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1.
A series of pyrroles bearing an ethanol- or an iso-propanolamine side-chain in the beta-position was prepared and their adrenergic activity evaluated. The absence of any appreciable activity suggests that the pyrrole ring is not suitable for replacing the phenol nucleus in derivatives possessing an adrenergic activity. Noteworthy is the amphetamine-like activity observed in amino-ketone (XXIII).  相似文献   
2.
We studied endocrine functions at baseline and after TRH and LHRH stimulation in a group of 7 young male patients with genetic hemochromatosis (HE) without liver damage (i.e. fibrosis and cirrhosis). In five patients endocrine re-evaluations after complete iron depletion was also performed. Mean basal testosterone (T), FSH, LH and PRL were significantly lower than in controls. Serum T increased normally after HCG stimulation. The normal or high increments of LH after LHRH stimulation suggest that secretion capacity of LH was intact and that hypothalamic dysfunction could be responsible for the preclinical gonadal deficiency found in our patients. The response of PRL to TRH indicates that secretion capacity of lactotrophs although present, was decreased and did not improve after phlebotomy therapy. After iron depletion the two patients with the lowest basal T levels showed the highest increments indicating that in the early stages of hypothalamic-pituitary damage gonadal dysfunction is still reversible in HE patients.  相似文献   
3.
BACKGROUND: Long-term intra-oesophageal acid suppression with proton pump inhibitors represents a management option for Barrett's oesophagus and severe reflux oesophagitis, but its stability over time has not been adequately assessed. AIM: Our aim was to evaluate prospectively the efficacy of proton pump inhibitors in suppressing intra-oesophageal acidity after 2-year continuous treatment. METHODS: Forty-five patients with Barrett's oesophagus or severe reflux oesophagitis on a proton pump inhibitor regimen (once or twice daily) that normalised the total percentage acid exposure time were re-evaluated by means of 24-h oesophageal pH-monitoring after 2-year of continuous unmodified treatment. RESULTS: A significant rise in the total percentage acid exposure time was observed at 2-year follow-up (P=0.029), owing to an increased value in 27 (60%) cases (9 on a twice daily regimen), higher than normal in 10 of them (22% of the whole group) (3 on a twice daily regimen). In 18 patients (40%) the total percentage acid exposure time was stable or decreased. Heartburn remained efficiently suppressed in all patients. CONCLUSIONS: The efficacy of proton pump inhibitors in suppressing intra-oesophageal acidity during continuous treatment may decrease over time, up to abnormal levels of oesophageal acid exposure in a minority of cases. This may occur without heartburn recurrence and with both once and twice daily regimens.  相似文献   
4.
Qualitative visual inspection and manual muscle testing are traditional methods of evaluation that may overlook subtle weakness of the axioscapular musculature. A modification of the standard technique of Moiré topographic analysis of spinal deformity was applied to assess axioscapular muscle function in 51 subjects: 22 asymptomatic individuals, 22 with shoulder instability, and seven with impingement syndrome. Static Moiré evaluation demonstrated scapulothoracic asymmetry or increased topography in 14% of asymptomatic subjects, compared with 32% and 57% in the instability and impingement groups, respectively. The dynamic Moiré test demonstrated an abnormal Moiré pattern in 18% of asymptomatic individuals, compared with 64% and 100% in the instability and impingement groups, respectively. Axioscapular muscle dysfunction is common with both instability and impingement syndrome of the shoulder, although it remains to be determined whether this represents a primary or secondary phenomenon.  相似文献   
5.
To investigate the age-dependent functional importance of cholinergic neocortical inputs, and to explore whether cortical cholinergic denervation in aged animals might better model the cerebral metabolic changes of Alzheimer's disease, the effects of unilateral ablation of the nucleus basalis magnocellularis (NBM) on cerebral glucose metabolism were studied in young and aged rats. Regional cerebral metabolic rates for glucose (rCMRglc) were determined, using the [14C]deoxyglucose method, in 48 brain regions of 3- and 24-month old Fischer-344 rats at 3, 7, 14 and 28 days after stereotaxic injection of ibotenate into the right NBM, and in sham-operated animals at 3 and 14 days later. For both ages the peak effect of unilateral NBM ablation occurred 3 days later: in young rats, rCMRglc was significantly reduced (compared to the contralateral side) in all 24 anterior cortical areas examined (mean decline 20%), whereas in aged animals, only 9 of 24 areas showed a significant decline in glucose utilization, and the magnitude of rCMRglc reduction (9%) was smaller. Near complete recovery of rCMRglc occurred by 7 days in young and old rats. We conclude that the basalocortical cholinergic projection plays a smaller role in neocortical function of aged rats, possibly because its tonic activity is reduced. Both young and aged rats undergo cortical metabolic normalization after unilateral NBM ablation; hence the NBM-lesioned aged rat is not a better model of the progressive decline in rCMRglc that occurs in Alzheimer's disease.  相似文献   
6.
BACKGROUND: Although mixed states were classically described as various concomitant admixtures of depression and mania, the official current definitions in both DSM-IV and ICD-10 tend to restrict the concept to manic patients with full syndromal depression. Recent research has actually shown that mania with few depressive symptoms constitutes the most prevalent clinical presentation of mixed or dysphoric mania. Major depressive patients with few concomitant manic symptoms are not officially recognized within the current nosology. In this paper we attempt to delineate the clinical profile of such depressive mixed states in the context of bipolar I disorder. METHODS: In the Pisa day center, we studied 195 bipolar I patients who either met Pisa criteria for bipolar mixed state (n=159) or DSM-III-R criteria for major depressive episode (bipolar major depression or B-MD, n=36). Of the 159 patients identified by Pisa criteria as mixed state, 86 also met the criteria of the DSM-III-R for mixed episode (core mixed state or MS group), while 32 met the DSM III-R criteria for major depressive episode (provisionally defined as depressive mixed states, D-MS); the remaining patients (n=41, 25.7%) with predominatly manic picture were not included in the present comparisons. RESULTS: The three groups (B-MD, MS and D-MS) had close similarities in clinical and sociodemographic characteristics such as age, sex distribution, marital status, schooling, residence, age at onset, age of first treatment, age of first hospitalization, degree of chronicity of the index episode, stressor within the 6 months before the index episode, lifetime suicide attempts and premorbid temperament. First degree family history for bipolar illness and that for other mental disorders was also similar, except for major depression that was more common among the relatives of D-MS. MS and D-MS were further distinguished from B-MD by the fact that the latter followed a more 'cyclic' course with shorter yet greater number of episodes, and which began with a pure depressive episode; by contrast, MS and D-MS had fewer episodes of longer duration, less interepisodic remission, and tended to begin with a mixed episode. Incongruous psychotic features were more common in the two mixed groups compared to B-MD, and the most common features of the D-MS group were agitation, psychotic depression with irritable mood, pressured speech and/or flight of ideas. LIMITATION: It was not feasible to collect information blind to clinical status in patients with severe psychotic mood states. CONCLUSION: These data confirm the existence of psychotic agitated depressive mixed states with flight of ideas, distinct from cyclic retarded pure bipolar depressive states. The recognition of these affective states is clinically important to protect patients from the potentially harmful indiscriminate use of antidepressants and to provide them with the benefits of an anticonvulsant, a short-term neuroleptic, or ECT.  相似文献   
7.
CDK9 is a member of the CDC2-like family of kinases. Its cyclin partners are members of the CYCLIN T family (T1, T2a, and T2b) and CYCLIN K. The CDK9/CYCLIN T1 complex is very important in the differentiation programme of several cell types, controlling specific differentiation pathways. Limited data are available regarding the expression of CDK9/CYCLIN T1 in haematopoietic and lymphoid tissues. The aim of this study was to analyse the expression of the CDK9/CYCLIN T1 complex in lymphoid tissue, in order to assess its role in B- and T-cell differentiation and lymphomagenesis. CDK9/CYCLIN T1 expression was found by immunohistochemistry in precursor B and T cells. In peripheral lymphoid tissues, germinal centre cells and scattered B- and T-cell blasts in interfollicular areas expressed CDK9/CYCLIN T1, while mantle cells, plasma cells, and small resting T-lymphocytes displayed no expression of either molecule. CDK9/CYCLIN T1 expression therefore appears to be related to particular stages of lymphoid differentiation/activation. CDK9 and CYCLIN T1 were highly expressed in lymphomas derived from precursor B and T cells, from germinal centre cells, such as follicular lymphomas, and from activated T cells (ie anaplastic large cell lymphomas). Hodgkin and Reed-Sternberg cells of classical Hodgkin's lymphoma also showed strong nuclear staining. Diffuse large B-cell, Burkitt's lymphomas, and peripheral T-cell lymphomas, among T-cell lymphoproliferative disorders, showed a wide range of values. No expression of CDK9 or CYCLIN T1 was detected in mantle cell and marginal zone lymphomas. However, at the mRNA level, an imbalance in the CDK9/CYCLIN T1 ratio was found in follicular lymphoma and diffuse large B-cell lymphomas with germinal centre phenotype, and in the cell lines of classical Hodgkin's lymphomas, Burkitt's lymphomas, and anaplastic large cell lymphoma, in comparison with reactive lymph nodes. These results suggest that the CDK9/CYCLIN T1 complex may affect the activation and differentiation programme of lymphoid cells. The molecular mechanism through which the CDK9/CYCLIN T1 complex is altered in malignant transformation needs to be elucidated.  相似文献   
8.
9.
Activated protein C (APC) resistance is an established risk factor for venous thromboembolism. In 5% to 10% of patients with venous thromboembolism, the APC resistance phenotype is observed in the absence of factor V Leiden mutation. Moreover, some physiologic and pathologic conditions are associated with an "acquired" APC resistance, not caused by the Leiden mutation, such as inflammatory diseases, pregnancy, or oral contraceptive therapy. Several studies have demonstrated the effect of menopause on the hemostatic system, but no data are available about APC resistance. We found a high prevalence of APC resistance in postmenopausal women, not associated with factor V Leiden mutation. The mechanism that underlies this acquired APC resistance may be related to the higher levels of factor VIII, which showed a strong inverse correlation with APC resistance, whereas no correlation was found between the normalized APC ratio, factor V levels, and protein S values. Higher levels of factor VIII correlated with a marker of coagulation activation, such as prothrombin fragments 1 plus 2. Therefore, to identify women receiving hormone replacement therapy who have a greater risk for deep venous thrombosis, the APC resistance coagulation test should be used instead of the genetic study.  相似文献   
10.
This case series reports the outcome of posterior ankle decompression and os trigonum or Stieda process resection utilizing an open posterolateral approach in 54 professional, pre-professional, and dedicated recreational dancers. All procedures were performed by a single surgeon at the same facility between 2008 and 2018. The surgical technique is described in detail. Data related to results of the surgery were gathered via follow-up questionnaire and verified by referencing the patients’ medical records. Outcomes were self-assessed in terms of categories ranging from excellent through moderate to poor. Eighty-nine percent of the dancers (N = 48 of 54) chose excellent or good, 11% (N = 6) chose moderate, and none selected poor. These results were compared with those achieved in 17 previous studies reporting the use of both open (posterolateral and posteromedial) and arthroscopic/endoscopic techniques in dancers. This comparison found similarly favorable reported outcomes, but also great variation in methodology for determining patient reported outcomes (PROs). While the preferred surgical technique for posterior ankle decompression remains controversial, the open posterolateral approach utilized in this series resulted in high expectation of return to dance with minimal complications. The need for a dancer-specific PRO tool is discussed.  相似文献   
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