石片研究

石片是石制品的重要组成部分, 其分类须遵循逻辑划分, 研究应规范化、系统化和简单化。按照台面和背面特征划分石片类型越来越趋向共识。石片台面由其背面缘和破裂面缘构成,是由直线、折线和弧线相互组成的几何图形, 它的形状反映剥片思维的逻辑构想。依据单疤、双疤、多疤组合和单向、双向、多向组合观察石片背面有助于剥片流程的分析。从背面观测石片的长度和划分左右较为合理, 参照人的手掌和手指判定石片大小和依据黄金分割律确认石片的形态应该是较有理的选择。石片除了制作食物外, 更多功效的猜想也值得考虑, 如敬奉首领、示爱异性、切割头发胡须、挠痒痒和清理排泄物等。     

Experimental study of seita-fitting

The purpose of this study was to verify the difference between carrying a load on the sacrum (LOS) and on the lumbar vertebrae (LOL) in oxygen uptake, muscle activities, heart rate, cadence, and subjective response. Nine males (26.7 +/- 3.1 years old), each carrying a 7.5 kg carrier frame and a 40 kg load, walked on a treadmill at a speed of 50 m/min. EMGs were recorded from the trapezius, rectus abdominis, erector spinae, vastus lateralis, rectus femoris, vastus medialis, biceps femoris long head, tibial anterior, soleus, medial head of gastrocnemius, and the lateral head of gastrocnemius. For each subject the integrated EMG (IEMG) was normalized by dividing the IEMG in the LOL and LOS by the IEMG in a no-load condition (NL) for each investigated muscle. The following was significantly higher in LOL than in LOS: oxygen uptake; IEMG of the tibial anterior, soleus, and medial head of gastrocnemius; cadence; and rated perceived exertion. However, IEMG of the erector spinae was significantly lower in LOL than in LOS. These results suggest that seita-fitting in LOS causes a decrease of leg muscle activities, which causes oxygen uptake to decrease beyond the increase of the erector spinae activity.     

Pharmaco-toxicological study of diterpenoids

Azorella compacta, Azorella yareta and Laretia acaulis (Apiaceae) are native species from the high Andes Mountains, northeastern Chile, and they have being traditionally used to treat asthma, colds and bronchitis, illnesses with inflammation and pain as the main symptoms. Interestingly, there are no scientific reports available on their benefits or toxicity. This study was carried out with the purpose of validating the medicinal use of these species and to discover anti-inflammatory and analgesic new molecules. As a working hypothesis, we have proposed that these medicinal species contain bioactive compounds with anti-inflammatory and analgesic effects. In this context, azorellanol, 13-hydroxy-7-oxoazorellane and 7-deacetylazorellanol, three diterpenoids previously isolated only from these plants, were subjected to farmaco-toxicological evaluation. Their topical anti-inflammatory and analgesic activities along with acute toxicities or innocuosness were also investigated. Our results indicate the absence of toxic and side effects in mice. All compounds presented dose-related inhibition of pain. 13-hydroxy-7-oxoazorellane was the most potent analgesic but it was less effective than sodium naproxen, the reference drug. Azorellanol exhibited the highest topical anti-inflammatory potency on AA (arachidonic acid) and TPA (12-deoxyphorbol 13-tetradecanoate) induced oedema, and it effect was similar to the reference drugs (nimesulide and indomethacin). Probably, its mechanism of action could be explained through the inhibition to cyclo-oxygenase activity. Our results corroborate the anti-inflammatory and analgesic effects of these species, and it justifies their use in folk medicine.     

NMR study of paper

High quality antique sheets of paper have been characterized by ¹H NMR relaxations and ¹³C CP MAS spectra. Paper can be regarded as a bicomponent material made of cellulose and water plus a small amount of organic and inorganic impurities. Semicrystalline fibrous cellulose, rich in water, is present in the I and I_β forms. The amorphous cellulose, with a low water content, contains a higher amount of paramagnetic impurities and it is characterized by quite short ¹H spin-lattice relaxations and by ¹¹³C resonances with noticeable chemical shifts. Ad hoc tailored pulse sequences are able to produce ¹³C CP MAS spectra in which only the amorphous content of paper is clearly observed. It is shown that water is fully bound to the cellulose lattice. It also seems reasonable to formulate the hypothesis that a larger concentration of paramagnetic ions is located in the amorphous fraction of highly degraded paper compared with paper in good condition.     

Kinetic study of seita-fitting

We have already presented two studies of the traditional carrier frame, the seita. In our first study, we reported on seita users supporting loads not on the lumbar vertebrae but on the sacrum. In the second study, we showed that carrying a load on the sacrum was efficient in terms of metabolic rate, muscle activity, cadence and subjective responses. The purpose of this study was to verify the effect of carrying a load on the sacrum in terms of gait pattern. We compared the kinetic parameters produced while carrying a load on the sacrum (LOS) with those produced while carrying a load on the lumbar vertebrae (LOLV). Maximum propulsive force and medial impulse were significantly larger in LOS than in LOLV. These results suggested that a normal gait pattern was maintained more in LOS conditions than in LOLV conditions. This indicated that seita-fitting was efficient for carrying and transporting loads.     

Morphogenetic study of brachiopods

In this work we discuss the results of ontogenetic and morphobiological approaches to phylogenetic reconstructions of articulate brachiopods on the basis of morphogenetic data. These data provide the basis for generalizations concerning phylogeny and system of orders. The ontogenetic approach was the subject of criticism mainly because of arbitrary establishment of the homology of brachiopods. The constraints of the morphobiological approach are associated with the phenomena of morphological evolution without adaptive explanation so far. As an example of these phenomena, homeomorphism of brachiopods can be considered. Prospects for morphogenetic studies of brachiopods can be connected with the study of characteristic elements of their shell structure, such as porosity and mantle channels.     

A study of oxidative stress in cervical cancer- an institutional study

Cervical cancer is the second most common cause of cancer-related death among women worldwide, especially in developing countries. Oxidative stress has been associated with cervical cancer. Many studies demonstrated that the low level of antioxidants induces the production of free radicals that cause lipid peroxidation, DNA, and protein damage leading to mutations that favors malignant transformation. This is a case-control institutional study conducted to evaluate the level of oxidative stress in cervical cancer patients and the age-matched healthy controls. We measured level of TBARS expressed as MDA, activity of SOD and GSH level by the spectrophotometric method, and level of 8-OHdG was estimated using a competitive sandwich ELISA assay. Our results showed a significant increase in the level of lipid peroxidation in group IV when compared to the control, group II and group III (p < 0.001). The activity of SOD was also significantly higher in group IV when compared to the control group (p < 0.001), group II (p < 0.001), and group III (p < 0.001). The level of GSH was also significantly lower in group IV when compared to the control group (p < 0.01), group II (p < 0.01), and group III (p < 0.01). The level of 8-OHdG was significantly higher in group IV than in the other groups (p < 0.01). The results suggest that oxidative stress is involved in the pathogenesis of cervical cancer, which is demonstrated by an increased level of lipid peroxidation and higher levels of 8-OHdG and an altered antioxidant defense system.     

Genome-wide population-based association study of extremely overweight young adults--the GOYA study

Background

Thirty-two common variants associated with body mass index (BMI) have been identified in genome-wide association studies, explaining ∼1.45% of BMI variation in general population cohorts. We performed a genome-wide association study in a sample of young adults enriched for extremely overweight individuals. We aimed to identify new loci associated with BMI and to ascertain whether using an extreme sampling design would identify the variants known to be associated with BMI in general populations.

Methodology/Principal Findings

From two large Danish cohorts we selected all extremely overweight young men and women (n = 2,633), and equal numbers of population-based controls (n = 2,740, drawn randomly from the same populations as the extremes, representing ∼212,000 individuals). We followed up novel (at the time of the study) association signals (p<0.001) from the discovery cohort in a genome-wide study of 5,846 Europeans, before attempting to replicate the most strongly associated 28 SNPs in an independent sample of Danish individuals (n = 20,917) and a population-based cohort of 15-year-old British adolescents (n = 2,418). Our discovery analysis identified SNPs at three loci known to be associated with BMI with genome-wide confidence (P<5×10⁻⁸; FTO, MC4R and FAIM2). We also found strong evidence of association at the known TMEM18, GNPDA2, SEC16B, TFAP2B, SH2B1 and KCTD15 loci (p<0.001), and nominal association (p<0.05) at a further 8 loci known to be associated with BMI. However, meta-analyses of our discovery and replication cohorts identified no novel associations.

Significance

Our results indicate that the detectable genetic variation associated with extreme overweight is very similar to that previously found for general BMI. This suggests that population-based study designs with enriched sampling of individuals with the extreme phenotype may be an efficient method for identifying common variants that influence quantitative traits and a valid alternative to genotyping all individuals in large population-based studies, which may require tens of thousands of subjects to achieve similar power.     

Pharmacokinetic study of stobadine

The aim of this paper is to provide a brief overview of most important results of stobadine kinetic studies in rats, dogs, and human volunteers. In these studies, stobadine dihydrochloride and stobadine dipalmitate was used for intravenous and oral administration, respectively. To evaluate kinetic properties of stobadine and its metabolites, TLC, HPLC, GLC, GC-MS, radiometric, and fluorometric methods were developed and used.     

Etiological study of omphalocele

Summary The epidemiological, teratological and genetic data on 134 index patients with omphalocele (79 isolated and 55 multiple ones) and on 134 matched controls born in Hungary 1970–1976 were studied from medical records and by retrospective interview. The stillbirth rate and infant mortality are significantly higher, and there is intrauterine weight retardation and more frequent preterm delivery. The distribution of maternal age-groups shows a U-shaped trend in isolated omphalocele. Spontaneous abortions were significantly higher, particularly in previous pregnancies of mothers of index patients. A strikingly higher incidence of early and late toxaemia was found in the pregnancies of mothers of the isolated omphalocele group. Sib occurrence was not found in 161 brothers and sisters. Thus amniotic fluid AFP examination is not recommended in subsequent pregnancies. The occurrence of other congenital abnormalities corresponds to random risk.     

Electrochemical study of mononucleosome

The electrochemical behavior of mononucleosome has been studied in parallel with circular dichroism and trypsin degradation. In mononucleosome, DNA is never adsorbed at the electrode surface. A model of flat adsorption of the mononucleosome via histones is proposed.     

The "study" role of past National Institutes of Health study sections

The original National Institutes of Health (NIH) study sections had two missions. The review of grant applications was the enduring one that we all recognize. The second original function, less remembered today, was to stand ready to advise the NIH, and in fact the entire community in a given biomedical field, on the current state of that discipline, as well as to opine on what new vistas were arising and to suggest (or occasionally even launch) appropriate courses of action. The present contribution is intended to remind us of this lesser-known original function of NIH study sections. We might ponder whether today's study sections, although more overworked than Sisyphus, should again take up this second function.     

Crystallographic study of plastocyanins

Crystals of plastocyanins from pea and corn leaves have been obtained. Both are suitable for X-ray structure analysis with a resolution up to 1.8 Å. The crystal form of plastocyanin from pea leaves belongs to the space group P2₁2₁2₁ with unit cell dimensions: $\text{a = 49.0}\text{A}\text{?}\text{, b = 53.3}\text{A}\text{?}\text{, c = 82.6}\text{A}\text{?}$. The assumed number of protein molecules per asymmetric unit of the unit cell is two. Crystals of the oxidized (Cu²⁺) and reduced (Cu⁺) forms are isomorphic. No essential differences in spot intensities for the main zone with a resolution of 3 Å were revealed. The crystal form of plastocyanin from corn leaves belongs to the space group P1 with unit cell parameters: $\text{a = 24.8}\text{A}\text{?}\text{, b = 30.0}\text{A}\text{?}\text{, c = 58.5}\text{A}\text{?}$ and α = 96° 10′, β = 87°08′, γ = 78°40′. The assumed number of protein molecules per asymmetric unit is two.     

Design of a binary biomarker study from the results of a pilot study

Biomarkers are increasingly used in clinical and epidemiologic studies. Prior to these studies, small pilot studies are often conducted to assess the reproducibility of the biomarker. This article discusses how the results of a pilot study can be used to design subsequent studies when the biomarker is a binary assessment. We consider situations in which the pilot study has two factors (e.g., laboratory and individual) that are either crossed or nested. We discuss how binary random-effects models can be used for estimating the sources of variation and how parameter estimates from these models can be used to appropriately design future studies. We also show that fitting a linear variance components model that ignores the binary nature of the data is a simple alternative method that results in nearly unbiased and moderately efficient estimators of important design parameters. We illustrate the methodology with data from a study assessing the reproducibility of p53 immunohistochemistry in bladder tumors.     

固氮酶的研究进展

固氮酶将N2还原为NH3的过程是自然界实现氮循环的重要环节。固氮酶是由γ2型二聚体组成的Fe蛋白和α2β2异四聚体组成的MoFe蛋白组成。固氮酶催化的机制包括铁蛋白的氧还循环和钼铁蛋白的氧还循环两部分。Klebsiella pneumoniae的nif基因簇由20个基因组成,构成了8个转录单位,总长度24206bp,其操控机制是多水平、多层次的调控过程。同时综述了固氮酶的多样性,目前已经发现的有钼铁固氮酶、钒铁固氮酶、铁铁固氮酶以及在Strpomyces thermoauophicus内存在的与已知的三种固氮酶体系明显不同的固氮体系。     

Immunogenetic study of porcine IgG

Three allotypes of IgG were identified in pig. Based on data obtained on electrophoretic mobility as well as on results of the International Comparative Test ISABR for pig blood group, polymorphic proteins and enzymes (1987-1988), the allotypes are specified as markers of two different IgG subclasses and are referred to as IgG1a, IgG2b and IgG2c. The former of these is established as corresponding to the already known IGH3 C1, and the other two had not been earlier described. In herds of pigs being bred in the Georgian SSR, the IgG1a allotype frequencies in Kakhetinskaya, Large White, Landrase and Lithuanian white were 0.84, 0.93, 0.91 and 0.94, respectively, whereas for the IgG2b allotype it ran 0.89, 0.73, 0.79, and 0.69 in the order mentioned. The IgG2c allotype was not registered in samples under examination.     

Photoacoustic study of iron-deficiency anaemia

A photoacoustic spectrum of a smear of whole blood clearly shows all of the details of the haem absorption in an optical spectrum and good optical absorption data without a data extraction procedure. There are three peaks; γ (420 nm), β (550 nm), and α (585 nm) in the band 350–700 nm. For iron-deficiency anaemia the peak/peak ratios, ratios of the value of peak γ to that of the peak β and peak α, and the integral/integral ratios, ratios of the value of the integral under the peak γ to that under the peak β, peak α, peak β and peak α are closely related to the variation of haemoglobin concentration. Linear relationships among the ratios and the Hb concentration are found. These ratios could be a good index of haem synthesis disturbance.     

Ethological study of early language

Sign language studies of cross-fostered chimpanzees measure the effect of special rearing conditions on the development of very young chimpanzees. Cross-fostered chimpanzees, like human children, develop gradually in a process that takes many years. Here we discuss details of the procedure, the overlap between human and chimpanzee infants in the contents of the first 50-item vocabularies, and the ways in which the signs of the chimpanzees exhibit the fuzziness of natural language categories. We also compare the cross-fostering approach with more traditional modular approaches to the study of language-like behavior in nonhuman animals. Project Washoe was originally supported by grants MH-12154 from the National Institute of Mental Health and GB-7432 from the National Science Foundation. We gratefully acknowledge this support and the support that later sign language studies of chimpanzees have received since then from NIH, NSF, the National Geographic Society, the Grant Foundation, the Spencer Foundation, the University of Nevada, and the UNR Foundation.     

Roentgencephalometric study of cranial interrelations

Lateral X-ray films of the skull obtained in 50 normal adult males were used for studies of correlations between 26 characteristics of the size, shape, and position of the face and nine characteristics of the neurocranium in all mutual combinations. The results disclosed that the relations between individual cranial components were regulated by certain principles. The correlations between size dimensions were mostly slight; a closer relationship showed some characteristics of the shape and position. The most important variable exerting an effect on the configuration of the skull as a whole represented the angle of the cranial base which produced the rotation of the neurocranium and the face and thus acted on a series of other correlations. Of some importance as well was the length of the mandibular ramus acting on the shape and position of the lower jaw and on the vertical maxillomandibular relations. The close relationship between the anteroposterior position of both jaws was due to compensation mechanisms rather than to the identical size of both jaws. On normalization of the disturbed saggital jaw relations, the dentoalveolar components of both jaws as well as the subalveolar component of the mandible participated equally. In vertical direction the lower face showed a certain developmental independence. The discussed interrelations formed the basis for studies of the mechanisms regulating the intracranial development and the changes occurring in various anomalies, as well as for understanding the compensation and adaptation abilities of individual cranial components.