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71.
该研究以山东万杰医学院为例,针对目前招生规模越来越大,生源质量不断下滑,大面积学生逃学、厌学、考试成绩不及格的严峻现实,提出有关教学方法、教学内容和考核方式的教学三项改革,这三项改革举措顺应了当前高校教育(特别是民办高校教育)形势的发展趋势。通过改革实践,已初见成效,进一步验证了只有坚定不移地搞好教学三项改革,才能保证和提高教学质量,从而使广大学生及其家长的利益得到充分保障;也只有大张旗鼓地继续搞好教学三项改革,学校才有生存和可持续发展的空间。  相似文献   
72.
The objective of this paper is to investigate the long-term outcome of primary antiphospholipid syndrome (APS) in the paediatric age. The features of unselected patients with primary APS who had disease onset before the age of 16 years were retrospectively analysed in three Italian referralcentres. Clinical and laboratory manifestations were assessed to establish whether, at the end of follow-up, the final diagnosis was still primary APS or whether they had developed definite SLE or lupus-like syndrome. Fourteen patients, nine boys and five girls, who had the presenting clinical manifestation of APS between three and 13 years of age (median nine years) and were followed for two to 16 years (median six years). Six patients presented with deep vein thrombosis, five with cerebral stroke, two with peripheral artery occlusion and onewith myocardial infarction. During follow-up, four patients had one or more recurrences of vascular thrombosis. At last observation, 10 patients could still be classified as having primary APS, two had developed SLE, one lupus-like syndrome and one Hodgkin's lymphoma. In conclusion; our analysis suggests that some children who present with the features of primary APS may progress to develop SLE or lupus-like syndrome.  相似文献   
73.
BACKGROUND: Antibodies against cyclic citrullinated peptide (anti-CCP) are considered to be specific for rheumatoid arthritis (RA). OBJECTIVE: To assess the clinical significance of anti-CCP in a cohort of patients with juvenile idiopathic arthritis (JIA). METHODS: Anti-CCP were tested by an enzyme linked immunosorbent assay (ELISA) in serum samples from 109 patients with JIA (30 boys, 79 girls), with a mean age of 8.7 years (range 0.6-20.3) and mean disease duration of 3.6 years (range 3 months to 15.6 years). As control groups, anti-CCP were also tested in sera of 30 healthy children, 25 patients with juvenile onset systemic lupus erythematosus (SLE), and 50 adult patients (30 with RA, 20 with SLE). RESULTS: Positive anti-CCP values were found in sera of two patients with JIA (2%), one with polyarthritis, and one with oligoarthritis. Statistical analysis showed that anti-CCP were not associated with the presence of antinuclear antibodies, raised erythrocyte sedimentation rate, or erosions. In the control groups, none of the patients with juvenile onset SLE and only one of 20 adults with SLE were positive for anti-CCP, but 19/30 (63%) adults with RA showed anti-CCP positivity. CONCLUSIONS: Anti-CCP can be detected in children with JIA, but are less frequently present than in adults with RA.  相似文献   
74.
In 24 cases of arrhythmogenic right ventricular (RV) dysplasia, the electrovectorcardiographic (ECG-VCG) behavior of T horizontal (wave and loop) was analyzed and the data compared with RV angiographic volumes. Arrhythmogenic RV dysplasia was diagnosed on the basis of echocardiographic and angiographic data in all subjects. At ECG, T wave was negative in V1 in nine subjects (37%), in V1-V2 in six (25%), in V1-V3 in two (8%), in V1-V4 in one (4%), in V1-V5 in two (8%), and in V1-V6 in four (16%). Nine subjects (37%) presented a bifid T wave in V2-V4. At VCG, T horizontal loop showed three morphologic characteristics: (1) counterclockwise rotation with a mean axis range of +15 degrees to -10 degrees (average, +5 degrees); (2) a figure-eight pattern with a mean axis range of +10 degrees to -40 degrees (average, -17 degrees); and (3) clockwise rotation with a mean axis range of -40 degrees to -110 degrees (average, -70 degrees). T wave changes seem to be primary and independent from QRS changes. RV and diastolic volumes ranged from 100 to 320 m1/m2 (average, 169 +/- 69). The extension of T wave negativity on precordial leads has a direct relationship with RV enlargement (r = 0.89, p less than 0.01). T changes are probably caused by dislocation of the left ventricle backwards secondary to RV dilatation, asynchronous RV repolarization, or intraparietal RV conduction defects.  相似文献   
75.
Cystic endocrine tumors of the pancreas rarely occur, and only a few cases of cystic insulinoma have been reported to date. Diagnosis of insulinoma could be difficult if the functional activity is incomplete, possibly leading to blunted symptoms of hypoglycemia and failure in the laboratory to provide evidence of hyperinsulinemia. We report a clinical case of cystic insulinoma confirmed by histological examination after surgery, characterized by a high intracystic insulin concentration despite normal blood basal levels of the hormone. New diagnostic findings from dynamic tests and cystic fluid examination have been carefully focused on.  相似文献   
76.
P Limonta  D Dondi  R Maggi  L Martini  F Piva 《Endocrinology》1989,124(2):681-686
It is known that the neural mechanisms which control PRL and gonadotropin secretion are different in male and female rats. The present experiments have been designed in order to analyze: 1) whether sexual differences exist in the responses of PRL and LH to the opioid antagonist naloxone; and 2) the mechanisms underlying these possible differences. To this purpose the responses of PRL and LH to the sc injection of either saline (0.5 ml) or naloxone (2.5 mg/kg) have been tested in the following four groups of animals: 1) normal male rats; 2) normal female rats; 3) female rats treated on the second day of life with 1.25 mg testosterone (androgenized female rats); and 4) male rats orchidectomized 2 days postnatally (demasculinized male rats). The naloxone challenge has been provided when the animals were 16, 26, and 60 days old; the animals were killed in the afternoon 20 min after treatment. The results obtained have shown that the acute injection of naloxone significantly decreases serum levels of PRL in normal males and in androgenized females at all ages considered. On the contrary, the opioid antagonist was always ineffective in normal females and in neonatally castrated males. The treatment of male rats with naloxone was without any effect on LH release before puberty (at 16 and 26 days of age), but induced a significant increase of serum LH titers after sexual maturation (60 days). In normal females, naloxone brought about a significant increase of serum LH only at 16 and 60 days (animals in estrus), but not at 26 days. Treatment with naloxone did not exert any significant effect on LH release in androgenized females and in deandrogenized males of any age. The present data suggest that, in the rat a sexual difference exists in the opiatergic control of PRL secretion; apparently, the central opioid systems which regulate PRL secretion develop towards a male pattern because of the presence of androgens in the neonatal period. On the contrary neonatal androgens do not seem to exert any important effect in directing the organization of the opiatergic mechanisms controlling LH release.  相似文献   
77.
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79.
Summary In addition to their usual diet, nine Type 1 (insulin-dependent) diabetic men and ten male control subjects took 20 g d,ga-tocopheryl acetate enriched evening primrose oil (14.45 g 182c,6, 1.73g 183c,6, 400 mg d,-tocopheryl acetate) daily for one week. At start, diabetic patients had more 140, 150 and 18 2c,6, and less 160, 161c,7, 181c,7, 183c,6, 203c,9, 203c,6, 204c,6 and 226c,3 in plasma, erythrocytes and/or platelets. Furthermore, they had lower 161c,7/160, 181c,7/160, and 204c,6/203c,6 ratios and a higher 203c,6/183c,6 ratio. In diabetic patients, -tocopherol levels in erythrocytes were lower, whereas those in plasma were normal. In both groups, oil intake changed fatty acid profiles. Most markedly, 203c,6 increased, whereas the ratios 203c,6/ 183c,6 and 204c,6/203c,6 decreased. 204c,6 increased in control subjects, but not in diabetic patients. Erythrocytes and platelets responded differently in their fatty acid profiles, -tocopherol rose in plasma and, although less for diabetic patients, in erythrocytes. In diabetic patients as well as in control subjects, erythrocyte count, haemoglobin level, mean corpuscular haemoglobin content and concentration increased and glycosylated haemoglobin percentage decreased without an apparent decline in blood glucose levels. Plasma -thromboglobulin and platelet factor 4 decreased, especially in diabetic patients. In conclusion, diabetic patients had abnormal fatty acid patterns, suggesting an impaired 9, 6 and 5 desaturation and an enhanced chainelongation, and had lower erythrocyte a-tocopherol levels; and short-term high dose intake of evening primrose oil increased 203c,6 in both groups, but 204c,6 only in control subjects, gave fatty acid responses which were different for erythrocytes and platelets, enhanced erythropoiesis, and lowered indices of in vivo platelet activation.  相似文献   
80.
The human gene for glucose-6-phosphate dehydrogenase (G6PD) has been subregionally mapped to band Xq28 by segregation analysis in rodent-human somatic cell hybrids [Pai, G. S., Sprinkel, J. A., Do, T. T., Mareni, C. E. & Migeon, B. R. (1980) Proc. Natl. Acad. Sci. USA 77, 2810-2813]. We have previously reported a common type of X-linked mental retardation associated with an inducible fragile site at Xq27-Xq28 segregates in a close linkage relationship with a G6PD variant, but the relative position of G6PD with respect to the fragile site has not yet been established. This fragile-X syndrome has been shown to be closely linked also to a Taq I restriction fragment length polymorphism detected by a cDNA probe for factor IX, and the latter locus has been mapped to the subtelomeric region Xq26-Xq28 [Camerino, G., Mattei, M. G., Mattei, G. F., Jaye, B. & Mandel, J. L. (1983) Nature (London) 306, 701-704]. The in situ hybridization studies reported here provide strong evidence that G6PD is located on the Xq telomeric fragment distal to the fragile site. These observations and the well-established knowledge that the genes for Deutan and Protan colorblindness are closely linked to G6PD, but segregate independently of factor IX deficiency, suggest that the fragile site associated with this type of X-linked mental retardation occurs in a region prone to high frequency of meiotic recombination.  相似文献   
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