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51.
Microparticles composed of each of four enzymically synthesized homopolynucleotides and the same lysine-rich proteinoid have been found to influence the condensation of the AMP-anhydrides of each of four amino acids. The conditions of preparation of the particles and other variables of the experiments control the types of reaction. When a specified set of conditions was identified empirically, the incorporation favored the amino acids whose present-day codons are related to the homopolynucleotide in the particle.  相似文献   
52.
Background Paraaortic lymph node metastasis is an important prognostic factor in gynecologic malignancy. However, paraaortic lymph node dissection (PAND) is not done routinely in Japan because of the difficulty of the procedure and the high incidence of complications. We performed PAND in 217 patients in a 7-year period. In the present study, we focused on the occurrence of postoperative ileus in patients who underwent PAND.Methods Two hundred and seventeen patients with malignant gynecologic tumors were operated on at our hospital between January 1995 and August 2001. All patients underwent PAND and pelvic lymph node dissection (114 patients had a radical hysterectomy; 103 patients had a simple hysterectomy). We evaluated postoperative ileus in three categories of severity.Results The average operation time and blood loss in the patients with radical and simple hysterectomies with PAND were 317 min and 1158 g, and 246 min and 820 g, respectively. The incidence of postoperative ileus was 12.9% (28/217). Although there were no significant differences in the occurrence of ileus between patients with the radical and simple hysterectomies (10.5% vs 15.5%), the incidence of ileus in patients with radical hysterectomy with PAND was significantly higher than that in a control group of patients with radical hysterectomy without PAND (10.5% vs 3.4%). However, in the PAND patients the postoperative ileus was mostly mild or moderate (10 mild cases, 15 moderate cases, and 3 severe cases). Severe ileus occurred in three patients with radical hysterectomy with PAND. Although a repeat operation was necessary for two of these three patients with severe ileus, they recovered uneventfully.Conclusion PAND for malignant gynecologic tumors is a feasible and safe operative procedure, with a low incidence of postoperative ileus.  相似文献   
53.
Galanin-like peptide (GALP) has been recently isolated from the porcine hypothalamus. The GALP mRNA is restricted to neurons in the hypothalamic arcuate nucleus (Arc) and pituicytes in the posterior pituitary gland (PP), but physiological functions of the GALP remains unclear in both areas. We examined the effects of acute and chronic inflammatory stresses on the GALP mRNA levels in the rat Arc using in situ hybridization histochemistry. Intraperitoneal (i.p.) injection of bacterial endotoxin lipopolysaccharide (LPS) caused a marked increase of the GALP mRNA levels in the Arc. The effects of i.p. injection of LPS on the GALP mRNA levels in the Arc were significantly attenuated by pretreatment with i.p. injection of indomethacin cyclooxygenase inhibitor. Adjuvant arthritis caused by subcutaneous (s.c.) injection of heat-killed Mycobacterium butyricum as chronic inflammatory stress did not affect the GALP mRNA levels in the Arc, though the GALP mRNA levels in the pituicytes of the PP were markedly increased by two peaks at 12 h and 15 days after s.c. injection of heat-killed M. butyricum. Enzymeimmunoassay showed that the plasma concentration of GALP was not affected by these inflammatory stresses. These results suggest that acute inflammatory stress might be a potent stimulant to increase the GALP mRNA levels in the Arc of the rat via synthesis of prostaglandins.  相似文献   
54.
Estrogen deficiency causes reduction of bone mass and abnormal bone microarchitecture, consequently reducing bone strength. Human parathyroid hormone (hPTH) (1-34) increases bone mass and strength. To clarify the factors that determine the recovery of bone strength in the lumbar vertebrae of ovariectomized rats by intermittent hPTH administration, we analyzed the relationship between skeletal measurements and bone strength. Human PTH (1-34) administration resulted in recovery of cortical bone mineral content (BMC) and cortical bone area to sham the levels, but in resulted in a less pronounced recovery of trabecular BMC and no increase in the total cross-sectional area of the vertebral body. Of the three-dimensional (3D) trabecular bone parameters, hPTH (1-34) increased trabecular thickness (Tb.Th). The cortical shell area of L4, determined by histomorphometry, was also increased. In hPTH-treated rats, the only determinant of the compressive load of L5 was the cortical shell BMC, in the early recovery period (days 42–84). Our data suggest that increased cortical bone mass contributes more than trabecular bone mass and structure to the recovery of bone strength in response to hPTH therapy in the rat lumbar vertebral body after ovariectomy.  相似文献   
55.
We report a rare case of the development of various tumors over a 16-year period after renal transplantation. A 56-year-old woman underwent renal transplantation using a US kidney. Immunosuppressive treatment consisted of a triple regimen of methylprednisolone, azathioprine, and mizoribine. Left breast cancer was diagnosed 9 years after the renal transplantation, then colon cancers and meningeal epidermal meningioma were diagnosed, 10 years and 12 years post-transplant, respectively. During the investigations for the breast and colon cancers, a p53 gene mutation was detected. A deterioration of renal function was found 16 years after the transplant and graft biopsy confirmed chronic rejection. We suggest that the effects of the immunosuppressive drugs combined with the p53 gene abnormality accelerated tumor development in this patient.  相似文献   
56.
The role of interstitial cells of Cajal (ICC) in contractile activity of the gastrointestinal tract has been intensely studied. Among ICC present within various regions of the gastrointestinal tissue, ICC within the myenteric plexus (ICC-MY) and within the submuscular plexus (ICC-SMP) are regarded as the pacemaker. Action potentials initiated in ICC were suggested to propagate to adjacent smooth muscle cells and to induce the spontaneous activity. It was suggested that ACh-mediated contraction and nitric oxide-mediated relaxation were induced after these neuronal signals were transmitted to ICC and then to smooth muscle via the gap junction. This suggestion was based on the findings mainly in the esophagus, stomach, and small intestine by using ICC-deficient mice (W/W(V) and Sl/Sl(d)). In our studies, ICC-MY were shown to be closely associated with neuron-mediated contractile and relaxant responses and to be associated with neural reflexes for peristalsis, since ascending and descending reflexes were not seen in W/W(V) mice. In the distal colon of W/W(V) mice, in which ICC-MY and -IM were lost, these neural responses remained unchanged. It seems likely that ICC-MY and ICC-IM do not have any role in inducing these responses in the distal colon. It is concluded that the extent of association of ICC with the motility and the manner of the association vary from region to region in the gastrointestinal tract.  相似文献   
57.
We report a case of coexistence of lung cancer and tuberculoma in the same lesion. The component parts of lung cancer and tuberculoma were identified on the basis of morphology on high-resolution CT as well as enhancement patterns and time-attenuation curves by contrast-enhanced dynamic CT.  相似文献   
58.
The purpose of this study was to investigate the general application of a controlled-porosity osmotic pump tablet (OPT) utilizing (SBE)7m-beta-CD as both a solubilizer and an osmotic agent for drugs with varying physical properties. OPTs utilizing (SBE)7m-beta-CD were prepared for five poorly soluble and two highly water-soluble drugs. The Japanese Pharmacopoeia dissolution method was used to study the drug and (SBE)7m-beta-CD release from the OPTs. The drug concentration in the OPT core after the OPT was placed in the release medium for two hours was assayed gravimetrically and by HPLC. An appropriate composition ratio (ACR) of (SBE)7m-beta-CD to drug at which drug release from the OPT was complete and pH-independent within the physiological pH range of the GI tract was determined for each drug. The ACR values correlate to the drug concentration in the OPT core when the OPTs were placed in the release medium for two hours. The release profiles of prednisolone (a poorly water-soluble drug) and sodium chloride (a water-soluble compound) from the OPTs were almost the same as that of (SBE)7m-beta-CD. Also, the release rate of each drug per unit membrane surface area from the OPTs was similar, regardless of the differences in drug solubility. The present results confirmed that (SBE)7m-beta-CD serves as both a solubility modulator and as an osmotic pumping agent for OPTs, from which the release rate of both water-soluble and poorly water-soluble drugs can be controlled.  相似文献   
59.
In Japan, more than 10% of streptococcal toxic shock-like syndrome (TSLS) cases have been caused by Streptococcus pyogenes M3/T3 isolates since the first reported TSLS case in 1992. Most M3/T3 isolates from TSLS or severe invasive infection cases during 1992 to 2001 and those from noninvasive cases during this period are indistinguishable in pulsed-field gel electropherograms. The longest fragments of these recent isolates were 300 kb in size, whereas those of isolates recovered during or before 1973 were 260 kb in size. These 260- and 300-kb fragments hybridized to each other, suggesting the acquisition of an about 40-kb fragment by the recent isolates. The whole part of the acquired fragment was cloned from the first Japanese TSLS isolate, NIH1, and its nucleotide sequence was determined. The 41,796-bp fragment is temperate phage phiNIH1.1, containing a new superantigen gene speL near its right attachment site. The C-terminal part of the deduced amino acid sequence of speL has 48 and 46% similarity with well-characterized erythrogenic toxin SpeC and the most potent superantigen, SmeZ-2, respectively. None of 10 T3 isolates recovered during or before 1973 has speL, whereas all of 18 M3/T3 isolates recovered during or after 1992 and, surprisingly, Streptococcus equi subsp. equi ATCC 9527 do have this gene. Though plaques could not be obtained from phiNIH1.1, its DNA became detectable from the phage particle fraction upon mitomycin C induction, showing that this phage is not defective. A horizontal transfer of the phage carrying speL may explain the observed change in M3/T3 S. pyogenes isolates in Japan.  相似文献   
60.
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