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61.
62.
It is well established in animal models that production of the cytokine tumour necrosis factor-alpha (TNF-alpha) is essential to the proper expression of acquired specific resistance following infection with Mycobacterium tuberculosis. This gives rise to an apparent state of chronic disease which over the next 100-200 days is characterized by slowly worsening pathological changes in the lung. To determine whether continued TNF-alpha production was harmful during this phase mice were treated with a TNF-alpha inhibitor, pentoxifylline. It was observed that although this therapy did not alter the numbers of bacteria recovered from the lungs of the infected mice, tissue damage within the lung was accelerated. These data thus demonstrate that production of TNF-alpha, already known to be important during the early expression of resistance to tuberculosis, remains important and beneficial during the chronic stage of the disease.  相似文献   
63.
OBJECTIVE: Gynecologic disease is common in HIV-infected women. We examine the sociodemographic, clinical, and provider factors associated with the care of women with vaginal symptoms. METHODS: Women enrolled in the HIV Cost and Services Utilization Study (HCSUS), a nationally representative probability sample of HIV-infected adults, were interviewed between January 1996 and April 1997. Women with vaginal symptoms who sought medical attention were asked, "Did your health care provider examine your vaginal area?" Women were also asked if they received medication for their symptoms. RESULTS: Among 154 women with vaginal symptoms, 127 sought care for their symptoms. Of those who sought care, 48% saw a gynecologist and 52% sought care from nongynecologists, most often their usual HIV care provider. Women who saw a gynecologist for their symptoms were more likely to have received a pelvic examination (92% versus 76%; p =.06) and vaginal fluid collection (98% versus 88%; p =.06) than those who saw their regular HIV provider. Fifteen percent of women received medication for their symptoms without having a pelvic examination; gynecologists were less likely to prescribe without an examination (8% versus 21%; p =.12). CONCLUSION: Gynecologists are more likely to provide adequate care of vaginal symptoms among HIV-infected women than nongynecologists who were HIV care providers. This specialty difference is consistent with quality of care studies for other medical conditions, but the potential gynecologic complications of inadequate evaluation and treatment warrants further investigation.  相似文献   
64.
pFc' fragments (corresponding to homology region Cγ3) and smaller subfragments produced by trypsin and papain have been studied by haemagglutination inhibition techniques for the presence of a range of Fcγ allotypic markers. The markers which were identified in the pFc' fragment included Gm(a), (x), (b0), (b3), (b4), (b5), (c3), (c5) and `non a'. In addition, an IgG 4 marker which possibly occupies the same molecular region as the Gm(a) and `non a' antigens was detected in pFc' fragments from IgG 4 proteins.  相似文献   
65.
66.
The structural polypeptides of accepted species and recently isolated members of the genus Orthopoxvirus have been examined by SDS-polyacrylamide gel electrophoresis. The viruses shared many polypeptides but some differences were found. The viruses could be divided into a vaccinia group (including buffalopox, 'Lenny' and MK-10), an ectromelia group (including elephant virus and Moscow virus), cowpox, camelpox and monkeypox. Minor differences were found in the polypeptides of monkeypox virus strains from human and monkey outbreaks. Controlled degradation of virions showed that the polypeptides which enabled the viruses to be differentiated were located in the surface and sub-surface layers. The cores of the viruses all gave the same complex polypeptide pattern.  相似文献   
67.
Scleroderma is an enigmatic rheumatic disorder of uncertain etio-pathogenesis. Cancer has an approximately two-fold higher incidence in scleroderma patients than in the general population. There are preliminary data of acquired genetic damage in scleroderma but the significance of these observations are uncertain. To determine somatic mutation frequency at the glycophorin-A (GPA) locus in patients with limited and diffuse cutaneous scleroderma. The GPA assay measures the total somatic mutation frequency (Vf), composed of gene inactivating mutations (NO) and mutations arising from mitotic recombination (NN) in individuals heterozygous for the GPA MN blood group. Mutation frequency was determined using a validated GPA flow cytometric assay using fluorescent labeled monoclonal antibodies specific for the GPA blood groups M and N. This assay detects and enumerates progeny of red blood cell (rbc) precursor cells which have acquired genetic damage resulting in a loss of expression of one of the GPA alleles. It was found that patients with scleroderma (n = 23) had significantly elevated Vf as compared with young healthy controls (p < 0.001) and elderly controls (p = 0.03). Patients with diffuse scleroderma had higher mean Vf as compared with limited scleroderma (p = 0.055). In comparison with controls, patients with scleroderma exhibit a higher proportion of mitotic recombinant mutations than inactivating mutations (p < 0.002). There was no correlation between Vf and disease duration, age at onset or autoantibody status. We have documented evidence of acquired genetic damage at the GPA locus in scleroderma. Evidence of acquired genetic damage in this disorder may be importance in explaining both the etio-pathogenesis of scleroderma and the association of scleroderma with cancer.  相似文献   
68.
69.
SUMMARY  Obstructive sleep apnoea (OSA), and snoring are associated with coronary heart disease. To assess whether OSA or snoring may contribute to this by raising fasting lipid or insulin levels, venous fasting total cholesterol, triglyceride, very-low-density lipoprotein, low-density lipoprotein, high-density lipoprotein, and insulin were measured in 15 untreated OSA patients and 18 snorers. Each of these subjects was individually matched to a control of the same sex, age ± 10%, body index ± 15%, smoking and drinking habits. This produced study groups which did not differ significantly by any of these criteria. Fasting venous blood samples were collected at 06.30 hours following polysomnography, and analysed blind of the subjects respiratory status. The OSA patients were then treated with nasal continuous positive airway pressure. In 10 of these subjects lipid and insulin levels were repeated after more than three months treatment. Lipid and insulin levels were also remeasured in the controls matched to these 10 subjects. The end points were compared with paired t -tests.
There was no difference in any of the end points when the untreated OSA patients and the snorers were compared to their matched controls ( P >0.25 for all comparisons), and none of the indices changed when OSA was corrected with nasal continuous positive airway pressure ( P > 0.25 for all comparisons).
Patients with obstructive sleep apnoea or snoring do not have significant fasting hyperlipidaemia or hyperinsulinaemia when compared to carefully matched controls. These factors are therefore unlikely to be the cause of the excess cardiovascular mortality experienced by this patient group.  相似文献   
70.
Serum concentrations of fucose, sialic acid, and eight acute phase proteins were measured in single specimens from patients with cancer in order to determine whether the raised concentrations of protein bound sugars commonly found in cancer correlate with increased concentrations of the acute phase proteins. Strong positive correlations were found only with alpha 1-acid glycoprotein, alpha 1-antitrypsin, and haptoglobins. Changes in protein bound sugars and acute phase proteins were also examined in relation to patients' disease states. Serum fucose was raised more often in patients with advanced disease than in those in whom the spread of the tumour was more restricted; increased sialic acid concentrations, however, were found with a similar frequency in both these groups. Combined use of fucose and sialic acid values gave a high degree of marker positivity which could be only slightly improved on by including measurement of acute phase proteins. The combined use of serum fucose and sialic acid concentrations may have value in monitoring patients with cancer: the sialic acid provides an index of the acute phase response and the fucose a measure of the tumour spread.  相似文献   
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