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991.
992.
Tons of peel and rag are generated each year by industries of citrus fruit juices. These by-products are used either for the elaboration of pectin or as substrate for enzyme production. Talaromyces flavus produces extracellular pectinesterase and polygalacturonase after 24 h in submerged culture supplemented with 0.5-0.8% citrus pectin preceded by preculture for 24 h in 2% (w/v) sucrose or in solid substrate culture on passion fruit peel, lemon or orange pulp pellets after 3-6 days of incubation. Chromatographic profiles in a CM-Sepharose column of liquid and solid cultures were very similar, consisting of one endopoligalacturonase (endo-PG I) and one pectinolytic complex constituted by an endopoligalacturonase (endo-PG II) and pectinesterase. Pectin and pectate lyases were undetectable in both media. In Talaromyces flavus the synthesis of pectinases was repressed by glucose and finally controlled by the concentration of products from pectic enzymes degradation.  相似文献   
993.

Gemcitabine and cisplatin combination (Gem–Cis) is a commonly used regimen in metastatic breast cancer (MBC), with proven activity in phase II trials. It is mostly used as a salvage regimen for progressive disease refractory to anthracyclines and taxanes, and when liver dysfunction secondary to liver metastasis precludes these drugs. Retrospective review of medical charts was conducted for patients treated with Gem–Cis for MBC in a single institution in Brazil between January 2004 and July 2007. The purpose of this study was to evaluate the outcomes and toxicity of Gem–Cis in a broad indication, including patients with deteriorated performance status (PS) and liver dysfunction, which were excluded from clinical trials. Fifty-six patients were included. Median age was 52 years, 46.4% were hormone–receptor negative, 57.2% received 3 or more prior chemotherapy lines, and 34 had liver metastasis. The median overall survival (OS) was 7.6 months, the median progression-free survival was 3.3 months, and the response rate was 21.2%. In variable analysis, PS was significantly associated with OS, even after adjusting to other factors. Toxicities included grades 3 or 4 anemia in 19.3%, neutropenia in 21.1%, and thrombocytopenia in 12.3%. Gem–Cis was a relatively active combination in this population that typically carries a poor prognosis. The subgroup of patients with favorable PS experienced longer survival, even when liver metastasis and hepatic dysfunction were a concern. Toxicity was manageable and it was not correlated with PS or liver dysfunction.

  相似文献   
994.
R Andrade 《Brain research》1991,548(1-2):81-93
The cerebral cortex receives a prominent cholinergic innervation which is thought to play an important role in regulating its normal function. Electrophysiological studies have shown that activation of cholinergic receptors results in a marked enhancement of excitatory stimuli onto cortical neurons and it has been suggested that this effect is secondary to the blockade of several voltage- and calcium-dependent potassium conductances in these cells. It is reported here that, in addition to these effects, activation of muscarinic receptors in the prefrontal cortex elicits the appearance of a slow calcium-dependent inward current in response to the generation of action potentials. This inward aftercurrent produces a slowly decaying depolarizing afterpotential which, when activated by stimulation of the cell, can summate with the carbachol-induced depolarization greatly increasing its magnitude. As a result the ability of muscarinic receptor to elicit a depolarization and excite cells in this region can be dramatically potentiated by evoked cell activation. This effect expands the range of mechanisms by which muscarinic receptors can facilitate excitatory inputs and provides a mechanism by which the association of brief excitatory stimuli to cholinergic stimulation can selectively enhance muscarinic responses among discrete cell populations in the cerebral cortex.  相似文献   
995.
Application of a solution of 1-glutamine, 75 mM, to the pia-arachnoid surface of the dorsolateral neocortex of rabbits under dial-urethane anaesthesia was found to reversibly render the tissue insusceptible to spreading depression. It is suggested that this amide may play a part in the opposition normally offered by the tissue to undergo spreading depression. Some evidence is adduced which seems to support this suggestion.  相似文献   
996.
997.
OBJECTIVE: To study the efficacy of cognitive rehabilitation combined with acetylcholinesterase inhibitor (AChE-I) treatment in patients with mild Alzheimer's disease and their relatives. METHOD: Thirteen patients with mild Alzheimer's disease treated with rivastigmine 6-12 mg/day for more than two months started cognitive rehabilitation training. Before and after the cognitive rehabilitation training patients were assessed through cognitive tests, activities of daily living scale, neuropsychological battery and scales to evaluate caregivers' depressive and anxiety symptoms. Six patients were randomized to a combined treatment group (AChE-I plus cognitive rehabilitation and caregiver support) and seven patients to a control group (AChE-I only) and followed up for five months. RESULTS: Mini-Mental State Examination (MMSE) scores (p = 0.047) and backward digit span scores (p = 0.018) were significantly different between the groups on follow-up. The combined treatment group showed a better positive treatment effect on cognitive and neuropsychological tests applied to patients and reduction of psychiatric symptoms was observed in their caregivers (nonsignificant). CONCLUSION: Cognitive rehabilitation associated with AChE-I treatment can potentially be useful to stabilize or improve cognitive and functional performance of patients with mild Alzheimer's disease and can reduce caregivers' psychiatric symptoms.  相似文献   
998.

Aims

To assess the effects of a Pilates exercise program compared to conventional pelvic floor muscle training (PFMT) protocol on pelvic floor muscle strength (PFMS) in patients with post‐prostatectomy urinary incontinence.

Methods

Patients were randomized into three treatment groups (G1: Pilates, G2: electrical stimulation combined with PFMT, and G3: control group). Duration of therapy was 10 weeks. Baseline assessment included the 24 h pad‐test and the ICI‐Q questionnaire. PFMS was measured using a manometric perineometry device at baseline and 4 months after radical prostatectomy (RP). The level of significance was P < 0.05.

Results

One hundred twenty three patients were randomized and 104 patients completed the study protocol (G1: n = 34; G2: n = 35; G3: n = 35). Post‐treatment assessment showed statistically significant improvements in maximum strength in G2, increased endurance in G1 and G2, and increment of muscle power in all three groups (P < 0.05). However, there were no significant differences in the mean changes of maximum strength, endurance, and muscle power between groups after treatment (P > 0.05). G1 and G2 achieved a higher number of fully continent patients than G3 (P < 0.05). At the end of treatment, 59% of patients in G1, 54% in G2, and 26% in G3 were continent (no pads/day).

Conclusions

Improvements in PFMS parameters were distinct among active treatment groups versus controls, but did not predict recovery of urinary continence at final assessment. The Pilates method promoted similar outcomes in the proportion of fully continent patients when compared to conventional PFMT 4 months after RP.  相似文献   
999.
We screened 615 gram-positive isolates from 150 healthy children for the presence of the erm(A), erm(B), erm(C), erm(F), and mef(A) genes. The mef(A) genes were found in 20 (9%) of the macrolide-resistant isolates, including Enterococcus spp., Staphylococcus spp., and Streptococcus spp. Sixteen of the 19 gram-positive isolates tested carried the other seven open reading frames (ORFs) described in Tn1207.1, a genetic element carrying mef(A) recently described in Streptococcus pneumoniae. The three Staphylococcus spp. did not carry orf1 to orf3. A gram-negative Acinetobacter junii isolate also carried the other seven ORFs described in Tn1207.1. A Staphylococcus aureus isolate, a Streptococcus intermedius isolate, a Streptococcus sp. isolate, and an Enterococcus sp. isolate had their mef(A) genes completely sequenced and showed 100% identity at the DNA and amino acid levels with the mef(A) gene from S. pneumoniae.  相似文献   
1000.
The notarium is a rigid bony structure, which resulted from the fusion of thoracic vertebrae of some pterosaurs and birds. It is high variable, ranging from two to six fused thoracic vertebrae. In this study, we reviewed and analyzed approximately 270 specimens of neornithine birds (representing 80% of the living orders) and some fossils in order to identify the number of fused vertebrae, degree and sites of vertebral fusion, occurrence of sutures, and other structures of potential phylogenetic and functional significance. These data were analyzed using a recent time-calibrated molecular phylogenetic tree and principal component analyses analysis evaluating the relationship with long bones in order to reconstruct macroevolutionary trends related to the evolution of the notarium. The occurrence of this structure shows a mosaic distribution over neornithine phylogeny, originating several times independently, especially during the Paleogene, in predominantly ground-dwelling forms. The notarium of these groups is characterized by: neural spines fused into single structure, intervertebral openings small to absent, large ventral keels forming ventral plates, and fused transverse processes. Derived neornithines, such as aquatic forms and long-legged birds, have a tendency to display a decreased degree of fusion between the vertebrae, which may indicate a reduction or disappearance of the notarium.  相似文献   
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