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131.
An integrated restriction map for HindIII and EcoRI has been constructed for 386 kb of the human dystrophin-encoding gene by partial digest mapping of 35 overlapping lambda EMBL3cosW phage clones derived from a yeast artificial chromosome containing this region. Map construction was simplified in two ways. Firstly, the sequence arrangement of lambda EMBL3cosW is such that only map data from cloned inserts are generated using partial digests of lambda phage DNA asymmetrically labelled at the left cos end with a complementary 32P-labelled oligodeoxyribonucleotide. Secondly, the degree of partial digestion was standardised for each restriction enzyme by using ultraviolet light-induced formation of thymine dimers in the recognition sequence to partially block the cleavage reaction. The map provides the basis for work on the analysis of chromosomal rearrangements in this region which give rise to Duchenne muscular dystrophy, and for studies of chromosome structure and function. 相似文献
132.
PA Winstanley EK Mberu IS Szwandt AM Breckenridge WM Watkins 《Canadian Metallurgical Quarterly》1995,39(4):948-952
The potency of antimalarial dihydrofolate reductase inhibitors, alone and in synergistic combination with dihydropteroate synthetase inhibitors, against the Kenyan K39 strain of Plasmodium falciparum (pyrimethamine resistant) and against normal replicating human bone marrow cells in in vitro culture has been studied. Therapeutic indices and rank order of synergistic potency were derived. Trimethoprim, pyrimethamine, and the quinazolines WR159412 and WR158122 had the smallest therapeutic indices (1.39, 4.38, 2.56, and 90.0, respectively), while the three triazines clociguanil, WR99210, and chlorcycloguanil had the largest (3,562, 3,000, and 2,000, respectively). In rank order of decreasing activity against P. falciparum, the six most potent drug combinations were WR99210-dapsone, chlorcycloguanil-dapsone, WR158122-dapsone, WR159412-dapsone, WR159412-sulfamethoxazole, and chlorcycloguanil-sulfamethoxazole; pyrimethamine-sulfadoxine was the least potent combination. These experiments form a basis for the selection of rapidly eliminated antifolate combinations for further clinical testing. 相似文献
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135.
We have utilized whole-lung lavage in the successful treatment of 18 patients with pulmonary alveolar proteinosis. Our ten-year experience includes serial evaluations of patients with disabling lung dysfunction who had a total of 49 whole-lung lavages under general anesthesia. Clinical and physiological responses were documented both before and after each lavage. There were no complications or deaths. All patients were radiographically, physiologically, and symptomatically improved within hours after the procedures. Five patients required from two to four repeat lavages one to three years later. The treatment of this disorder has included a wide variety of techniques. We attribute our results to the use of a lung lavage technique that includes: (1) unilateral whole-lung lavages at two to three day intervals; (2) isotonic saline as the lavage solution; (3) use of a mechanical chest percussor during lavage; and (4) measuring the total thoracic compliance of each side in the immediate postlavage period as a guide for extubation. We conclude that whole-lung lavage is a safe, highly effective, repetitively applicable treatment for pulmonary alveolar proteinosis. 相似文献
136.
The paper deals with: 1. the protein concentration in the perilymph (PL), the serum and the cerebrospinal fluid (CSF), 2. the protein pattern in the PL and 3. histological findings in the middle and inner ear in unilaterally ear-infected guinea pigs. The studies were performed 6 h to 21 days post infectionem (Fig. 1). The pathological changes in the middle ear, which, in most cases, were limited to the infected ear, were initially evaluated under the operating microscope and divided into 4 stages. The analytical and histological results were presented as functions of these stages. As the inflammation intensity increased, the protein concentration in the PL of the infected ears increased to a level exceeding that of the normal value more than ten times (Fig. 2). However, in the serum and in the CSF this concentration remained unchanged. Likewise, no significant protein increase in the PL of the contralateral ears was detectable in most cases. As the inflammation intensity increased, the number of the precipitation lines detectable immunoelectrophoretically increased in the PL of the infected ears (Fig. 3). An increase in the alpha1- and gamma-globulins and a decrease in Albumin was found by electrophoresis on cellulose acetate strips (Tab. 3). The histological findings correlated with initially established inflammatory stages of the middle ear mucous membrane (Tab. 4). As the inflammation intensity increased, the round window, too, was changed pathologically, so that in some cases of purulent otitis media middle ear secretion could enter the cochlea. The protein increase in the PL immediately after the infection is probably due to an increase in the blood vessel permeability in the inner ear. 相似文献
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138.
PA Sullivan CY Soon WJ Schreurs JF Cutfield MG Shepherd 《Canadian Metallurgical Quarterly》1977,165(2):375-383
1. An improved purification was developed for L-lactate oxidase from Mycobacterium smegmatis. 2. The mol.wt. of the native enzyme by a sedimentation-equilibrium analysis was 345 000, and other ultracentrifuge methods gave values in the range 345 000-350 000. 3. An amino acid analysis, determinations of protein and flavin, a sedimentation-velocity analysis and an approach to equilibrium analysis gave values for the subunit mol.wt. in the range 43 500-47 000. 4. It was concluded that L-lactate oxidase contains eight subunits of mol.wt. 43 500. 5. Cross-linking of the subunits with dimethyl suberimidate and electron-microscopy studies were consistent with an octameric structure. 相似文献
139.
Bacteremia in a community hospital: spectrum and mortality 总被引:1,自引:0,他引:1
The problem of bacteremia was studied at our 500-bed community hospital during 1974-1975. All patients with positive blood cultures for clinically significant organisms were analyzed with respect to age, sex, host factors, type, dose, and time of institution of therapy with antibiotics, and mortality. Of 142 episodes of bacteremia, outcome according to underlying host factors showed that 12/15 died in the rapidly, fatal group, 12/24 died in the ultimately fatal group, and in the nonfatal group 25/103 died. Mortality for Gram-positive bacteremia was 37% (7/54) for Gram-negative bacteremia in the nonfatal group. In addition to underlying host factors, inappropriate antibiotic therapy also contributed to higher mortality in patients with gram-negative bacteremia. 相似文献
140.
P Mamunes PE Prince NH Thornton PA Hunt ES Hitchcock 《Canadian Metallurgical Quarterly》1976,57(5):675-680
An analysis was made of the obstetric history of 1,360 patients who were delivered in 1971. It involved 3,185 pregnancies. The aim of the study was to evaluate the risk of spontaneous termination of the pregnancy, worked out from its demographic aspect. Several ideas are worthy of consideration. The risk of spontaneous intra-uterine death is cumulative, sharply increased by a repetition of such cessation of pregnancy. The same patients often undergo intentional abortion repeatedly. The respective risks of spontaneous and provoked interruption of pregnancy have been studied in greater detail as a function of parity. 相似文献