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1.
D R Dubbs  H Otsuka  H Qavi  S Kit 《Virology》1983,126(1):408-411
Five hybrid plasmids were constructed, each containing a portion of the vaccinia virus DNA HindIII-J fragment. These plasmid DNAs were used in marker rescue experiments to map the mutations in the thymidine kinase (TK) gene of three TK- vaccinia virus mutants. The TK gene of each of the three mutants was rescued by DNA from plasmid pPJ701, which contained about one-half of the HindIII-J fragment. Two mutants, 1004B and 1017-1, but not the third, 1016-1, were rescued by DNA of two plasmids, pPJ702 and pPJ703, which contained 16 and 18%, respectively, of one end of the J fragment. Mutant 1016-1 could be rescued by plasmid pPJ705 containing a 1.69-kb fragment of the HindIII-J fragment. The J fragment DNA in plasmid pPJ705 is located adjacent to that and separated by an EcoRI site from pPJ703 in the vaccinia virus genome. These results indicate that the mutation site in the TK gene of 1016-1 differs from that in 1004B or 1017-1 and suggests that the structural gene for the vaccinia virus TK lies near one end of the HindIII-J fragment and spans the EcoRI site.  相似文献   
2.
Summary Based upon findings from 60 cadavers (120 sides), the incidence of superior laryngeal nerve loop, connecting the cervical sympathetic chain and the superior laryngeal nerve and its branches, the external and internal laryngeal nerve, was 98.3% (118 out of 120 sides). In most cases the loop connected the sympathetic chain and the external laryngeal nerve. The external laryngeal nerve was looped, and not linear as traditionally thought. The loop could be divided into three categories, V-shaped, U-shaped and mixed, and subdivided into 5 types and 17 subtypes according to morphological variation. The loop without exception innervated not only the cricothyroid muscle, but also the thyroid gland. The loop is one of the origins of the thyroid nerve. It seems that for thyroid surgery the loop, when lower in position, should be carefully separated from the superior thyroid vessels before the latter are ligated, in order to preserve a normal nerve supply to the muscle as well as to the part of the gland that remains after surgery.
L'anse du nerf larynge supérieur, étude anatomique et applications chirurgicales
Résumé La fréquence d'une anse du nerf laryngé supérieur réalisant une anastomose entre la chaine sympathique cervicale et le nerf laryngé supérieur et/ou ses branches (rameau laryngé externe et ingerne), est de 98,3 % (118/120). Ce résultat s'appuie sur l'étude de 60 cadavres. Dans la plupart des cas, l'anastomose se fait entre la chaine sympathique cervicale et le rameau laryngé externe. Ce rameau laryngé externe a un trajet curviligne et non linéaire conformément aux données classiques. Il existe trois catégories d'anses : en "V", en "U" et mixte ; on peut également les subdiviser en 5 types et 17 sous-types en fonction des variations morphologiques. Cette anse innerve constamment non seulement le muscle cricothyroïdien mais aussi la glande thyroïde dont elle fournit une partie de l'innervation. Lors de la chirurgie thyroïdienne, si l'anse est en position basse, les nerfs doivent être soigneusement disséqués et séparés des vaisseaux thyroïdiens supérieurs avant ligature de ces derniers de façon à conserver l'innervation normale du muscle et de la partie restante de la glande.
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3.
The mammary gland is a hormone-target organ derived from epidermis and develops as a result of reciprocal mesenchymal-epithelial interactions. The induction of mammary differentiation from indifferent epidermal cells by mammary mesenchyme implies induction of the complement of hormone receptors characteristic of normal mammary epithelium in cells of the epidermis. Considering the facts that mammary epithelial differentiation is induced by mammary mesenchyme and that certain aspects of hormone response (androgen-induced mammary regression) are inextricably linked to mesenchymal-epithelial interactions, it is evident that the biology of the mammary gland arises from and is maintained via cell-cell interactions. As a corollary, perturbation of stromal-epithelial interactions in adulthood may play a role in mammary carcinogenesis and in turn may provide opportunities for differentiation therapy.  相似文献   
4.
Polymorphisms in the promoter of the BRM gene, a critical subunit of the chromatin remodeling SWI/SNF complex, have previously been implicated in risk and prognosis in Caucasian‐predominant lung, head and neck, esophageal, and pancreatic cancers, and in hepatocellular cancers in Asians. We investigated the role of these polymorphisms in hepatocellular carcinoma (HCC) risk and prognosis. HCC cases were recruited in a comprehensive cancer center while the matched controls were recruited from family practice units from the same catchment area. For risk analyses, unconditional logistic regression analyses were performed in HCC patients and matched healthy controls. Overall survival analyses were performed using Cox proportional hazard models, Kaplan‐Meier curves, and log‐rank tests. In 266 HCC cases and 536 controls, no association between either BRM promoter polymorphism (BRM‐741 or BRM‐1321) and risk of HCC was identified (P > 0.10 for all comparisons). There was significant worsening of overall survival as the number of variant alleles increased: BRM‐741 per variant allele adjusted hazards ratio (aHR) 5.77, 95% confidence interval (CI) 2.89‐11.54 and BRM‐1321 per variant allele aHR 4.09, 95%CI 2.22‐7.51. The effects of these two polymorphisms were at least additive, where individuals who were double homozygotes for the variant alleles had a 45‐fold increase in risk of death when compared to those who were double wild‐type for the two polymorphisms. Two BRM promoter polymorphisms were strongly associated with HCC prognosis but were not associated with increased HCC susceptibility. The association was strongest in double homozygotes for the allele variants.  相似文献   
5.
Evidence supporting the impact of therapeutic zinc supplementation on the duration and severity of diarrhea among children under five is largely derived from studies conducted in South Asia. China experiences a substantial portion of the global burden of diarrhea, but the impact of zinc treatment among children under five has not been well documented by previously published systematic reviews on the topic. We therefore conducted a systematic literature review, which included an exhaustive search of the Chinese literature, in an effort to update previously published estimates of the effect of therapeutic zinc. We conducted systematic literature searches in various databases, including the China National Knowledge Infrastructure (CNKI), and abstracted relevant data from studies meeting our inclusion and exclusion criteria. We used STATA 12.0 to pool select outcomes and to generate estimates of percentage difference and relative risk comparing outcomes between zinc and control groups. We identified 89 Chinese and 15 non-Chinese studies for the review, including studies in 10 countries from all WHO geographic regions, and analyzed a total of 18,822 diarrhea cases (9469 zinc and 9353 control). None of the included Chinese studies had previously been included in published pooled effect estimates. Chinese and non-Chinese studies reported the effect of therapeutic zinc supplementation on decreased episode duration, stool output, stool frequency, hospitalization duration and proportion of episodes lasting beyond three and seven days. Pooling Chinese and non-Chinese studies yielded an overall 26% (95% CI: 20%−32%) reduction in the estimated relative risk of diarrhea lasting beyond three days among zinc-treated children. Studies conducted in and outside China report reductions in morbidity as a result of oral therapeutic zinc supplementation for acute diarrhea among children under five years of age. The WHO recommendation for zinc treatment of diarrhea episodes should be supported in all low- and middle-income countries.  相似文献   
6.
7.
The intervertebral disks along the spine provide motion and protection against mechanical loading. The 3 structural components, nucleus pulposus, annulus fibrosus, and cartilage endplate, function as a synergistic unit, though each has its own role. The cells within each of these components have distinct origins in development and morphology, producing specific extracellular matrix proteins that are organized into unique architectures fit for intervertebral disk function. This article focuses on various aspects of intervertebral disk biology and disruptions that could lead to diseases such as intervertebral disk degeneration.  相似文献   
8.
Wong RK  Poon ES  Woo CY  Chan SC  Wong ES  Chu AW 《Head & neck》2007,29(8):758-764
BACKGROUND: We sought to determine the major factors affecting speech production of Cantonese-speaking glossectomized patients. Error pattern was analyzed. METHODS: Forty-one Cantonese-speaking subjects who had undergone glossectomy > or = 6 months previously were recruited. Speech production evaluation included (1) phonetic error analysis in nonsense syllable; (2) speech intelligibility in sentences evaluated by naive listeners; (3) overall speech intelligibility in conversation evaluated by experienced speech therapists. RESULTS: Patients receiving adjuvant radiotherapy had significantly poorer segmental and connected speech production. Total or subtotal glossectomy also resulted in poor speech outcomes. Patients having free flap reconstruction showed the best speech outcomes. Patients without lymph node metastasis had significantly better speech scores when compared with patients with lymph node metastasis. Initial consonant production had the worst scores, while vowel production was the least affected. CONCLUSION: Speech outcomes of Cantonese-speaking glossectomized patients depended on the severity of the disease. Initial consonants had the greatest effect on speech intelligibility.  相似文献   
9.
End‐stage renal failure is associated with persistent systemic inflammation. The aim of this study was to investigate if systemic inflammation at the time of kidney transplantation is linked to poor graft survival, major adverse cardiovascular events (MACE), and increased mortality, and if these processes are modulated by naturally occurring cytokine‐specific autoantibodies (c‐aAbs), which have been shown to regulate cytokine activity in vitro. Serum levels of cytokines, high‐sensitivity C‐reactive protein (hsCRP) and c‐aAbs specific for interleukin (IL)‐1α, tumor necrosis factor (TNF)‐α, IL‐6, and IL‐10 were measured at the time of transplantation in a retrospective cohort study of 619 kidney transplanted patients with a median follow‐up of 4.9 years (range 1.2–8.2 years). Systemic inflammation was associated with all‐cause mortality in simple and multiple Cox regression analyses. IL‐10‐specific c‐aAbs were associated with MACE after transplantation, suggesting that IL‐10 may be a protective factor. Similarly, patients with a history of MACE before transplantation had lower levels of TNF‐α‐specific c‐aAbs, hence we hypothesized that TNF may be a risk factor of MACE. These findings support that pro‐inflammatory activity before transplantation is a pathological driver of MACE and all‐cause mortality after transplantation. This information adds to pretransplantation risk estimation in renal transplant candidates.  相似文献   
10.
Aim: To examine the influence of diabetes mellitus (DM) on the outcome of infrainguinal bypass operations performed for critical foot ischaemia in Chinese patients. Methods: A prospective audit of 265 consecutive infrainguinal bypass operations. Results: Diabetic patients suffered more frequently from ischaemic heart disease (48%vs 25%, P= 0.001) and tissue loss (90%vs 79%, P = 0.01) at presentation. Cigarette smoking was more prevalent in the non‐diabetic (NDM) group (72%vs 51%, P = 0.001). Arterial segments distal to the common femoral artery were more often used as inflow to bypass graft in DM patients (36%vs 22%, P = 0.02). Operative mortality (seven DM vs one NDM, P = 0.19). Early graft failure (7% in DM group vs 10% in NDM group, P = 0.24), wound infection rate (24% in DM group vs 17% in NDM group, P = 0.21), early limb loss (9% in DM group vs 6% in NDM group, P = 0.66) were comparable. However, hospital mortality was higher in DM patients (8%vs 1%, P = 0.04). DM patients more frequently required further surgical debridement postoperatively (20%vs 9%, P = 0.04). Long‐term, patient survival was inferior in the DM group (43% NDM vs 33% DM at 5 years, P = 0.03). Primary graft patency (46% DM vs 34% NDM at 4 years P = 0.19), secondary graft patency (57% DM vs 47% NDM at 4 years P = 0.14) and limb salvage rate (78%vs 81% at 5 years, P = 0.79) were comparable. Conclusion: Diabetes mellitus adversely affects hospital mortality and long‐term survival. Graft patency and limb salvage are not compromised by the presence of DM.  相似文献   
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