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441.
442.
OBJECTIVE: To evaluate the usefulness of fine needle aspiration (FNA) study of lymph nodes in HIV-positive patients. STUDY DESIGN: The study was conducted at Kasturba Medical College, Mangalore, India. Samples from lymph nodes of 48 HIV-positive patients were taken and air dried, and wet smears were made. After staining with routine cytologic stains and special stains, detailed cytomorphologic study was conducted. RESULTS: Tuberculosis accounted for nearly half (48%) the cases,followed by HIV lymphadenitis (36%), lymphoma (10%), suppurative lymphadenitis (2%), Mycobacterium avium-intracellulare lymphadenitis (2%) and metastases (2%), in descending order of their frequency. A suppurative picture, which was found in 13% of cases of tuberculous lymphadenitis in AIDS patients, occasionally was misleading without the help of acid fast bacilli stain. CONCLUSION: FNA is a useful tool in the diagnosis of lymphadenopathy in HIV-positive patients provided that proper safety measures are taken to avoid contracting the infection.  相似文献   
443.
Gastric ulcers were induced in normal/NIDDM rats by various physical (2 hr cold restraint stress and 4 hr pylorus ligation) and chemical agents (ethanol, 1 ml/200 g, oral, 1 hr before; aspirin, 200 mg/kg, oral, 4 hr) and duodenal ulcers were induced by cysteamine (40 mg/200 g). Ulcer healing activity was studied in gastric ulcers induced by acetic acid (50%) and HCI (0.6 M). The result indicated that in both, normal and NIDDM rats, B. monniera extract (BME, 20-100 mg/kg) did not show any significant effect on blood glucose level, while A. indica (AIE, 250-1000 mg/kg) significantly decreased it. However, both BME (50 mg/kg) and AIE (500 mg/kg) showed significant anti-ulcer and ulcer-healing activities in normal and NIDDM rats. Further, the present results also indicated that the ulcer protective effects of BME was more pronounced in non-diabetic, while that of AIE was more in NIDDM rats. The anti-ulcer and ulcer-healing activities of BME and AIE may be due to their effects on various mucosal offensive and defensive factors, and correction of blood sugar level by AIE may help to have more ulcer protective effect in NIDDM rats.  相似文献   
444.
Previous studies have shown that estrogen plays an important role in sex change of protogynous honeycomb grouper, and that the treatments with aromatase inhibitor (AI) cause estrogen depletion and complete sex inversion of pre-spawning females into functional males. In the present study, we examined whether AI causes sex inversion of sexually immature females. Female honeycomb groupers were implanted with various doses of Fadrozole (0, 100, 500 and 1000 microg/fish) in the non-breeding season, and resultant changes in the gonadal structures and the plasma levels of sex steroid hormones (estradiol-17 beta, E2; testosterone, T; 11-ketotestosterone, 11-KT) were examined three months after implantation. Vehicle-implanted groups did not change sex, while 100 and 500 microg AI-implanted groups had turned into transitionals with intersex gonad. In contrast, the highest dose receiving group exhibited both transitional and male phases. Transitional phase gonad had atretic oocytes and spermatogenic germ cells at the late stages of spermatogenesis, while male phase testis contained spermatozoa accumulated in the seminiferous tubules. All males released sperm upon slight pressure on the abdomen. In the AI-implanted fish, plasma levels of E2 decreased in a dose-dependent manner, while the levels of 11-KT were high in the highest dose receiving group. Present results suggest that estrogen plays an important role in sex change of protogynous honeycomb grouper, and that treatments with AI potentially inhibits endogenous E2 production in vivo, causing oocyte degeneration and subsequently the sex inversion from female to male. The Fadrozole could be an important tool for manipulating the sex of hermaphrodite fishes.  相似文献   
445.
Atrial fibrillation (AF) is the most commonly encountered sustained clinical arrhythmia with an estimated 2.3 million cases in the US (2001). A(1) adenosine receptor agonists can slow the electrical impulse propagation through the atrioventricular (AV) node (i.e., negative dromotropic effect) resulting in prolongation of the stimulus-to-His bundle (S-H) interval to potentially reduce ventricular rate. Compounds that are full agonists of the A(1) adenosine receptor can cause high grade AV block. Therefore, it is envisioned that a compound that is a partial agonist of the A(1) adenosine receptor could avoid this deleterious effect. 5(') Phenyl sulfides (e.g., 17, EC(50)=1.26 microM) and phenyl ethers (e.g., 28, EC(50)=0.2 microM) are partial agonists with respect to their AV nodal effects in guinea pig isolated hearts. Additional affinity, GTPgammaS binding data suggesting partial activity of the A(1) adenosine receptor, and PK results for 5(') modified adenosine derivatives are shown.  相似文献   
446.
The protogynous hermaphrodite fish change sex from female to male at the certain stages of life cycle. The endocrine mechanisms involved in gonadal restructuring throughout protogynous sex change are not clearly understood. In the present study, we implanted maturing female honeycomb groupers with nonsteroidal aromatase inhibitor (AI), Fadrozole (0, 1, and 10 mg/fish) and examined changes in gonadal structures and serum levels of sex steroid hormones 2(1/2) months after implantation. The ovaries of control females had oocytes undergoing active vitellogenesis, whereas AI caused females to develop into functional males. These males had testes, which were indistinguishable in structure from those of normal males, but bigger in size, and completed all stages of spermatogenesis including accumulation of large amount of sperm in the seminiferous tubules. AI significantly reduced the serum levels of estradiol-17beta (E2) and increased levels of testosterone (T), 11-ketotestosterone (11-KT), and 17alpha, 20beta-dihydroxy-4-pregnen-3-one (DHP). Further, AI suppressed in vitro production of E2, and stimulated the production of T and 11-KT in the ovarian fragments of mature female. In the honeycomb grouper, suppression of both in vitro and in vivo production of E2 and degeneration of oocytes by AI suggests that AI induces complete sex change through inhibition of estrogen biosynthesis, and perhaps, subsequent induction of androgen function.  相似文献   
447.
The response of the fetal rat Type II pneumocyte (FTIIP), the stem cell of the alveolar epithelium, to hyperoxia would be helpful to understand the effects of oxygen-induced injury to the developing lung. Our goals were to evaluate the effect of antioxidants (AO) on apoptosis and release of cytokines in freshly isolated FTIIP (day-19) in the presence of 95% O2 and/or nitric oxide (NO). There was increased apoptosis in FTIIP exposed to hyperoxia alone and in combination with NO; this was significantly attenuated (p < 0.01) in the presence of 3 AO, namely grape seed proanthocyanidin extract (GSPE), superoxide dismutase (SOD) and catalase. The anti-inflammatory cytokine IL-10 has been shown to have a role in ameliorating tissue damage owing to persistent inflammation. The release of IL-10 was significantly decreased (p < 0.01) in the presence of GSPE and catalase, compared to control. Addition of SOD led to increased IL-10 compared to GSPE or catalase (p < 0.01) or the combination of GSPE + SOD + catalase (p < or = 0.01). Thus, in our in vitro model of hyperoxic and NO mediated injury to FTIIP, protection from apoptotic cell death with the addition of AO was associated with varying levels of IL-10 release. Our data suggest that the use of SOD and/or IL-10 may decrease hyperoxic lung injury by decreasing apoptosis. Further studies are needed to understand the mode of protection from catalase and GSPE.  相似文献   
448.
Brugia malayi microfilarial excretory-secretory (mf ES) and phosphate buffer saline soluble (mf S) antigens were fractionated by fast protein liquid chromatography (FPLC) on superdex 200 HR 10/30 gel filtration column. The active antigen fractions were identified and explored in comparison with whole mf ES and mf S antigens to detect filarial IgG antibodies in different groups viz microfilaraemics, acute, chronic and occult filarial cases of Wuchereria bancrofti infection and endemic and non-endemic normals. One of the fractions of mf ES antigen (ESF-6) and two fractions of mf S antigen (SF-2 & 3) were identified to be useful to detect filarial antibodies. A pooled preparation of these antigen fractions gave a sensitivity of 86.6% (for microfilaraemic cases) and a specificity of 95% to detect filarial IgG antibodies by indirect ELISA. The pooled FPLC purified mf antigens also showed 55-88% of cases of different grades of clinical filariasis and 65% of tropical pulmonary eosinophilia cases as positive for filarial antibodies. The pooled FPLC purified B. malayi mf antigens with higher specificity are preferable to whole mf ES and mf S antigens to detect active filarial infection in microfilaraemia and as well in different clinical entities of bancroftian filariasis.  相似文献   
449.
Conformational features of reduced and disulfide intact hen egg white lysozyme in aqueous 1,4-dioxane and 3-chloro-1, 2-propanediol solutions have been examined using circular dichroism and fluorescence spectroscopy. We find that in presence of 1, 4-dioxane, reduced lysozyme assumes a relatively compact conformational form with secondary structure closer to native state and no tertiary structure as judged by peptide and aromatic CD spectra and ANS binding studies monitored by fluorescence. Further, in presence of 40% (v/v) 3-chloro-1, 2-propanediol, disulfide intact lysozyme (DI-lysozyme) assumes a conformational form with native like secondary structure and no tertiary structure akin to a molten globule state. We correlate our results to kinetic hydrogen- deuterium exchange NMR results of the refolding of lysozyme available in literature and suggest that the conformational forms observed in our study could be models for kinetic intermediates in the refolding of lysozyme.  相似文献   
450.
The prevalence of obesity has been rising alarmingly and it has now become a global concern causing an enormous economic burden on the health care system. Obesity is generally linked to complications in lipid metabolism and oxidative stress. The aim of the present study was to investigate the effect of rosuvastatin (10 mg/kg, po) on obesity-induced oxidative stress in high fat-fed Wistar rats. Oral administration of rosuvastatin (10 mg/kg) for 21 days along with high fat diet brought about significant elevation in serum high density lipoprotein and cardiac antioxidant enzymes levels (superoxide dismutase, catalase, glutathione, glutathione peroxidase, glutathione peroxidase-, glutathione reductase- and glutathione-S-transferase) while decreasing in serum lactate dehydrogenase, apolipoprotein-B, lipids (triglycerides, total cholesterol, low density lipoprotein-cholesterol, very low density lipoprotein-cholesterol and atherogenic index) and cardiac thiobarbituric acid reactive substances levels. The results were comparable with orlistat, a standard antiobesity drug. These preliminary results for the first time demonstrate that administration of rosuvastatin can be beneficial for the suppression of obesity-induced oxidative stress and dyslipidemia in high fat-fed Wistar rats.  相似文献   
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