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991.
This article reviews the appropriate workup of the patient presenting with complaints referable to a joint, including the important information to be obtained during the interview and physical examination, as well as from laboratory and imaging studies. The clinical presentation of osteoarthritis, rheumatoid arthritis, gout, and joint sepsis are discussed, and the treatment approach for each is outlined. The specific indications for surgical intervention in the course of arthritis also are detailed.  相似文献   
992.
Closantel (Flukiver), a salicylanilide antiparasitic compound, was tested in Korean native goats infected with Fasciola hepatica. The goats were administered closantel once orally at a dose of 10 mg/kg body weight. Efficacy was monitored weekly by fecal examination of all infected animals starting the second week post-treatment and continuing for 3 weeks. Closantel elicited 80.3, 97.8 and 92.7% efficacy in goats with naturally-acquired fasciolosis at the second, third and fourth week post-treatment, respectively. It elicited a 100% efficacy in goats experimentally infected with F. hepatica metacercariae and treated at 18 weeks post-infection.  相似文献   
993.
The effects of atrial natriuretic peptide (ANP) and C-type natriuretic peptide (CNP) on single-unit activity of dorsomedial arcuate (DM-ARC) neurons were reported. The modulatory effect of CNP on dopamine's (DA) action was also studied. ANP alone in 0.05-0.5 nmol doses induced 26% inhibition and 14% excitation of 37 DM-ARC neurons; the majority (60%) were not responsive. CNP, however, inhibited 46% and excited 4% of 74 DM-ARC neurons. Dose-dependent inhibitory effects of CNP were also observed. In 71 neurons tested with both CNP and DA, more neurons were inhibited by DA (66%) than those by CNP (46%). About one-third (34%) of them were inhibited by both. Furthermore, in 41 neurons inhibited by DA, more than half (54%) of their responses were potentiated by co-administration of CNP. In conclusion, CNP by itself exhibited a predominantly inhibitory action on DM-ARC neurons; and it also potentiated the inhibitory effect of DA on these neurons.  相似文献   
994.
995.
The proportion of women infected with the human immunodeficiency virus (HIV) continues to increase. Over one-half of women acquire the virus through heterosexual contact. The diagnoses that define the acquired immunodeficiency syndrome and the use of antiretroviral therapy are similar in men and women, except in pregnancy. However, management decisions differ significantly regarding contraceptive and gynecologic care. Besides abstinence, use of the latex condom continues to be the most effective way of preventing transmission of HIV. The management of human papillomavirus-associated disease, pelvic inflammatory disease and vaginal candidiasis is especially challenging in women with HIV infection. A positive status for the virus does not appear to affect pregnancy outcome. Each year, up to 2,000 infants are born infected with HIV. Transmission can occur by transplacental or intrapartum spread or through breast milk. Since 1994, prophylaxis with zidovudine has been shown to be an effective method of limiting transmission to infants. It is important to offer all pregnant women a test for HIV, with counseling provided both before and after the test, even if testing does not become mandatory under the law.  相似文献   
996.
BACKGROUND AND PURPOSE: Previous studies have suggested that recovery of cognitive function after stroke is maximal within the first 3 months after onset. We performed the present study to investigate the long-term course and clinical correlates of improvement in generalized cognitive function after ischemic stroke. METHODS: We administered a battery of neuropsychological tests to 151 patients (age, 70.4 +/- 7.7 years; education, 10.4 +/- 4.6 years) at 3 months and then annually after stroke. We transformed their test results into z scores based on the performance of a stroke-free normative group, averaged those scores to create a summary score, and defined improvement in annual examinations as an increase in that summary score greater than two standard deviations above the mean first annual change of the normative group. We then used logistic regression to determine whether stroke location, syndrome, or recurrence; vascular risk factors; dementia status; depression; or demographic variables were associated with improvement. RESULTS: We found that 19 of the 151 patients exhibited improvement, which was evident only at the first annual examination in most cases. Logistic regression determined that improvement was significantly related to left hemisphere infarction relative to brain stem/cerebellar infarction (odds ratio [OR], 5.57), while the presence of a major hemispheral stroke syndrome showed a trend toward significance (OR, 3.32). Diabetes mellitus was significantly associated with a failure to exhibit improvement (OR, 0.12). Based on the logistic model, the probability of long-term improvement would be 54.0% for a patient with a left hemisphere infarct and a major hemispheral syndrome but only 11.9% if diabetes was also present. CONCLUSIONS: Long-term improvement in generalized cognitive function may be evident after stroke in association with left hemisphere infarction and severe hemispheral syndromes, while it may be compromised by diabetes, possibly because of an increased burden of cerebrovascular disease.  相似文献   
997.
Topoisomerases are enzymes that catalyse the transient breakage and rejoining of either one (topo I) or two (topo II) DNA strands, to allow one strand to pass through another and prevent unresolvable tangles during processes such as DNA replication. A number of important clinical antitumour agents act through inhibition of topo II enzymes, while some topo I inhibitors appear likely to enter clinical use. Although these chemicals do not covalently interact with DNA, they have strong mutagenic potential, generally causing events at the level of the chromosome rather than that of the gene. Most are recombinogens, may affect gene expression and can also lead to aneuploidy through effects on chromosome segregation. Most topo I and topo II inhibitors primarily cause mutagenic events associated with the replication fork. However, at least in mitotic chromosomes, topo II enzymes are located at the base of chromosome loops, and topo II inhibitors may facilitate subunit exchanges, leading to major deletions and illegitimate recombinational events. There is evidence that programmed cell death provides an alternative pathway to mutagenesis following treatment by either topo I or topo II inhibitors. The final fate of the cell will result from a balance between these two processes.  相似文献   
998.
999.
AIM: To investigate the immunopathological changes in duodenal tissues induced by strongyloidiasis and to relate these to degrees of clinical severity. METHODS: Tissues taken from 21 patients showing mild, moderate or severe symptoms of strongyloidiasis, and from non-infected controls, were sectioned and stained immunocytochemically for IgA, secretory component (SC) and HLA-DR. Immunopathology was assessed by changes in numbers, intensity and distribution of stained cells. RESULTS: Parasitised individuals showed villous atrophy and crypt hyperplasia. There was notable infiltration of the lamina propria by IgA positive plasma cells and of the epithelium by intraepithelial lymphocytes. Infection was also associated with increased expression of SC and decreased expression of HLA-DR in epithelial cells. Changes in all parameters correlated with degree of clinical severity. CONCLUSIONS: Profound mucosal changes are induced by strongyloidiasis. Some are analogous to those seen in coeliac disease, but others seem quite unusual. It is likely that these changes are functionally related to the immunopathophysiological consequences of infection seen in patients with severe disease.  相似文献   
1000.
Cyproterone acetate (CPA), a synthetic progestin recently found to induce genotoxic effects in hepatocytes from female rats and from humans of both genders, and two structural analogues, chlormadinone acetate (CMA) and megestrol acetate (MGA), have been compared for their capacity to induce DNA repair synthesis as measured by quantitative autoradiography. Exposure of primary human hepatocytes for 20 h to concentrations of CPA, CMA and MGA ranging from 2 to 50 microM induced positive responses in cultures from donors of both genders and the amounts of DNA repair elicited by the three progestins were similar. Under the same experimental conditions substantial differences were observed in the amounts of DNA repair elicited by the three progestins in primary hepatocytes from female rats, their potency decreasing in the following order CPA > CMA > MGA, and the three compounds failed to induce DNA repair in hepatocytes from male rats. These results, which agree with previous findings, suggest that for these sex steroids extrapolation to humans of results obtained in rats might be questionable.  相似文献   
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