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排序方式: 共有414条查询结果,搜索用时 31 毫秒
1.
Endosonography in diagnosing and staging duodenal villous adenoma.   总被引:1,自引:0,他引:1       下载免费PDF全文
T L Tio  L H Sie  P C Verbeek  L T D Wit    G N Tytgat 《Gut》1992,33(4):567-568
Endosonography was carried out in a patient with an extensive juxtapapillary tumour. Radiology and endoscopy were unable to distinguish a villous adenoma from an invasive carcinoma. Endosonography revealed a mucosal hypoechoic tumour without penetration into the submucosa and muscularis propria. The common bile duct, pancreatic duct, and pancreas were normal. Lymph node abnormalities were not found. Based on the endosonography findings, local surgical tumour resection was undertaken instead of a Whipple procedure. The histology of the resected specimen confirmed the endosonography diagnosis.  相似文献   
2.
Heparin cofactor II is a plasma protein that inhibits thrombin rapidity in the presence of heparin. It is definitely distinct from antithrombin III by immunological and physicochemical criteria, protease specificity and glycosaminoglycan specificity. HC II inhibits thrombin (but not the other proteases of the coagulation or fibrinolysis), chymotrypsin and chymotrypsin-like enzymes. Dermatan sulfate and pentosan sulfate but not heparin sulfate increase the rate of thrombin inhibition by HC II. The physiological role of HC II is presently unknown. II is likely that its antithrombin activity in vivo is restricted to the areas rich in dermatan sulfate. An additional role may be related to the inhibition of various chymotrypsin-like proteases involved in protein activation or degradation in the tissues. So far, there is no clinical evidence for a physiological role of HC II. Vascular thrombosis associated to constitutional deficiency in HC II have been reported in several instance but epidemiological data are lacking. The metabolism of HC II is very similar to that of AT III. In contrast, the anticoagulant effect of dermatan sulfate is strictly dependent on HC II. As this glycosaminoglycan is effective in an experimental model of thrombosis, HC II appears to be a potential target for new antithrombotic drugs.  相似文献   
3.
A globalization of drinking seems to be taking place. Alcohol prevention and related research become more and more a topic of national and international interest. This in itself is a positive development. However, local and regional efforts are necessary too. This article makes a plea for a stronger emphasis on local and regional research. Different goals in local/regional alcohol research are distinguished.  相似文献   
4.
A variant strain of Rauscher leukemia virus (RLV-A) obtained from a transplantable murine monomyelocytic leukemia causes a disease characterized by frank anemia, wasting, hepatosplenomegaly and erythroblastosis. The involvement of platelets in this disease are reported here. The RLV-A induced a severe thrombocytopenia (25 percent of control level) at the terminal stage of disease. This thrombocytopenia was not associated with disseminated intravascular coagulopathy since the prothrombin times were always within normal limits. The partial thromboplastin time was elevated in the terminal stages of disease and was found to be associated with factor deficiencies, possibly owing to the presence of anti-factor antibodies, in the intrinsic coagulation pathway, especially factor VIII. Further, splenectomy did not abolish the thrombocytopenia, since splenectomized, virally infected animals also developed severe thrombocytopenia (29 percent of control levels). The ensuing splenomegaly during progression of disease was not the cause of the thrombocytopenia. A physiological response to the severe thrombocytopenia was the production of larger size platelets. At terminal stages of the disease, platelet volume increased to 4.2 mu 3 (normal is 3.0 mu 3). An increase in platelet volume was also observed in splenectomized, virally infected animals. Electron microscopy indicated that these circulating platelets contained c-type viral particles. Viral infection was associated with decreased life span of circulating platelets, as measured by 75Se-methionine at mid and terminal stages of the disease. Our results suggest that direct viral infection of platelets and/or megakaryocytes with subsequent cell lysis is a possible cause of the observed thrombocytopenia observed in RLVA-induced disease and may also occur in other retrovirally-induced diseases.  相似文献   
5.
A follow-up study was performed in 42 premature infants in whom serial neonatal ultrasound and a single neonatal MRI of the brain was normal, or showed mild periventricular white matter changes. The aim of the study was to evaluate the clinical significance of periventricular signal intensity changes on MRI and to compare the predictive value of neonatal MRI with that of ultrasound. The infants underwent repeated standardised motor assessments and developmental tests. MRI was repeated at the corrected age of 12 months. Pronounced periventricular signal intensity changes on neonatal MRI and periventricular echodensities (flaring) on ultrasound were associated with a high incidence of transient motor problems during infancy. The degree of echogenicity carried the highest predictive value, as compared to duration of flaring on ultrasound and degree of periventricular signal intensity change on MRI. It is concluded that signal intensity changes on neonatal MRI represent the same ischaemic change of the periventricular white matter as flaring on ultrasound and that routine neonatal MRI screening is not warranted in premature infants without clinical evidence of neurological problems and with normal or mildly abnormal ultrasound scans. Recording of the degree of echogenicity should become a routine procedure in neonatal cerebral ultrasonography.  相似文献   
6.
The relationship between MR patterns of brain damage and type or timing of perinatal hypoxia-ischemia was studied. MR images of 104 children with evidence of bilateral posthypoxic-ischemic brain damage and neonatal records were reviewed. Three different MR patterns were found. Periventricular leukomalacia occurred in 73 children, in 82% after a history of subacute or chronic hypoxia-ischemia, in 71% after preterm birth. Predominant lesions of basal ganglia and thalamus occurred in 21 children, in 95% preceded by acute profound asphyxia, in 85% after term birth. Multicystic encephalopathy occurred in 10 infants, in 70% preceded by mild signs of hypoxia-ischemia, followed by an unexpectedly severe encephalopathy, in 60% after term birth. Statistical analysis showed that the patterns of injury were primarily related to the type of hypoxia-ischemia. We conclude that the type of hypoxia-ischemia, rather than the postconceptional age at occurrence determines the pattern of brain injury.  相似文献   
7.
DNA-testing for BRCA1/2 or Lynch syndrome is possible from the age of 18 years, although surveillance usually starts at 25. Some patients regret their decision of testing before age 25. This retrospective study evaluates whether the testing age should be above 25 years to prevent adverse effects such as regret or decisional conflict, by determining the percentage and characteristics of patients reporting these problems. 111 of 219 patients (51 %) tested for BRCA1/2 mutations or Lynch syndrome between 18 and 25 years from July 1996 to February 2011, returned self-report surveys. Primary measures were regret, decisional conflict and family influence. Secondary measures included quality of life (QoL), coping style, impact of genetic testing, and risk perception. Median age was 27 [21–40] years, with 86 % female. 73 % was tested for BRCA1/2, 27 % for Lynch syndrome. Only 3 % reported regret, however 39 % had moderate (32 %) to severe (7 %) decisional conflict. Regression analysis revealed that decisional conflict was associated with more monitoring/neutral coping style (p < 0.03) or paternal/no family mutation (p < 0.02); there were no differences in QoL, impact or risk perception. 42 % were mutation carriers, showing equal decisional conflict to non-carriers. 68 % would recommend testing <25 years; 77 % desired surveillance <25 years if a mutation carrier. Almost no patient tested for hereditary cancer between 18 and 25 years regretted this decision. A third reported retrospective decisional conflict, especially those actively seeking information when faced with a threat and/or those with a paternal or unknown inheritance. These patients may benefit from decisional support and personalized information.  相似文献   
8.

Research question

Previous studies of aromatase inhibitors on male infertility have focused on men with low testosterone–oestradiol ratio of less than 10. Can aromatase inhibitors improve spermatogenesis in men with idiopathic male infertility with normal testosterone–oestradiol ratio?

Design

Prospective study of men with idiopathic severe oligozoospermia (sperm concentration <5 million/ml) carried out between February 2015 and March 2017. The objective was to assess if semen-analysis parameters improved after treatment with letrozole. Secondary objectives were to monitor the safety of letrozole in men, and to measure the alterations in serum FSH, LH, oestradiol and testosterone levels.

Results

Fifteen men with normal testosterone–oestradiol ratio (>10) were treated with letrozole 2.5 mg daily for 4 months. This produced a 5.5-fold increase in sperm concentration (P?=?0.0068). All men had increased total serum testosterone and suppressed oestradiol levels after treatment, thus raising the overall testosterone–oestradiol ratio (P < 0.0001). Adverse effects from letrozole were relatively minor and included loss of libido (54%), headaches (25%), fatigue (21%), weakness (13%), loss of hair (8%) and dry mouth (8%).

Conclusions

Letrozole improves sperm concentration and increases testosterone–oestradiol ratio for men with oligozoospermia who have normal testosterone–oestradiol ratio; its role in the treatment of male infertility may be extended to this group of patients. In addition, it is a relatively well-tolerated drug with no serious adverse effects.  相似文献   
9.
10.
Scand J Caring Sci; 2011; 25; 211–219
Evaluation of an assertive outreach intervention for problem families: intervention methods and early outcomes Families who experience a chronic complex of socio‐economic and psycho‐social problems are hard to reach with mainstream care. Evidence exists that the core of this problem lies in a problematic interaction between this type of family and current systems of care. The adults and children involved have needs in multiple domains, while the care system is fragmented and highlights well‐defined requests for help. To improve access to this target group, an assertive outreach intervention was implemented into the preventive child healthcare system in the Netherlands. Evaluation research was carried out to get a detailed insight into the content of this intervention. Also, early outcomes were examined. Information was gathered by interviews, attending meetings on method development, analysing registration forms and a survey on client satisfaction. Five intervention stages were identified: case finding, making contact, sustaining contact, developing a family plan and linking (arranging for services to be delivered). Practical support was used to build rapport and clear the way to the uptake of follow‐up help. The professionals delivering the intervention need a broad range of competencies to establish a working relation with the families and to link them to care and services. A good care network across professionals from various organisations must exist to provide a variety of linking options. Early outcomes indicate that professionals were able to get in touch with the families within a mean of 13.2 days. Goals of the intervention were mainly practical support (73%), starting new assistance for a child (63%) and starting new assistance for a parent (43%). Linking to care and services was attained in the majority of the cases and parents expressed satisfaction. The findings indicate that the studied intervention is a promising one. Some potent components can be indicated: the outreach approach, practical support, maximising participation of the family and building bridges between the family and (in)formal support and assistance.  相似文献   
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