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1.
We isolated a novel RNA species from the unicellular cyanobacterium Synechococcus PCC6301 and determined its gene sequence. This novel RNA was termed 6Sa RNA from its length (185 nt). Cross-hybridization of 6Sa RNA to other related microorganisms suggests that its existence is restricted to the Synechococcus genus or related organisms. A high level of accumulation of this RNA was observed by Northern analysis, indicating that 6Sa RNA is stable in cells. Computer-aided prediction of the 6Sa RNA secondary structure also supports its stability.  相似文献   

2.
Epignathus is an extremely rare form of teratoma that arises from the palate or pharynx in the region of the basisphenoid (Rathke's pouch). This condition is associated with a high mortality rate caused by severe airway obstruction in the neonatal period, thus requiring prenatal planning and prompt surgical treatment after birth. The authors describe a case of a giant epignathus that was successfully resected followed by an uneventful recovery.  相似文献   

3.
The pro-opiomelanocortin (POMC) gene encodes adrenocorticotrophin (ACTH) which is derived from precursors by proteolytic cleavage. Congenital, isolated ACTH deficiency is rare but may be familial and fatal. The aetiology is unknown though defects at both hypothalamus and adenohypophysis have been postulated. We have studied a female presenting with hypoglycaemia in the neonatal period. When studied at 6 weeks of age, ACTH was unmeasurable even after injection of corticotrophin releasing hormone (CRH1-41). ACTH precursors, quantitated by two-site immunoradiometric assay, were clearly measurable prior to treatment and were stimulated by CRH1-41 and suppressed by glucocorticoid administration. Concentrations of POMC, N-terminal pro-opiocortin (N-POC) and beta-endorphin (beta-EP) were within the normal adult range during glucocorticoid replacement therapy; ACTH and beta-lipotrophin remained undetectable. The secretion of glucagon, measured by radioimmunoassay, in response to hypoglycaemia was normal. By sequencing polymerase chain reaction products from the patient's genomic DNA, the entire coding region of the POMC gene was established to be normal. The results are compatible with a cleavage enzyme defect.  相似文献   

4.
We investigated the in vivo effects of thalidomide on the production of tumor necrosis factor-alpha (TNF-alpha). An in vivo systemic release of TNF-alpha occurred after the injection of lipopolysaccharide (LPS) in male ddY mice, and the TNF-alpha serum levels reached 652.2 +/- 75.7 pg/ml 90 min after the injection of LPS (0.3 mg/kg, i. p.). When thalidomide (1, 3, or 6 mg/kg) was administered intraperitoneally 3 h before the injection of LPS (0.3 mg/kg, i. p.), thalidomide markedly enhanced LPS-induced TNF-alpha release in a dose-dependent manner. The TNF-alpha serum levels at 90 min were 640 +/- 58.6, 1985 +/- 132.6, and 2795 +/- 203.5 pg/ml, respectively, compared to 628.6 +/- 64.4 pg/ml in mice treated with LPS-alone. Pretreatment with a single injection of thalidomide (1, 3, or 6 mg/kg, i. p.) dose-dependently increased the subsequent mortality caused by a challenge with LPS (15 mg/kg, i. p.), a dose that caused death in 10% of the control mice. We conclude that thalidomide enhances in vivo TNF-alpha secretion and the lethality of LPS in mice.  相似文献   

5.
To investigate the role of occupation as a risk factor for hairy cell leukaemia a case-control study on 121 male, hairy cell leukaemia (HCL) patients, and 484 controls matched for age and sex, was conducted. We found significantly elevated risk for HCL among building painters (OR, 5.7; 95% CI, 1.6-20.8; based on six cases and four controls) and construction workers (OR, 3.3; CI, 1.2-9.2; based on seven cases and eight controls). Farming has been suggested as a risk factor in HCL. In this investigation farmers had an OR of 1.2 (CI, 0.6-2.3) and farm workers an OR of 1.5 (CI, 0.8-2.8). However, having ever worked in farming yielded an OR of 1.8 (CI, 1.1-2.9). Having grown up mainly in a rural area gave an OR of 1.4 (CI, 0.9-2.4). UV light has been suggested as a risk factor for non-Hodgkin's lymphoma (NHL). To evaluate the impact of UV exposure, classification of occupations as indoor, outdoor or mixed indoor/outdoor was made. Outdoor and mixed outdoor/indoor work yielded ORs of 2.3 (1.0-4.9) and 1.6 (1.0-2.5), respectively. When the effect of outdoor/indoor or mixed indoor/outdoor work was analysed using a scoring system the OR was 2.0 (CI, 0.9-4.4) for farmers compared with 0.8 (CI, 0.3-1.9) among non-farmers in the highest scoring group. There was no clear correlation between socioeconomic status as defined by the Swedish Socio-Economic Classification (SEI), and the risk of HCL. As many comparisons were made, the possibility of associations occurring by chance can not be excluded.  相似文献   

6.
BACKGROUND: Pattern dystrophies of the retinal pigment epithelium, an arrangement of a pattern of dots, lines, or branches, are infrequent fundus abnormalities. Adult onset foveomacular vitelliform dystrophy (AOFVD) is considered a subtype of pattern dystrophy. Onset occurs during middle age, with an accumulation of yellow-gray macular deposits in the deeper retinal layers. Typically electro-oculograms are mildly subnormal or normal. Genetic studies suggest an autosomal dominant inheritance with variable penetrance. CASE REPORT: A case of a 56-year-old Hispanic women with a 1-month onset of "wavy moving vision" in both eyes is presented. Previous ocular and family history were unremarkable. Ophthalmoscopic examination revealed yellow circumscribed subretinal lesions of one-third to one-half disk diameter in the foveal centers of both eyes. Fluorescein angiography revealed a circumscribed area of mottled hyperfluorescence surrounding a central hypofluorescent spot. The patient was diagnosed with AOFVD. Examination of the patient's children revealed retinal pigment epithelial disturbances in the two oldest daughters, consistent with pattern dystrophies. CONCLUSION: Our investigation supports an autosomal dominant inheritance pattern, as seen on pedigree. The presence of different pattern dystrophies within the same family suggests a common etiologic continuum.  相似文献   

7.
8.
We report CT and MRI findings in a girl with late-onset ornithine transcarbamylase deficiency, who presented with progressive somnolence. Both imaging methods showed signs of an acute cerebral ischaemia with new defects on follow-up. Despite an unusual clinical presentation, laboratory studies led to the diagnosis of this rare inherited metabolic defect.  相似文献   

9.
BACKGROUND: The optimal timing for surgery in patients with mitral regurgitation is disputed. Because of the frequency of left ventricular dysfunction, which is difficult to predict, early surgery has been recommended, but its potential benefits have not been demonstrated. METHODS AND RESULTS: The outcomes of 221 patients (mean age, 65 +/- 13 years; 71% males) with flail leaflets diagnosed with two-dimensional echocardiography between 1980 and 1989 who were eligible for operation were analyzed. Group I comprised 63 patients who had early mitral valve surgery (within 1 month after diagnosis). Group II comprised 158 patients initially treated conservatively (80 of whom were operated on later). Group I patients were younger (P=.009), had more symptoms (P<.0001), and were more frequently in atrial fibrillation (P=.023) than group II patients. There was no difference in ejection fraction between the groups. The early surgery strategy was followed by an improved overall survival rate (P=.028) and a lower incidence of cardiovascular deaths (P=.025), congestive heart failure (P=.046), and new chronic atrial fibrillation (P=.032), as confirmed by multivariate analysis (adjusted risk ratios of 0.31, 0.18, 0.38, and 0.05, respectively; all P<.02). CONCLUSIONS: In patients with mitral regurgitation due to flail leaflets, the strategy of early surgery versus conservative management is associated with an improved long-term survival rate, decreased cardiac mortality, and decreased morbidity after diagnosis. This outcome advantage suggests that early surgery is a reasonable treatment option to be considered in low-risk candidates with repairable valves and severe mitral regurgitation.  相似文献   

10.
Injuries to the musculature of the posterior compartment of the calf are a frequent cause of pain, particularly among athletes. The majority of ruptures and strains in this area occur in the gastrocnemius muscle and, to a much lesser extent, in the plantaris muscle. We present a case of an unusual cause of calf pain--an isolated rupture of the soleus muscle--that developed in a 15-year-old girl after participation in a volleyball match. The injury was confirmed by T1- and T2-weighted magnetic resonance imaging. In this case, magnetic resonance imaging was helpful; however, the cost effectiveness of its use for this injury has yet to be proved.  相似文献   

11.
OBJECTIVES: This study was performed to investigate the long-term outcome of patients with unstable angina within subgroups of the Braunwald classification. BACKGROUND: Long-term follow-up studies of patients with unstable angina are rare and date from more than two decades ago. This study was performed to establish the prognosis of different subgroups of patients with unstable angina (Braunwald criteria) during a 7-year follow-up period. METHODS: We registered a well defined group of 417 consecutive patients, admitted to the hospital for suspected unstable angina. The definite diagnosis was unstable angina in 282 patients (68%) and evolving myocardial infarction in 26; in 109 patients (26%), the symptoms were attributed to other or nonspecific causes. Patients with definite unstable angina were subclassified according to the Braunwald classification. Survival, survival without infarction and survival without infarction or intervention were determined for each class. RESULTS: After a median follow-up period of 94 months, the mortality rate in the first year was 6% and 2% to 3% in the following years. The frequency of revascularization was 47% in the first year, and that for myocardial infarction was 11% in the first year and 1% to 3% thereafter. The Braunwald classification appeared to be appropriate for risk stratification in the first year. However, at 7 years the event rates in all classes were similar. In particular, the Braunwald classification had no long-term impact on mortality or infarction rates. However, patients with acute angina at rest or postinfarction angina and patients with extensive anginal treatment had high intervention rates. CONCLUSIONS: To our knowledge, this study is the first to demonstrate that despite a complicated course during the first year, current management results in good long-term outcome in patients with unstable angina.  相似文献   

12.
The present study reports on the use of visual screening, a mildly aversive response suppression procedure, as a treatment for reducing compulsive behaviors in a four and one-half year-old developmentally disabled boy. Two distinct patterns of compulsive responding were observed: repetitive (stereotyped) shoe-related behaviors and a ritualistic shoe-related act. The effect of visual screening on repetitive shoe-related responses was initially evaluated in a laboratory setting under A-B-A-B-B1 experimental conditions and systematically extended to the classroom setting in multiple baseline fashion. Visual screening was also contingently applied as treatment for the shoe-related ritual, with the effects analyzed using a similar multiple baseline format across hospital residential unit and natural home settings. Results of the study indicated that visual screening was an effective treatment for suppressing both forms of the subject's compulsive responding and that it was an easily learned and administered procedure from both staff and parent perspectives. Follow-up data across 12 months were obtained and indicated that the effect of treatment was exceptionally durable.  相似文献   

13.
BACKGROUND: Advanced hyperparathyroidism refractory to active vitamin D continues to be a problem and frequently forces the nephrologist to resort to parathyroidectomy. One particular aspect is persisting advanced hyperparathyroidism after renal transplantation. Published information on this point is fragmentary. DESIGN: Retrospective analysis. PATIENTS: Between 1983 and 1995 a total of 456 patients with renal secondary hyperparathyroidism were subjected to parathyroidectomy (PTX) of whom 103 were transplanted or had at least a history of renal transplantation. The present analysis concerns 37 patients who had a functional renal graft at the time of PTX and were followed for up to 13 years. PTX was performed after an average of 36.7 months after renal transplantation. OUTCOME: Thirteen patients experienced rejection and became dialysis-dependent. Twenty-four patients had stable function of the renal graft. Seven patients died during follow-up. Hypoparathyroidism post-PTX developed in 4/37 patients, but could be overcome by replantation of cryoconserved parathyroid tissue. FREQUENCY ESTIMATE: A total of 2632 renal transplants were performed in the catchment area. As a minimum estimate 3.91% of patients with a functional graft required PTX. RECOMMENDATION: Parathyroidectomy should be considered early in cases with advanced secondary renal hyperparathyroidism, since renal transplantation does not necessarily guarantee reversibility of parathyroid overactivity.  相似文献   

14.
BACKGROUND: Objective determination of saphenopopliteal junction incompetency has eluded surgeons for many years. With the advent of duplex ultrasonography incompetency of the saphenopopliteal junction can be determined with an acceptable degree of clinical certitude. OBJECTIVE: This study was undertaken in order to determine the accuracy of duplex ultrasonography in studying the competency of the saphenopopliteal junction. METHODS: A total of 50 patients were included in the study, and the saphenopopliteal junction was studied bilaterally in each patient. The Biosound Phase II Duplex Ultrasound System with a 7.5-mHz B-mode imaging was used. RESULTS: The degree of accuracy of ascertaining the competency of the saphenopopliteal junction was approximately 96%. CONCLUSION: This test is reliable, and provides helpful information to the clinician.  相似文献   

15.
Thirty-three patients with cerebral palsy had iliopsoas transfers as part of their surgery for hip instability. All had total-body involvement, spastic cerebral palsy and none could walk. At the time of surgery, eight hips were subluxated and 39 were dislocated or severely subluxated. Mean follow-up was 8 years in patients between 8-25 years old. Forty-five of the 47 hips were located. Thirty patients had an accompanying scoliosis, and, in 10 patients, the rib cage impinged on the pelvis. Hip flexion had decreased in most patients. Sitting ability had not improved in any patient, and had in fact deteriorated in 50%.  相似文献   

16.
OBJECTIVE: To determine how well the extent of glucose abnormality, as reflected by the number of abnormal values on the 3-hour oral glucose tolerance test (GTT), correlates with the level of carbohydrate intolerance during pregnancy and with the severity of adverse outcome. METHODS: We followed 764 gestational diabetic women under a once-per-week fasting and 2-hour postprandial serum glucose monitoring system. The subjects were stratified by the number of abnormal values on their GTTs. The level of glucose control and incidence of large for gestational age (LGA) infants were then determined and compared with the findings in 636 gravidas with abnormal screening but all normal GTT values. RESULTS: Patients with one or more abnormal GTT values had comparable incidences of LGA infants, which were all significantly greater than that in the 0-abnormal group (23-27% versus 13%; P < .01). This difference was due to subjects with poor glucose control. The means of the GTT values for each sampling time were greater and the GTT periodicity (the time for the GTT curve to return to the fasting level) was longer with an increasing number of GTT abnormal values (zero versus one versus two versus three versus four abnormal values, P < .02). The mean fasting, 2-hour postprandial, and overall mean glucose values during the study were positively associated with the number of abnormal GTT values. CONCLUSIONS: One or more abnormal GTT values were associated with comparably elevated incidences of LGA infants in patients with poor glycemic control. Achievement of recommended glucose control decreased adverse outcomes to near normal levels.  相似文献   

17.
Two cases of lymphoma-associated acquired C 1-inhibitor deficiency are described. In both patients, C 1-inhibitor deficiency and related symptoms preceded the diagnosis of the underlying neoplasm by several months. C 1-inhibitor deficiency was most likely due to consumption following immunocomplex formation. In both patients, a close relationship between low levels of C 1-inhibitor and tumor relapse was observed during follow-up. These findings indicate that measurement of C 1-inhibitor and complement factor C4 can be used as markers of disease activity in affected patients.  相似文献   

18.
A rare case of primary pineal melanoma is reported. The patient was a 53-year-old woman who complained of a severe headache. Computed tomography and magnetic resonance images revealed obstructive hydrocephalus caused by a mass lesion in the pineal region. A biopsy was performed through an occipital transtentorial approach. A black pigmented solitary tumor was seen without leptomeningeal dissemination. Histologic examination revealed melanoma. Chemotherapy consisting of dacarbazine, ACNU, vincristine, and interferon was used. Follow-up imaging studies showed dramatic reduction of the tumor without recurrence for 4 years. This report demonstrates that a solitary primary intracranial melanoma without leptomeningeal dissemination and with rare mitoses may yield a good result with chemotherapy.  相似文献   

19.
BACKGROUND: Diabetic papillopathy is a benign unilateral or bilateral optic neuropathy with transient optic disk edema and minimal reduction in visual function. The optic disk edema typically resolves in a few months with no resulting optic atrophy and minimal or no decrease in acuity. The exact etiology of the disk edema is unknown, but theories include retinal vascular leakage into and surrounding the optic nerve and disruption of axoplasmic flow resulting from microvascular disease of the optic nerve head vasculature. CASE REPORTS: Two adult patients receiving insulin for type II diabetes mellitus manifested bilateral disk edema and minimal visual dysfunction. Both patients showed funduscopic evidence of mild-to-moderate nonproliferative diabetic retinopathy O.D. and O.S., and one patient had clinically significant macular edema in both eyes. The diagnosis in both cases was diabetic papillopathy. Both patients had significant resolution of their disk edema in 3 to 6 months, with stable acuities and no signs of optic atrophy. CONCLUSIONS: Although diabetic papillopathy is a well-known clinical entity in patients with type I diabetes, the clinical profile can be expanded to include individuals with type II diabetes.  相似文献   

20.
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