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排序方式: 共有3219条查询结果,搜索用时 31 毫秒
21.
In vitro assays demonstrate photoreactivating enzyme activity in extracts of Candida pseudotropicalis but not in extracts of Candida albicans, Candida stellatoidea, or Candida tropicalis. 相似文献
22.
Yuichi Takeoka Shao-Yuan Chen Richard L. Boyd Koichi Tsuneyama Nobuhisa Taguchi Shinji Morita Hisashi Yago Seishi Suehiro Aftab A. Ansari Leonard D. Shultz M. Eric Gershwin 《Clinical & developmental immunology》1997,5(2):79-89
It is widely accepted that the thymic microenvironment regulates normal thymopoiesis
through a highly coordinated and complex series of cellular and cytokine interactions. A direct
corollary of this is that abnormalities within the microenvironment could be of etiologic
significance in T-cell-based diseases. Our laboratory has developed a large panel of
monoclonal antibodies (mAbs) that react specifically with epithelial or nonepithelial
markers in the thymus. We have taken advantage of these reagents to characterize the
thymic microenvironment of several genetic strains of mice, including BALB/cJ,
C57BL/6J, NZB/BlnJ, SM/J, NOD/Ltz, NOD/Ltz-scid/sz, C57BL/6J-Hcph
me/Hcph me, and
ALY/NscJcl-aly/aly mice, and littermate control animals. We report herein that control
mice, including strains of several backgrounds, have a very consistent phenotypic profile
with this panel of monoclonal antibodies, including reactivity with thymic epithelial cells
in the cortex, the medulla and the corticomedullary junction, and the extracellular matrix.
In contrast, the disease-prone strains studied have unique, abnormal staining of thymic cortex
and medulla at both the structural and cellular levels. These phenotypic data suggest
that abnormalities in interactions between developing thymocytes and stromal cells characterize
disease-prone mice. 相似文献
23.
24.
The nucleotide sequence and genome organization of a new member of Caliciviridae was determined. Cell culture inoculated with fecal matter from walrus was used to recover fragments of a new virus by Suppression Subtractive Hybridization (SSH). The isolate was identified as a member of the Vesivirus genus of Caliciviridae and designated the name Walrus Calicivirus (WCV). Sets of PCR primers spanning the entire putative genome were designed using known sequences of other vesiviruses. The assembled genome was 8289 nucleotides (nt) long and shared no more than 87% identity with sequences of the other members of the genus Vesivirus. The largest open reading frame (ORF1) between positions 4-5646 encoded a polyprotein. ORF2, found at position 5652-7778, encoded a putative capsid protein. ORF3 overlapped ORF2 and encoded a small basic protein. Comparative analysis of multiple caliciviral capsid proteins was performed to propose a uniform capsid structural organization for this viral family. 相似文献
25.
26.
27.
Peter J. Lang Michael J. Kozak Gregory A. Miller Daniel N. Levin Alvin McLean Jr. 《Psychophysiology》1980,17(2):179-192
28.
Pincivero DM Aldworth C Dickerson T Petry C Shultz T 《European journal of applied physiology》2000,81(6):504-509
It has been hypothesized that the ability of the neuromuscular system to co-contract muscles for joint stabilization may
be impaired during the development of fatigue. The purpose of this study was to examine muscle activation of the quadriceps
and hamstring muscles during a prolonged closed kinetic chain exercise, the forward lunge. Eight males and two females [mean
(SD) age 26.0 (2.3) years, height 177.2 (13.6) cm, body mass 82.8 (17.1) kg] with no prior knee pathology volunteered for
this study. Subjects performed repeated forward lunges onto their dominant leg at the cadence of one full lunge cycle every
2 s, until the point of volitional failure. Digital switches were positioned to record foot-strike and knee-strike of the
lunge leg at the midpoint of the lunge, as well as heel-strike upon return to stance. During the lunge performance, surface
electromyographic (EMG) signals of the vastus lateralis (VL), vastus medialis (VM), biceps femoris (BF), and semitendinosus
(ST) muscles of the supporting leg were measured. Heart rate was also monitored every 30 s during the performance. All EMG
data were full-wave rectified, partitioned into up and down phases, and integrated over the entire exercise period. The results
demonstrated a significant increase in activation of the VL, VM, and BF during performance of the forward lunge to volitional
failure (P < 0.05). No significant increase was shown for the ST. Heart rate increased significantly over the course of the lunge. These
findings suggest that activation of the VL, VM, and BF muscles occurs as a unit during performance of the forward lunge during
both concentric and eccentric lunge phases.
Accepted: 25 October 1999 相似文献
29.
Tapsall JW Shultz T Limnios E Munro R Mercer J Porritt R Griffith J Hogg G Lum G Lawrence A Hansman D Collignon P Southwell P Ott K Gardam M Richardson CJ Bates J Murphy D Smith H;National Neisseria Network of Australia 《Pathology》2001,33(3):359-361
A total of 1434 strains of Neisseria meningitidis isolated from cases of invasive meningococcal disease (IMD) in Australia between 1994 and 1999 were examined by standard methods for susceptibility to antibiotics used for treatment and prophylaxis. The proportion of isolates fully susceptible to penicillin decreased from 45% in 1994 to 26% in 1999 (P<0.001). All the other isolates were less sensitive to penicillin except for two meningococci with a penicillin MIC of 1 mg/l. The geometric mean penicillin MIC increased from 0.045 to 0.065 mg/l from 1994 to 1999. There was no significant difference in the geometric mean penicillin MICs of serogroup B and serogroup C meningococci. Penicillin susceptibility was significantly associated with a poorer outcome. Isolates from survivors of IMD had a higher geometric mean penicillin MIC (0.06 mg/l) than those from fatal cases (0.048 mg/l) (P< 0.001). This suggests that factors other than the decrease in susceptibility to penicillin observed were more relevant to outcome in IMD. All isolates were fully susceptible to ceftriaxone. Rifampicin resistance was infrequent (eight isolates in 6 years) and sporadic. A single isolate had decreased quinolone susceptibility. Despite the significant shift in susceptibility to penicillin recorded, this group of antibiotics remains a suitable treatment for IMD in Australia. 相似文献
30.
Moore GD Lear SC Wills-Frank LA Martin AW Snyder JW Helm CW 《Diagnostic cytopathology》2005,32(2):82-87
Our objective was to correlate p16, p21cip1, p27kip1, and cyclin E protein expression with the degree of dysplasia on ThinPrep Papanicolaou (Pap) smears using a modified immunoperoxidase staining. Smears read as normal, atypical squamous cells of undetermined significance (ASC-US), low-grade squamous intraepithelial lesion (LSIL), or high-grade SIL (HSIL) were identified and tested for high-risk human papillomavirus (HR-HPV). Additional smears were processed for immunoperoxidase for p16, p21cip1, p27kip1, and cyclin E. Thirty-four smears were satisfactory for study. The p16 was positive in all nine HSIL, in four of nine LSIL, and in one of seven ASC-US. The p27kip1 was positive in all nine HSIL, in eight of nine LSIL, and in one of seven ASC-US. The p21cip1 was positive in all nine HSIL, in one of nine LSIL, and in one of seven ASC-US. Cyclin E was positive in seven of nine HSIL and in one of nine LSIL and in none of the ASC-US smears. Normal smears were negative for all the antigens. There was poor correlation of protein expression and HR-HPV infection. We concluded that p16, p21cip1, p27kip1, and cyclin E can be demonstrated on Pap smears and they are expressed differentially in dysplastic cells, with highest expression in HSIL. The p21cip1 and cyclin E showed the greatest correlation with HSIL. 相似文献