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41.
Journal of Digital Imaging - Measurement of angles on foot radiographs is an important step in the evaluation of malalignment. The objective is to develop a CNN model to measure angles on...  相似文献   
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Sneddon-Wilkinson disease (subcorneal pustular dermatosis) is an uncommon disorder. An unusual association with seronegative arthritis is reported with review of literature.  相似文献   
44.
The hypothesis that P-glycoprotein (P-gp) mediates the renal secretion of organic cations was tested by functional expression of mRNAs in theXenopus laevis oocyte system. Efflux of 2-deoxytubercidin (dTub), a substrate for the renal organic cation transporter (OCT) but not for P-gp, was enhanced by injection of renal mRNA but not by injection of mRNA from P-gp-overexpressing cells (MDCK cells transduced with the cDNA for humanMDR1). The functional capacity of the MDCK-MDR mRNA was established by its ability to reduce, the steady-state uptake of a classical P-gp substrate, vinblastine. Thus, these data indicate OCT and P-gp to be distinct entities. TheXenopus oocyte system provides a functional approach to further characterize the OCT.Work supported by NIH Grant RO1DK41606 from the Institute for Digestive Diseases and Kidney, and NIH Cancer Center Core Grant, CA 16672 from the National Cancer Institute  相似文献   
45.
The Wobbler mouse is a useful small animal model for the study of human motoneuron diseases. Besides showing the loss of motoneurons when the symptoms are expressed around the age of 3 weeks, we have also demonstrated the presumed ‘sprouting' of neuronal processes in the cervical spinal ventral horn which contain immunoreactive (IR) serotonin (5-HT), substance P (SP) and methionine and leucine enkephalins (ME, LE), as well as thyrotropin-releasing hormone (TRH). This occurs during the symptomatic period when IR-5-HT, ME and LE sprout at Stage 1, around the age of 3 weeks, whereas IR-SP sprouts only at a late stage (stage 4) of the disease (at age 3 months). The present investigation shows that the presumed sprouting occurs even before the appearance of symptoms and prior to significant motoneuron losses. IR-5-HT containing neuronal processes sprout by postnatal day 7, whereas IR-SP, -ME, -LE, and -TRH processes sprout by day 14. Hypothetically the early sprouts may contribute to the loss of motoneurons. They also respond to ciliary and brain derives neurotrophic factors cotreatment. IR-SP neuronal processes, although they sprout by day 14, show normal fiber density by the time symptoms appear (stage 1, age 21 days). However the SP sprouting is biphasic and a significant increase in number also occurs at an advanced stage of the disease (stage 4, age 3 months).  相似文献   
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Several A-ring-modified analogues of the DNA-binding antitumor agent DC-81 (5) have been synthesized in order to study structure-reactivity/cytotoxicity relationships. For two molecules (23 and 30) the modifications required the addition of a fourth ring to give the novel dioxolo[4,5-h]- and dioxano[5,6-h]pyrrolo[2,1-c][1, 4]benzodiazepin-11-one (PBD) ring systems, respectively. Another three analogues (34, 38, and 48) have the native benzenoid A-ring replaced with pyridine, diazine, or pyrimidine rings to give the novel pyrrolo[2,1-c][1,4]pyridodiazepine, pyrrolo[2,1-c][1, 4]diazinodiazepine, and pyrrolo[2,1-c][1,4]pyrimidinodiazepine systems, respectively. The other new analogues (16a,b) have extended chains at the C8-position of the DC-81 structure. During the synthesis of these compounds, a novel tin-mediated regiospecific cleavage reaction of the dioxole intermediate 18 was discovered, leading to the previously unknown iso-DC-81 (20). In addition, an unusual simultaneous nitration-oxidation reaction of 4-(3-hydroxypropoxy)-3-methoxybenzoic acid (8) was found to produce 3-(4-carboxy-2-methoxy-5-nitrophenoxy)propanoic acid (9), a key intermediate, in high yield. In general, the results of cytotoxicity and DNA-binding studies indicated that none of the changes made to the A-ring of the PBD system significantly improved either binding affinity or cytotoxicity in comparison to DC-81. This result suggests that the superior potency of natural products such as anthramycin (1), tomaymycin (2), and sibiromycin (3) is due entirely to differences in C-ring structure, and in particular exo or endo unsaturation at the C2-position and C2-substituents containing unsaturation. This study also provided information regarding the influence of A-ring substitution pattern on the relative stability of the interconvertible N10-C11 carbinolamine, carbinolamine methyl ether, and imine forms of PBDs.  相似文献   
47.
Having presented the provisional results of the 1991 Census of India in tabular form, the author discusses the policy implication of the data. During the 1981-91 decade, India witnesses a 160.99 net increase in population, which brought the country's total population to an estimated 844.32 million. The annual growth rated during the decade was 2.1%. The author explains that these alarming population figures reflect the failure of the government's population program. The author warns that unless the Planning Commission develops new strategies, the upcoming 5-year plans. The author explains that the failure of family planning is due primarily to the low literacy rate -- especially the female literacy rate is 29% (and 25% among rural women). The author also discusses the problems of urbanization and the work force. During the past decade, cities grew at a somewhat slower rate than in previous decades, meaning that the absorptive capacity of the cities has gone down. Nonetheless, the urban population grew by 58 million during 10-year period. The urban infrastructure is virtually collapsing, with 30-50% of the urban population living in slums. The data also reveals the structural stagnation of the economy. The agricultural sector, which accounts for about 2/3 of the work force, registered only slight decreases during the decade, signifying a marginal shift from agriculture to nonagricultural activity. Furthermore, population growth has aggravated the unemployment problem. Finally, the author addresses the issue of the sex ratio (females/1000 males), which declined from 934 in 1981 to 929 in 1991, which indicates a continued prejudice against women.  相似文献   
48.
Tephrosia purpurea (family: Fabaceae), which is used in traditional remedies for the treatment of febrile attacks, enlargement and obstruction of liver, spleen, and kidney, was found to have significant antileishmanial activity, and has been extensively fractionated to locate the abode of activity. A fraction (F062) obtained from N‐butanol extract of T. purpurea showed consistent antileishmanial activity at 50 mg/ kg × 5 days by oral route against Leishmania donovani infection in hamsters. Activity was further confirmed in a secondary model, i.e., Indian langur monkeys (Presbytis entellus). Thus, the fraction F062 from this plant possesses potential to produce significant antileishmanial activity by oral route without producing any toxic side effects. Drug. Dev. Res. 60:285–293, 2003. © 2003 Wiley‐Liss, Inc.  相似文献   
49.

The Garhwal Himalayas are a part of a unique ecosystem, with sharp agro-climatic variations within a very small geographical area (53,485 km2). The varied agro-climatic situations result in different cropping systems and socio-economic lifestyles that could likely affect the nutritional status of the people living in this region. This article will attempt to explore the impact of these variables (namely, age, family size, education, income, calorie and protein intake, land holding, number of animals, and wheat production) on the body mass index (BMI) of the population residing in the Garhwal Hills. A total of 1,030 subjects were studied from the three agro-climatic zones (406 from the high hills, 292 from the mid hills, and 332 from the low hills). It has been found that the people living in the high hills are the most undernourished, as the lowest percentage of people (52.6 per cent) with an acceptable BMI and the highest percentage of people in the severely malnourished category (11.1 per cent) are found here. People living in urban areas have a better nutritional status. Correlation studies show that the nutritional status of the population improves with age, literacy levels, and small family size. In some cases, calorie and protein intake have a positive impact on the health of the people, whereas size of land holding, number of animals, and income of the family do not have any significant influence on nutritional status.  相似文献   

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