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排序方式: 共有231条查询结果,搜索用时 15 毫秒
121.
Ragni MV; Tegtmeier GE; Levy JA; Kaminsky LS; Lewis JH; Spero JA; Bontempo FA; Handwerk-Leber C; Bayer WL; Zimmerman DH 《Blood》1986,67(3):592-595
Antibodies to the AIDS retrovirus, specifically to human T cell lymphotropic virus, type III, and AIDS-associated retrovirus, were detected with increasing prevalence in a population of 190 hemophiliacs from western Pennsylvania between 1981 and 1984: 7.7% in 1981, 20.0% in 1982, 45.5% in 1983, and 62.5% in 1984. The seropositive included approximately three fourths of those receiving factor VIII concentrate, nearly one third of those receiving factor IX concentrate, nearly one fifth of those receiving cryoprecipitate, and none of those receiving fresh frozen plasma. The seroconversion rate, determined on 43 seropositive hemophiliacs from this group who were serially sampled, was 0% in 1977, 4.7% in 1978, 4.9% in 1979, 2.6% in 1980, 10.5% in 1981, 52.9% in 1982, 87.5% in 1983, and 100% in 1984. Of 27 seropositive for three or more years (since 1982 or before), four (15%) have developed AIDS and seven (26%), diffuse lymphadenopathy (ARC); of 16 seropositive for less than three years, none has developed AIDS and three (19%) have developed ARC. The mean time from seroconversion to onset of ARC, 0.8 +/- 0.2 years (SEM), was shorter (P less than .001) than the time to onset of AIDS, 4.1 +/- 0.6 years. These findings confirm the widespread presence of AIDS retrovirus and support the association of these retroviruses with the acquired immunodeficiency syndrome and related conditions. 相似文献
122.
To the editor: Shao Xinxin and colleagues recently described a case of duodenal stump leakage caused by Taenia saginata (T.saginata). Apparently, they did not identify the discharged adult tapeworm recovered after the treatment neither morphologically nor molecularly. The authors concluded that the species responsible for the symptoms was T. saginata based on the fact that the patient mentioned that he had been infected by T. saginata two years ago. 相似文献
123.
124.
Effects of recombinant human erythropoietin on megakaryocytes and on platelet production in the rat 总被引:8,自引:1,他引:7
The contention that erythropoietin (Epo) affects platelet production was investigated in the rat with recombinant human Epo (rHuEpo). In normal rats, Epo caused a dose-dependent increase in both reticulocyte and platelet numbers, the reticulocyte response preceding that of platelets. Withdrawal of Epo resulted in reticulocytes and platelets returning to control levels. [75Se]-selenomethionine incorporation into platelets was also enhanced in response to Epo. Chronic daily administration of rHuEpo resulted in steady state erythrocyte levels after 12 to 14 days, which were elevated 20% above controls. Attainment of this steady state was associated with both reticulocytes and platelets returning to control levels despite continued administration of Epo, an effect not associated with a change in the half-life of circulating Epo. In polycythemic rats a platelet response was observed before an effect on reticulocytes. Erythropoietin caused a 2.4-fold increase in the frequency of small acetylcholinesterase-positive cells within 24 hours, and increased the mean megakaryocyte diameter within 48 hours. Furthermore, the [3H]-thymidine labeling index of megakaryocytes from rats treated for 24 hours with rHuEpo was increased for all stages of megakaryocyte maturation. These results support the proposal of an effect of Epo on rat megakaryocytes causing increased platelet production. 相似文献
125.
W E. Gillies FRACS FRACO FRCS Anne MV Brooks MD PhD FRACS FRACO FRACP 《Clinical & experimental ophthalmology》1996,24(2):111-115
Background: Since the introduction of carbonic anhydrase inhibitors, a topical preparation has been sought to avoid the complications of systemic medication while retaining the effect of lowering intraocular pressure. Recently, a topical carbonic anhydrase inhibitor, MK-507, has been found superior to others and introduced for multicentre clinical trial.
Patients and methods: As part of an international rnulticentre trial, we compared MK-507 with beta blockers for one year in 20 patients with raised intraocular pressure, both as monotherapy and in combination.
Results: Twelve patients with a mean peak pressure of 31.9 ± 6.8 mmHg (range, 22 to 49 mmHg) off all medication received MK-507. After two weeks, mean peak pressure was 24.7 ± 6.1 mmHg (range, 14 to 41 mmHg) — a 22.6% fall in pressure. Six of these patients had a mean peak pressure of 27.8 ± 6.4 mmHg (range, 21 to 41 mmHg), a fall of 19.2% from day one and were given timolol as add-on therapy. This resulted in a fall to 19.1 ± 2.8 (range, 15 to 24 mmHg) at year one, a fall of 31.3% after add-on. Four patients on timolol and four on betaxolol gave similar falls in pressure with an additional fall when MK-507 was used as add-on therapy.
Conclusions: MK-507 demonstrated its effectiveness as an ocular hypotensive agent in this trial of patients with an unusually high rise in pressure. It showed a hypotensive effect roughly equivalent to beta blockers. It is likely that either a topical carbonic anhydrase inhibitor or a cardioselective beta blocker will be the medication of first choice in newly diagnosed glaucoma. 相似文献
Patients and methods: As part of an international rnulticentre trial, we compared MK-507 with beta blockers for one year in 20 patients with raised intraocular pressure, both as monotherapy and in combination.
Results: Twelve patients with a mean peak pressure of 31.9 ± 6.8 mmHg (range, 22 to 49 mmHg) off all medication received MK-507. After two weeks, mean peak pressure was 24.7 ± 6.1 mmHg (range, 14 to 41 mmHg) — a 22.6% fall in pressure. Six of these patients had a mean peak pressure of 27.8 ± 6.4 mmHg (range, 21 to 41 mmHg), a fall of 19.2% from day one and were given timolol as add-on therapy. This resulted in a fall to 19.1 ± 2.8 (range, 15 to 24 mmHg) at year one, a fall of 31.3% after add-on. Four patients on timolol and four on betaxolol gave similar falls in pressure with an additional fall when MK-507 was used as add-on therapy.
Conclusions: MK-507 demonstrated its effectiveness as an ocular hypotensive agent in this trial of patients with an unusually high rise in pressure. It showed a hypotensive effect roughly equivalent to beta blockers. It is likely that either a topical carbonic anhydrase inhibitor or a cardioselective beta blocker will be the medication of first choice in newly diagnosed glaucoma. 相似文献
126.
Ploos van Amstel HK; Huisman MV; Reitsma PH; Wouter ten Cate J; Bertina RM 《Blood》1989,73(2):479-483
Familial thrombophilia, the hereditary predisposition to venous thromboembolic disease, is associated with a protein S deficiency in approximately 8% of the cases. Laboratory measurements of total protein S antigen in affected families have indicated that heterozygotes, ie, individuals carrying both a normal and a defective protein S gene, are severely at risk of developing venous thrombosis at a young age. The recent isolation of protein S cDNA has enabled us to start a search for genetic defects in the protein S gene of heterozygotes. Using Southern blotting on probands of six unrelated families with hereditary protein S deficiency, one proband was found to have a grossly abnormal gene pattern. The abnormality appears to involve at least the deletion of the middle portion of the protein S coding sequence. Family analysis showed that the defect cosegregates with the protein S deficiency. These data agree with the notion that hereditary thrombophilia associated with protein S deficiency is indeed directly the result of a defect in the protein S gene. 相似文献
127.
Influence of low and high frequency inputs on spike timing in visual cortical neurons 总被引:6,自引:2,他引:4
Cortical neurons in vivo respond to sensory stimuli with the generation of
action potentials that can show a high degree of variability in both their
number and timing with repeated presentations as wells as, on occasion, a
high degree of synchronization with other cortical neurons, including in
the gamma frequency range of 30-70 Hz. Here we examined whether or not this
variability may arise from the intrinsic mechanisms of action potential
generation in cortical regular spiking, fast spiking and intrinsic
burst-generating neurons maintained in vitro. For this purpose, we
performed intracellular recordings in slices of ferret visual cortex and
activated these cells with the intracellular injection of various current
waveforms. Some of these waveforms were derived from barrages of
postsynaptic potentials evoked by visual stimulation recorded in vivo;
others were artificially created and contained various amounts of gamma
range fluctuations; finally, others consisted of swept-sinewave current
(ZAP current) functions. Using such stimuli, we found that, as expected
given the resistive and capacitive properties of cortical neurons, low
frequencies have a larger effect on the membrane potential of cortical
neurons than do higher frequencies. However, increasing the amount of gamma
range fluctuations in a stimulus leads to more precise timing of action
potentials. This suggests that different frequencies play different roles,
low frequencies being efficient for depolarizing cells with high
frequencies increasing the precision of action potential timing. In
parallel to increases in temporal precision, the addition of higher
frequency components increases the range of interspike intervals present in
the action potential discharge. These results suggest that higher frequency
components such as gamma range fluctuations may facilitate the generation
of action potentials with a high temporal precision while at the same time
exhibiting a high degree of variability in interspike intervals on single
trials. This temporal precision may facilitate the use of temporal codes or
the generation of precise synchronization for the transmission and analysis
of information within cortical networks.
相似文献
128.
129.
Arunava Kali MV Pravin Charles Mariya Joseph Noyal Umadevi Sivaraman Shailesh Kumar Joshy M Easow 《The Australasian medical journal》2013,6(8):387-391
Background
Candida species are emerging as a potentially pathogenic fungus in patients with broncho-pulmonary diseases. The synergistic growth promoting association of Candida and Mycobacterium tuberculosis has raised increased concern for studying the various Candida spp . and its significance in pulmonary tuberculosis patients during current years.Aims
This study was undertaken with the objective of discovering the prevalence of co-infection caused by different Candida species in patients with pulmonary tuberculosis.Method
A total of 75 patients with pulmonary tuberculosis diagnosed by sputum Ziehl-Neelsen staining were included in the study. Candida co-infection was confirmed using the Kahanpaa et al. criteria. Candida species were identified using gram stain morphology, germ tube formation, morphology on cornmeal agar with Tween-80, sugar fermentation tests and HiCrome Candida Agar.Results
Candida co-infection was observed in 30 (40%) of patients with pulmonary tuberculosis. Candida albicans was the most common isolate observed in 50% of the patients with co-infection, followed by C. tropicalis (20%) and C. glabrata (20%). Candida co-infection was found in 62.5% of female patients, while it was observed in only 29.4% of the male patients (P value 0.0133). Mean ± SD age of the patients with C. glabrata infection was 65.83 ± 3.19, while the mean ± SD age of the patients with other Candida infections was 43.25 ± 20.44 (P value 0.0138).Conclusion
Many patients with pulmonary tuberculosis have co-infection with Candida spp. The prevalence of non-albicans Candida species is increasing and may be associated with inadequate response to anti-tubercular drugs. C. glabrata infection has a strong association with old age. 相似文献130.
F?de la?PortillaEmail author ML?Reyes-Díaz MV?Maestre RM?Jiménez-Rodríguez AM?García-Cabrera JM?Vázquez-Monchul JM?Díaz-Pavón FC?Padillo-Ruiz 《International journal of colorectal disease》2017,32(3):437-440