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1.
Bidens cordylocarpa is a high polyploid species restricted in distribution to stream sides in the mountains of Jalisco, Mexico. The morphologically enigmatic species was originally described as a member of the genus Coreopsis, but later transferred to Bidens, largely because the involucral bracts appear most similar to Bidens. Characters of the cypselae, often useful in generic placement, are of no value for this species because the fruits have features not detected in either Bidens or Coreopsis. Sequences from the internal transcribed spacer region of nuclear ribosomal DNA (ITS) were used to assess the relationships of Bidens cordylocarpa. The molecular phylogeny places B. cordylocarpa in a strongly supported clade of Mexican and South American Bidens, and provides more definitive evidence of relationships than morphology, chromosome number, or secondary chemistry. Molecular, morphological, and chromosomal data suggest that B. cordylocarpa is an ancient polyploid, perhaps the remnant of a polyploid complex. Received August 28, 2000 Accepted February 11, 2001  相似文献   
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A case of chromomycosis in which hyperthermia proved effective is reported. The patient was a 56-year-old male bean curd maker who, without any previous history of minor trauma, developed on the extensor side of the left upper arm an eczematous lesion that underwent gradual radial expansion. The lesion showed a well-defined, 7×10 cm infiltrated erythematous plaque with the central area healed and, at the upper and lower borders, adherent scales and crusts on the surface. Histological examination revealed granulomatous changes in the dermis, as well as sclerotic cells within giant cells and microabscesses. On culturing,Fonsecaea pedrosoi was isolated. The patient was treated with disposable chemical pocket warmers, which were secured over the lesion with a rather tight elastic bandage, so that they kept the affected area warm for 24 hours a day. After a month of such hyperthermic treatment, the erythema and infiltration had decreased considerably, and microscopic examination and culture of the crusts both yielded negative results. Examination of biopsy specimens of the lesion after the third month showed that it had cicatrized. The treatment was stopped after 4 months, and no relapse occurred. We also summarize the published results of local hyperthermic treatment of chromomycosis in Japan.  相似文献   
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Pregnant hamsters were administered (SC) prostaglandin or vehicle on the morning of the 4th day of pregnancy. Serum progesterone was significantly depressed (p<.01) at 0.5, 2, and 6 hours after treatment with 100 μg PGF. Serum progesterone levels were unchanged 2 hours and 6 hours after treatment with 100 μg PGF and 2 hours after treatment with 1 mg PGF. Progesterone levels were depressed to less than 1 ng/ml 6 hours after treatment with 1 mg PGF. The specific uptake of 3H-PGF in whole hamster corpora lutea was significantly depressed 2 hours and 6 hours following 100 μg PGF treatment. A 15% depression in specific uptake occurred 0.5 hour post-treatment. Treatment with 100 μg PGF resulted in no change. Administration of 1 mg PGF resulted in depressed 3H-PGF uptake at both 2 and 6 hours post-treatment.Prostacyclin (PGI2) treatment resulted in no change in either 3H-PGF specific uptake or serum progesterone 2 hours after 100 μg treatment SC. These parameters were both reduced approximately 30% 6 hours post-treatment. Treatment with 6-keto-PGF resulted in a complete lack of measurable 3H-PGF uptake and serum progesterone levels less than 1 ng/ml at both 2 and 6 hours after treatment with 1 mg SC.  相似文献   
5.
The HLA class I antigen B44 is found in each of two different extended major histocompatibility haplotypes (allele combinations of HLA-B, HLA-DR, and complement genes BF, C2, C4A, and C4B in linkage disequilibrium). Using isoelectric focusing, two variants of HLA-B44 were identified. The basic variant was found in all cell lines with the extended haplotype HLA-B44, DR7, FC31, and the acidic variant in all cell lines with the extended haplotype HLA-B44, DR4, SC30. The occurrence of each antigen variant with a unique extended haplotype explains previous observations concerning the nonrandom association of B44 variants with DR antigens.  相似文献   
6.
The DNA-binding domain of Epstein-Barr virus nuclear antigen 1 was found by hydroxyl radical footprinting to protect backbone positions on one side of its DNA-binding site. The guanines contacted in the major groove by the DNA-binding domain of Epstein-Barr virus nuclear antigen 1 were identified by methylation protection. No difference was found in the interaction of the DNA-binding domain of Epstein-Barr virus nuclear antigen 1 with tandemly repeated and overlapping binding sites.  相似文献   
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Some evidence indicates that photosynthetic rate (A) and stomatal conductance (g) of leaves are correlated across diverse environments. The correlation between A and g has led to the postulation of a “messenger” from the mesophyll that directs stomatal behavior. Because A is a function of intercellular CO2 concentration (ci), which is in turn a function of g, such a correlation may be partially mediated by ci if g is to some degree an independent variable. Among individual sunlit leaves in a cotton (Gossypium hirsutum L.) canopy in the field, A was significantly correlated with g (r2 = 0.41, n = 63). The relative photosynthetic capacity of each leaf was calculated as a measure of mesophyll properties independent of ci. This approach revealed that, in the absence of ci effects, mesophyll photosynthetic capacity was unrelated to g (r2 = 0.06). When plants were grown in an atmosphere enriched to about 650 microliters per liter of CO2, however, photosynthetic capacity remained strongly correlated with g even though the procedure discounted any effect of variable ci. This “residual” correlation implies the existence of a messenger in CO2-enriched plants. Enriched CO2 also greatly increased stomatal response to abscisic acid (ABA) injected into intact leaves. The data provide no evidence for a messenger to coordinate g with A at ambient levels of CO2. In a CO2-enriched atmosphere, though, ABA may function as such a messenger because the sensitivity of the system to ABA is enhanced.  相似文献   
8.
Paracoccidioidomycosis was induced in immunized (IM) and non-immunized (NI) mice. The histopathology, the number of fungi in the lungs, the cellular (footpad test — FPT and macrophage inhibition factor assay — MIF) and humoral (immunodiffusion test) immune response were investigated serially postinfection. In the IM mice, at days 1 and 3, there was intense and predominant macrophagic-lymphocytic alveolitis with loose granulomatous reaction; at day 30, inflammation was mild. In the NI group, up to day 3, the lesions were focal; later there was formation of extensive epithelioid granuloma. The number of fungi in IM mice were always smaller than those of NI group. Immunization alone induced positive FPT and MIF indices with low titer of antibody. After infection, there was a significant decrease of the FPT indices in the IM group, which we interpreted as desensitization due to trapping of sensitized lymphocytes in the lungs. In conclusion, (1) The lesional pattern of pulmonary paracoccidioidomycosis in IM mice was similar to that of a hypersensitivity pneumonitis. This reaction was probably effective in reducing the extension of the infection and decrease the number of fungi. (2) In this model, pulmonary resistance against P. brasiliensis seems to be related to local and systemic delayed-type hypersensitivity reaction.  相似文献   
9.
The present study was designed to evaluate the effects of a recombinant human G-CSF (rhG-CSF) and a mutein G-CSF(KW-2228) on leucopenia and tumor growth in mice treated with 5-fluorouracil (5-FU). In normal mice, the number of leucocytes (white blood cell, WBC) reached the peak 12 hours after a single injection of either type of G-CSF and decreased to the normal level after 24 hours. Daily administration induced a continuous increase in the WBC count, however, administrations at intervals did not. Meth-A fibrosarcoma was subcutaneously inoculated into the backs of syngeneic BALB/c mice. The mice were treated with 5-FU alone or with G-CSFs. Chemotherapy with 5-FU alone resulted in leucopenia and an insignificant inhibition of tumor growth. The conjunctive administration of G-CSFs with 5-FU resulted in a significantly augmented inhibition of tumor growth, and leukopenia was not seen. This augmenting effect was more prominent with KW-2228.These results suggest that in 5-FU chemotherapy G-CSFs may be beneficial in restoring the number of leucocytes from leucopenic state and in augmenting the tumor inhibitory effect. Furthermore, KW-2228 may be more beneficial than the natural type rhG-CSF.  相似文献   
10.
The immunoglobulins of the bullfrog Rana catesbeiana are unusual in that, in all classes, the light chains are not disulfide bonded to heavy chains or to other light chains. Moreover, the light chains contain six, rather than the usual five, residues of half-cystine. As none of these half-cystines is in the sulfhydryl form or is alkylated after mild reduction, we suggested that the light chains probably contain three intrachain disulfide bridges. We have now carried out experiments to confirm the existence of an extra intrachain disulfide bridge in Rana catesbeiana light chains and to determine its location. Disulfide bridge assignments were based on 1) isolation and sequence analysis of S-(carboxymethyl)cysteine-containing peptides and 2) isolation, from unreduced light chains, of peptides containing a disulfide bridge. Half-cystine residues were found at positions 134 and 194, and these were shown to be joined in the conserved intradomain disulfide bridge. In addition, we found that a residue of half-cystine, located at the third position from the carboxy-terminus, forms a disulfide bridge with a half-cystine at position 119, near the amino-terminus of the domain, the latter residue replacing a proline that has been found at this position in all other light chains. An intrachain disulfide bridge has not been found at this location in any other light chain.  相似文献   
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