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991.
Three patients (2 female, 1 male) with recurrent infection, granulocytosis, impaired pus formation, and/or delayed umbilical cord separation were identified. Assessments of polymorphonuclear leukocytes (PMN)/monocyte function in each patient revealed profound abnormalities of adherence and adherence-dependent functions. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of their PMN lysates demonstrated a deficient or absent protein(s) of 138 kilodaltons (gp 138). Na3HB4 labeling demonstrated the absence of a major cell surface glycoprotein complex in each patient. Among parental and sibling PMN suspensions, functional assessments revealed no consistent abnormalities, although variably diminished gp138 was identified by SDS-PAGE and Na3HB4 labeling. Analysis by fluorescence-activated cell sorting and monoclonal antibodies (MAb) to LFA-1 alpha, OKM1 alpha, and their common beta subunit demonstrated a severe or total deficiency of PMN/monocyte surface expression of each protein among all patients; intermediate values were observed for parental and affected sibling suspensions, findings consistent with an autosomal recessive mode of inheritance for this disorder. Cell surface labeling (125I) and immunoprecipitation with the same MAb demonstrated the absence of these glycoproteins in addition to a 150-kilodalton protein (p150,95). Identical abnormalities of surface expression of patient lymphocytes blast-transformed with phytohemagglutinin (PHA) or Epstein-Barr virus were demonstrated. Further, significantly diminished natural killer cell cytotoxicity was observed for each patient tested. PHA blast-transformed patient lymphocytes labeled with [35S]methionine demonstrated a total absence of the beta molecule but indicated the presence of an LFA-1 alpha precursor. These findings indicate that LFA-1 alpha synthesis and surface expression require beta association. It is concluded that impaired inflammatory function in this disorder is casually related to a heritable deficiency of critical "adhesive" leukocyte glycoproteins.  相似文献   
992.
The alcohol dehydrogenase from horse liver is able to catalyze the oxidation of a number of 1,2-diols and α-aminoalcohols enantioselectively to l-α-hydroxyaldehydes and l-α-amino aldehydes. A decrease of enantioselectivity was found in reactions with 1,3-diols and substrates with hydrophobic substituent at position 3. α-Aminoalcohols are not substrates for yeast alcohol dehydrogenase, but the enzyme can catalyze the oxidation of most of the diols to l-hydroxyaldehydes. New methods for determination of the optical purity of α-hydroxy-and α-aminoaldehydes via converting them in situ to the corresponding acids, catalyzed by the aldehyde dehydrogenase from yeast, have been developed. The coupled alcohol dehydrogenase/aldehyde dehydrogenase has been extended to preparatory scale synthesis of optically pure l-α-hydroxyacids in the presence of a cofactor regeneration system. The active-site cubic-space section model has been shown not to be applicable to all substrates.  相似文献   
993.
994.
Genetic diversity among isolates of the bacterial plant pathogen Burkholderia solanacearum (synonym Pseudomonas solanacearum) race 3 biovar II of Kenya was determined by PCR with repetitive sequences (ERIC and BOX repetitive primer sets) and pulsed-field gel electrophoresis of genomic DNA digested by rare-cutting restriction endonucleases (RC-PFGE). The study comprised 46 isolates collected during 1992 from the major potato-growing regions of Kenya (45 were identified as race 3 biovar II, and 1 belonged to race 3 biovar N2) and 39 reference isolates from 19 other countries. RC-PFGE identified 10 distinct profile types among the Kenyan race 3 biovar II isolates (29 of the isolates exhibited identical profiles) and a further 27 distinct profile types among the reference isolates. ERIC and BOX primer sets were unable to differentiate race 3 biovar II isolates within the Kenyan population but differentiated a further two distinct profile types among the reference isolates. The race 3 biovar N2 isolate had a highly distinct RC-PFGE and repetitive sequence PCR profile. Statistical analysis of the data identified biogeographic trends consistent with conclusions drawn from previous studies on the origin and worldwide dissemination of race 3 biovar II isolates; however, genomic fingerprinting by RC-PFGE revealed a level of genetic diversity previously unrealized.  相似文献   
995.
996.
Amphipods are widely used in both acute and chronic (sub-lethal) sediment tests. Acute sediment tests provide relatively rapid results, but may fail to detect moderately toxic contaminants that are bound to the sediment, whereas chronic life-cycle tests are rarely performed as they are time consuming and expensive. Observations during chronic testing of oil-contaminated sediment suggested that there may be a link between the behavior of the marine amphipod Corophium volutator and reduction in growth rate. Behavior tests were performed with six individual amphipods per treatment using sediment spiked with weathered Forties oil with burrowing time, re-emergence from sediment, and activity prior to burrowing as endpoints. Further behavior tests were used to predict the chronic toxicity of sediments spiked with three crude oils each with a dominant unresolved complex mixture of hydrocarbons (UCM). The effect of sediment type on behavior was also investigated. The results suggested that although the behavior test could not be used alone as a viable alternative to sediment toxicity tests, it could prove useful as an adjunct to acute tests, and help select sediments that deserve further investigation.  相似文献   
997.
Although some waders (Charadrii) are known regularly to attempt to rear 2 broods in some summers (e.g. Ringed Plover Charadrius hiaticula, Little Ringed Plover Charadrius dubius l), this ability is not associated with Palearctic waders breeding at higher latitudes, except where one or more clutches are left in the sole care of previous mates. This note documents an attempt made by a male Dotterel to raise a second brood after its first brood of young became independent.  相似文献   
998.

As institutions such as the Institute for Scientific Film in Göttingen, Germany, look back on their accomplishments and look forward to what their role may be in the future, it is worthwhile to untangle some of the strands involved in the practice of “visual anthropology” and to clarify our thinking on the shared and distinctive characteristics of ethnographic films and of visual research material.  相似文献   
999.
Correlations between surface behavior and concurrent underwater vocalizations were modeled for common dolphins (Delphinus spp.) in the Southern California Bight (SCB) over multiple field seasons. Clicks, pulsed calls, and whistles were examined, with a total of 50 call features identified. Call features were used to classify behavior using random forest decision trees, with rates of correct classification reaching 80.6% for fast travel, 84.6% for moderate travel, 59.8% for slow travel, and 58% for foraging behavior. Common dolphins spent most of their time traveling. The highest number of clicks, pulsed calls, and complex whistles were produced during fast travel. In contrast, during foraging there were few pulsed calls and whistles produced, and the whistles were simple with narrow bandwidths and few harmonics. Behavior and vocalization patterns suggest nocturnal foraging in offshore waters as the primary feeding strategy. Group size and spacing were strongly correlated with behavior and rates of calling, with higher call rates in dispersed traveling groups and lower call rates in loosely aggregated foraging groups. These results demonstrate that surface behavior can be classified using vocalization data, which builds the framework for behavioral studies of common dolphins using passive acoustic monitoring techniques.  相似文献   
1000.
A mark‐resight analysis under Pollock's robust design was applied to Indo‐Pacific bottlenose dolphins Tursiops aduncus in the Swatch‐of‐No‐Ground (SoNG) submarine canyon, Bangladesh, during the winter seasons of 2005–2009. Information from sightings of photo‐identified individuals (1,144) and unmarked individuals generated abundance estimates of 1,701 (95% confidence interval [CI]= 1,533–1,888), 1,927 (95% CI = 1,851–2,006), 2,150 (95% CI = 1,906–2,425), and 2,239 (95% CI = 1,985–2,524) individuals for seasons 1–4, respectively. This makes the population among the largest assessed of the species. Overall apparent survival was estimated as 0.958 (95% CI = 0.802–0.992). Interseasonal probabilities of transitioning to an unobservable state were estimated as 0.045, 0.363, and 0.300 for years 1–2, 2–3, and 3–4, respectively, and the overall probability of remaining in an unobservable state was 0.688. These probabilities, together with an apparent increase in abundance during the study period, indicate that the identified dolphins are part of a larger superpopulation moving throughout a more extensive geographic area. Of the photo‐identified dolphins, 28.2% exhibited injuries related to entanglements with fishing gear. This implies a strong potential for fatal interactions that could jeopardize the conservation status of the population, which otherwise appears favorable.  相似文献   
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