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61.
Background: Stress fracture is the single most common cause for the lost number of manpower days during training. The conventional treatment options begin with rest and cessation of precipitating activity. However the demands of military training provide little tolerance for prolonged periods of rest. In the recent past ultrasound therapy (UST) has been reported to speed up healing of stress fractures.  相似文献   
62.
目的:将中药黄芪载入胶原支架内,通过对胶原支架进行修饰,观察黄芪能否代替生长因子起到促进血管生成疗效,并了解黄芪与生长因子是否有协同作用. 方法:实验于2004-07-01/2006-07-01在德国亚琛工业大学生化研究所及江苏省中医院中心实验室进行.首先通过不同的EDC/NHS与肝素钠比例来交链修饰Ⅰ型胶原(EDC与NHS质量比固定为1∶0.6,EDC与肝素钠比例为0.2~4),然后将1 mL黄芪注射液(相当于3 mg生药黄芪)载入修饰后的胶原内.体外通过甲苯胺蓝法测定修饰后胶原内肝素含量,胶原酶降解法测量胶原体外降解率,同时对胶原的亲水性及自由氨基团进行测定.体内通过鸡胚绒毛尿囊膜模型进行血管计数及血红蛋白测定. 结果:①体外实验结果:通过对胶原的修饰程度,可以控制胶原内的肝素含量、体外降解率、自由氨基团含量、亲水性大小.②体内实验结果:黄芪注射液1 mL载入修饰后的胶原较载入未修饰的胶原,可以明显促进鸡胚绒毛尿囊膜内微血管生成,提高胶原内血红蛋白含量(P<0.01),其疗效与重组人体血管内皮生长因子载入修饰后的胶原内相当,且与血管内皮生长因子有协同作用的趋势. 结论:通过对胶原的修饰来控制胶原的体外降解,载入黄芪后,使黄芪促血管生成疗效增强,达到与血管内皮生长因子载入后的疗效相当,其作用机制有待进一步研究.  相似文献   
63.
High-density single-nucleotide polymorphism (SNP) genotyping technology enables extensive genotyping as well as the detection of increasingly smaller chromosomal aberrations. In this study, we assess molecular karyotyping as first-round analysis of patients with mental retardation and/or multiple congenital abnormalities (MR/MCA). We used different commercially available SNP array platforms, the Affymetrix GeneChip 262K NspI, the Genechip 238K StyI, the Illumina HumanHap 300 and HumanCNV 370 BeadChip, to detect copy number variants (CNVs) in 318 patients with unexplained MR/MCA. We found abnormalities in 22.6% of the patients, including six CNVs that overlap known microdeletion/duplication syndromes, eight CNVs that overlap recently described syndromes, 63 potentially pathogenic CNVs (in 52 patients), four large segments of homozygosity and two mosaic trisomies for an entire chromosome. This study shows that high-density SNP array analysis reveals a much higher diagnostic yield as that of conventional karyotyping. SNP arrays have the potential to detect CNVs, mosaics, uniparental disomies and loss of heterozygosity in one experiment. We, therefore, propose a novel diagnostic approach to all MR/MCA patients by first analyzing every patient with an SNP array instead of conventional karyotyping.  相似文献   
64.
Introduction: Laparoscopic cholecystectomy has been the standard of care for gallbladder diseases since the late 1980s. Many surgeons have rapidly adopted single‐port laparoscopic cholecystectomy for gallbladder pathologies. The aim of the present study was to analyze the clinical outcome in initial single‐port laparoscopic cholecystectomy. Methods: Data from 106 consecutive single‐port laparoscopic cholecystectomies between May 2008 and April 2009 were analyzed retrospectively. We divided the patients into two groups – an early group (group I, n=56) and a late group (group II, n=50) – to compare clinical outcomes. During each procedure, only one longitudinal transumbilical incision, 1.5 to 2.0 cm in length, was made to access the abdominal cavity. A multichannel port system was assembled with existing devices. Standard laparoscopic instruments were used to perform each cholecystectomy. Results: Patient demographics did not differ between the two groups. Of the eight cases that were converted to conventional laparoscopic surgery, seven were part of group I (P=0.063). Mean operation time for single‐port laparoscopic cholecystectomy was significantly shorter in group II (58.2 versus 71.6 min, P=0.004). There were two operative complications in group I, which were successfully managed with laparoscopic surgery. There was no statistical difference in occurrence of operative complication and hospital stay between the two groups. Conclusion: Single‐port laparoscopic cholecystectomy can be safely performed for various gallbladder lesions in selected cases, and the operation time improved with accumulation of cases.  相似文献   
65.
In Plasmodium falciparum, the causative agent of cerebral malaria, silent information regulator 2 (Sir2) has been implicated in pathogenesis through its role in var gene silencing. P. falciparum Sir2 (PfSir2) in addition to the catalytic core, has a 13 residue N-terminal and 4 residue C-terminal extension over the shorter Archaeoglobus fulgidus Sir2. In this paper, we highlight our studies aimed at understanding the kinetic mechanism of PfSir2 and the role of N- and C-terminal extensions in protein function and oligomerization. Bisubstrate kinetic analysis showed that PfSir2 exhibits a rapid equilibrium ordered sequential mechanism, with peptide binding preceding NAD(+). This study also reports on surfactin as a novel Sir2 inhibitor exhibiting competitive inhibition with respect to NAD(+) and uncompetitive inhibition with acetylated peptide. This inhibition pattern with surfactin provides further support for ordered binding of substrates. Surfactin was also found to be a potent inhibitor of intra-erythrocytic growth of P. falciparum with 50% inhibitory concentration in the low micromolar range. PfSir2, like the yeast homologs (yHst2 and Sir2p), is a trimer in solution. However, dissociation of trimer to monomers in the presence of NAD(+) is characteristic of the parasite enzyme. Oligomerization studies on N- and/or C-terminal deletion constructs of PfSir2 highlight the role of C-terminus of the protein in mediating homotrimerization. N-terminal deletion resulted in reduced catalytic efficiency although substrate affinity was not altered in the constructs. Interestingly, deletion of both the ends relaxed NAD(+) specificity.  相似文献   
66.
Measurement of P-glycoprotein and the gene that encodes it, mdr-1, is an important tool for assessing the impact of multidrug resistance in clinical cancer. We evaluated mdr-1 expression by a quantitative polymerase chain reaction (PCR) assay in 78 biopsy samples from 48 patients with refractory lymphoma enrolled on a trial of infusional chemotherapy (EPOCH) in which R-verapamil was added as an antagonist of P-glycoprotein in a subset of patients whose tumors were unresponsive to treatment. Expression of mdr-1 was detectable in all biopsies at the time of enrollment on study, and a fourfold or greater increase in mdr- 1 expression was noted in 42% of patients at the time of treatment failure. Expression of mdr-1 was also detectable in biopsies from patients at the time of diagnosis of lymphoma. An endogenous control gene, beta 2-microglobulin, was quantitated for normalization of the mdr-1 values. The use of beta 2-microglobulin expression for normalization was validated in a subset of samples by comparing Northern blots detecting beta 2-microglobulin, beta actin, and GAPDH gene expression. Immunoblot analysis suggested that no major discrepancy was present between mRNA expression and protein level. Immunophenotyping of lymphomatous lymph nodes showed that infiltration of tumor cells ranged from 8% to 95% and of normal T cells from 1% to 83%. Expression of mdr-1 in normal T cells and monocytes was also shown to be low. The mdr-1 levels in patient samples were independent of T- cell contamination, suggesting that the presence of normal cells has at best a small impact on mdr-1 measurements. Expression of mdr-1 in lymphoma can be quantitated by PCR, and wide variations in expression can be observed. Increased expression in patients with refractory disease supports an important role for Pgp in drug resistance in lymphoma. These studies will aid in the design and interpretation of clinical trials in lymphoma.  相似文献   
67.
Narcolepsy is a chronic condition that usually afflicts the patient for decades. It is more common than is generally appreciated. However, it is likely to be misdiagnosed because doctors are unfamiliar with some of the symptoms. Its significant socioeconomic impact on the patient's quality of life warrants prompt medical attention.  相似文献   
68.
69.
司伊康  郑多楷  黄量 《药学学报》1990,25(6):423-429
本文报道消旋棉酚与15种不同结构的光学活性胺缩合产物的薄层色谱性质和核磁共振氢谱数据,以及8个光学活性胺与光学活性棉酚缩合物的光学稳定性,并探讨了结构与这些性质的关系。  相似文献   
70.

Background

Tuberculin skin testing (TST) is a reliable tool in the diagnosis of tuberculous infection and is important in its control. However, it may be false negative in immunocompromised patients like HIV-infected.

Methods

We examined the pattern of TST results in 523 newly diagnosed HIV-positive patients. CD4, CD8 and absolute lymphocyte counts were done by flowcytometry in 63 of these cases.

Results

56 (44.10%), 15 (11.81%) and 56 (44.10%) of the 127 cases with tuberculosis and 293 (73.99%), 41 (10.35%) and 62 (15.66%) of the 396 cases without any clinical evidence of tuberculosis showed TST results of 0-4, 5-9 and = or > 10 mm respectively. Significantly more (P<0.05) number of cases with TST of = or > 10mm and significantly lesser (P<0.05) number of cases with TST of 0-4 mm are likely to develop tuberculosis. The average CD4+lymphocyte count was found to be significantly lower in cases with nil TST results than with = or >10mm. HIV infected cases associated with tuberculosis with induration on TST had average CD4 counts of 129.5 as compared to 246.3/cmm in those without tuberculosis.

Conclusion

In India where both these diseases are endemic, tuberculosis may develop during early HIV infection, while the body''s immunity is still largely unimpaired and TST shows = or >10mm results in almost 45% of our cases. In another 45% with TST of 0-4mm, the CD4+ lymphocyte count is likely to be lower than 200/cmm. In those with nil induration, TST of 5-9 mm cannot be taken as an independent marker for suspecting tuberculosis in the HIV infected. Hence we recommend that all cases with TST of = or >10mm and cases with nil induratrion with CD4+ count of <200/cmm should be considered as high-risk for developing tuberculosis.Key Words: Tuberculin skin test, HIV infection  相似文献   
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