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91.
92.
NE Basci S Hanioglu-Kargi H Soysal A Bozkurt SO Kayaalp 《Canadian Metallurgical Quarterly》1997,15(5):663-666
This unusual pathology has not been described in the medical literature of the last ten years. A 39-year-old patient, affected by unilateral cryptorchidism, on the right side, and congenital inguinal hernia, reached the operating theatre suffering from occlusive intestinal syndrome, due to a clogged hernial sac. This clog was caused by a retracting testicle which in turn stopped the ileal ansa from slipping back in to the peritoneum. Through this case we can underline the excursus of such pathology, which isn't very frequent in the adult but can, nevertheless create a fairly serious pathology, often leading to neoplan. 相似文献
93.
94.
DJ Kempf HL Sham KC Marsh CA Flentge D Betebenner BE Green E McDonald S Vasavanonda A Saldivar NE Wideburg WM Kati L Ruiz C Zhao L Fino J Patterson A Molla JJ Plattner DW Norbeck 《Canadian Metallurgical Quarterly》1998,41(4):602-617
The structure-activity studies leading to the potent and clinically efficacious HIV protease inhibitor ritonavir are described. Beginning with the moderately potent and orally bioavailable inhibitor A-80987, systematic investigation of peripheral (P3 and P2') heterocyclic groups designed to decrease the rate of hepatic metabolism provided analogues with improved pharmacokinetic properties after oral dosing in rats. Replacement of pyridyl groups with thiazoles provided increased chemical stability toward oxidation while maintaining sufficient aqueous solubility for oral absorption. Optimization of hydrophobic interactions with the HIV protease active site produced ritonavir, with excellent in vitro potency (EC50 = 0.02 microM) and high and sustained plasma concentrations after oral administration in four species. Details of the discovery and preclinical development of ritonavir are described. 相似文献
95.
NE Ordian AI Va?do VV Rakitskaia NV Shiriaeva FI Pro?mina NG Lopatina VG Shaliapina 《Canadian Metallurgical Quarterly》1998,125(4):443-445
Although behavioral and neuropsychological data regarding the existence of images for odors are inconclusive, reconsideration of earlier EEG work provides reasonably clear evidence for an inner nose. However, further EEG studies and neuroimaging data seem essential for conclusive demonstration of an inner nose. 相似文献
96.
GD Jackson SR Williams RO Weller N van Bruggen NE Preece SC Williams WH Butler JS Duncan 《Canadian Metallurgical Quarterly》1994,18(1):57-66
Previous research has indicated that individual foods or beverages are ingested independently and do not produce adjustments to the intake of other constituents in the diet (de Castro, 1993; Wilson, 1991). In order to eliminate time of day as a potential contaminant, the present study investigated the accommodation of foods and beverages into the amount ingested at large evening meals only. Adults (n = 601) were paid to maintain detailed diaries of the timings, quantities and preparation techniques of everything they ingested for seven consecutive days. With the exceptions of soup, beef and chicken, 12 out of 15 types of drinks or foods were found to add to the total calories ingested in evening meals without displacing calories ingested in other forms, while ingestion of non-caloric diet sodas was not associated with differences in intake. The fat and protein, but not carbohydrate, contents of the items correlated with a measure of the satiating properties of the particular food or beverage, namely the correlation between the amount ingested of the particular type and the amounts of other nutrients ingested in the meal. The results confirm that intake at a meal is quite elastic and can be significantly influenced by the presence or absence of particular components of the meal and their constituents. 相似文献
97.
PA Huber Y Gao ID Fraser O Copeland M EL-Mezgueldi DA Slatter NE Keane SB Marston BA Levine 《Canadian Metallurgical Quarterly》1998,37(8):2314-2326
We have used isotope-edited nuclear magnetic resonance spectroscopy, binding studies, and ATPase activity assays to investigate the interaction with F-actin of the 10 kDa C-terminal 658C fragment of chicken gizzard caldesmon and two site-directed mutants of this fragment. Simultaneous dual-sited contacts with F-actin are observed for the segments of the 658C sequence flanking tryptophan residues 692 and 722. Competition experiments showed that both 658C contacts with actin are displaced by substoichiometric concentrations of the short inhibitory region of troponin-I indicative of different binding sites on actin for these regions of troponin-I and caldesmon. Substitution of caldesmon serine-702 by aspartic acid within the spacer region linking the two actin contacts of 658C led to weaker binding but with retention of equivalent affinity for each interaction site. Differential binding affinity of the two sites was achieved by replacement of the sequence Glu691-Trp-Leu-Thr-Lys-Thr696 by Pro-Gly-His-Tyr-Asn-Asn. Consistent with these data, the concentration of this Cg1 mutant required to achieve 50% inhibition of actin-tropomyosin-activated myosin ATPase was 4-fold greater than found for the 658C fragment. Although calmodulin binding to Cg1 was observed, calmodulin proved ineffective in relieving the inhibition induced by the binding of this mutant to actin. These results are discussed in light of the actin contacts which are involved in the inhibitory activity possessed by different regions of the C-terminus of caldesmon. 相似文献
98.
ES Pizer C Jackisch FD Wood GR Pasternack NE Davidson FP Kuhajda 《Canadian Metallurgical Quarterly》1996,56(12):2745-2747
One of the key limiting factors in the treatment of advanced stage human epithelial malignancies is the lack of new, selective molecular targets for antineoplastic therapy. A substantial subset of human breast, ovarian, endometrial, colorectal, and prostatic cancers express elevated levels of fatty acid synthase, the major enzyme required for endogenous fatty acid biosynthesis, and carcinoma lines are growth inhibited by cerulenin, a noncompetitive inhibitor of fatty acid synthase. We have shown previously that the difference in fatty acid biosynthesis between cancer and normal cells is an exploitable target for metabolic inhibitors in the in vitro setting and in vivo in a human ovarian carcinoma xenograft in nude mice. Here, we report that cerulenin treatment of human breast cancer cells inhibits fatty acid synthesis within 6 h after exposure, that loss of clonogenic capacity occurs within the same interval, and that DNA fragmentation and morphological changes characteristic of apoptosis ensue. 相似文献
99.
H Openshaw NE Slatkin AS Stein DR Hinton SJ Forman 《Canadian Metallurgical Quarterly》1996,78(9):1899-1905
BACKGROUND: Peripheral nerve toxicity has been reported but is not a commonly recognized complication of high dose cytosine arabinoside (HDAC) therapy. This study was undertaken to estimate the prevalence and describe the clinical spectrum of acute polyneuropathy associated with HDAC therapy for leukemia. METHODS: Records of 153 acute leukemia patients who received 194 courses of HDAC at the City of Hope were reviewed for evidence of severe peripheral neuropathy with onset 2-3 weeks after HDAC therapy. RESULTS: Two patients were identified who developed motor disability 2-3 weeks after HDAC therapy, and the disability progressed in a monophasic course to quadriparesis. There was neurophysiologic evidence of peripheral nerve demyelination with slowed nerve conduction velocities and conduction block. One patient who was autopsied had demyelination identified in luxol-fast blue sections of peripheral nerve (with Bielschowsky-stained sections showing intact peripheral nerve axons). There were foamy macrophages in the peripheral nerve but no chronic inflammatory cells. For comparison, data from these two patients were combined with those from four published case reports of polyneuropathy associated with HDAC therapy. Quadriparesis occurred in five of six cases with the need for ventilatory support in four. Cerebrospinal fluid protein was elevated in five of six cases. Etiologic evidence incriminating HDAC included simultaneous cerebellar signs in two of six cases and a narrow interval of clinical onset after HDAC therapy. CONCLUSIONS: Demyelinating polyneuropathy occurs in approximately 1% of HDAC courses and produces severe motor disability. HDAC immunosuppression could trigger an immune-mediated neuropathy; alternatively, a direct neurotoxic effect of HDAC on Schwann cells is also an etiologic possibility. 相似文献
100.
MK Jain MD Layne M Watanabe MT Chin MW Feinberg NE Sibinga CM Hsieh SF Yet DL Stemple ME Lee 《Canadian Metallurgical Quarterly》1998,273(11):5993-5996
The change in vascular smooth muscle cells (SMC) from a differentiated to a dedifferentiated state is the critical phenotypic response that promotes occlusive arteriosclerotic disease. Despite its importance, research into molecular mechanisms regulating smooth muscle differentiation has been hindered by the lack of an in vitro cell differentiation system. We identified culture conditions that promote efficient differentiation of Monc-1 pluripotent neural crest cells into SMC. Exclusive Monc-1 to SMC differentiation was indicated by cellular morphology and time-dependent induction of the SMC markers smooth muscle alpha-actin, smooth muscle myosin heavy chain, calponin, SM22alpha, and APEG-1. The activity of the SM22alpha promoter was low in Monc-1 cells. Differentiation of these cells into SMC caused a 20-30-fold increase in the activity of the wild-type SM22alpha promoter and that of a hybrid promoter containing three copies of the CArG element. By gel mobility shift analysis, we identified new DNA-protein complexes in nuclear extracts prepared from differentiated Monc-1 cells. One of the new complexes contained serum response factor. This Monc-1 to SMC model should facilitate the identification of nodal regulators of smooth muscle development and differentiation. 相似文献