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We have constructed a 2.4-cM resolution genetic linkage map for chromosome 7q that is bounded by centromere and telomere polymorphisms and contains 66 loci (88 polymorphic systems), 38 of which are uniquely placed with odds for order of at least 1000:1. Ten genes are included in the map and 11 markers have heterozygosities of at least 70%. This map is the first to incorporate several highly informative markers derived from a telomere YAC clone HTY146 (locus D7S427), including HTY146c3 (HET 92%). The telomere locus markers span at least 200 kb of the 7q terminus and no crossovers within the physical confines of the locus were observed in approximately 240 jointly informative meioses. The sex-equal map length is 158 cM and the largest genetic interval between uniquely localized markers in this map is 11 cM. The female and male map lengths are 181 and 133 cM, respectively. The map is based on the CEPH reference pedigrees and includes over 4000 new genotypes, our previously reported data plus 29 allele systems from the published CEPH version 5 database, and was constructed using the program package CRI-MAP. This genetic linkage map can be considered a baseline map for 7q, and will be useful for defining the extent of chromosome deletions previously reported for breast and prostate cancers, for developing additional genetic maps such as index marker and 1-cM maps, and ultimately for developing a fully integrated genetic and physical map for this chromosome.  相似文献   
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The use of liquid nitrogen for the removal of warts has advantages over electrocautery in certain circumstances. Although the incidence of recurrences after liquid nitrogen is higher than after cautery, it causes considerably less scarring. It is most useful in dealing with peri-ungual and multiple warts. The technique is simple and a supply of liquid nitrogen can be kept on hand in the office at relatively low cost.  相似文献   
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In an attempt to establish the exact location of calcium within the preacetabular glands of cercariae of Schistosoma mansoni, these larvae were exposed to reagents (potassium oxalate, potassium pyroantimonate, chloranilic acid, and silver nitrate) useful in the detection of calcium, and were subsequently observed with the aid of light and electron microscopes. Cercariae incubated in potassium oxalate and viewed in polarized light showed birefringence only in the preacetabular gland funduses. At the ultrastructural level, the preacetabular glands of potassium oxalate-treated cercariae had no electron-dense precipitate, but instead had translucent, irregularly shaped inclusions, similar to spaces left by volatilized calcium oxalate as described by others. Pyroantimonate treatment, on the other hand, localized the reaction in the electron-lucent areas of the light-spotted granules. The von Kossa silver nitrate procedure destroyed the secretory granules; therefore, an electron-dense precipitate was distributed throughout the gland. However, pretreatment with chloranilic acid before fixation preserved the granules, and subsequent exposure to the von Kossa silver nitrate gave a reaction identical to that obtained with the pyroantimonate alone. When viewed in polarized light, chloranilic acid-incubated cercariae showed birefringence in the fundus and duct areas.  相似文献   
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The heated biuret-Folin method for determining protein consistently measures 90% of the total nitrogen of filtered algae samples as protein-N without the need of mechanical disruption as long as the heating period in biuret is 100 min at 100 C. Data indicate this protein assay measures total protein on all species tried and for naturally occurring mixtures of species plus detritus. Dilute algal suspensions with as little as 0.05 μg-atom particulate protein N.liter -1 can he concentrated by fltration on glass fiber filters to 1.0 μg-atom particulate protein-N per filter, the optimal amount of sample for a 5 ml volume of biuret. The filtered algae samples can be stored for several weeks frozen before assaying, if necessary.  相似文献   
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Paleolimnology of Qilu Hu,Yunnan Province,China   总被引:4,自引:0,他引:4  
Qilu Hu is a large (A = 36.9 km2), shallow (zmax = 6.8 m) lake that lies at an elevation of 1797 m above msl on the Yunnan Plateau, southern China. Lake waters are hard (Mg = 3.2m eq L–1, Ca = 1.3 meq L–1 ), fresh (conductivity = 380 S cm –1), and productive (Secchi < 40 cm). An 11-m sediment core has a basal 14C age of 30960 ± 860 B.P. Sediments between 11 m and 6 m are high in % dry weight, rich in clay components Al2O3, Fe2O3, K2O, MgO, and low in organic C (6.1%), carbonate-C (<1.0%), total N (<3.2 mg g–1), and total S (<-1.7 mg g–1). Diatoms and pollen indicate open-water conditions between 9.0 m and 6.0 m (1342011790 B.P.). Above 6.0 m, CaCO3 and organic matter concentrations increase relative to clastics. The transition marks a change to shallow-water conditions as inferred from diatoms and pollen, and probably reflects a shift to drier climate. Uppermost (80-0 cm) red clays were deposited rapidly, probably as a consequence of recent (decades to centuries) riparian disturbances (e.g. agriculture, lake-bottom reclamation, urban development). Dates assigned to events in the Qilu Hu profile are tentative because of potential hard-water-lake error.  相似文献   
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Against the background of cercarial fine structure, ultrastructural changes were compared in schistosomules of Schistosoma mansoni 30 min and 1 hr after their production in vivo by skin penetration and in vitro by shear pressure. The same developmental pattern was observed in schistosomules of both derivations. In vitro schistosomules, however, developed more slowly, resembled cercariae more closely, and varied less among organisms than did in vivo schistosomules. The greatest morphological changes were observed in the 1-hr in vivo schistosomules. These were as follows: (1) in tegument, formation of transient microvilli, a hepatalaminate outer membrane and accented surface invaginations, loss of glycocalyx, movement outward of cyton vesicles via bridges, accumulation of multilaminate bodies around bridge openings; (2) in the anterior organ (oral sucker), movement of head gland vesicles via the ducts into tegument followed by collapse of the gland fundus, disappearance of the circumfundal cells and two large support cells, and the appearance in these areas of membranes and parenchymal cells; (3) secretion of the acetabular gland contents, collapse of the glands and replacement by membranes and parenchymal cells; (4) peristaltic activity of the digestive tract as shown by alternate areas of lumen constriction and dilation; (5) loss of bladder and contraction of the small aboral collecting tubules; and (6) conversion of heterochromatic parenchymal cell nuclei to euchromatic. In contrast, the 1-hr in vitro shear schistosomules resembled 30-min in vivo schistosomules, retaining many cercarial features.  相似文献   
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BackgroundA better understanding of case management practices is required to improve inpatient pediatric care in resource-limited settings. Here we utilize data from a unique health facility-based surveillance system at six Ugandan hospitals to evaluate the quality of pediatric case management and the factors associated with appropriate care.MethodsAll children up to the age of 14 years admitted to six district or regional hospitals over 15 months were included in the study. Four case management categories were defined for analysis: suspected malaria, selected illnesses requiring antibiotics, suspected anemia, and diarrhea. The quality of case management for each category was determined by comparing recorded treatments with evidence-based best practices as defined in national guidelines. Associations between variables of interest and the receipt of appropriate case management were estimated using multivariable logistic regression.ResultsA total of 30,351 admissions were screened for inclusion in the analysis. Ninety-two percent of children met criteria for suspected malaria and 81% received appropriate case management. Thirty-two percent of children had selected illnesses requiring antibiotics and 89% received appropriate antibiotics. Thirty percent of children met criteria for suspected anemia and 38% received appropriate case management. Twelve percent of children had diarrhea and 18% received appropriate case management. Multivariable logistic regression revealed large differences in the quality of care between health facilities. There was also a strong association between a positive malaria diagnostic test result and the odds of receiving appropriate case management for comorbid non-malarial illnesses - children with a positive malaria test were more likely to receive appropriate care for anemia and less likely for illnesses requiring antibiotics and diarrhea.ConclusionsAppropriate management of suspected anemia and diarrhea occurred infrequently. Pediatric quality improvement initiatives should target deficiencies in care unique to each health facility, and interventions should focus on the simultaneous management of multiple diagnoses.  相似文献   
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