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51.
The application (up to 5 kg ha-1) of monocrotophos or quinalphos to four types of agricultural soils significantly stimulated the mineralization of peptone-nitrogen and the oxidation of ammonium-nitrogen. In soils treated with 2.5 kg ha-1 of either insecticide, the rate of ammonification and nitrification was fairly rapid after 2 and 4 weeks of incubation. The enhancement of both transformations, mediated by microorganisms, was significantly more in the quinalphostreated soils. The results suggest that a balance between the effect of insecticides on insect pests and their impact on beneficial microbial activities in soil must be determined.  相似文献   
52.
BACKGROUND: To evaluate outcomes after minimally invasive or thoracolaparoscopic esophagectomy (TLE) with thoracoscopic mobilization of the esophagus and mediastinal esophagectomy in prone position. Esophagectomies are being performed increasingly by a minimally invasive route with decreased morbidity and shorter hospital stay compared with conventional esophagectomy. Most series report thoracoscopic mobilization of the esophagus and mediastinal lymphadenectomy in the left lateral position with respiratory complications up to 8% and prolonged operative time, probably because of inadequate stance of the surgeon during the thoracoscopic part. This study shows the potential of the thoracoscopic part of the procedure in prone position to ease these difficulties. STUDY DESIGN: From January 1997 through April 2005, TLE was performed in 130 patients. All patients had histologically proved squamous cell carcinoma of the middle third of the esophagus. Only one (0.77%) patient received neoadjuvant chemotherapy. The thoracoscopic part of the procedure was performed in prone position with excellent ergonomics, translating into less operative time and better respiratory results. We performed a minilaparotomy to retrieve the specimen owing to bulky tumors. Feeding jejunostomy and pyloromyotomy were performed in all patients. RESULTS: There were 102 men and 28 women. Median age was 67.5 years (range 38 to 78 years). There was no conversion to open method. Median ICU stay was 1 day (range 1 to 32 days) and median hospital stay was 8 days (range 4 to 68 days). Perioperative mortality was 1.54% (n = 2). Anastomotic leak rate was 2.31% (n = 3). There was no incidence of tracheal or lung injury and a very low incidence of postoperative pneumonia. At mean followup of 20 months (range 2 to 70 months), stage-specific survival was similar to open and other minimally invasive series. CONCLUSIONS: TLE with thoracoscopic part in prone position is technically feasible, with a low incidence of respiratory complications and less operative time required. It provides comparable outcomes with other techniques of minimally invasive esophagectomy and most open series. In our experience, we observed a low mortality rate (1.54%), hospital stay of 8 days, and low incidence of postoperative pneumonia. It has the potential to replace conventional and other techniques of minimally invasive esophagectomy.  相似文献   
53.
Extrapyramidal symptoms in unmedicated schizophrenia   总被引:1,自引:0,他引:1  
Studies of spontaneous extrapyramidal symptoms, dyskinesia and parkinsonism, in unmedicated schizophrenia are of importance in understanding their underlying pathology and relation to the psychosis. This is a study of extrapyramidal symptoms using Abnormal Involuntary Movements Scale for dyskinesia and Simpson-Angus Scale for parkinsonism in 143 schizophrenia patients who never received antipsychotic medication. Psychopathology was measured using the Positive and Negative Syndrome Scale. Dyskinesia was present in 35% of patients and parkinsonism in 15%. The two disorders coexisted in 11 subjects. Orofacial dyskinesia, rigidity and tremor were common symptoms noted. There was no significant change in the rates and total scores of dyskinesia and parkinsonism with gender, age, duration of illness or age at onset of psychosis. Dyskinesia was unrelated to psychopathology. Parkinsonism score correlated positively with the motor symptom cluster of psychopathology. Dyskinesia and parkinsonism scores correlated positively with each other and parkinsonism score discriminated presence of dyskinesia. The associations between the spontaneous abnormal movements and other aspects of schizophrenia differed from those described in treated patients. Dyskinesia and parkinsonism are an integral part of the schizophrenia disease process whose relationship with other factors could be influenced by antipsychotic drug treatment.  相似文献   
54.
The EEG bipolar power spectra provide more localization than spectral measures obtained from monopolar referencing strategies, and have been shown to be useful endophenotypes of psychiatric disorders such as alcoholism. We estimated the additive genetic heritability of resting bipolar EEG power spectra in a large sample of non-twin sibling pairs. The corresponding heritabilities ranged between 0.220 and 0.647 and were highly significant at all 38 electrode pairs for theta (3-7 Hz), low-alpha (7-9 Hz), high-alpha (9-12 Hz), low-beta (12-16 Hz), middle-beta (16-20 Hz) and high-beta (20-28 Hz) frequency bands. The heritabilities were the highest in the high-alpha and low-beta bands at most electrode pairs. The heritabilities were most variable across the head in the three beta bands. Other heritability patterns were also identified within each frequency band. Our results suggest that substantial proportions of the variability in the bipolar EEG measures are explained by genetic factors.  相似文献   
55.
BACKGROUND: Visual P300 is consistently lower in alcohol-dependent individuals, their offspring and subjects at risk. Delta and theta event-related oscillations (ERO) are the major contributors to the P300 signal. The total and evoked power in delta and theta bands in the 300 to 700 ms post-stimulus window (corresponding to the zone of P300 maxima) was compared between adolescent offspring of alcoholics (high-risk) and age-matched normal controls (low-risk), to assess the utility of the risk markers. METHODS: EEG was recorded during the performance of a visual oddball task. The S-transform algorithm decomposed the EEG signals into different frequency bands and the group differences in total and evoked power in the oscillatory responses during the P300 time window (300 to 700 ms) were analyzed using a multivariate design. Similar analysis was performed on P300 peak amplitude for the target. RESULTS: The high-risk group showed significantly lower parietal post-stimulus evoked and total power in the delta band for targets. A decrease in total power was seen centrally and parietally in the theta band. The P300 peak amplitude in the parietal electrodes was also significantly lower in the high-risk group. CONCLUSIONS: The decreased total theta power and total and evoked delta power for visual targets in high risk individuals may serve as an endophenotypic marker in the development of alcoholism and other disinhibitory disorders. The differences seen between the offspring of alcoholics and controls may have a cholinergic basis. The ERO measures appear to be more robust than the P300 amplitude in differentiating the groups.  相似文献   
56.
A simple and efficient protocol for the synthesis of novel 2,6-bis(4-methoxyphenyl)-1-methylpiperidin-4-one oxime esters 4(a–q) is described. Initially, p-anisaldehyde 1 was condensed (Mannich reaction) with acetone and ammonium acetate trihydrate afforded 2,6-bis(4-methoxyphenyl)piperidin-4-one 2. Then, methylation followed by oximation with hydroxylamine hydrochloride (NH2OH?HCl) furnished a key scaffold 4. Further, to explore the enhanced biological properties of the piperidin-4-one core i.e. the key scaffold 4 was conjugated with substituted benzoyl chlorides in the presence of anhydrous K2CO3 as base to obtain novel 2,6-bis(4-methoxyphenyl)-1-methylpiperidin-4-one oxime esters 4(a–q) in excellent yields. The newly synthesized compounds were characterized by elemental analysis, IR, 1H NMR, 13C NMR and mass spectroscopic techniques, and screened for their in vitro antioxidant and antimicrobial activities. Most of the compounds exerted positive efficacy towards the biological assays performed. Among the synthesized analogues, compounds 4l and 4m exhibited promising antioxidant activity and on the other hand compounds 4b and 4d manifested persuasive antibacterial activity, whereas compound 4b displayed stupendous antifungal activity against A. flavus strain.  相似文献   
57.
We report an analysis of more than 240,000 loci genotyped using the Affymetrix SNP microarray in 554 individuals from 27 worldwide populations in Africa, Asia, and Europe. To provide a more extensive and complete sampling of human genetic variation, we have included caste and tribal samples from two states in South India, Daghestanis from eastern Europe, and the Iban from Malaysia. Consistent with observations made by Charles Darwin, our results highlight shared variation among human populations and demonstrate that much genetic variation is geographically continuous. At the same time, principal components analyses reveal discernible genetic differentiation among almost all identified populations in our sample, and in most cases, individuals can be clearly assigned to defined populations on the basis of SNP genotypes. All individuals are accurately classified into continental groups using a model-based clustering algorithm, but between closely related populations, genetic and self-classifications conflict for some individuals. The 250K data permitted high-level resolution of genetic variation among Indian caste and tribal populations and between highland and lowland Daghestani populations. In particular, upper-caste individuals from Tamil Nadu and Andhra Pradesh form one defined group, lower-caste individuals from these two states form another, and the tribal Irula samples form a third. Our results emphasize the correlation of genetic and geographic distances and highlight other elements, including social factors that have contributed to population structure.Microarray technology has generated unprecedented quantities of data on human genetic variation. These data are useful for fine-scaled inferences of human evolutionary history (Jakobsson et al. 2008; Li et al. 2008; Novembre et al. 2008; Tian et al. 2008) and, under some circumstances, the estimation of individual ancestry (Seldin et al. 2006; Bauchet et al. 2007; Price et al. 2008; Tian et al. 2008). In this context, the new data have contributed to a better and more nuanced understanding of the relationship between genetics and “race” (Race, Ethnicity, and Genetics Working Group 2005; Witherspoon et al. 2007). In addition, a more thorough knowledge of between-population genetic variation also has been important in improving the design and interpretation of case-control studies of common diseases (Wellcome Trust Case Control Consortium 2007; Nelson et al. 2008; Price et al. 2008).For a variety of reasons, most studies have focused primarily on European populations (Seldin et al. 2006; Bauchet et al. 2007; Novembre et al. 2008; Price et al. 2008; Tian et al. 2008), and worldwide coverage of human populations remains incomplete. For example, the Human Genome Diversity Project (HGDP) database, one of the most widely used resources, lacks coverage in the Indian subcontinent. Other major regions, such as Eastern Europe and northern Africa, are also underrepresented in databases of human genetic variation.Among these underrepresented populations, those of the Indian subcontinent, which contains one-sixth of the world''s inhabitants, are of particular interest. The origins of and relationships among Indian populations are the subjects of continuing debate (Bamshad et al. 1998, 2001; Basu et al. 2003; Vishwanathan et al. 2004; Watkins et al. 2005; Rosenberg et al. 2006; Chaubey et al. 2007), but most previous genetic studies of these populations have been based on modest data sets. Indian populations are also used increasingly in linkage and case-control studies of genetic disease (Alcais et al. 2007; Chambers et al. 2008; Holliday et al. 2008). A better understanding of the genetic structure in India will facilitate these studies.Here, along with another 21 populations from around the world, we analyzed six Indian populations, including five caste populations and one tribal population, from two southern Indian states (Andhra Pradesh and Tamil Nadu). The inclusion of caste populations from different states and with different languages allowed us to assess the effects of social status, geography, and language on genetic structure in Indian populations. We have also included Daghestanis from the Caucasus region and Ibans from Sarawak, Malaysia to improve coverage in other underrepresented regions. Our analysis offers new insights on the genetic affinities and evolution of populations residing between commonly studied populations in sub-Saharan Africa, Europe, and East Asia.  相似文献   
58.
59.
The efficacy and safety of transvenous embosurgery for sigmoid sinus dural arteriovenous fistula (DAVF) using the internal jugular vein approach is well known. Embosurgery of cavernous sinus DAVF has also been described utilizing a superior ophthalmic vein approach. The first report of a sigmoid sinus DAVF endosurgical repair via a superior ophthalmic vein approach in a patient without internal jugular vein access is presented.  相似文献   
60.
Insight and psychopathology in never-treated schizophrenia   总被引:2,自引:1,他引:1  
Insight is a feature of schizophrenia related to psychopathology, which could be modified by treatment. The real relationship will be more evident in the never-treated state. This study compared insight and its relationship to psychopathology in 143 never-treated patients with chronic schizophrenia with 183 treated patients. The treated patients had not received any structured intervention for improvement of insight. The item on insight and judgment from the Positive and Negative Syndrome Scale for schizophrenia was used as a measure of insight. Never-treated patients were more ill and poorer in insight than the TT group. Sex, age, duration of illness, negative symptoms related to insight only in the TT group. Positive symptoms score correlated with insight in both the groups, but negative symptoms correlated with insight only among the treated patients. Delusions, uncooperativeness, and poor attention predicted 27% of variation in the level of insight in the never-treated, whereas age; duration of illness; and symptoms of emotional withdrawal, difficulty in abstract thinking, and uncooperativeness predicted 30.3% of variation in insight of the TT group. The observed differences between the never-treated and treated subjects were due to influence of treatment on the association between insight and psychopathology. A subgroup of patients with a treatment-resistant trait of negative symptoms associated with poor insight was hypothesized.  相似文献   
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