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111.
Due to an increase in bovine tuberculosis in cattle in the United Kingdom, we investigated the characteristics of Mycobacterium bovis infection in humans and assessed whether extensive transmission of M. bovis between humans has occurred. A cross-sectional study linking demographic, clinical, and DNA fingerprinting (using 15-locus mycobacterial interspersed repetitive-unit-variable-number tandem-repeat [MIRU-VNTR] typing) data on cases reported between 2005 and 2008 was undertaken. A total of 129 cases of M. bovis infection in humans were reported over the period, with a decrease in annual incidence from 0.065 to 0.047 cases per 100,000 persons. Most patients were born pre-1960, before widespread pasteurization was introduced (73%), were of white ethnicity (83%), and were born in the United Kingdom (76%). A total of 102 patients (79%) had MIRU-VNTR typing data. A total of 31 of 69 complete MIRU-VNTR profiles formed eight distinct clusters. The overall clustering proportion determined using the n - 1 method was 33%. The largest cluster, comprising 12 cases, was indistinguishable from a previously reported West Midlands outbreak strain cluster and included those cases. This cluster was heterogeneous, having characteristics supporting recent zoonotic and human-to-human transmission as well as reactivation of latent disease. Seven other, smaller clusters identified had demographics supporting recrudescence rather than recent infection. A total of 33 patients had incomplete MIRU-VNTR profiles, of which 11 may have yielded 2 to 6 further small clusters if typed to completion. The incidence of M. bovis in humans in the United Kingdom remains low, and the epidemiology is predominantly that of reactivated disease.  相似文献   
112.
113.

Objectives

The aim of this study was to determine day 3 Serum AMH, FSH, LH, Estradiol (E2), Inhibin B levels, ovarian volume, and antral follicular count to assess ovarian function.

Methods

This study was conducted on 130 infertile women between age 18 and 43 years. Day 3 Serum AMH level was estimated by sandwich enzyme immunoassay; Serum FSH, S. LH, S. E2, by solid-phase two-site chemiluminescent immunometric assay; Inhibin B by ELISA; and Ovarian volume and AFC, by transvaginal ultrasonography.

Results

With advancing age, Serum AMH level (p < 0.0001), AFC (p < 0.05), ovarian volume (>0.05), and Inhibin B (>0.05) were decreased, and Serum FSH (p < 0.05), LH (p > 0.05), and E2 (p < 0.05) were increased. Serum AMH level was 4–6.8 ng/ml with optimal fertility in 26.15 % cases and 2.2–4.0 ng/ml with satisfactory fertility in 53.85 % cases. Serum AMH levels were more strongly correlated with AFC (p < 0.0001) and ovarian volume (p < 0.0001).

Conclusion

Serum AMH levels were more robustly correlated with AFC than FSH, LH, E2, and Inhibin B on day 3 of the cycle. This suggested that serum AMH might be taken as single test to reflect ovarian reserve.  相似文献   
114.
Biodegradable microcapsules of pentamidine/poly(L-lactide-co-D,L-lactide) were prepared by solvent evaporation technique using a mixture of organic solvents. The control batch of microcapsules was prepared using dichloromethane. The effect of solvent on the characteristics of pentamidine loaded microcapsules was examined by substituting up to 30% of dichloromethane with acetone, methanol, DMSO, ethyl acetate, and ethanol, respectively. No significant change in the surface morphology was observed when dichloromethane was substituted with 20% or less amount of other solvents. These microcapsules were all porous and spherical. However, the use of 30% DMSO or ethanol, along with dichloromethane, resulted in a mixture of elongated and spherical microcapsules. The efficiency of encapsulation of these two batches was also significantly higher than the other batches of microcapsules. The average particle size of the microcapsules prepared with 30% DMSO (165 microm) was significantly higher than the other batches (< 80 microm). A substitution of 10-30% dichloromethane with other listed organic solvents also showed a significant difference in the initial drug release. The drug release within the first twenty-four hours varied from 4 to 16%. The use of a second organic solvent, except ethanol, resulted in a significantly higher drug release during the second half of the dissolution study. The drug release continued more than 60 days.  相似文献   
115.
116.
Significant restriction of growth of Ehrlich's carcinoma was observed following prophylactic treatment on Swiss albino mice with neem leaf preparation (NLP-1 unit) once weekly for four weeks. Toxic effects of this particular dose (1 unit), along with 0.5 unit and 2 units of NLP doses, were evaluated on different murine physiological systems. One hundred percent of mice could tolerate 4 injections of 0.5 and 1 unit NLP doses. Body weight, different organ-body weight ratios and physical behavior of treated mice remained completely unchanged during treatment with different NLP doses. All of these NLP doses were observed to stimulate hematological systems as evidenced by the increase in total count of RBC, WBC and platelets and hemoglobin percentage. As histological changes as well as elevation in serum alkaline phosphatase, SGOT, SGPT were not observed in mice treated with three different doses of NLP, the nonhepatotoxic nature of NLP was proved. The level of serum urea remained unaltered and normal architecture of the cortical and medullary parts of the kidney were also preserved after NLP treatment. Increased antibody production against B16 melanoma antigen was detected in mice immunized with 0.5 unit and 1 unit of NLP. Number of splenic T lymphocytes (CD4+ and CD8+) and NK cells were also observed to be increased in mice injected with 0.5 unit and 1 unit of NLP. However, NLP dose of 2 units could not exhibit such immunostimulatory changes; NLP mediated immunostimulation was correlated well with the growth restriction of murine carcinoma. In other words, tumor growth restriction was observed only when mice were injected with immunostimulatory doses of NLP (0.5 unit and 1 unit).  相似文献   
117.
An updated numerical simulation of unsteady generalized Newtonian blood flow through differently shaped distensible arterial stenoses is developed. A shear-thinning fluid modelling the deformation dependent viscosity of blood is considered for the characterization of generalized Newtonian behaviour of blood. The arterial model is treated as two-dimensional and axisymmetric with an outline of the stenosis obtained from a three-dimensional casting of a mildly stenosed artery. The full Navier-Stokes equations governing blood flow are written in the dimensionless form and the solution is accomplished by finite time-step advancement through their finite difference staggered grid representations. The marker and cell (MAC) method comprising the use of a set of marker particles moving with the fluid is used for the purpose. Results are obtained for three differently shaped stenoses – irregular, smooth and cosine curve representations. The present results do agree well with those of existing investigations in the steady state, but contrary to their conclusions the present findings demonstrate that the excess pressure drop across the cosine and the smooth stenoses is caused by neither their smoothness nor their higher degree of symmetry relative to the irregular stenosis, but is rather an effect of area cover with respect to the irregular stenosis. This effect clearly prevails throughout the entire physiological range of Reynolds numbers. Further the in-depth study in flow patterns reveals the development of flow separation zones in the diverging part of the stenosis towards the arterial wall, and they are influenced by non-Newtonian blood rheology, distensibility of the wall and flow unsteadiness in order to validate the applicability of the present model.  相似文献   
118.
119.
Flow of an electrically conducting fluid characterizing blood through the arteries having irregular shaped multi-stenoses in the environment of a uniform transverse magnetic-field is analysed. The flow is considered to be axisymmetric with an outline of the irregular stenoses obtained from a three-dimensional casting of a mild stenosed artery, so that the physical problem becomes more realistic from the physiological point of view. The marker and cell (MAC) and successive-over-relaxation (SOR) methods are respectively used to solve the governing unsteady magnetohydrodynamic (MHD) equations and pressure-Poisson equation quantitatively and to observe the flow separation. The results obtained show that the flow separates mostly towards the downstream of the multi-stenoses. However, the flow separation region keeps on shrinking with the increasing intensity of the magnetic-field which completely disappears with sufficiently large value of the Hartmann number. The present observations certainly have some clinical implications relating to magnetotherapy which help reducing the complex flow separation zones causing flow disorder leading to the formation and progression of the arterial diseases.  相似文献   
120.
The well-documented acute cardiodynamic changes in canine endotoxemia were significantly altered by pretreatment with either a newly synthesized serotonin receptor antagonist (ketanserin) or with a prostaglandin synthetase inhibitor (indomethacin). Ketanserin, but not indomethacin, significantly attenuated the endotoxin-induced pulmonary hypertension and vasoconstriction but had no effect on the typical systemic hemodynamic changes. In sharp contrast, indomethacin significantly attenuated systemic hypotension and enhanced peripheral vascular resistance. Neither drug influenced the typical acute fall in cardiac output or the capillary permeability edema; neither drug attenuated the metabolic acidosis of endotoxemia. These results imply that, although serotonin and the prostaglandins each participate in a unique manner in the pathophysiology of experimentally induced endotoxic shock, neither autacoid appeared singularly responsible for the hemodynamic and metabolic alterations consistently observed.  相似文献   
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