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71.
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Lysin is a 16kDa acrosomal protein used by abalone sperm to create a hole in the egg vitelline envelope (VE). The interaction of lysin with the VE is species-selective and is one step in the multistep fertilization process that restricts heterospecific (cross-species) fertilization. For this reason, the evolution of lysin could play a role in establishing prezygotic reproductive isolation between species. Previously, we sequenced sperm lysin cDNAs from seven California abalone species and showed that positive Darwinian selection promotes their divergence. In this paper an additional 13 lysin sequences are presented representing species from Japan, Taiwan, Australia, New Zealand, South Africa, and Europe. The total of 20 sequences represents the most extensive analysis of a fertilization protein to date. The phylogenetic analysis divides the sequences into two major clades, one composed of species from the northern Pacific (California and Japan) and the other composed of species from other parts of the world. Analysis of nucleotide substitution demonstrates that positive selection is a general process in the evolution of this fertilization protein. Analysis of nucleotide and codon usage bias shows that neither parameter can account for the robust data supporting positive selection. The selection pressure responsible for the positive selection on lysin remains unknown.  相似文献   
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The most common form of glomerular disease seen in association with hepatitis C virus (HCV) infection is membranoproliferative glomerulonephritis, with or without associated cryoglobulinemia. This study examines four cases of fibrillary glomerulonephritis and two cases of immunotactoid glomerulopathy in association with HCV infection. Findings at presentation included proteinuria, renal insufficiency, and hematuria. Renal biopsy revealed a membranoproliferative pattern of glomerular disease in five cases, and a membranous glomerulopathy with mesangial proliferative features in one. On immunofluorescence, all cases stained with IgG and C3. Electron microscopy revealed fibrils of the expected diameter, 16 to 28 nm in fibrillary glomerulonephritis and 33 to 45 nm in immunotactoid glomerulopathy. In only one case were cryoglobulins detected (at low titer and on only one of three assays). Antiviral therapy was not given in any of the six cases. Outcomes were mixed, with progression to renal failure occurring in two patients and persistent proteinuria with stable or improved renal function in three. Follow-up is not available on the sixth case. Both fibrillary glomerulonephritis and immunotactoid glomerulopathy have features that overlap with cryoglobulinemic glomerulonephritis. The relatedness of these three entities in a subset of patients with HCV infection suggests a common pathogenic mechanism of glomerular deposition of organized deposits.  相似文献   
75.
The aim of the work was investigation of both efficacy of sulpiride, atypical neuroleptic drug with pronounced antidepressive activity, and its influence on central nervous system. The study was performed in the course of prophylactic treatment of migraine using contingent negative variation (CNV) index. It is demonstrated that sulpiride is effective in prophylactic treatment of migraine complicated with psychologic disorders and autonomic dysfunctions. Such effect may be caused by the drug's influence on depression, anxiety, autonomic symptoms, tension-type headaches. This conclusion was confirmed by CNV data, change of which after sulpiride administration have indicated normalization of mental performance and increase of active adaptive abilities.  相似文献   
76.
The new method for microbiological analysis of blood in patients with pyoseptic infections is based on separate inoculations of plasma, erythrocyte mass, and leukocyte layer in nutrient medium providing conditions for growth of a wide spectrum of aerobes and obligate anaerobes. The method in general ensures a more rapid result and permits differentiation between true and false-positive bacteremia and between stages of septic process (bacteremia and septicemia).  相似文献   
77.
Phytochemicals such as indole-3-carbinol (I3C) and sulforaphane are components of cruciferous vegetables which exhibit antitumorigenic activity associated with altered carcinogen metabolism and detoxification. Diindolylmethane (DIM) is a major acid-catalyzed metabolite of I3C formed in the gut that binds to the aryl hydrocarbon receptor (AhR) and treatment of MCF-7 human breast cancer cells with 10-50 microM DIM resulted in rapid formation of the nuclear AhR complex and induction of CYP1A1 gene expression was observed at concentrations >50 microM. Previous studies have demonstrated that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a high affinity AhR ligand, inhibits 17beta-estradiol (E2)-induced responses in MCF-7 cells and growth of E2-dependent 7,12-dimethylbenzanthracene (DMBA)-induced mammary tumors in female Sprague-Dawley rats. Results of this study show that like TCDD, DIM inhibits E2-induced proliferation of MCF-7 cells, reporter gene activity in cells transiently transfected with an E2-responsive plasmid (containing a frog vitellogenin A2 gene promoter insert) and down-regulates the nuclear estrogen receptor. Moreover, DIM (5 mg/kg every other day) also inhibits DMBA-induced mammary tumor growth in Sprague-Dawley rats and this was not accompanied by induction of hepatic CYP1A1-dependent activity. Thus, DIM represents a new class of relatively non-toxic AhR-based antiestrogens that inhibit E2-dependent tumor growth in rodents and current studies are focused on development of analogs for clinical treatment of breast cancer.  相似文献   
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SCOPE OF THE STUDY: We studied the possibility to examine position and determination of IOL and capsular bag supporting ring. PATIENTS AND METHODS: We showed in ten human eyes the identification of capsular bag supporting ring (PMMA, 12,5 mm open diameter) and intraocular lenses (IOL, 13,5 mm diameter) and haptics by ultrasound biomicroscopy in radar and limbus parallel scans 12 to 18 months post operation. RESULTS: Both alloplastic implantates show typical sceems of reflection and could be differentiated by ultrasoundbiomicroscopy. In eyes with zonulolysis up to 6 hours a good centration of capsular bag supporting ring and IOL had been seen, with more zonulolyses a slight subluxation could been shown. CONCLUSION: Ultrasound biomicroscopy is a good method to determine the position of intraocular lens and capsular bag supporting ring.  相似文献   
80.
The authors submit results of treatment of patients having suffered from postherpetic pain syndrome (herpetic ganglionitis of the cervical, thoracic, lumbosacral localization, postherpetic intercostal neuralgia, ganglionitis of the trigeminal nerve). In viral diseases, amizone has marked analgetic, antiinflammatory, and immunomodulating effects. The drug is well tolerated by patients, is not associated with side effects under prescribed doses (0.25-0.75 as one dose on a three- or four-times daily schedule during the course of treatment lasting three or four weeks). The drug preparation in question is less effective in the treatment of chronic recurring post-therapeutic intercostal neuralgias, radiculalgia.  相似文献   
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