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排序方式: 共有4319条查询结果,搜索用时 15 毫秒
11.
S Kumar A Kumar P K Goyal G C Jagetia P Uma Devi 《Strahlentherapie und Onkologie》1992,168(10):610-612
The alterations in the oesophageal epithelium were studied in mice after a single whole-body exposure to 7.5 Gy of Co-60 gamma rays in presence or absence of 2-mercaptopropionyl glycine. The epithelium showed an increase in the thickness which reached a maximum on the third day and then decreased gradually up to seventh day after irradiation in the non-drug treated group. In the 2-mercaptopropionyl glycine treated animals the epithelial thickness remained in the normal range except on the day 7 when it was significantly lower than normal. The total cell population registered a steady decline from one to seven days post-irradiation in both groups, but the number of cells was more in the 2-mercaptopropionyl glycine treated group. The number of pycnotic nuclei showed an inverse relationship to the total cell population, it increased continuously up to seven days in both the protected and non-protected groups. However, pycnotic nuclei were significantly lower in the protected group on days 3, 5 and 7 in non-protected group. 相似文献
12.
Jyoti P. Dabholkar Mukesh More Kumar Avanindra Arpit Sharma 《Indian journal of otolaryngology and head and neck surgery》2007,59(4):357-359
Primary amyloidosis of larynx is an uncommon phenomenon, the precise etiopathogenesis of which is not yet clear. It can present with slowly increasing hoarseness or difficulty in breathing. It presents more commonly as infiltrative lesion, exophytic presentation is a rare occurrence. 相似文献
13.
14.
K. S. Kohli D. V. Rai P. Kumar V. K. Jindal Dr. N. Goyal 《Medical & biological engineering & computing》1997,35(4):348-353
The complex electrical impedance of a goat eye lens is studied in the frequency range 10mHz−10Hz at room temperature, using
a computer-controlled AC impedance system. AC impedance software (model 368, version 2.2) is employed to determine the total
impedance and capacitance of the eye lens at various frequencies. A Cole-Cole plot of the eye lens material is drawn between
the real component of impedance Z′ and the imaginary component Z″ for each excitation frequency that shows a perfect arc of
a semicircle, with its centre lying below the abscissa at an angle of 35°. The half-angle ϕ between R0 and R∞ is found to be 55°, which mathematically demonstrates the selective permeability of the eye lens. Using graphical analysis
of the Cole-Cole plot, characteristic frequency fc and distribution factor α are observed to be 1Hz and 0.77, respectively. At characteristic frequency, capacitance and total
impedance are found to be 1.14μF and 9.08kΩ. The effect of electrode polarisation on capacitance is corrected, based on Fricke's
power function. The observed electrical parameters are then used to explain the multiple current path through various tissue
compartments. Further, an attempt is made to explain the results on the basis of a possible dipolar model. 相似文献
15.
K. S. Kohli Dr. D. V. Rai V. K. Jindal N. Goyal 《Medical & biological engineering & computing》1998,36(5):604-607
A computer assisted AC impedance system is used to measure the DC voltage—current (V-I) characteristics and AC impedance of
a goat eye lens using a two-probe Ag−AgCl electrode system. The measurement of the V-I characteristics shows that when a DC
voltage from 0mV to 30mV is applied, the resultant current decreases from an initial value of 0.58μA to 0.006μA. However,
when the voltage is increases beyond 30mV, the current increases and reaches a value of 0.9μA at 100mV. The data on the frequency
response (0.01–10 Hz) of the impedance of lens tissue show an inverse relationship with frequency. The effect of various DC
voltages, namely 0, 30, 50, 100 and 200 mV, on the impedance of the eye lens is also investigated over a frequency range of
0.01–10 Hz. The measurement results for both V-I characteristics and AC impedance further suggest the presence of a 30 mV
voltage compartment in the goat eye lens. 相似文献
16.
Summary A DNA hybridization technique, using the polyrepetitiveEcoRI L-fragment of bovid herpesvirus (BHV-4) as a probe, was developed to determine virus distribution in the tissues of BHV-4-infected pregnant rabbits. The cloned fragment did not react with the DNA of rabbits or of other herpesviruses, e.g., infectious bovine rhinotracheitis, bovine herpes virus mammillitis, and pseudorabies viruses. The detection limit was 10–13g of DNA or approximately 600 genome equivalents of viral DNA, which indicates a level of sensitivity of one viral genome per 500 cells in our assay. Using conventional cell culture techniques, the virus was isolated from only one of fifteen infected rabbits and a few aborted fetuses. However, when organ culture or dot blot hybridization was used, BHV-4 was detected in all rabbits and their fetuses. Viral DNA was detected by DNA hybridization in spleen, ovary, uterus, lung, liver, salivary gland, lymph node, and placentome of adult rabbits and in a composite of fetal tissues. When polymerase chain reaction (PCR) was used, the virus was detected in several organs (including the nervous tissues) that were found negative by other techniques. These results indicate that blot hybridization and PCR are more sensitive than conventional techniques for studying the pathogenesis of BHV-4 in animals. The data obtained by these methods suggest that BHV-4 may be maintained in infected rabbits in a latent state in a variety of tissues including the nervous system. 相似文献
17.
Kudrimoti J Bindu R Hayatnagarkar N Bhople K 《Indian journal of pathology & microbiology》2004,47(2):257-258
Primary malignant melanoma of cervix is a rare entity. A case of primary malignant melanoma of cervix presented with vaginal discharge and black colored growth over cervix. Histology showed malignant pleomorphic cells with melanin pigment in the cytoplasm. 相似文献
18.
Association of TNF-beta polymorphism with disease severity among patients infected with hepatitis C virus 总被引:2,自引:0,他引:2
Goyal A Kazim SN Sakhuja P Malhotra V Arora N Sarin SK 《Journal of medical virology》2004,72(1):60-65
The pathogenesis of chronic hepatitis C virus (HCV) infection remains unclear. Tumour necrosis factor alpha (TNF-alpha) is alleged to contribute in the pathogenesis of chronic HCV infection. Single nucleotide polymorphism in TNF-alpha and -beta genes could influence the outcome of HCV infection. The aim was to study single nucleotide polymorphism in TNF-alpha promoter region and Nco I polymorphisms in the TNF-beta gene in patients with chronic hepatitis C. Fifty-two patients with histologically proven chronic hepatitis, who had raised ALT levels (>1.5 x ULN) and were HCV RNA positive, were studied. Genotyping of -308 promoter variant of TNF-alpha was performed by PCR with primers that incorporated an Nco I restriction site. For PCR typing of the TNF-beta Nco I restriction fragment length polymorphism, sequence specific primers were used. Polymorphism in the TNF-alpha G/G, G/A and A/A allele was not different between HCV patients and healthy controls. TNF-beta A/A allele was significantly more common (P = 0.02) in patients (28.8%) as compared to controls (12.8%), whereas no significant difference was observed for TNF-beta G/A and G/G alleles [corrected]. Nco I TNF-beta A/A was strongly associated with -308 TNF-alpha G/G (RR of HCV persistence = 4.9), indicating possible linkage between TNF-beta A/A and TNF-alpha G/G allele. Patients with severe hepatic fibrosis more frequently had the TNF-beta A/A allele as compared to patients with mild disease (P = 0.04). Immunogenetic factors, such as single nucleotide polymorphisms in TNF-beta (A/A allele), may affect the natural course of HCV infection, in particular, the disease progression. Larger studies including cytokine expression profiles are needed to fully understand the contribution of the polymorphisms described in the pathogenesis of chronic hepatitis C. 相似文献
19.
Jyoti V. Chauthaiwale Takayuki Sakai Samuel E. Taylor Indu S. Ambudkar 《Pflügers Archiv : European journal of physiology》1996,432(1):105-111
The molecular mechanism(s) involved in mediating Ca2+ entry into rat parotid acinar and other non-excitable cells is not known. In this study we have examined the kinetics of
Ca2+ entry in fura-2-loaded parotid acinar cells, which were treated with thapsigargin to deplete internal Ca2+ pools (Ca2+-pool-depleted cells). The rate of Ca2+ entry was determined by measuring the initial increase in free cytosolic [Ca2+] ([Ca2+]i) in Ca2+-pool-depleted, and control (untreated), cells upon addition of various [Ca2+] to the medium. In untreated cells, a low-affinity component was detected with K
Ca = 3.4 ± 0.7 mM (where K
Ca denotes affinity for Ca2+) and V
max = 9.8 ± 0.4 nM [Ca2+]i /s. In thapsigargin-treated cells, two Ca2+ influx components were detected with K
Ca values of 152 ± 79 μM (V
max = 5.1 ± 1.9 nM [Ca2+]i/s) and 2.4 ± 0.9 mM (V
max = 37.6 ± 13.6 nM [Ca2+]i/s), respectively. We have also examined the effect of Ca2+ and depolarization on these two putative Ca2+ influx components. When cells were treated with thapsigargin in a Ca2+-free medium, Ca2+ influx was higher than into cells treated in a Ca2+-containing medium and, while there was a 46% increase in the V
max of the low-affinity component (no change in K
Ca), the high-affinity component was not clearly detected. In depolarized Ca2+-pool-depleted cells (with 50 mM KCl in the medium) the high-affinity component was considerably decreased while there was
an apparent increase in the K
Ca of the low-affinity component, without any change in the V
max. These results demonstrate that Ca2+ influx into parotid acinar cells (1) is increased (four- to five-fold) upon internal Ca2+ pool depletion, and (2) is mediated via at least two components, with low and high affinities for Ca2+.
Received: 30 October 1995/Received after revisionand accepted: 13 December 1995 相似文献
20.