes and with the increasing knowledge of pharmacology and physiologic effects of drugs, sometimes over many years. Public opinion remains somewhat ambivalent and ideas of personal liberty and the desire to be protected from harm become confused. Governments must accept the responsibility to impose controls in the interest of the community's safety. They need to remain flexible, varying controls with experience, and with therapeutic need, taking into account patterns of utilization and the advent of more appropriate treatments. This requires full cooperation with the academic and professional communities and a climate which assists mutual understanding.  相似文献   
16.
The solution conformations of novel dipeptides, methyl (2S, 3′S)-3-methyl-2-(2′-oxo-3′-isopropyl-1′-piperazinyl)-butanoate (EVV-OCH3), methyl (2S, 3′S)-3-phenyl-2-(2′-oxo-3′-benzyl-1′-piperazinyl) propionate (EFF-OCH3), and their derivatives (Boc-Gly-EW-OH, Boc-Gly-EVV-Gly-OH, and Boc-Gly-EFF-OH), were studied by ‘H NMR measurements and molecular mechanics calculations (1). The molecular structures of Boc-Gly-EVV-OH, Boc-Gly-EFF-OH, and the hydrochloride of EVV-OCH3 were determined by X-ray analyses. The conformations of the piperazinone rings and the side chains of these oligopeptides were clarified.  相似文献   
17.
Hepatocellular carcinoma (HCC) represents an extremely poor prognostic cancer, which is mainly due to the high frequency of metastasis/recurrence after surgical operation. To detect the specific chromosome alterations  相似文献   
18.
COMMENTS     
Testicular dysgenesis syndrome encompasses low sperm quality, hypospadias, cryptorchidism and testicular cancer. Epidemiological studies and genetic data from familial cases suggest that testicular dysgenesis syndrome has a common etiology. The Y chromosome is known to encode genes that are involved in germ cell development or maintenance. We have therefore investigated if different classes of Y chromosomes in the general population (Y chromosome haplogroups) are associated with aspects of the testicular dysgenesis syndrome. We defined the Y chromosome haplogroups in individuals from different European counties who presented with either (i) oligo- or azoospermia associated with a Y chromosome microdeletion, (ii) unexplained reduced sperm counts (<20 x 10(6)/ml) or (iii) testicular cancer. We failed to find Y chromosome haplotype associations with either microdeletion formation or testicular cancer. However, in a study of the Danish population, we found that a specific Y chromosome haplogroup (hg26) is significantly overrepresented in men with unexplained reduced sperm counts compared with a Danish control population. The factors encoded by genes on this class of Y chromosome may be particularly susceptible to environmental influences that cause testicular dysgenesis syndrome. Our current data highlight the need for further analyses of clinically well-defined patient groups from a wide range of ethnic and geographic origins.  相似文献   
19.
20.
The reasons for morphological changes of urinary red blood cells (RBC) in patients with glomerulonephritis are still controversial. In order to evaluate the importance of mechanical damage by the glomerular basement membrane (GBM), we examined urinary RBC taken from the patients with two different diseases which have characteristic GBM changes. Urinary RBC taken from 20 patients with Alport syndrome and nine with thin GBM disease were examined using a scanning electron microscope. Nineteen out of the 20 patients (95.0%) with Alport syndrome showed ‘glomerular type’, while five of the nine patients (55.6%) with thin GBM disease showed ‘glomerular type’. These results suggest that more complicated GBM abnormalities cause more severe RBC distortion. Therefore, we conclude that mechanical damage by the GBM may be the major factor in dysmorphism of urinary RBC.  相似文献   
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