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991.
992.
In the autumn of 1967, plague broke out among hill people in western Nepal, a country that had not previously reported human plague. Two persons were infected from an active sylvatic focus at a grazing area 5 km from Nawra, the village where the epidemic occurred. The second patient introduced plague into the village where the rest of the cases occurred. Clinical and epidemiological evidence suggests that plague was spread both by the airborne route, resulting in 6 cases of tonsillar plague and 1 case of primary pneumonic plague, as well as by infected fleas, resulting in 17 cases of bubonic plague. Since no evidence of a rodent epizootic was uncovered in the village itself, and because of the distinct clustering of the bubonic cases, human-to-human spread of plague by infected ectoparasite vectors, presumably Pulex irritans, is thought to have occurred.  相似文献   
993.
994.
Rational management of patients with pulmonary thromboembolic disease should include assessment of the risk of additional emboli. Other authors have shown that the possibility of fatal pulmonary embolism is higher when the iliofemoral system contains thrombus, and it is recommended that vena caval interruption rather than simple anticoagulation is indicated. Additional factors governing the therapeutic choice should include the magnitude of the original embolic occlusion as well as the presence of antecedent cardiopulmonary disease. In these instances large thrombi in the iliocaval system should be regarded as potentially life threatening. A sequence of angiography beginning with right iliac and vena caval opacification, proceeding to pulmonary arteriography, and terminating with retrograde left iliac vein study provided information needed to individualize the therapeutic approach. Several case reports illustrate the spectrum of abnormalities and their therapeutic implications.  相似文献   
995.
The diagnosis of cancer in children challenges all the skills of the pediatric nurse. She utilizes her basic knowledge of development, family dynamics, and disease process. She explores all the implications of long-term illness. She assesses, plans, implements, and evaluates care for the child and his family. She acts as liaison, teacher, and counselor. She is the advocate for the child and his family. As an active member of the team she is instrumental in the process of rehabilitation for the child, physically and emotionally. She can help the child to live with cancer and assure quality of life in the days granted him.  相似文献   
996.
997.
998.
A comparative assessment of toxic element concentrations in serum and tissue bioptates in patients with laryngeal papilloma or cancer was performed. Examinations were conducted in 60 patients (40 men and 20 women) aged 20-88 years (average 59 +/- 05). Patients were divided into 3 groups; 20 patients with laryngeal papilloma were in group I, 20 with laryngeal cancer were in group II, and 20 with deviated nasal septums were included as a control group (III). Diagnosis of laryngeal papilloma (removed by direct microlaryngoscopy--Kleinsasser method) and laryngeal cancer (removed by the Rethi method) was histopatologically confirmed in patients from groups I and II, respectively. Patients in the control group received functional surgery to repair deviated nasal septums. Serum and tissue samples were obtained from all patients before surgery. Aluminum and lead concentrations were analysed by inductively coupled plasma atomic emission spectrometry (ICP-AES) using a Spectroflame M spectrometer. The considerable rise of aluminum and lead concentration in tissue bioptates and aluminum in serum in groups I and II in comparison to the control group suggests that these elements may play a significant part in the aetiology and development of precancerous lesions and laryngeal cancers. Measuring toxic chemical element concentrations in tissue bioptates can be useful in the diagnosis and estimation of development of precancerous lesions of the larynx as well as laryngeal cancer. Toxic elements concentration may play a significant role in carcinogenesis and may determine trends in cancer aetiology.  相似文献   
999.
1000.
Ovarian steroids are one of the strongest risk factors for breast cancer. Sex hormone-binding globulin (SHBG) binds and transports sex steroids in the blood, regulating their bioavailable fraction and access to target cells. It can also inhibit the estradiol-induced proliferation of breast cancer cells through its membrane receptor. Three coding-region polymorphisms, which lead to an amino acid change, have been reported. We studied the influence of these three polymorphisms on breast cancer risk in three different populations: Polish familial breast cancer cases, 27% of them carrying a BRCA1/BRCA2 mutation, Nordic familial and sporadic breast cancer cases. The reported G to A polymorphism in exon 1 was not found in the 423 analyzed samples. Instead, we found a C to T transition causing an arg to cys amino acid change within the same codon in one Polish breast cancer patient and her daughter. Both of them were heterozygotes for the exon 8 G to A polymorphism as well. They were diagnosed for bilateral breast cancer and carried a BRCA1 mutation (5382insC). Analysis of the tumor samples showed that they had lost the wild-type allele both at exons 1 and 8 of the SHBG gene. Analysis of the other Polish samples showed no correlation of the exon 8 polymorphism to breast cancer, bilateral breast cancer, BRCA1/BRCA2 mutations or age at diagnosis. No association of the exon 8 polymorphism with breast cancer in the Nordic familial or sporadic cases was found. The C to T polymorphism located in exon 4 was rare in all the studied populations (overall allele frequency 0.011). However, in each of the study populations there was a trend for a lower variant allele frequency in cancer cases than in controls. Variant allele frequency in all the breast cancer cases was significantly lower than in all the controls (chi(2) = 5.27, P-value 0.02; odds ratio = 0.23, 95% confidence interval 0.05-0.84).  相似文献   
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