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排序方式: 共有3513条查询结果,搜索用时 15 毫秒
961.
Subramani Durai Babu Venkataraman Jayanthi Niranjali Devaraj Celso A Reis Halagowder Devaraj 《Molecular cancer》2006,5(1):10-7
Background
Helicobacter pylori (H. pylori) causes gastritis and intestinal metaplasia (IM) that may evolve to gastric carcinoma. The objective of this study was to compare the profile of mucins in the progressive stages of H. pylori infected pre-neoplastic and neoplastic human gastric epithelium. We used a panel of monoclonal antibodies with well-defined specificities of MUC2, MUC5AC and MUC6 to characterize the expression pattern of mucins by immunohistochemistry. 相似文献962.
D L Van Dyke A Wiktor C G Palmer D A Miller M Witt V R Babu M J Worsham J R Roberson L Weiss 《American journal of medical genetics》1992,43(6):996-1005
Since some patients with Ullrich-Turner syndrome (UTS) have mental retardation, we reviewed our experience to look for a high-risk subgroup. Among 190 UTS and gonadal dysgenesis patients with X chromosome abnormalities, 12 had mental retardation. All of the six (100%) with a small ring X were educable (EMI) or trainable mentally impaired (TMI) with more severe delay than expected in UTS. Among the 184 with other X abnormalities, only 6 had similar delays (2 from postnatal catastrophes), for a frequency of 3.3% mental retardation among those without a small ring X; only 2.2% of these had unexplained mental retardation. Polymerase chain reaction studies showed no Y-derived material in the 2 patients who were evaluated, and in situ hybridization confirmed X origin of the ring in the 6 subjects who were evaluated. We describe the phenotype of the 6 individuals with a small ring X, and an additional 2 patients with a small ring X who were identified outside the survey. The subjects with a small ring X comprised a clinically distinct subgroup which had EMI/TMI and shorter stature than expected in UTS. Seizures and a head circumference less than 10th centile were observed in half of the patients with a small ring X, and strabismus, epicanthus, and single palmar creases were present in more than half. A "triangular" face in childhood, pigmentary dysplasia, sacral dimple, and heart defects were also common. Neck webbing appeared to be less frequent than in 45,X. We hypothesize that the high risk of mental retardation in this form of the UTS results from lack of lyonization of the ring X due to loss of the X inactivation center. Excluding those with a small ring X, mental retardation is not significantly increased in patients with UTS. 相似文献
963.
The Smooth Muscle Myosin Seven Amino Acid Heavy Chain Insert's Kinetic Role in the Crossbridge Cycle for Mouse Bladder 总被引:2,自引:1,他引:2
Peter Karagiannis Gopal J. Babu Muthu Periasamy Frank V. Brozovich 《The Journal of physiology》2003,547(2):463-473
The seven amino acid insert in the smooth muscle myosin heavy chain is thought to regulate the kinetics of contraction, contributing to the differences between fast and slow smooth muscle. The effects of this insert on force and stiffness were determined in bladder tissue of a transgenic mouse line expressing the insert SMB at one of three levels: an SMB wild type (+/+), an SMA homozygous type (−/−) and a heterozygous type (+/−). For skinned muscle, an increase in MgADP or inorganic phosphate (Pi ) should shift the distribution of crossbridges in the actomyosin ATPase (AMATPase) to increase the relative population of the crossbridge state prior to ADP release and Pi release, respectively. Exogenous ADP increased force and stiffness in a manner consistent with increasing the Ca2+ concentration in both the +/+ and +/− mouse types. However, the −/− type showed a significantly greater increase in force than in stiffness suggesting that immediately prior to ADP release, the AMATPase either has an additional force producing isomerization state or a slower ADP dissociation rate for the −/− type compared to the +/+ or +/− types. Exogenous Pi led to a significantly greater decrease in stiffness than in force for all three mouse types suggesting that there is a force producing state prior to Pi release. In addition, the increase in Pi showed similar changes in the +/+ and −/− types whereas in the +/− type the decreases in both force and stiffness were greater than the other two mouse types indicating that the insert can affect the cooperativity between myosin heads. In conclusion, the seven amino acid insert modulates the kinetics and/or states of the AMATPase, which could lead to differences in the kinetics of contraction between fast and slow smooth muscle. 相似文献
964.
965.
Clinically important differences in health-related quality of life for patients with asthma: an expert consensus panel report. 总被引:2,自引:0,他引:2
Kathleen W Wyrwich Harold S Nelson William M Tierney Ajit N Babu Kurt Kroenke Fredric D Wolinsky 《Annals of allergy, asthma & immunology》2003,91(2):148-153
BACKGROUND: Standards for change in health-related quality of life (HRQoL) measures used among asthmatic patients have been established by considering only patient preferences to determine important differences and may not reflect an informed clinical evaluation of change. OBJECTIVE: To establish clinically important difference (CID) standards through the consensus of an expert physician panel for the Juniper Asthma Quality of Life Questionnaire (AQLQ) and Medical Outcomes Study Short-Form 36-Item Health Survey (SF-36, version 2) when used to measure HRQoL among asthmatic patients. METHODS: We organized an 8-person panel of physicians familiar with measuring HRQoL among asthmatic patients with the AQLQ and the SF-36. This expert panel participated in 2 rounds of a modified Delphi process before attending an in-person consensus meeting to establish the CID standards for small, moderate, and large changes in the AQLQ and the SF-36. After the consensus meeting, the panel used an iterative improvement process to cooperatively complete their final report. RESULTS: The expert panel's thresholds for detecting CIDs in the domains of the AQLQ were much higher than previously established levels using patient-perceived changes. CIDs for asthma were also ascertained on the scales of the SF-36, version 2, which were markedly greater than previously cited cross-sectional differences between patient groups. CONCLUSIONS: The CID standards established by this expert panel elucidate a potential distinction between patient and physician perspectives of important HRQoL changes. The many stakeholders of HRQoL difference standards should consider this distinction when adopting standards to evaluate patient change. 相似文献
966.
Deary AJ; Seaton JE; Prentice A; Morton NC; Booth AK; Smith SK 《Human reproduction (Oxford, England)》1997,12(7):1494-1496
Our objective was to evaluate the effect of a change in treatment
protocols, suggested following an inspection visit by the regulatory
authority, from single to double inseminations during donor insemination
treatment cycles. We therefore conducted a retrospective audit of pregnancy
rates in the reproductive medicine clinic of a major teaching hospital. All
patients were treated for male factor infertility by donor insemination,
without ovulation induction with gonadotrophins between October 1992 and
December 1995. The main outcome measures were cumulative conception and
live birth rates. During the study period 250 patients underwent treatment
and 650 single insemination and 277 double insemination treatment cycles
were undertaken. The pregnancy rate per cycle was 0.054 and 0.119 for
single and double insemination respectively. After six cycles the
cumulative pregnancy rates were 0.28 and 0.47 and the take-home baby rates
were 0.25 and 0.37 for single and double inseminations respectively. The
change in practice from single to double insemination resulted in a
doubling of the pregnancy rate per treatment cycle. Cumulative pregnancy
rates after two treatment cycles of double insemination were comparable
with those achieved after six cycles of single insemination. These results
have significant implications for both patients and purchasers.
相似文献
967.
The clinical utility of carotid duplex scanning 总被引:1,自引:0,他引:1
We retrospectively compared the results of duplex scanning (DS) with contrast angiography (CAN) in the evaluation of 119 patients whose 238 carotid arteries were evaluated by both methods within a four-week period. The results of all patients were then categorized by two different definitions of severity of stenosis. Category A classified 1-29% stenosis as mild, 30-69% stenosis as moderate, and 70-99% diameter reduction as severe stenosis. Category B defined mild stenosis as 1-19% lumen diameter reduction, moderate as 20-49% stenosis, and severe as 50-99% stenosis. The findings by each classification were compared in 60 patients with hemispheric symptoms and in 59 patients with nonspecific symptoms. CAN was our "gold standard", and exhibited greater sensitivity, specificity, accuracy, and predictive values than DS. Carotid arteries with 70% stenosis were identified by DS with greater specificity, accuracy, and predictive values than were arteries with 50% stenoses. Only the sensitivity was comparable in categorizations A and B (80% and 83%). All parameters of measurement were superior in patients with hemispheric symptoms. DS alone cannot substitute for CAN in selecting patients for carotid endarterectomy because its error rate exceeded acceptable rates of complications for carotid artery surgery. The false positive rate of DS was 4%. DS failed to diagnose 7 of 19 carotid artery occlusions, 9 of 11 ulcerated plaques, 7 of 119 instances of aortic arch disease, and 13 cases of severe intracranial artery stenosis. 相似文献
968.
Submicroscopic deletions in the Y chromosome of infertile men 总被引:11,自引:18,他引:11
Recent investigations have suggested a high prevalence of Y chromosome
submicroscopic deletions in men with severely impaired spermatogenesis. We
evaluated the frequency of Y chromosome deletions in 160 infertile men
using a series of 36 sequence-tagged-sites, emphasizing intervals 5 and 6
of the long arm of the Y chromosome. Peripheral leukocyte DNA was extracted
and amplified with two parallel techniques to minimize potential
overestimation of the frequency of deletions. The presence of deletions was
evaluated relative to patient's sperm concentration, testis volume, and
hormonal parameters. Men with sperm concentration <5 x 10(6)/ml had a 7%
prevalence of submicroscopic Y chromosome deletions. Deletions were
detected in 7% of azoospermic men, 10% of men with <1 x 10(6)
spermatozoa/ml, and 8% of men with >1 x 10(6) but <5 x 10(6)
spermatozoa/ml. Other clinical parameters did not identify men with Y
chromosome deletions prior to polymerase chain reaction (PCR)- based
testing for the presence of sequence-tagged-sites. Two distinct regions of
Y chromosome deletions were detected, approximately 3.6 Mb and 1.4 Mb in
length respectively. These deleted regions are present in AZFb and AZFc
respectively. No deletions were detected in AZFa. The loss of these two
distinct areas is supported by the finding of highly repetitive sequences
along the Y chromosome, predisposing to deletion of specific intervals on
the Y chromosome during meiosis. Men with severe male infertility are at
high risk for Y chromosome deletions. Testing of men for these genetic
abnormalities is indicated prior to treatment with assisted reproduction.
相似文献
969.
Genomic screening for beta-sarcoglycan gene mutations: missense mutations may cause severe limb-girdle muscular dystrophy type 2E (LGMD 2E) 总被引:7,自引:3,他引:7
Bonnemann CG; Passos-Bueno MR; McNally EM; Vainzof M; de Sa Moreira E; Marie SK; Pavanello RC; Noguchi S; Ozawa E; Zatz M; Kunkel LM 《Human molecular genetics》1996,5(12):1953-1961
Autosomal recessive limb-girdle muscular dystrophies (LGMDs) are
genetically heterogeneous. A subgroup of these disorders is caused by
mutations in the dystrophin-associated sarcoglycan complex. Truncating
mutations in the 43 kDa beta-sarcoglycan gene (LGMD 2E) were originally
identified in a sporadic case of Duchenne-like muscular dystrophy, and a
common missense mutation (T151R) was identified independently in Indiana
Amish pedigrees with a milder form of LGMD. To facilitate mutational
analysis of larger numbers of patients directly from genomic DNA, as
opposed to reverse transcribed RNA from muscle biopsies, we have determined
the genomic structure of the beta-sarcoglycan gene. The open reading frame
of the beta-sarcoglycan coding region extends over six exons. Primers were
designed for PCR amplification of single exons from genomic DNA and
subsequent single strand conformation polymorphism (SSCP) analysis. We
screened 15 patients from the Brazilian LGMD patient population, 13 of whom
followed a severe course. Most of the patients had been assessed previously
for deficiency of alpha- sarcoglycan immunofluorescence on muscle biopsy
sections as a marker for disease of the sarcoglycan complex. Novel
mutations in two familial and two sporadic cases of severe childhood-onset
LGMD were identified. Only one of these patients carried a truncating
mutation (homozygous 2 bp deletion, FS164TER), while the other three
carried missense mutations (homozygous R91P, homozygous M100K, heterozygous
recessive L108R; only one allele could be identified in this family). All
three missense mutations occurred in exon 3, coding for the immediate
extracellular domain. Complete absence for all three of the known
sarcoglycans was noted by immunohistochemistry on muscle biopsy sections of
the patients.
相似文献
970.
K Babu M Sonnenberg S Kathpalia P Ortega A L Swiatlo F E Kocka 《Journal of clinical microbiology》1990,28(2):361-362
Salmonella arizonae and other Salmonella serovars were isolated from four different rattlesnake preparations which were used for self-treatment of various diseases. A case of disseminated S. arizonae infection is reported in a patient who had acquired immunodeficiency syndrome and ingested dried rattlesnake. 相似文献