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1.
IntroductionMauritius, a small state, is among the few African countries where cancer registration is population based and nationwide. We reported trends in cancer incidence for twenty five years as well as the mortality to incidence ratio (MIR) as main quality indicator of the Mauritius National Cancer Registry (MNCR).Materials and methodsWe calculated age standardised incidence rates (ASRs) of cancers by sex and by 5 year age group for five successive year periods from 1991 to 2015. The average annual percentage change (AAPC) were determined by sex and cancer sites. MIRs were compared for the period 2001–2004 and 2012–2015.ResultsIn males, the most common cancer sites (in terms of ASRs per 100,000) were those of the colon-rectum (17.0), prostate (16.5), trachea-bronchus-lung (13.0), stomach (8.4) and lip-oral cavity-pharynx (7.7). The AAPC were +3.9%, +4.2%, +0.5%, -0.1% and -1.3% respectively. In females, the most frequent sites were breast (53.7), colon-rectum (13.2), cervix uteri (11.2), corpus uteri (7.7) and ovary (5.7). The AAPC were +3.4%, +4.4%, -2%, +5.2% and -0.1% respectively. The most significant decrease in MIRs among males were liver (1.9 to 1.0), stomach (1.3 to 0.8) and lung (1.7 to 1.2) cancers while among females, they were pancreas (3.4 to 1.3), liver (1.8 to 1.2) and stomach (1.5 to 0.8) cancers.ConclusionThe most common cancers were those associated with 'westernisation' of lifestyle. Our figures contrast with other Sub-Saharan Africa countries where infection related cancers are most predominant. The MNCR has also improved its data quality over time.  相似文献   

2.
α-Glucosidase activity was detected at the tip of the labellar contact chemosensory hair of the blowfly, Phormia regina. The enzyme split about 1 pmole of sucrose per hr per hair on average and the Michaelis constant for sucrose was about 50 mM. The activity of the enzyme was not solubilized into the incubation solution, but stuck stably to the tip of the sensory hair. From the cut end of the sensory hair a high activity of α-glucosidase eluted out. But its Michaelis constant was smaller by far than the one at the tip, suggesting that different types of α-glucosidase isozymes exist in the hair. The possibility that the enzyme at the tip of the sensory hair could be the sugar receptor is discussed.  相似文献   

3.
The rôle of the midgut, crop, and maxillae in the production and utilization of the cocoon-digesting enzyme was investigated in the silkworm, Bombyx mori.About a sixtyfold purified preparation of midgut protease was obtained by ammonium sulphate precipitation and column chromatography.Immunological studies by the agar diffusion method of Ouchterlony revealed that the crop and midgut proteases of the pharate adult are antigenically identical whereas that of the maxillary protease is different.From the results of extirpation experiments and previous studies it was shown that the midgut, crop, and maxillae play important rôles in the escape of moths from their cocoons.  相似文献   

4.
The zooplankton composition is studied in the thermokarst, glacial and meteorite lakes, channels, former riverbeds, and hollows in the basin of Anadyr’. We found 174 taxa: 78, Rotatoria, 55, Cladocera, and 41, Copepoda. The most diverse is the lake fauna: 51 taxa of Rotatoria, 48, Cladocera, and 37, Copepoda. The thermokarst Lake Maiorskoe hosts 68 taxa: 31, Rotatoria, 14, Cladocera, and 23, Copepoda, wheras the cold ultraoligotrophic Lake El’gygytgyn features only one species of Cyclop of the group scutifer Cyclops neymanae Strel., and Rotatoria and Cladocera are present as allochtonous forms. The Copepoda illustrate the relations of the Anadyr’ fauna with those of Europe, North America, and Japan.  相似文献   

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6.
In recent years, rapid diagnostic tests (RDTs) have been widely used for malaria detection, primarily because of their simple operation, fast results, and straightforward interpretation. The Asan EasyTest™ Malaria Pf/Pan Ag is one of the most commonly used malaria RDTs in several countries, including Korea and India. In this study, we tested the diagnostic performance of this RDT in Uganda to evaluate its usefulness for field diagnosis of malaria in this country. Microscopic and PCR analyses, and the Asan EasyTest™ Malaria Pf/Pan Ag rapid diagnostic test, were performed on blood samples from 185 individuals with suspected malaria in several villages in Uganda. Compared to the microscopic analysis, the sensitivity of the RDT to detect malaria infection was 95.8% and 83.3% for Plasmodium falciparum and non-P. falciparum, respectively. Although the diagnostic sensitivity of the RDT decreased when parasitemia was ≤500 parasites/µl, it showed 96.8% sensitivity (98.4% for P. falciparum and 93.8% for non-P. falciparum) in blood samples with parasitemia ≥100 parasites/µl. The specificity of the RDT was 97.3% for P. falciparum and 97.3% for non-P. falciparum. These results collectively suggest that the accuracy of the Asan EasyTest™ Malaria Pf/Pan Ag makes it an effective point-of-care diagnostic tool for malaria in Uganda.  相似文献   

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8.
The accumulation of detectable amounts of newly synthesized ribosomes has been shown to be prevented by ligaturing the nutritive cords between the oöcytes and the trophic syncytium of the Oncopeltus ovary. Unligatured control oöcytes on the opposite side of the same bug accumulated normal quantities of newly synthesized ribosomes under the same conditions. It is concluded that the oöcytes are inactive in the synthesis of ribosomes, this function being entirely the province of the trophic syncytium. Evidence is presented which supports the contention that the oöcytes are synthesizing transfer RNA as well as a high molecular weight, polydisperse, fraction which may be the maternal messenger RNA of the egg.  相似文献   

9.
Phosphatidylinositol 4-kinase IIIα (PI4KIIIα) is the lipid kinase primarily responsible for generating the lipid phosphatidylinositol 4-phosphate (PI4P) at the plasma membrane, which acts as the substrate for generation of the signaling lipids PIP2 and PIP3. PI4KIIIα forms a large heterotrimeric complex with two regulatory partners, TTC7 and FAM126. We describe using an integrated electron microscopy and hydrogen–deuterium exchange mass spectrometry (HDX-MS) approach to probe the architecture and dynamics of the complex of PI4KIIIα/TTC7/FAM126. HDX-MS reveals that the majority of the PI4KIIIα sequence was protected from exchange in short deuterium pulse experiments, suggesting presence of secondary structure, even in putative unstructured regions. Negative stain electron microscopy reveals the shape and architecture of the full-length complex, revealing an overall dimer of PI4KIIIα/TTC7/FAM126 trimers. HDX-MS reveals conformational changes in the TTC7/FAM126 complex upon binding PI4KIIIα, including both at the direct TTC7-PI4KIIIα interface and at the putative membrane binding surface. Finally, HDX-MS experiments of PI4KIIIα bound to the highly potent and selective inhibitor GSK-A1 compared to that bound to the non-specific inhibitor PIK93 revealed substantial conformational changes throughout an extended region of the kinase domain. Many of these changes were distant from the putative inhibitor binding site, showing a large degree of allosteric conformational changes that occur upon inhibitor binding. Overall, our results reveal novel insight into the regulation of PI4KIIIα by its regulatory proteins TTC7/FAM126, as well as additional dynamic information on how selective inhibition of PI4KIIIα is achieved.  相似文献   

10.
The Na,K-ATPase is a major ion transport protein found in higher eukaryotic cells. The enzyme is composed of two subunits, α and β, and tissue-specific isoforms exist for each of these, α1, α2 and α3 and β1, β2 and β3. We have proposed that an additional α isoform, α4, exists based on genomic and cDNA cloning. The mRNA for this gene is expressed in rats and humans, exclusively in the testis, however the expression of a corresponding protein has not been demonstrated. In the current study, the putative α4 isoform has been functionally characterized as a novel isoform of the Na,K-ATPase in both rat testis and in α4 isoform cDNA transfected 3T3 cells. Using an α4 isoform-specific polyclonal antibody, the protein for this novel isoform is detected for the first time in both rat testis and in transfected cell lines. Ouabain binding competition assays reveal the presence of high affinity ouabain receptors in both rat testis and in transfected cell lines that have identical K D values. Further studies of this high affinity ouabain receptor show that it also has high affinities for both Na+ and K+. The results from these experiments definitively demonstrate the presence of a novel isoform of the Na,K-ATPase in testis. Received: 4 December 1998/Revised: 1 February 1999  相似文献   

11.
The three species of flying fishes—Indo-Pacific Cypselurus poecilopterus, Central Pacific C. simus, and Eastern Pacific C. callopterus form a particular species group within the subgenus Poecilocypselurus. These species rather weakly differ in the body height, number of predorsal scales and number of gill rakers. The sculls of these three species are very much alike; there are just very small differences in the proportions of some bones and the number of skull lateral line canals and pores. It could be imagined that C. poecilopterus has appeared in the Indo-Malayan Archipelago area and thence extended in all directions (up to the coasts of the Eastern Africa, Northern and Eastern Australia, New Guinea and adjacent islands, the western islands of Polynesia and the waters of Japan). C. callopterus inhabiting warm waters of the Eastern Pacific and C. simus whose area is situated in the central part of the Pacific Ocean are seemingly derived from this species.  相似文献   

12.
Faecal material and cyclopoid copepods were collected during the expedition ANT IX/3, in the Halley Bay area (Weddell Sea, Antarctica), between January and February 1991. Faecal material comprised pellets produced by krill, copepods, ostracods and appendicularians. Cyclopoid copepods were represented by two genera, Oithona and Oncaea. In the Halley Bay area, higher concentrations of krill faecal material (420.9 mm3 m–2) and chl.-a (39.3 mg m–2) were found within the upper 200 m of the water column of the polynya than in ice-covered open-ocean areas (58.2 mm3m–2 and 25.5 mg m–2, respectively). At an ice-drift station, high concentrations of krill faecal strings under fest-ice were found. In addition, similarities between diatom assemblages in the pack-ice algae and krill faecal strings contents suggest an active utilization of ice-algae by krill populations. Sedimented material collected at 50 m depth by a sediment trap was dominated by krill faecal strings. Contents of small oval pellets (of probable cyclopoid copepod origin) resemble those of krill faecal pellets suggesting that coprophagy was involved. This suggestion is supported by: (1) The small quantity of food particles (other than krill faecal matter) available in the water column (< 0.3 g chl.-al–1). (2) The negative in situ correlation between krill faecal strings and cyclopoid copepods. (3) The structure of cyclopoid copepod buccal appendages, which are more adapted for raptorial feeding.  相似文献   

13.
Robert M. Dores 《Peptides》1982,3(6):913-924
Immunohistochemical studies on the pituitary of Anolis carolinensis detected ACTH-like, β-endorphin-like, and 16K fragment-like immunoreactivity in distinct clusters of cells in the anterior lobe; ACTH-like, αMSH-like, β-endorphin-like, and 16K fragment-like immunoreactivity was detected in all the cells of the intermediate lobe. Crude acid extracts of both lobes, when alayzed by radioimmunoassay, gave displacement curves in ACTH and β-endorphin assays which were parallel to the appropriate synthetic standard. Only extracts of the intermediate lobe gave parallel displacement curves in an αMSH radioimmunoassay. Extracts of both lobes crossreacted with antiserum to 16K fragment, but the displacement curves were not parallel to that of mouse 16K fragment standard. The levels of immunoreactive ACTH and β-endorphin in the intermediate lobe were approximately 8-fold higher than in the anterior lobe. Fractionation of anterior lobe and intermediate lobe extracts by either gel filtration on Sephadex G-75 in 10% formic acid or sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed multiple forms of ACTH-related and β-endorphin-related substances in both lobes. In the anterior lobe the major forms of immunoreactivity were, respectively, ACTH-sized and β-endorphin-sized. In the intermediate lobe the major forms of immunoreactivity were αMSH-sized, CLIP-sized, and β-endorphin-sized. In both lobes, antisera directed against ACTH and β-endorphin detected high molecular weight material with an apparent molecular weight slightly less than that of mouse pro-ACTH/endorphin; this material probably represents the putative common precursor for ACTH and β-endorphin in this species.  相似文献   

14.
α-Parinaric acid has been used to determine the degree of ordering of the hydrocarbon region of purified intracytoplasmic membranes of Rhodopseudomonas sphaeroides. The usefulness of α-parinaric acid as a probe of membrane fluidity was established by comparison of its fluorescent properties in phosphatidylcholine vesicles with those of the more commonly used fluorescent probe, 1,6-diphenyl-1,3,5-hexatriene. Both fluorescent probes were shown to monitor similar environments in the phosphatidylcholine vesicles when the phospholipids were maintained at temperatures above their phase transition temperature.The rotational mobility of α-parinaric acid in the intracytoplasmic membranes was determined from 0 to 50°C, a region where no phase transitions were detectable. The rotational mobility of α-parinaric acid dissolved in vesicles formed from total extracted intracytoplasmic membrane phospholipids, was 2–3-fold greater than that measured in the intact intracytoplasmic membranes; demonstrating that the presence of protein greatly reduces the mobility of the phospholipid acyl chains of the intracytoplasmic membranes. Due to the high protein content of these membranes, the perturbing effect of protein on acyl chain mobility may extend to virtually all the intracytoplasmic membrane phospholipid.  相似文献   

15.
The fungiid Heliofungia actiniformis is one of the most popular coral species in the Indonesian aquarium trade, yet information on the biology of this species is limited. H. actiniformis growth rates, population size–frequency distributions and the seasonality of recruitment rates were measured at three replicate sites in the Spermonde Archipelago, South Sulawesi. Growth and population models were applied to estimate coral ages, mortality rates and the size of maximum yield. Growth decreased linearly with polyp size. High numbers of attached polyps budded from clusters of stalks attached to the reef, with each cluster originating from the settlement of a sexually produced larva. Neither the settlement of sexual recruits, nor their asexual budding, showed seasonality. The overall population structure reflected the high mortality rates of young, attached polyps (Z = 0.5–0.6 yr−1), and the much lower mortalities of free-living individuals (Z = 0.05–0.08 yr−1). There were no statistically significant differences in overall mortality rates and the age–frequency distributions of polyps aged 0–15 years between the sites. Differences in the abundance of large H. actiniformis polyps at the three replicate sites were correlated with percent cover of coral rubble. The application of the Beverton and Holt model revealed the highest biomass per H. actiniformis recruit was 12 cm, corresponding to a polyp age of 20 years.  相似文献   

16.
Using the plasmid pNF1337 as template, a mRNA preparation has been obtained that directs the in, vitro synthesis of fMet-Val, the N-terminal dipeptide of the β subunit of RNA polymerase. RNA polymerase holoenzyme specifically inhibits the mRNA-directed synthesis of fMet-Val showing that the autoregulation by RNA polymerase of β,β′ synthesis is at the level of translation. L factor (nusA gene product) stimulates the synthesis of fMet-Val from a DNA template but not from mRNA. Rifampicin has no effect on the mRNA-directed synthesis of fMet-Val or the ability of RNA polymerase to inhibit fMet-Val synthesis.  相似文献   

17.
18.
The neurosecretory system of Labedura riparia has been described from sections and whole mounts using a variety of techniques. The pars intercerebralis contains two clusters of medial neurosecretory cells (MNC), each cluster consisting of 8 to 10 A-cells and occasional B-cells. The lateral sides of the brain have a few B-cells. The axons of the median neurosecretory cells terminate in the cephalic aorta (AO), whereas the axons of the lateral neurosecretory cells (LNC) terminate in the corpora cardiaca (CC). It appears that the neurosecretory material (NSM) elaborated in the MNC is stored in the cephalic aorta and that elaborated in the LNC is stored in the corpora cardiaca, which are two oval or elongate bodies composed of large chromophobe and small chromophil cells. Posteriorly there is the oval or elongate corpus allatum (CA) attached to the CC by thick nerves. The CA consists of one cell type only. Both CC and CA contain no A-cell neurosecretory material. It has been suggested that the neurosecretory system of L. riparia is composed of two complexes. One is formed by the medial neurosecretory cells for which the aorta functions as a neurohaemal organ, and the other is formed by lateral neurosecretory cells-lateral neurosecretory pathways-nervi corporis cardiaci-II in which the corpora cardiaca function as a neurohaemal organ.  相似文献   

19.
A reappraisal of chitinozoan distribution across the Ordovician-Silurian boundary on the Island of Anticosti has led to the recognition of a new zone, the Ancyrochitina ellisbayensis biozone, in the uppermost part of the Ellis Bay Formation. This biozone lies between the well defined Upper Ordovician Spinachitina taugourdeaui biozone and the lowest Silurian (Rhuddanian) Plectochitina nodifera biozone of the Becscie Formation. The occurrence of such diagnostic species as P. nodifera, Belonechitina postrobusta, Conochitina electa and Ancyrochitina ramosaspina in the Lower Silurian of Anticosti points to a close similarity to faunas in Estonia and north Latvia and indicates an age ranging from the Parakidograptus acuminatus to the Coronograptus cyphus in terms of graptolite zones. The chitinozoan biozonation harmonizes with that based on conodonts and, to a lesser extent, with the known graptolite faunal succession. Five new species: Ancyrochitina ellisbayensis sp. nov., Clathrochitina postconcinna sp. nov., Conochitina gunriveris sp. nov., Clathrochitina perexilis sp. nov., Bursachitina basiconcava sp. nov. and three species in open nomenclature are described.  相似文献   

20.
Summary Previous electrophysiological studies have shown that the olfactory organ (antennule) of the spiny lobster, Panulirus argus, has external chemoreceptors, which are selectively stimulated by adenosine 5-monophosphate (AMP) when present in seawater. Subsequent biochemical investigations revealed that AMP can be rapidly dephosphorylated by 5-ectonucleotidase/phosphatase activity associated with the olfactory sensilla (aesthetascs). In this study the deposition of cerium phosphate was used to examine the ultrastructural distribution of 5-ectonucleotidase/phosphatase activity in aesthetascs. Utilizing AMP as substrate, we found dephosphorylating activity to be associated with the outer membranes of both dendrites and auxiliary cells. Moreover, this activity was specifically localized to a narrow band that approximately corresponds to the transitional zone where dendrites develop cilia and branch extensively to form the outer dendritic segments. A similar distribution of the cerium phosphate reaction product was found when -glycerol phosphate was substituted for AMP. The alkaline-phosphatase inhibitor, levamisole, had no apparent effect on the deposition of reaction product when either AMP or -glycerol phosphate was used as substrate. The ectoenzymatic activity in the transitional zone may be of importance in clearing exogenous chemoexcitatory nucleotides from this region.Abbreviations ADP adenosine 5-diphosphate - AMP adenosine 5-monophosphate - ATP adenosine 5-triphosphate - EM electron microscopy  相似文献   

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