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111.
Conjugation of carboxypeptidase G and arginase, two enzymes of therapeutic interest, to a soluble dextran significantly enhanced plasma persistence in normal and tumour-bearing mice. A prolonged decrease in arginine concentrations in plasma of tumour-bearing mice was demonstrated by using the dextran-linked arginase. Gel filtration of dextran-enzyme conjugate showed that enzyme activity co-chromatographed as a single peak with carbohydrate, and enzyme was shown to be covalently linked to the dextran.  相似文献   
112.
A clinically malignant tongue ulcer in a 63-year-old White man was proved by histological examination and culture to be due to Blastomyces dermatitidis. In addition, pulmonary lesions caused by B. dermatitidis were found at autopsy.  相似文献   
113.
The bactericidal actions of ofloxacin and sulbactam-ampicillin, alone and in combination with rifampin and isoniazid, on exponential-phase and stationary-phase cultures of a drug-susceptible isolate of Mycobacterium tuberculosis were studied in vitro. In exponential-phase cultures, all drugs were bactericidal, with the higher concentrations of ofloxacin (5 micrograms/ml) and sulbactam-ampicillin (15 micrograms of ampicillin per ml) being as bactericidal as 1 microgram of isoniazid per ml or 1 microgram of rifampin per ml. In two-drug combinations, both drugs increased the levels of activity of isoniazid and rifampin and were almost as bactericidal as isoniazid-rifampin; they also appeared to increase the level of activity of isoniazid-rifampin in three-drug combinations. In contrast, ofloxacin and sulbactam-ampicillin had little bactericidal activity against stationary-phase cultures and were less active than isoniazid or rifampin alone. Furthermore, in two-drug or three-drug combinations, they did not increase the level of activity of isoniazid, rifampin, or isoniazid-rifampin. These findings suggest that ofloxacin and sulbactam-ampicillin are likely to be most useful in the early stages of treatment and in preventing the emergence of resistance to other drugs but are unlikely to be effective as sterilizing drugs helping to kill persisting lesional bacilli.  相似文献   
114.
Increased levels of the endothelial markers soluble E-selectin (P = 0.011), soluble thrombomodulin (P < 0.0001) and von Willebrand factor (VWF, P < 0.0001) were found in 116 patients with ischaemic heart disease compared to an equal number of age- and sex-matched asymptomatic controls. In a multivariate analysis of the markers versus the major risk factors for atherosclerosis, VWF correlated with total cholesterol (P = 0.002) and E-selectin with sex (lower in women, P = 0.004) and triglycerides (P = 0.007). The data point to profound differences in the release mechanisms of these three endothelial cell products and suggests that further studies into the roles of these molecules in coronary artery disease are warranted.  相似文献   
115.
NGN网络业务NAT穿透技术探讨   总被引:1,自引:0,他引:1  
严军 《世界电信》2003,16(11):42-47
主要参考IETF关于NGN网络中会话业务穿透NAT技术的各种草案,介绍了目前业务开展可以使用的几种NAT穿透技术和方案.并对几种技术方案结合网络的实际情况进行了对比和分析.最后给出了华为公司对NGN业务穿透NAT的解决方案建议。  相似文献   
116.
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118.
    
CN Gutt  S Held  V Paolucci  A Encke 《Canadian Metallurgical Quarterly》1996,20(8):1006-8; discussion 1108-9
Today the procedure of choice for long-term enteral tube feeding in patients with prolonged swallowing difficulties or inabilities is percutaneous endoscopic gastrostomy (PEG). The primary indications are head and neck cancers, neurologic dysphagia, cancer cachexia, and obstruction of the esophagus and pharynx with enough space for an endoscopic procedure. This technique requires no general anesthesia and is possible in patients with contraindications to surgical gastrostomy. Between September 1994 and April 1995 a total of 115 patients underwent PEG placement attempts. We employed the pull-technique with 15-Freka PEG tubes. The average procedure time, including esophagogastroduodenoscopy, was 17 minutes. In nine cases PEG insertion was impossible owing to severe obstruction of the esophagus. In 46 (40%) patients local abdominal pains started on the first or second postoperative day; 7 of these patients required surgical consultation, and no further intervention was needed. In only one patient was there a serious complication that required surgical intervention: a presumed perforation that turned out to have no correlate upon review. All patients received single-shot antibiotic prophylaxis; and only in those patients with abdominal symptoms do we recommend a prolonged antibiosis. The abdominal symptoms reported were due to a slight leak of gastric fluid causing a topical peritonitis, which required no further treatment. In our experience PEG is a useful alternative to surgical gastrostomy. The simplicity of this procedure leads to low complication rates, short hospitalization, and is possible on an outpatient basis. It is cost-efficient and has a much better psychological tolerance than nasogastric tubes.  相似文献   
119.
Ventilatory management of patients with acute lung injury (ALI), particularly its most severe subset, acute respiratory distress syndrome (ARDS), is complex. Newer lung protective strategies emphasize measures to enhance alveolar recruitment and avoid alveolar overdistention, thus minimizing the risk of ventilator-induced lung injury (VILI). Key components of such strategies include the use of smaller-than-conventional tidal volumes which maintain peak transpulmonary pressure below the pressure associated with overdistention, and titration of positive end-expiratory pressure to promote maximal alveolar recruitment. Novel techniques, including prone positioning, inverse ratio ventilation, tracheal gas insufflation, and high frequency ventilation, are considerations in severe ARDS. No single approach is best for all patients; adjustment of ventilatory parameters to individual characteristics, such as lung mechanics and gas exchange, is required.  相似文献   
120.
To elucidate the germline RET proto-oncogene mutations in Taiwanese families with multiple endocrine neoplasia type 2A (MEN 2A), we extracted DNA from peripheral blood leukocytes of 28 members of two families with MEN 2A. Oligonucleotide primers for exons 10 and 11 were used to analyze the nucleotide sequence of codons 609, 611, 618, and 620 of exon 10, and codon 634 of exon 11 of the RET proto-oncogene. Two fragments of genomic DNA were amplified by polymerase chain reaction (PCR). The amplified PCR products were separated and purified from primers and free nucleotides in agarose gels, and the expected 187-bp and 234-bp bands were cut from the gels and sequenced. Thirteen family members in the two MEN 2A kindreds had mutations in codon 634 of exon 11. In kindred 1 (15 members available for this study), a heterozygous codon 634 mutation in nine members and a homozygous codon 634 mutation in one member led to the substitution of Phe (TTC) for Cys (TGC). Three members of kindred 2 (13 members available for this study) had a heterozygous base pair change in codon 634, which led to the substitution of Arg (CGC) for Cys (TGC). In this study, we found two mutation events occurring in two MEN 2A kindreds and also discovered a homozygous point mutation in one woman that led to heterozygous mutations in all of her children.  相似文献   
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