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71.
72.
In PC Cl3 cells, a continuous, fully differentiated rat thyroid cell line, P2Y(2) purinoceptor activation provoked a transient increase of [Ca(2+)](i), followed by a decreasing sustained phase. The alpha and beta1 protein kinase C (PKC) inhibitor G?6976 decreased the rate of decrement to the basal [Ca(2+)](i) level and increased the peak of Ca(2+) entry of the P2Y(2)-provoked Ca(2+)transients. These effects of G? 6976 were not caused by an increased permeability of the plasma membrane, since the Mn(2+) and Ba(2+) uptake were not changed by G? 6976. Similarly, the Na(+)/Ca(2+) exchanger was not implicated, since the rate of decrement to the basal [Ca(2+)](i) level was equally decreased in physiological and Na(+)-free buffers, in the presence of G? 6976. On the contrary, the activity of the sarcoplasmic-endoplasmic reticulum Ca(2+)ATPase (SERCA) 2b was profoundly affected by G? 6976 since the drug was able to completely inhibit the stimulation of the SERCA 2b activity elicited by P2-purinergic agonists. Finally, the PKC activator phorbol myristate acetate had effects opposite to G? 6976, in that it markedly increased the rate of decrement to the basal [Ca(2+)](i) level after P2Y(2) stimulation and also increased the activity of SERCA 2b. These results suggest that SERCA 2b plays a role in regulating the sustained phase of Ca(2+) transients caused by P2Y(2) stimulation.  相似文献   
73.
Comparative sequence analysis of the PCR products of the M gene and fragments of the pol1a and pol1b genes of canine coronavirus (CCoV) have demonstrated that two separate clusters of CCoV are present in dogs. This note describes a PCR assay to identify atypical CCoV strains with nucleotide substitutions in the M gene. A total of 177 faecal samples from dogs CCoV positive previously with the PCR assay were analysed. Sixty-two of the 177 samples were amplified with the PCR described in the present study and were thus considered atypical CCoVs. The specificity of the PCR typing assay was confirmed by sequence analysis of the PCR products.  相似文献   
74.
We report a case of conjunctival tuberculosis in a trainee microbiologist caused by direct inoculation. The resident strain was analyzed by DNA fingerprinting, and an identical pattern was found in an isolate from sputum handled by the resident. After 6 months of treatment, the patient was cured.  相似文献   
75.
The onset of walking is a fundamental milestone in motor development of humans and other mammals, yet little is known about what factors determine its timing. Hoofed animals start walking within hours after birth, rodents and small carnivores require days or weeks, and nonhuman primates take months and humans approximately a year to achieve this locomotor skill. Here we show that a key to the explanation for these differences is that time to the onset of walking counts from conception and not from birth, indicating that mechanisms underlying motor development constitute a functional continuum from pre- to postnatal life. In a multiple-regression model encompassing 24 species representative of 11 extant orders of placental mammals that habitually walk on the ground, including humans, adult brain mass accounted for 94% of variance in time to walking onset postconception. A dichotomous variable reflecting species differences in functional limb anatomy accounted for another 3.8% of variance. The model predicted the timing of walking onset in humans with high accuracy, showing that this milestone in human motor development occurs no later than expected given the mass of the adult human brain, which in turn reflects the duration of its ontogenetic development. The timing of motor development appears to be highly conserved in mammalian evolution as the ancestors of some of the species in the sample presented here diverged in phylogenesis as long as 100 million years ago. Fundamental patterns of early human life history may therefore have evolved before the evolution of primates.  相似文献   
76.

Background  

Variability in stages of the HIV-1 epidemic and hence HIV-1 prevalence exists in different areas in sub-Saharan Africa. The purpose of this study was to investigate the magnitude of HIV-1 infection and identify HIV-1 risk factors that may help to develop preventive strategies in rural Kilimanjaro, Tanzania.  相似文献   
77.
78.
A detailed casenote review was performed on all 65 patients registered with testicular non-seminomatous germ cell tumours (NSGCT) during 1989 under the Scottish Cancer Registration Scheme. Details of management at presentation and 2 years following diagnosis were recorded and analysed. In a small number of patients an unacceptable delay in diagnosis was noted. Variation was found in the frequency and type of investigations performed on patients placed on surveillance, types of chemotherapy regimens used and numbers of patients entered into trials. Three per cent of patients had a biopsy of the contralateral testis and 27% of patients defaulted from clinic attendance. Considerable variation in the management of testicular NSGCT in Scotland has been identified. The introduction of management guidelines should result in a more consistent approach to the care of these patients. Support, both financial and psychological, may reduce the unacceptable rate of default.  相似文献   
79.
A detailed casenote review was performed on 55 patients registered with testicular non-seminomatous germ cell tumours (NSGCT) between 1983 and 1988 under the Scottish Cancer Registration Scheme and who had died by 1992. Details of all aspects of clinical management relating to their NSGCT and death details were extracted and summarised. An assessment was made on whether the patients'' management had been optimal. An analysis of 5 year survival rates by the five Scottish oncology centres demonstrated significant differences between centres (range 70.4-94.2; chi 2 = 14.46, d.f. = 4, P = 0.006). Some patients in all centres were assessed as having received suboptimal treatment, but two centres performed less well than the other three. There is a suggestion that the number of patients treated suboptimally decreases with increasing number of patients seen, but this does not reach statistical significance.  相似文献   
80.
PURPOSE: Adeno-associated viral (AAV) vectors have been used to express several different proteins in the eye. The purpose of this study was to determine whether AAV-mediated intraocular gene transfer of pigment epithelium-derived factor (PEDF) inhibits the development of choroidal neovascularization (CNV) in a murine model. METHODS: C57BL/6 mice were given intravitreous or subretinal injections of a PEDF expression construct packaged in an AAV vector (AAV-chicken beta-actin promoter-exon 1-intron 1[CBA]-PEDF) or control vector (AAV-CBA-green fluorescent protein[GFP]). After 4 or 6 weeks, the Bruch's membrane was ruptured by laser photocoagulation at three sites in each eye. After 14 days, the area of CNV at each rupture site was measured by image analysis. Intraocular levels of PEDF were measured by enzyme-linked immunosorbent assay. RESULTS: Four to six weeks after intraocular injection of AAV-CBA-PEDF, levels of PEDF in whole-eye homogenates were 6 to 70 ng. The average area of CNV at sites of the Bruch's membrane rupture showed no significant difference in eyes injected with AAV-CBA-PEDF compared with uninjected eyes. In contrast, 4 to 6 weeks after intraocular injection of 1.5 x 10(9) or 2.0 x 10(10) particles of AAV-CBA-PEDF, the area of CNV at the Bruch's membrane rupture sites had significantly decreased compared with CNV area at rupture sites in eyes injected with AAV-CBA-GFP. CONCLUSIONS: These data suggest that intraocular expression of PEDF or other antiangiogenic proteins with AAV vectors may provide a new treatment approach for ocular neovascularization.  相似文献   
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