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排序方式: 共有641条查询结果,搜索用时 46 毫秒
61.
SJ Bersoff-Matcha MM Horgan VJ Fraser LM Mundy BP Stoner 《Canadian Metallurgical Quarterly》1998,178(4):1174-1177
Recent evidence suggests that sexually transmitted diseases (STDs) enhance the transmission of human immunodeficiency virus (HIV) type 1. In 143 HIV-infected women enrolled in a university-based longitudinal HIV clinic over 16 months (mean), the STD point prevalence was examined at enrollment and the cumulative prevalence was calculated at follow-up. At enrollment, 35 women (25%) had > or = 1 STD. These included trichomoniasis in 16 women (11%); syphilis, 9 (6%); genital herpes, 8 (6%); gonorrhea, 5 (4%); chlamydia, 5 (4%); genital warts, 2 (1%); and pelvic inflammatory disease (PID), 1 (1%). STDs were found in 55 (42%) of the 125 patients who returned for at least one follow-up visit: trichomoniasis in 23 (18%); genital herpes, 20 (12%); gonorrhea, 9 (7%); syphilis, 7 (6%); genital warts, 7 (6%); chlamydia, 5 (4%); and PID, 4 (3%). Despite counseling at both enrollment and follow-up, these women had a very high cumulative prevalence of STDs, indicating persistent high-risk sexual behavior. 相似文献
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63.
D Berry M Yao JA Barden VJ Balcar MA Hansen MR Bennett A Keogh CG dos Remedios 《Canadian Metallurgical Quarterly》1998,19(5):856-859
This is the first report of the analysis of the ATP-specific P2X1 receptor subunit in human hearts. We have examined homogenate samples of human left atria for the presence of P2X1 receptors using Western blots. Anti-P2X1 immunoreactivity was detected in populations of nondiseased atria as well as in atria from explanted hearts from patients with terminally failing heart conditions such as dilated cardiomyopathy. At least three groups of P2X1 immunoreactive proteins were detected in the Western blots with approximate molecular mass values of 50, 70, and 160 kDa. We report changes in expression of their 50 and 70 kDa components. These changes may be related to the type of deficit in these hearts since the changes have been observed in hearts with decreased ejection fractions characteristic of dilated cardiomyopathy. 相似文献
64.
H Wessells K Fuciarelli J Hansen ME Hadley VJ Hruby R Dorr N Levine 《Canadian Metallurgical Quarterly》1998,160(2):389-393
PURPOSE: We evaluated the erectogenic properties of a new cyclic alpha-melanocyte-stimulating hormone analogue, Melanotan-II, to treat men with psychogenic erectile dysfunction. MATERIALS AND METHODS: Ten men with erectile dysfunction of no known organic cause were entered in a double-blind, placebo controlled crossover study in which the erectogenic properties of Melanotan-II and a vehicle placebo were compared using real-time RigiScan monitoring. The presence, duration and rigidity of erections were recorded during a 6-hour period. RESULTS: In 8 of 10 men treated with Melanotan-II clinically apparent erections developed. Mean duration of tip rigidity greater than 80% was 38.0 minutes with Melanotan-II and 3.0 with placebo (p=0.0045). Transient side effects of nausea, stretching and yawning, and decreased appetite were reported more frequently after injections of Melanotan-II than placebo but none required treatment. CONCLUSIONS: Melanotan-II is a potent initiator of erections in men with psychogenic erectile dysfunction and has manageable side effects at a dose of 0.025 mg./kg. 相似文献
65.
EJ Bilsky RN Bernstein GW Pasternak VJ Hruby D Patel F Porreca J Lai 《Canadian Metallurgical Quarterly》1994,55(2):PL37-PL43
Evidence in vivo has suggested the existence of subtypes of the delta opioid receptor (DOR), which have been termed delta 1 and delta 2. These proposed DOR subtypes are thought to be activated by [D-Pen2, D-Pen5]enkephalin (DPDPE, delta 1) and [D-Ala2, Glu4]deltorphin (delta 2). Recent work in which an antisense oligodeoxynucleotide (oligo) to a cloned DOR was administered by the intrathecal (i.th.) route has demonstrated a reduction in the antinociceptive actions of both i.th. DPDPE and [D-Ala2, Glu4]deltorphin, but not of [D-Ala2, NMPhe4, Gly-ol]enkephalin (DAMGO, mu agonist) in mice. The present investigation has extended these observations by administering the same DOR antisense oligo sequence by the intracerebroventricular (i.c.v.) route and evaluating the antinociceptive actions of i.c.v. agonists selective for delta, mu and kappa receptors. I.th. treatment with DOR antisense oligo, but not mismatch oligo, significantly inhibited the antinociceptive actions of both i.th. DPDPE and [D-Ala2, Glu4]deltorphin but not of i.th. DAMGO or U69,593 (kappa agonist), confirming previous data. In contrast, i.c.v. DOR antisense oligo, but not mismatch oligo, selectively inhibited the antinociceptive response to i.c.v. [D-Ala2, Glu4]deltorphin without altering the antinociceptive actions of i.c.v. DPDPE, DAMGO or U69,593. The data suggest that the cloned DOR corresponds to that pharmacologically classified as delta 2 and further, suggest that this delta receptor subtype may play a major role in eliciting spinal delta-mediated antinociception. 相似文献
66.
MM Lewis VJ Watts CP Lawler DE Nichols RB Mailman 《Canadian Metallurgical Quarterly》1998,286(1):345-353
The role of drug efficacy in agonist-induced desensitization was studied in C-6 glioma cells transfected with the monkey dopamine D1A (mD1A) receptor. Dopamine pretreatment for 2 hr produced greater than 80% loss of responsiveness in the stimulation of cAMP accumulation that was blocked by the D1 antagonist SCH23390. A series of full and partial D1 agonists from structurally dissimilar classes were then examined. Three full agonists (dihydrexidine, SKF82958, A77636) desensitized the receptor to the same extent as dopamine, whereas two other full agonists (dinapsoline and A68930) and all the partial agonists tested (SKF38393, pergolide and d-lysergic acid diethylamide tartrate) produced only partial desensitization (i.e., 50% that of dopamine). Whereas partial agonists (i.e., SKF38393, pergolide and d-lysergic acid diethylamide tartrate) caused no alteration in ligand-accessible mD1A receptors, four of the full agonists (dopamine, dihydrexidine, dinapsoline, A68930) caused a 30 to 40% reduction in receptor number. One full agonist, A77636, caused nearly an 80% decrease in receptor number, despite the fact that the degree of functional desensitization was similar to the other full agonists. The desensitization of the D1 receptor was homologous, not affecting beta-2 adrenergic receptors endogenous to C-6 cells. Neither incubation with cAMP analogs, nor inhibition of protein kinase A, affected dopamine-induced desensitization, suggesting a cAMP-independent mechanism in this cell line. Together, these data suggest that functional desensitization of the mD1A receptor expressed in C-6 glioma cells is a cAMP-independent mechanism, cannot be predicted reliably from agonist efficacy for stimulating adenylate cyclase and can occur in the absence of changes in receptor number. 相似文献
67.
Continuing advances in PET imaging have resulted in an improved ability to evaluate thoracic malignancies. Published reports demonstrate that PET provides accurate, non-invasive detection and staging of thoracic malignancy. Preliminary studies suggest that PET may also be able to assess the therapeutic response accurately. The studies investigating PET have been relatively small but have shown statistically significant advantages over conventional non-invasive techniques in accuracy and possibly even cost/benefit performance in thoracic malignancies. 相似文献
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69.
BT Collins LJ Gardner AK Verma VJ Lowe FR Dunphy JH Boyd 《Canadian Metallurgical Quarterly》1998,42(6):1325-1329
OBJECTIVE: Patients with primary head and neck neoplasia can present during follow-up with suspected recurrence, and both fine needle aspiration biopsy (FNAB) and fluoride-18 fluorodeoxyglucose positron emission tomography (FDG-PET) scan are available methodologies for evaluating these patients. Our objective was to retrospectively correlate patients who underwent both FNAB and FDG-PET scan in order to assess the possibility of recurrent neoplasia. STUDY DESIGN: The cytopathology files at Saint Louis University Health Sciences Center were retrospectively searched for patients with known primary head and neck malignancies beginning in 1995. Suspected recurrence and local metastases evaluated by both FNAB and FDG-PET scan were correlated. RESULTS: Twenty-eight patients received a combined total of 37 FNABs with concurrent FDG-PET scans. The majority of patients had primary oropharyngeal squamous cell carcinoma with intermixed, single cases of other primary head and neck neoplasms. Thirty of the 32 aspirates with recurrent or locally metastatic disease had combined positive findings by both FNAB and FDG-PET scan, yielding a sensitivity of 94%. One nonspecific and one negative FDG-PET scan came from a patient who had disease confirmed by FNAB. Five patients had negative findings by both methods that were supported by the subsequent clinical course. CONCLUSION: FNAB can provide confirmatory evidence of disease in a clinically suspicious abnormality with nonspecific FDG-PET results. FNAB and FDG-PET are highly sensitive for tumors in cases of clinically suspected recurrence and locally metastatic disease. 相似文献
70.