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1.
In order to investigate possible differences in the reaction to hypoxic conditions between “red” and “white” skeletal muscle, cats were subjected to a 2 h period of either hemorrhagic shock or hind limb tourniquet ischemia, and the hypoxia induced changes were studied in the soleus and lateral gastrocnemius muscles. Muscle biopsies were analysed for ATP, CP, glucose, G 6–P and lactate. Using microelectrodes, the resting membrane potential was repeatedly measured. Both experimental models resulted in increased tissue lactate levels and a successive decrease in the membrane potential of both muscles studied. No reduction of the high energy phosphagen content (ATP+CP) occurred in any of the muscles during shock. The tourniquet ischemia resulted in a 40% reduction of the ATP+CP content in the soleus muscle, whereas in the gastrocnemius muscle no significant reduction occurred. A significant correlation was found between the tissue lactate content and the membrane potential under both conditions and in both muscles studied. It is concluded that “red” muscles are more susceptible to metabolic derangement than “white” muscles during total ischemia, whereas during hypovolemia “red” muscles appear to be protected from early hypoxic damage, probably due to a redistribution of skeletal muscle blood flow.  相似文献   

2.
Well‐defined glyco‐polyorganosiloxanes were synthesized by the Cu(I )‐catalyzed Huisgen 1,3‐dipolar cycloaddition reaction (often simply referred to as “click” chemistry). N‐propargylglycosylamines 2 and 4 were first synthesized from cellobiose ( 1 ) and xylogluco‐oligosaccharide XGOs 3 without protecting groups. The azide function was introduced into polydimethylsiloxanes [PDMS: 5 (MD′M) and 7 (M′DM′)] by azidolysis of the counterpart epoxy silicon with NaN3 to afford the mono‐azido 6 and di‐azido 8 derivatives, respectively. The coupling reaction took place in a hydro‐alcoholic medium in the presence of CuSO4/sodium ascorbate as catalyst. Only one compound, MD′M‐“click”‐XGO 12 showed good solubility in water with interesting surfactant properties.

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3.
Although familial forms of hypopituitarism are known, to our knowledge familial septooptic “dysplasia” in association with hypopituitarism has not been reported. We describe two first cousins with panhypopituitarism, one of whom had septooptic dysplasia. We discuss the possibility that septooptic dysplasia-hypopituitarism may be inherited as an autosomal dominant, or recessive, or multifactorial trait.  相似文献   

4.
Propargyl acrylate‐based functionalizable monolithic stationary phase (FMSP) for capillary electrochromatography, easily modifiable by alkyne–azide 1,3‐dipolar cycloaddition, is developed. Optimization of FMSP is focused on (i) physical properties: rigidity, stability, and pore size and (ii) the ease of capillary preparation and grafting. The effect of grafting is demonstrated on the separation of eleven polycyclic aromatic hydrocarbons (PAHs), three flavonols, and chlorpheniramine before and after derivatization. Two azides are synthesized: the first, cinnamyl azide increases the retention of PAHs and improves separation of flavonols, the second, 6‐azido‐6‐deoxy‐β‐cyclodextrin allows the chiral separation of warfarin, improves the efficiency of PAHs separation and increases retention of chlorpheniramine.  相似文献   

5.
Chordomas are relatively rare neoplasms occurring at both ends of a neuro axis. The majority follow an indolent course of multiple local recurrences, ultimately leading to the patient's death. Rare examples have been associated with sarcomatous components, usually resembling malignant fibrous histiocytoma, fibrosarcoma, or osteosarcoma. These tumors have followed a more aggressive course, with poor response to treatment and death following a relatively short time course. Cytologic material from a single case obtained by fine-needle aspiration revealed a high-grade malignancy composed of short atypical spindle cells containing modest amounts of granular cytoplasm. Physaliphorous cells were absent, and myxoid material was not a significant component of the smears. Rare polygonal cells with foamy cytoplasm were identified. Histologic study revealed a high-grade spindle-cell sarcoma in which were scattered small aggregates of vacuolated cells resembling physaliphorous cells. Anaplastic giant cells were present, and the overall appearance of the neoplasm resembled a malignant fibrous histiocytoma. Despite the radiographic appearance of a conventional chordoma in this case, the cytologic findings were indicative of a high-grade sarcoma consistent with a dedifferentiated chordoma. Diagn. Cytopathol. 1998;19:378–381. © 1998 Wiley-Liss, Inc.  相似文献   

6.
7.
Pulmonary mucinous adenocarcinoma (PMA) is the terminology recently proposed in the new International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society (IASLC/ATS/ERS) International Multidisciplinary Classification of Lung Adenocarcinoma Guidelines for most tumors previously classified as mucinous bronchioloalveolar carcinomas (mBACs). PMA is histologically characterized by lepidic growth and at least some degree of invasive growth of goblet or columnar neoplastic cells with abundant intracytoplasmic mucin. We report here the cytologic features of PMA in a bronchial brushing specimen. The patient is an 84‐year‐old woman with a persistent dense consolidation in the right middle lobe of the lung found on non‐contrast computed tomography (CT) scan. Bronchial brushing smears showed a monotonous population of columnar neoplastic cells forming “drunken honeycomb”‐like cell clusters. The neoplastic cells displayed inconspicuous cytologic atypia. The concurrent transbronchial tissue biopsy and the resection specimen confirmed the diagnosis of PMA. Due to the bland nuclear features, the neoplastic cells in the bronchial brushing specimen were interpreted as benign at the time of the initial diagnosis, demonstrating a diagnostic pitfall of bronchial brushing cytology. A high index of suspicion is recommended when a lung lesion with “drunken honeycomb”‐like cell clusters is encountered in bronchial brushing specimens. The review of the literature regarding the recently designated PMA is presented. Diagn. Cytopathol. 2013. © 2011 Wiley Periodicals, Inc.  相似文献   

8.
The successful postfunctionalization of multiarm star polystyrene (PS) with pentafluorophenyl and allyl moieties at the periphery is demonstrated employing modular thiol‐para‐fluoro and photoinduced radical thiol‐ene double “click” reactions, respectively. α‐Fluoro and α‐allyl functionalized PS (α‐fluoro‐PS and α‐allyl‐PS) are in situ prepared by atom transfer radical polymerization of styrene and their mixture is used as macroinitiator in a crosslinking reaction with divinyl benzene (DVB) yielding (fluoro‐PS)m–polyDVB–(allyl‐PS)m multiarm star polymer. It is found that the multiarm star polymer includes nearly identical number of arms possessing pentafluorophenyl and allyl moieties at the periphery. The obtained multiarm star polymer is then reacted with 1‐propanethiol through thiol‐para‐fluoro “click” reaction to give (propyl‐PS)m–polyDVB–(allyl‐PS)m multiarm star polymer, which is subsequently reacted with N‐acetyl‐l ‐cysteine methyl ester via radical thiol‐ene “click” reaction in order to give well‐defined heterofunctionalized (propyl‐PS)m–polyDVB–(cysteine‐PS)m multiarm star polymer, with higher molecular weight and narrow molecular weight distribution. Multiarm star polymers are characterized by using viscotek triple detection gel permeation chromatography, 1H, and 19F NMR.

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9.
10.
The nucleus "k", in the reticular core of the rabbit caudal pons, is divided into a large medial (composed of dorsal k1 and ventral k2) and a small lateral (k3) subdivision. In this study, the nucleus "k" subdivisions were examined in the rabbit with respect to projections to the cortex of rostral (rPML; face-forelimb region) and caudal (cPML; hindlimb region) paramedian lobule of the cerebellum. The retrograde fluorescent labeling method with Fast Blue (FB) and Diamidino Yellow (DY) was used. Numerous single FB or DY labeled neurons were found in defined regions of all nucleus "k" subdivisions bilaterally, with an ipsilateral preponderance. The distribution of these neurons indicated that afferents originating from different nucleus "k" subdivisions terminated in overlapping regions within the rPML and the cPML rather than in separate domains. Apart from this, double FB + DY labeled neurons (n = 104) were intermingled within a common region of single labeling, but exclusively on the ipsilateral side. Such neurons occupied predominantly the central and lateral regions of the caudal two thirds of the k1 subdivision, and were scattered in the caudal half of k2 as well as throughout the entire rostrocaudal extent of the k3 subdivision. The size of labeled perikarya varied from 20 to 40 microm in diameter. The number of neurons with branching axons was considerably lower than those with single projections to the rPML and the cPML. It amounted to about 3% in k1 and k3, and 2% in the k2 subdivision. However, this population may form an intralobular link between two somatotopically non-corresponding PML regions. The present study provides a morphological basis for further investigations for comparison with other species using both anatomical and electrophysiological methods, also with respect to other connections of the nucleus "k".  相似文献   

11.
12.
Intracellular recordings have been made from myotomal motoneurones during “fictive swimming” in the in vitro preparation of the lamprey spinal cord, while monitoring the efferent burst activity in the ventral roots. The pattern of rhythmic activity in the motoneurones is described, as well as how synaptic inputs from the premotoneuronal level exert their control of motoneurone activity. (1) All motoneurones investigated displayed rhythmic, symmetric oscillations of their membrane potential during “fictive swimming”. The period of depolarization occurred in phase with the burst discharge in the ventral root containing the motoneurone axon. (2) About one-third of the cells fired bursts of action potentials during the depolarized phase, while the remaining motoneurones exhibited subthreshold oscillations. (3) Intracellular injection of chloride ions reversed the sign of the hyperpolarized phase, demonstrating phasic active inhibition of the motoneurones during rhythmicity. (4) The depolarized phase was unaffected after chloride injection, showing that the motoneurones also received phasic active excitation. (5) “Pre-triggered” averaging of the motoneurone recording (using the ventral root spikes from other motoneurones for triggering), revealed that some degree of synchronous excitation of several motoneurones occurred, suggesting common excitation from the same premotor-interneurones. It is concluded that the rhythmic oscillations of membrane potential in lamprey myotomal motoneurones during “fictive locomotion” depend on phasic excitation alternating with phasic active inhibition. The premotoneuronal mechanism responsible for this control may consist of reciprocally organized groups of excitatory and inhibitory interneurones.  相似文献   

13.
A diffuse peritoneal mesothelioma is a rare tumor. Exfoliative cytology forms the first step in the diagnosis of mesothelioma, since most of these cases presented with effusion. Despite well established cytomorphological features, a challenge exists in differentiating mesothelial cells, including reactive and malignant types from carcinoma cells and macrophages. Presence of “signet‐ring” cells increases the diagnostic challenge as these can be forms of benign and malignant cells. Ancillary techniques like immunohistochemical (IHC) markers and ultrastructural analysis form useful adjunct in substantiating exact diagnosis. We report an unusual case study of a diffuse peritoneal mesothelioma in a 57‐years‐old lady, with no history of asbestos exposure, presenting with recurrent ascites, diagnosed on ascitic fluid cytology and on histology as an adenocarcinoma, based upon the presence of “signet‐ring” cells. On review, clinicopathological correlation with IHC was helpful in forming correct diagnosis. Diagn. Cytopathol. 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

14.
A series of well‐defined miktocycle number‐eight‐shaped copolymers composed of cyclic polystyrene (PS) and cyclic poly(ε‐caprolactone) (PCL) have been successfully synthesized by a combination of atom transfer radical polymerization (ATRP), ring‐opening polymerization (ROP), and “click” reaction. The synthesis involves three steps: 1) preparation of tetrafunctional initiator with two acetylene groups, one hydroxyl group and a bromo group; 2) preparation of two azide‐terminated block copolymers, N3‐PCL‐(CH?C)2‐PS‐N3, with two acetylene groups anchored at the junction; and 3) intramolecular cyclization of the block copolymer through “click” reaction under high dilution. The 1H NMR, FT‐IR, and gel permeation chromatography (GPC) techniques are applied to characterize the chemical structures of the resulting intermediates and the target polymers. Their thermal behavior is investigated by differential scanning calorimeter (DSC). The decrease in chain mobility of eight‐shaped copolymers restricts the crystallization of PCL.

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15.
We have analyzed chromosome breaks in 8 patients with Fanconi anemia (FA), 42 with “idiopathic” aplastic anema (AA), 15 first-degree relatives of FA patients, and 13 controls. Their lymphocytes were treated in culture with three concentrations of mitomycin-C (MMC). A 60-fold increase in breaks was observed in FA patients as compared to AA patients, regardless of severity of clinical signs. The MMC-stress test was standardized to clearly differentiate FA from other pancytopenias in doubtful cases. Also, the effect of storage of MMC in solution was investigated. The data on SCEs of 12 subjects tested, 10 mo apart, showed an inverse relationship between length of storage of MMC and chromosome damage. The 10-month-old solution induced only one half as many SCEs as it induced at 4 months. Further, the usefulness and power of diepoxybutane (DEB) in detection of FA heterozygotes was investigated in 12 first-degree relatives of patients with Fanconi anemia and 12 healthy controls. The mean number of chromosome breaks per mitosis by DEB stress in obligate heterozygotes was 0.08 in comparison to 0.06 in controls. Four of twelve control subjects showed proportions of breaks almost identical to or higher than those of FA heterozygotes, ie, 0.12, 0.10, 0.10, and 0.11 breaks per mitosis. The responses of healthy controls to DEB could be separated into two groups: one with mean chromosome breaks of 0.11 per mitosis, and a second with mean breaks of 0.04 per mitosis. Thus, it appears that heterozygote detection by DEB stress of cultured lymphocytes is not unequivocal.  相似文献   

16.
Dominant Optic Atrophy and Deafness (DOAD) may be associated with one or more of the following disorders such as myopathy, progressive external ophthalmoplegia, peripheral neuropathy, and cerebellar atrophy (“DOA‐plus”). Intra‐ and interfamilial variability of the “DOA‐plus” phenotype is frequently observed in the majority of the patients carrying the same mutation in the OPA1 gene. We are describing two familial cases of “DOA‐plus” carrying the same c.1334G>A (p.Arg445His) mutation in OPA1 and disclosing different clinical, pathological and biochemical features. The two patients showed different expression levels of the mitochondrial OMI/HTRA2 molecule, which acts as a mitochondrial stress sensor and has been described to interplay with OPA1 in in vitro studies. Our data offer the cue to inquire the role of OMI/HTRA2 as a modifier gene in determining the “DOAplus” phenotype variability.  相似文献   

17.
The polymerization of methyl acrylate and styrene in the presence of 1,1‐diphenylethylene (DPE) is investigated to monitor the impact of different monomers on the structure of DPE‐containing polymers. Poly(methyl acrylate) (PMA) and polystyrene (PSt) with low molecular weight are synthesized and characterized. According to the results of the 1H nuclear magnetic resonance (1H‐NMR) spectroscopy, DPE is incorporated into PMA and PSt polymer chains as diphenyl‐substituted structure. The resulting PMA polymers containing only one DPE unit show good agreement with the mass spectrometry results obtained by electrospray‐ionization quadrupolar time‐of‐flight mass spectrometry. The gel permeation chromatography results of PSt polymers are consistent with the molecular weight obtained by 1H‐NMR, indicating that each PSt polymer chain has only one DPE molecule.

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18.
The preparation and characterization of a series of poly(methyl methacrylate)‐block‐poly(butyl acrylate)‐block‐poly(methyl methacrylate) ABA triblock copolymers and their clay nanocomposites via in situ ATRP is reported. The molecular weights and the chemical structures of these nanocomposites are characterized by means of GPC, FTIR, and NMR analyses. DSC, AFM, and SAXS analyses prove a nanophase‐separated morphology in the block copolymer/clay nanocomposites. DMA analysis demonstrates an additional reinforcing effect of nanoclay in the block copolymer nanocomposites. AFM analysis indicates that the bulk polymer has a cylindrical morphology that is unaffected in the nanocomposite, as corroborated by SAXS analysis.  相似文献   

19.
20.
A series of donor‐acceptor (D‐A) π‐conjugated polymers, based on indacenodithienothiophene (IDTT) as an electron‐donating unit and quinoxaline as an electron‐deficient moiety, are synthesized via a Pd‐catalyzed Stille cross‐coupling polymerization. Molecular characteristics, photovoltaic parameters, and optoelectronic properties are examined through structural differences corresponding to thienyl versus phenyl side group substitutions on the IDTT and the non‐fluorinated versus the monofluoro quinoxaline derivatives. One of the most important outcome is that the power conversion efficiency (PCE) in the studied polymers is more device architecture dependent (conventional vs inverted) rather than chemical structure dependent. From single junction solar cells based on bulk heterojunction polymer:[6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM) systems as the active layer, a maximum PCE of 5.33% has been achieved from the polymer containing the thienyl substituent on the IDTT and one fluorine atom on the quinoxaline. This demonstrates that finding the optimum molecular weight of ThIDTT‐QF or introducing the monofluoro‐quinoxaline in a regioregular motif in the polymer backbone significantly higher PCE can be expected versus the fully optimized high performance PhIDTT‐Q conjugated polymer.  相似文献   

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