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1.
A Malla  R M Norman  E Helmes 《CMAJ》1987,136(11):1166-1171
To assess what factors determine the involuntary status of psychiatric patients, we reviewed the case records of 5729 patients consecutively admitted to one of four inpatient psychiatric facilities, including a mental hospital, in St. John''s between October 1975 and October 1978. Of the 5729 patients 5005 (87.4%) were voluntary and 724 (12.6%) involuntary. Involuntary patients were more likely than voluntary patients to be male, single and unemployed and to have been referred by police or transferred from another facility to the mental hospital, where most of the involuntary admissions occurred. They had higher rates of previous admissions to a psychiatric facility and of suicidal and violent behaviour, were more likely to have a diagnosis of schizophrenia or mania and were less likely to be suffering from depression or a neurotic disorder. In correspondence with differences in diagnosis, involuntary patients stayed in hospital more than twice as long as voluntary patients, were less likely to receive electroconvulsive therapy, minor tranquillizers and antidepressants, and were more likely to receive neuroleptics and lithium carbonate. Stepwise logistic regression analysis revealed that only the source of referral and a diagnosis of neurotic disorder had an independent effect on admission status. The findings are discussed in the context of the controversy over the parens patriae approach v. the legal approach to involuntary admission of psychiatric patients.  相似文献   
2.
The respiratory uptake or photosynthetic evolution of oxygen by mesophyll protoplasts of pea ( Pisum sativum L. cv. Arkel) were monitored during successive short. (3–5 min) cycles of darkness and illumination. The rate of respiration was nearly doubled after 3–4 short periods of illumination while there was a 15–20% enhancement in photosynthesis with cycles of illumination and darkness preceding illumination. Such interaction between photosynthesis and respiration was statistically significant when bicarbonate was present in the reaction medium. The inhibitors of photosynthesis [3(3,4–dichlorophenyl)-l,l-dimethylurea (DCMU), glyceraldehyde] decreased respiration after periods of illumination, whereas inhibitors of respiratory electron transport (Rotenone, antimycin A, NaN3) suppressed photosynthesis, as well. We suggest that a rapid beneficial interaction exists between photosynthesis and respiration in protoplasts, even during short cycles of light and darkness.  相似文献   
3.
Changes in foliage density distribution with altitude and its effect on shoot growth and flowering were studied in forest section planes (profiles) of subalpine forests and scrubs (Krummholz) in Nepal and Japan.Patterns of foliage in forest canopy were evaluated by an analysis of variance. Foliage densities were very high at high altitude canopies, but the change in spatial patterns along altitude differs in both areas.The spatial pattern of new shoot production was similar to that of current foliage density and was affected by the amount of foliage above the sample probably through light condition. Flowering of tall trees occurred in the surface of the upper canopy, but a shrub species flowered even under tree canopies.  相似文献   
4.
Cysticercosis, a disease of economic and public health importance, is caused by Cysticercus cellulosae, the metacestode stage of Taenia solium. Experimental induction of cysticercosis was achieved in young pigs by feeding an optimum dose of 20,000 T. solium (Indian strain) eggs after immunosuppression, to assess the effect of albendazole and development of the immune response to cysticercus antigens before and after treatment.

Histopathological studies revealed the presence of cysticerci in liver, lungs and muscles. Treatment with albendazole at 15 mg kg−1 body weight daily for 30 days starting from day 0 or 15 days post-infection resulted in 100% cure rates. Increases in antibody titre to crude soluble extract and a Sephadex G-200 purified antigenic fraction of Cysticercus cellulosae were found on days 25, 40 and 55 post-infection in untreated pigs and those in which treatment started on day 15 post-infection, whereas no increase in antibody response was observed in pigs in which treatment started on day 0.  相似文献   

5.
The pathology and physiology of breast cancer(BC),including metastasis,and drug resistance,is driven by multiple signaling pathways in the tumor microenvironment(TME),which hamper antitumor immunity.Recently,long non-coding RNAs have been reported to mediate pathophysiological developments such as metastasis as well as immune suppression within the TME.Given the complex biology of BC,novel personalized therapeutic strategies that address its diverse pathophysiologies are needed to improve clinical outcomes.In this review,we describe the advances in the biology of breast neoplasia,including cellular and molecular biology,heterogeneity,and TME.We review the role of novel molecules such as long non-coding RNAs in the pathophysiology of BC.Finally,we provide an up-to-date overview of anticancer compounds extracted from marine microorganisms,crustaceans,and fishes and their synergistic effects in combination with other anticancer drugs.Marine compounds are a new discipline of research in BC and offer a wide range of anti-cancer effects that could be harnessed to target the various pathways involved in BC development,thus assisting current therapeutic regimens.  相似文献   
6.
7.
Quercetin, a flavonol aglycone, is one of the most abundant flavonoids with high medicinal value. The bioavailability and pharmacokinetic properties of quercetin are influenced by the type of sugars attached to the molecule. To efficiently diversify the therapeutic uses of quercetin, Escherichia coli was harnessed as a production factory by the installation of various plant and bacterial UDP-xylose sugar biosynthetic genes. The genes encoding for the UDP-xylose pathway enzymes phosphoglucomutase (nfa44530), glucose-1-phosphate uridylyltransferase (galU), UDP-glucose dehydrogenase (calS8), and UDP-glucuronic acid decarboxylase (calS9) were overexpressed in E. coli BL21 (DE3) along with a glycosyltransferase (arGt-3) from Arabidopsis thaliana. Furthermore, E. coli BL21(DE3)/?pgi, E. coli BL21(DE3)/?zwf, E. coli BL21(DE3)/?pgi?zwf, and E. coli BL21(DE3)/?pgi?zwf?ushA mutants carrying the aforementioned UDP-xylose sugar biosynthetic genes and glycosyltransferase and the galU-integrated E. coli BL21(DE3)/?pgi host harboring only calS8, calS9, and arGt-3 were constructed to enhance whole-cell bioconversion of exogeneously supplied quercetin into 3-O-xylosyl quercetin. Here, we report the highest production of 3-O-xylosyl quercetin with E. coli BL21 (DE3)/?pgi?zwf?ushA carrying UDP-xylose sugar biosynthetic genes and glycosyltransferase. The maximum concentration of 3-O-xylosyl quercetin achieved was 23.78 mg/L (54.75 μM), representing 54.75 % bioconversion, which was an ~4.8-fold higher bioconversion than that shown by E. coli BL21 (DE3) with the same set of genes when the reaction was carried out in 5-mL culture tubes with 100 μM quercetin under optimized conditions. Bioconversion was further improved by 98 % when the reaction was scaled up in a 3-L fermentor at 36 h.  相似文献   
8.
Epoxyeicosatrienoic acids (EETs) are endothelium-derived eicosanoids that activate potassium channels, hyperpolarize the membrane, and cause relaxation. We tested 19 analogs of 14,15-EET on vascular tone to determine the structural features required for activity. 14,15-EET relaxed bovine coronary arterial rings in a concentration-related manner (ED(50) = 10(-6) M). Changing the carboxyl to an alcohol eliminated dilator activity, whereas 14,15-EET-methyl ester and 14,15-EET-methylsulfonimide retained full activity. Shortening the distance between the carboxyl and epoxy groups reduced the agonist potency and activity. Removal of all three double bonds decreased potency. An analog with a Delta8 double bond had full activity and potency. However, the analogs with only a Delta5 or Delta11 double bond had reduced potency. Conversion of the epoxy oxygen to a sulfur or nitrogen resulted in loss of activity. 14(S),15(R)-EET was more potent than 14(R),15(S)-EET, and 14,15-(cis)-EET was more potent than 14,15-(trans)-EET. These studies indicate that the structural features of 14,15-EET required for relaxation of the bovine coronary artery include a carbon-1 acidic group, a Delta8 double bond, and a 14(S),15(R)-(cis)-epoxy group.  相似文献   
9.
Chronic renal failure can be the cause of various disturbances in hormonal and electrolyte metabolism, including calcium and phosphate metabolism. The aim of this study was the evaluation of pyloric endocrine cells in Wistar rats with experimental uremia. Fragments of gastric pylorus were collected 30 days after nephrectomy. Paraffin embedded sections were stained with H+E and by silver impregnation. We also performed immunohistochemical reactions with the use of specific antibodies against calcitonin gene-related peptide (CGRP), synaptophysin (SY), somatostatin (ST), and neuronal specific enolase (NSE). The rats with experimental uremia showed an increase in the number of endocrine cells and in intensity of all the examined reactions.  相似文献   
10.
The complete thyroid and parathyroid gland removal leads to the abrupt reduction of calcitonin, which can be a factor stimulating growth and intensified activity of APUD system cells in the respiratory tract. Thus, neuroendocrine cells in the lungs and trachea in rats after thyroid and parathyroid removal were evaluated. Paraffin specimens of the examined organs were stained with H+E and impregnated with silver. Calcitonin, synaptophysin, somatostatin, and neuronal-specific enolase were detected immunohistochemically by the use of rabbit specific antibodies. Antibodies used in the study immunostained neuroendocrine cells of the examined organs. Rats with removed thyroid and parathyroid glands presented weakened reaction compared to the control group.  相似文献   
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