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121.
Ninety two Friesian cows were used to determine physical properties of cervical mucus collected during normal estrus and estrus induced. Estrus was induced using either progesterone (P4) releasing intravaginal devices (PRID) and/or prostaglandin F2alpha (PGF2alpha). The animals were assigned to 4 groups (no treatment, a PRID for 12 days plus an injection of 1000 IU PMSG at the removal of the PRID, a double injection of 3 mL PGF2alpha 11 days apart, and a PRID for 7 days plus an injection of PGF2alpha 24 h before the removal of PRID). A number of cows with normal estrus exhibited three consecutive estrus cycles after calving. Cows that had not shown estrus for three months after calving had their reproductive system palpated twice at 10-day intervals, to determine their ovarian activity. Then PRID and/or PGF2alpha was administered to cows that were found to have a palpable corpus luteum in one of two palpations (cycling cows). The cows of the three induced estrous groups were artificially inseminated (AI) twice, while those with normal estrus received only a single AI. Cervical mucus samples were collected from all cows 5 to 30 min before the first AI. Additionally, samples of cervical mucus were collected from 20 cows at their first estrus after the induced estrus. The results are summarized as follows: 1) The physical properties of cervical mucus were similar in the first three normal consecutive estrus cycles after calving. 2) The physical properties of cervical mucus in normal estrus after calving were similar to those in the first estrus after an induced estrus. 3) The pH values for normal estrus were similar to those for induced estrus. 4) Viscosity of cervical mucus in the normal estrous group was significantly lower than that in the induced estrus. Furthermore, significant differences were noticed among the three induced estrous groups. 5) Spinnbarkeit, crystallization and receptivity of cervical mucus (penetration test) were significantly higher in the normal estrous group than in the induced estrous groups, while no difference was detected among induced estrus groups. 6) Pregnancy rates in the normal estrus group were the same as in the induced estrus groups. 7) The percentages of cows in the induced estrous groups that produced cervical mucus with similar viscosity, spinnbarkeit and receptivity (penetration test) characteristics as the normal estrus group, was very low.  相似文献   
122.
In this study, a probabilistic degree‐day phenology model has been developed for the codling moth, Cydia pomonella, and calibrated using data from laboratory growth studies. The model is further used to predict the succession and overlapping of certain biological events of C. pomonella in probabilistic‐physiological time scale in northern Greece fruit orchards. The model satisfactorily predicts the stage‐specific pest population dynamics, including egg laying and hatching, the occurrence of larvae and pupae stages and the emergence of adults. According to the model projections for the adult flights, there is a very high probability, p = 0.999, of observing adults of the first flight generation until 333 degree‐days (DD), but a very low probability of finding adults of the second flight generation. Moreover, at 575 DD, the probability of finding an individual to lay eggs is p = 0.15. However, there is nearly the same probability of egg hatch, p = 0.36, and larval completion p = 0.313, while at the same time, the probability of pupal completion is very low, p = 0.001. The above model predictions were validated using field data for the adult stage emergence as well as for the percentage of larval damage providing satisfactory results considering that larval emergence prediction was close to actual fruit damage observed in field. This information is very important considering that IPM programs rely on the use of biorational compounds, such as IGRs and bio‐toxins which are stage selective and often have a shorter residual activity than the preceding broad‐spectrum insecticides.  相似文献   
123.
Aim We focus on the biogeographical role of the Balkan Peninsula as a glacial refugium and source of northward post‐glacial dispersal for many European taxa. Specifically, we analysed the genetic structure and variation of wild boar (Sus scrofa) samples primarily from Greece, a region that has repeatedly served as a glacial refugium within the Balkan Peninsula. Location Continental Greece, the Aegean island of Samos and Bulgaria. Methods We analysed wild boar samples from 18 localities. Samples from common domestic breeds were also examined to take into account interactions between wild and domesticated animals. Phylogenetic analyses were carried out on a 637‐bp fragment of the mitochondrial DNA control region in 200 wild boar and 27 domestic pigs. The sequences were also compared with 791 Eurasian wild boar and domestic pig D‐loop sequences obtained from GenBank. Results Ninety‐four haplotypes were identified in the European wild boar data set, of which 68 were found in the Balkan samples and assigned to two previously described clades: the E1 European and Near Eastern clades. All of the continental samples clustered in the E1 clade and the samples from Samos fell into the Near Eastern clade, consistent with the island’s proximity to Asia Minor. Intriguingly, 62 novel haplotypes were identified and are found exclusively in the Balkans. Only six haplotypes were shared between wild boar and domestic pigs. Main conclusions Our data reveal numerous novel and geographically restricted haplotypes in wild boar populations, suggesting the presence of separate refugia in the Balkans. Our analyses support the hypothesis of a post‐glacial wild boar expansion consistent with the leading edge model, north and west from modern day Greece, and suggest little maternal introgression of Near Eastern and domestic haplotypes into wild Balkan populations.  相似文献   
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126.

Background

While the high burden of multidrug-resistant tuberculosis (MDR-TB) itself is a matter of great concern, the emergence and rise of advanced forms of drug-resistance such as extensively drug-resistant TB (XDR-TB) and extremely drug-resistant TB (XXDR-TB) is more troubling. The aim of this study was to investigate the trends over time of patterns of drug resistance in a sample of MDR-TB patients in greater metropolitan Mumbai, India.

Methods

This was a retrospective, observational study of drug susceptibility testing (DST) results among MDR-TB patients from eight health care facilities in greater Mumbai between 2005 and 2013. We classified resistance patterns into four categories: MDR-TB, pre-XDR-TB, XDR-TB and XXDR-TB.

Results

A total of 340 MDR-TB patients were included in the study. Pre-XDR-TB was the most common form of drug-resistant TB observed overall in this Mumbai population at 56.8% compared to 29.4% for MDR-TB. The proportion of patients with MDR-TB was 39.4% in the period 2005–2007 and 27.8% in 2011–2013, while the proportion of those with XDR-TB and XXDR-TB was changed from 6.1% and 0% respectively to 10.6% and 5.6% during the same time period. During the same periods, the proportions of patients with ofloxacin, moxifloxacin and ethionamide resistance significantly increased from 57.6% to 75.3%, from 60.0% to 69.5% and from 24.2% to 52.5% respectively (p<0.05).

Discussion

The observed trends in TB drug-resistance patterns in Mumbai highlight the need for individualized drug regimens, designed on the basis of DST results involving first- and second-line anti-TB drugs and treatment history of the patient. A drug-resistant TB case-finding strategy based on molecular techniques that identify only rifampicin resistance will lead to initiation of suboptimal treatment regimens for a significant number of patients, which may in turn contribute to amplification of resistance and transmission of strains with increasingly advanced resistance within the community.  相似文献   
127.
We provide a review and synthesis of key findings in phylogeographic research on terrestrial animals in the Aegean archipelago (Greece) and surrounding regions (Greek mainland, southern Balkans and Asia Minor). A critical review of more than 100 phylogeographic articles on 76 animal genera (30 invertebrates and 46 vertebrates) that have been published so far for the region leads to the recognition of three types of distribution patterns: old ‘colonizers’ diversified in the Aegean before the formation of the mid‐Aegean Trench (MAT – i.e. before 9 Mya), post‐MAT colonizers that arrived to the Aegean in late Miocene and Pliocene and new colonizers that inhabited the region in the Pleistocene or even the Holocene. Several problems, mainly regarding the use of calibration points and/or molecular clock rates for clade chronology, have been identified in many analyses. Despite the large amount of phylogeographic work concerning the Aegean and surrounding regions, many groups remain unstudied (especially invertebrates, micro‐organisms, fungi and plants), and many issues still remain unresolved. The relative roles of extinction, speciation, dispersal and vicariance, as well as the effects of adaptive and non‐adaptive components of diversification, need further analyses with modern tools that can provide deeper insights. A more detailed reconstruction of the palaeogeography of the region is also of prime importance. The critical views presented herein may prove useful also for the evaluation of similar work in other regions.  相似文献   
128.

Background

Subjective visual assessment of cervical cytology is flawed, and this can manifest itself by inter- and intra-observer variability resulting ultimately in the degree of discordance in the grading categorisation of samples in screening vs. representative histology. Biospectroscopy methods have been suggested as sensor-based tools that can deliver objective assessments of cytology. However, studies to date have been apparently flawed by a corresponding lack of diagnostic efficiency when samples have previously been classed using cytology screening. This raises the question as to whether categorisation of cervical cytology based on imperfect conventional screening reduces the diagnostic accuracy of biospectroscopy approaches; are these latter methods more accurate and diagnose underlying disease? The purpose of this study was to compare the objective accuracy of infrared (IR) spectroscopy of cervical cytology samples using conventional cytology vs. histology-based categorisation.

Methods

Within a typical clinical setting, a total of n = 322 liquid-based cytology samples were collected immediately before biopsy. Of these, it was possible to acquire subsequent histology for n = 154. Cytology samples were categorised according to conventional screening methods and subsequently interrogated employing attenuated total reflection Fourier-transform IR (ATR-FTIR) spectroscopy. IR spectra were pre-processed and analysed using linear discriminant analysis. Dunn’s test was applied to identify the differences in spectra. Within the diagnostic categories, histology allowed us to determine the comparative efficiency of conventional screening vs. biospectroscopy to correctly identify either true atypia or underlying disease.

Results

Conventional cytology-based screening results in poor sensitivity and specificity. IR spectra derived from cervical cytology do not appear to discriminate in a diagnostic fashion when categories were based on conventional screening. Scores plots of IR spectra exhibit marked crossover of spectral points between different cytological categories. Although, significant differences between spectral bands in different categories are noted, crossover samples point to the potential for poor specificity and hampers the development of biospectroscopy as a diagnostic tool. However, when histology-based categories are used to conduct analyses, the scores plot of IR spectra exhibit markedly better segregation.

Conclusions

Histology demonstrates that ATR-FTIR spectroscopy of liquid-based cytology identifies the presence of underlying atypia or disease missed in conventional cytology screening. This study points to an urgent need for a future biospectroscopy study where categories are based on such histology. It will allow for the validation of this approach as a screening tool.  相似文献   
129.
The purpose of this study was to examine the moment-arm and cross-sectional area (CSA) of the patellar tendon (PT) and the hamstrings after anterior cruciate ligament (ACL) reconstruction. The right knee of five males who underwent ACL reconstruction with a PT graft and five age-matched controls was scanned using magnetic resonance image scans. Based on three-dimensional (3D) solids of the PT, CSAs and moment-arms of semitendinous (ST), biceps femoris (BF) long head and semimembranosus (SM) were estimated. Analysis of variance indicated no significant group differences in muscle moment-arms (p>0.05). 3D moment-arms of PT, ST and BF were significantly lower than the corresponding 2D values (p < 0.05). The ACL group displayed a significantly higher maximum BF CSA, a lower ST CSA (p < 0.05) but similar PT and SM CSAs compared with controls. It is concluded that any alterations in PT properties 1 year after harvesting do not affect knee muscle moment-arms compared with age-matched controls. Moment-arm estimation differed between 3D and 2D data, although it did not affect comparisons between ACL reconstruction group and controls. Design of rehabilitation programmes should take into consideration a potential alteration in hamstring morphology following surgery with a PT graft.  相似文献   
130.
Members of the human epidermal growth factor receptor (HER) family play a significant role in bladder cancer progression and may underlie the development of chemotherapy resistance. Dacomitinib is an irreversible tyrosine kinase inhibitor with structural specificity for the catalytic domains of epidermal growth factor receptor (EGFR), HER2 and HER4 that has exhibited vigorous efficacy against other solid tumors. We evaluated the antitumor activity of dacomitinib in human bladder cancer cell lines expressing varying levels of HER family receptors. These cell lines also were established as bladder cancer xenografts in nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice to assess dacomitinib activity in vivo. Significant cytotoxic and cytostatic effects were noted in cells expressing elevated levels of the dacomitinib target receptors with apoptosis and cell cycle arrest being the predominant mechanisms of antitumor activity. Cells expressing lower levels of HER receptors were much less sensitive to dacomitinib. Interestingly, dacomitinib was more active than either trastuzumab or cetuximab in vitro, and exhibited increased growth inhibition of bladder tumor xenografts compared with lapatinib. Pharmacodynamic effects of dacomitinib included decreased E-cadherin (E-cad) expression, reduction of EGFR and extracellular signal-regulated kinase (ERK) phosphorylation and reduced mitotic count. Dacomitinib also inhibited tumor growth in a chemotherapy-resistant xenograft and, when combined with chemotherapy in a sensitive xenograft, exhibited superior antitumor effects compared with individual treatments. Evaluation in xenograft-bearing mice revealed that this combination was broadly feasible and well tolerated. In conclusion, dacomitinib exhibited pronounced activity both as a single agent and when combined with chemotherapy in human bladder cancer models. Further investigation of dacomitinib in the preclinical and clinical trial settings is being pursued.  相似文献   
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