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排序方式: 共有308条查询结果,搜索用时 31 毫秒
1.
Intratemporal vascular tumors: detection with CT and MR imaging   总被引:1,自引:0,他引:1  
The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion.  相似文献   
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Blood donation behavior of Hispanics in the lower Rio Grande Valley   总被引:2,自引:0,他引:2  
WW Thompson 《Transfusion》1993,33(4):333-335
This study was designed to determine the blood donation behavior and attitudes of Hispanic residents of the Lower Rio Grande Valley for the purpose of developing promotional and educational approaches to enhance levels of donor participation. Personal interviews of 545 respondents were conducted in English and Spanish using quota sampling and standard intercept techniques at lower- and middle-income supermarkets in five cities during a payday weekend. A number of research hypotheses were established to test for demographic, behavioral, and attitudinal differences that were observed in donors and nondonors using chi-square analysis and multiple discriminant analysis. After analyzing the difference between Hispanics and non-Hispanics for blood donation rates, all non-Hispanics were eliminated from analysis, and the remaining 419 Hispanics were evaluated on the basis of their donor behavior. Donation among Hispanics was most likely to be by better- educated, English-speaking, higher-job-status individuals who had participated in a blood donation drive. Donors tend to have parent(s) who were donors, and they were also more likely to carry an organ donor card. Donors were found to vary in their behaviors as well as their attitudes and beliefs. Perceptions of a lack of safety in donating, the risk of contracting acquired immune deficiency syndrome, and the financial motivation of donors were most pronounced among Hispanics, which indicated a need for improved education on these issues.  相似文献   
4.
COPD is one of the leading causes of mortality and increased morbidity in developed world. In advanced disease it also imposes an important economic burden on societies. The main etiologic factor for COPD is tobacco smoking. The aim of the study was to asses if the awareness of airflow obstruction combined together with a minimal antismoking advice in middle aged smokers increases the quitting rate. Out of smokers participating in mass spirometric screening for COPD in five polish towns, we invited 734 (300 with airflow limitation and 247 with normal lung function) for a follow-up. During the second visit, at one year, spirometry was performed and smoking status was assessed. Non-smoking was validated with carbon monoxide measurements in exhaled breath. Patients who did not come for the follow-up visit were considered as smokers. Of 734 smokers invited, 543 (74%) presented for the follow-up visit. All smokers tried to modify the habit. Number of cigarettes smoked at one year was reduced by -5.5 (p < 0.001) in patients with airflow limitation and -2.2 (ns) in smokers with normal lung function. One year quit rate in smokers with airflow limitation was 11.1% vs 7.6% in smokers with normal lung function (ns). When the calculation was made for those who had the follow-up the quit rates were 15.1% vs 9.9% (p < 0.05). Cessation of smoking was correlated with lung function. Those smokers who stopped smoking permanently or tried to quit had lower FEV1 (p < 0.01) and FEV1/FVC (p < 0.05), than those who continued to smoke.  相似文献   
5.
COPD is the most frequent chronic lung disease in Poland. The disease is however under-diagnosed, especially at the early stages. The aim of the study was to assess the efficacy of spirometric screening for COPD in middle aged smokers. Informations on causes and symptoms of COPD were disseminated in mass media in 14 large cities. Subject aged over 39 and with smoking history of > 10 packyears were invited for a free spirometry in local chest clinic. However, everyone attending had the spirometry performed. Spirometry was performed according to ATS recommendations. Airway obstruction (AO) was diagnosed when FEV1/FVC < 85% of N and categorised as mild (FEV1 > 70% of N), moderate (FEV1 50-69% of N) or severe (FEV1 < 50% of N). Spirometry was accompanied by an antismoking advice. RESULTS: 12.781 subjects were screened (mean age 52 +/- 12 years, 57% males). In 8.269 subjects who complied with inclusion criteria AO was diagnosed in 29.8% (mild in 10.9%, moderate in 12% and severe in 6.9%). In smokers < 40 years of age and a history of < 10 packyears AO was found in 8.8% (mild in 6.0%, moderate in 1.8% and severe in 1.0%). CONCLUSION: Mass spirometry is an effective and easy method for early detection of COPD.  相似文献   
6.
The role that maternal and fetal human leukocyte antigen (HLA) genes play in pregnancy is unknown, but it has been suggested that fetuses whose HLA alleles do not differ from maternal alleles (i.e. histocompatible fetuses) are more likely to be aborted than fetuses with HLA alleles that differ from maternal alleles (i.e. histoincompatible fetuses). To elucidate the role of HLA compatibility in pregnancy, we tested the hypothesis that couples who match for HLA alleles or haplotypes would have reduced fertility because only these couples could produce histocompatible fetuses. We conducted a 10 year prospective study of HLA matching and pregnancy outcome in 111 Hutterite couples, providing information on 251 pregnancies. A logistic regression analysis was performed to determine the effects of HLA matching at HLA regions and loci on pregnancy outcome (fetal loss versus delivery). Significantly increased fetal loss rates were observed among couples matching for the entire 16-locus haplotype (P = 0.002). Among the individual loci, loss rates were increased among couples matching for HLA-B (P = 0.019), HLA-C (P = 0.033) and the complement component, C4 (P = 0.043). We interpret these results as evidence that matching for the entire 16-locus haplotype and/or alleles at an HLA-B-linked locus confers significant risk for fetal loss.   相似文献   
7.
Marrow regeneration after mechanical depletion   总被引:1,自引:0,他引:1  
Brecher  G; Tjio  JH; Smith  WW; Haley  JE 《Blood》1976,48(5):679-686
The origin of marrow regeneration after mechanical depletion was reinvestigated in mouse chimeras. The results were compatible with the local origin of stem cells from remnants of incompletely removed marrow, but not with their origin from a common precursor of both bone and hemopoietic cell lines. In transplanted femurs depleted by a modified technique of in vivo evacuation of marrow, hemopoietic regeneration failed to occur. The presence of hemopoietic stem cells in the Haversian canals was thus excluded. The demonstration of ample hemopoiesis with minimal bone formation in nondepleted controls in which bone marrow initially became necrotic provided new evidence that osteogenesis was not a prerequisite of hemopoietic regeneration.  相似文献   
8.
The efficacy and safety of vigabatrin (VGB) has been extensively evaluated in preclinical and clinical studies but level of effectiveness in different type of seizures has yet to be established. The aim of our study is the prospective evaluation of anticonvulsant efficacy and toxicity of VGB. This long-term observation mainly focusing on efficacy of VGB in partial vs. secondarily generalized seizures were considered separately. In our study the criterion of drug resistance is occurrence per month of at least 1 tonic-clonic seizure or at least 2 complex partial seizures in 3 following months. The studies are based on 73 patients (39 F and 34 M), with average age of 26 years. After two weeks of treatment with sabril the drug was withdrawn in 5 patients because of side effects. The period of observation was 12 months. In group I--from total of 73 patients with partial seizures (including secondarily generalized)--31 (42%) of patients suffered only from partial seizures. Complex partial seizures occurred in 18 of patients; in this group were also 13 patients with simple partial seizures. Group II consisted of 42 patients (58%) who suffered from secondarily generalized tonic-clonic seizures. Number of seizures in group of patients with tonic-clonic seizures was from 1 to 16 per month (average 3.4) and in group of patients with complex partial seizures was from 1 to 70 per month (average 13.29). After titration period, Vigabatrin was given in doses of 500 to 3500 mg daily. Mean monthly fit frequency was calculated for over 3 months prior to the addition of vigabatrin and 12 months of therapy at the patient's maximum dose. Monthly fit frequency expressed as mean +/- standard error of the mean, and this statistical significance was determined using MANOVA for repeated measurement. Average monthly fit frequency of partial seizures has been reduced from 13.29 to 6.96 (p < 0.0001) and of generalized seizures from 3.38 to 1.38 (p < 0.0001). The percentage of patients achieving an increase of at least 75%--(Ratio < -0.6)--of seizures was greater in generalized seizures (27.3) than in partial ones (21.3). VGB is effective and well tolerated in refractory patients requiring add-on antiepileptic treatment and it has shown efficacy both in therapy of refractory partial seizures as well of secondarily generalized ones.  相似文献   
9.
The glenohumeral joint is inherently unstable because the large humeral head articulates with the small shadow glenoid fossa. Traumatic anterior dislocation of the shoulder is a relatively common athletic injury, and the high frequency of recurrent instability in young athletes after shoulder dislocation is discouraging to both the patient and the treating physician. Management of primary traumatic shoulder dislocation remains controversial. Traditionally, treatment involves initial immobilisation for 4–6 weeks, followed by functional rehabilitation. However, in view of the high recurrence rates associated with this traditional approach, there has been an escalating interest in determining whether immediate surgical intervention can lower the rate of recurrent shoulder dislocation, improving the patient’s quality of life. This review article aims to provide an overview of the nature and pathogenesis of first-time primary anterior shoulder dislocations, the widely accepted management modalities, and the efficacy of primary surgical intervention in first-time primary anterior shoulder dislocations.  相似文献   
10.
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