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1.
Although B-cell chronic lymphocytic leukemia (B-CLL) is the most common form of leukemia in Western countries, little is known about its underlying molecular abnormalities and their prognostic significance, particularly for use in early therapeutic interventions in young patients. As TP53 tumor suppressor gene abnormalities and 11q23 deletions are reported to be prognostically adverse in hematologic malignancies, we used interphase fluorescence in situ hybridization to analyze their incidence and prognostic significance in young B-CLL patients. Bone marrow samples from 40 untreated B-CLL patients at diagnosis were studied using five yeast artificial chromosome clones from the 11q23.1 approximately q23.3 chromosomal region and a probe specific for the 17p13.1 locus. Twenty-three patients (58%) carried 11q deletions. Interestingly, 16 of 17 patients (94%) who showed early disease progression exhibited this chromosomal abnormality, suggesting that 11q deletions may help to identify more aggressive disease in early stage patients. In contrast, monoallelic TP53 deletions were found in all of the patients. The TP53 and 11q deletions were only present in a proportion of the clonal B-cells, which suggests that they are secondary events in B-CLL.  相似文献   
2.
Previous work has shown that the metastatic potential of RSV-transformed fibroblasts is correlated with the ability to form colonies in 0.6% ("hard") agar. Metastatic subclones were selected by this property from the non-metastasizing fibrosarcoma B77-313 line. A marker chromosome was found at high frequency (90% of cells) in all the subclones studied. This marker was detectable in only 0.5% of the parental B77-3T3 cells, demonstrating that metastatic clone precursors pre-existed, as a small minority, in the parental line. The genotypic marker appeared to be steadily associated with the metastatic phenotype since, after prolonged in vitro propagation, the subclones retained both the marker chromosome and the high metastatic potential. Although the marker chromosome was constantly present, chromosomal numerical and structural aberrations were also found in 20% of the long-term-propagated subclone cells, supporting the suggestion that metastatic properties are associated with cytogenetic instability.  相似文献   
3.
The study describes practices relating to syringe acquisition and disposal by Syringe Exchange Programme (SEP) participants. A cross-sectional multi-city study enrolled 857 injection drug users (IDUs) from six SEPs in different Brazilian regions, and assessed self-reported acquisition and disposal behaviours. Seven hundred and nine males (82.9%) and 146 females (17.1%) were recruited through outreach and interviewed, most from the streets or their neighbourhoods (54.1%). The average age was 28.5 years; 76.4% reported injecting cocaine in the past 6 months. Sources for acquiring new syringes differed significantly between time of injection drug use debut and the 6 months prior to interview. Fifty-three percent of IDUs reported acquiring their syringes in pharmacies when they initiated injection drug use, whereas most reported acquiring new syringes in the 6 months before interview from several simultaneous sources: 69% through SEPs; 58% through pharmacies; 36% from friends and/or sexual partners; and 17% from other health services. Across SEPs, acquisition and disposal varied widely. Most interviewees discarded their syringes on the streets, in open fields, or in the garbage or sewage. Restrictions on syringe availability and unsafe practices may be functioning as barriers to the public health recommendation of one-time use of sterile syringes for IDUs and discouraging community support to SEPs. Further increase in access to legal, inexpensive and timely sterile syringes, as well as counselling about the merits of one-time use and safer disposal must be reinforced as part of efforts to minimise high-risk behaviours and curb the spread of blood-borne infections.  相似文献   
4.

Background

Gliadins are involved in gluten-related disorders and are responsible for the alteration of the cellular redox balance. It is not clear if the gliadin-related oxidative stress can induce DNA damage in enterocytes.

Aim

To investigate any possible genotoxicity caused by gliadin and to assess its relationship with oxidative stress in vitro and ex vivo.

Methods

Caco-2 cells were exposed for 6–12–24?h to increasing concentrations (250?μg/mL–1000?μg/mL) of digested gliadin. We investigated: cytotoxicity, oxidative balance (reactive oxygen species, ROS), DNA damage (comet assay and γ-H2AX detection), transglutaminase type 2 (TG2) activity and annexin V expression. H2AX and 8-OHG immunohistochemistry has been evaluated on duodenal biopsies of celiac subjects and controls.

Results

Gliadin induced a significant increase (+50%) of ROS after 12?h of exposition starting with a 500?μg/mL dose of gliadin. Comet assay and γ-H2AX demonstrated DNA damage, evident at the gliadin concentration of 500?μg/mL after 24?h. TG2 activity increased in chromatin and cytoskeleton cellular compartments at different gliadin doses (250/500/1000?μg/mL). The γ-H2AX and 8-OHG immunohistochemistry was altered in the duodenal biopsies of celiac patients.

Conclusions

Gliadin induces cellular oxidative stress, DNA damage and pro-apoptotic stimulation in Caco-2 cells and in the duodenal mucosa of celiac patients.  相似文献   
5.
Chromosome 1 C-band length mosaicism was detected in lymphocytes from six tumor patients and one healthy subject belonging to three families with a high incidence of cancer. In all cases the variant cell population showed a decreased amount of C-heterochromatin in one chromosome, whereas the C-banded pattern of the homolog was identical to that of the nonvariant cell population. A family tendency to unequal mitotic crossing over, possibly leading to C-band heteromorphism, may explain the high frequency of detection of C-heterochromatin mosaicism in cancer family members (seven of 13 cases studied). The possible role of heterochromatin in inducing cancer has been widely discussed. The special feature of the acquired C-band variants vis-à-vis the inherited ones is that they mark intrinsic genetic instability that may result, through multiple mechanisms, in increased susceptibility to malignancy.  相似文献   
6.
Fluorescence In Situ Hybridization (FISH) studies with chromosome-specific libraries and repetitive probes were performed on the human acute myeloid leukemia cell line GF-D8 in order to define the complex chromosomal rearrangements observed by conventional cytogenetic analysis. Two-colour FISH with whole chromosome painting probes 8 and 11 showed that the add(8) chromosome had an 11-derived region inserted at q24, whereas the add(11) chromosome had an 8-derived region translocated onto q23. It also demonstrated that no normal chromosome 11 is present in GF-D8 cells, since a translocation involving chromosomes 11 and 17q was detected in addition to the add(11). The der(7) chromosome with extra material in its long arm, identified by QFQ and GTG banding, turned out to have a chromosome 15-derived segment translocated to q22. The deletion of 7q was proved to be interstitial, as the 7q-specific telomere as well as a tiny 7-specific band were observed on an unknown chromosome. Fine mapping of the breakpoints involved in the multiple chromosomal rearrangements of the GF-D8 cell line might provide insights into the mechanisms of myeloid leukaemogenesis.  相似文献   
7.
Background The significance of the presence of anti-gliadin antibodies in patients affected by celiac disease is still unclear. It is hypothesized that gliadin deamidation, catalysed by transglutaminase, plays a role in favoring the antigen presentation. Aim To determine the immunoreactivity of anti-gliadin antibodies from untreated celiac patients to transglutaminase deamidated gliadins. Materials and methods Gliadins from wheat flour underwent enzymatic digestion and were deamidated or cysteamine-transamidated by transglutaminase. Immunoreactivity of anti-gliadin antibodies from untreated adult celiac patients sera was evaluated by means of a competitive enzyme-linked immunosorbent assay (ELISA) method. Results Gliadin deamidation increased antibodies immunoreactivity from 25% to 50% while cysteamine incorporation into the gliadin peptides resulted in an immunoreactivity decrease. Conclusions Increased immunoreactivity of transglutaminase deamidated gliadins tested with anti-gliadin antibodies from untreated adult celiac patients supports the hypothesis of a pivotal role of gliadin deamidation in the pathomechanism of celiac disease.  相似文献   
8.
A single copy of a der 15 chromosome (m3) characterized by a C- and distamycin A-Dapi-positive region was observed in the -Y hyperploid karyotype of a primary human melanoma (Me 1402). The heterochromatic region was located pericentromerically, adjacent at one end to the NOR region of chromosome 15, and at the other to an unclassifiable chromosomal piece. We established that the C-positive block in the marker chromosome originated from Y heterochromatin by high-stringency in situ hybridization with a DNA probe for the 2.1 Hae III Y-specific repeat. Loss of the Y chromosome in tumors has been considered to be a secondary event associated with malignant evolution. It is significant that Me 1402 cells, which are highly malignant, lack the Y chromosome, but retain its heterochromatic portion in the rearranged m3 chromosome.  相似文献   
9.
10.
CONTEXT: Neurosurgery is regarded as the first-line treatment of acromegaly. Because of its low cure rate in macro and invasive adenoma, the role of primary medical treatment is debated. OBJECTIVE: Our objective was to evaluate primary pharmacological treatment in acromegaly. DESIGN AND SETTING: We conducted an open prospective study at two Italian tertiary level centers. PATIENTS: We studied 67 consecutive patients (36 women; age, 54.9 +/- 14.2 yr; 72% bearing macroadenoma). Intervention: Individually tailored octreotide LAR (OCLAR) was administered. MAIN OUTCOME MEASURES: Outcomes included safe GH (<2.5 mug/liter), normal age-matched IGF-I levels, and tumor shrinkage. RESULTS: After a median follow-up of 48 months (range, 6-108 months), safe GH levels and normal age-matched IGF-I values were obtained by 68.7 and 70.1% of patients, respectively. Hormonal endpoints were achieved regardless of basal levels, and early results were predictive of outcome. Tumor shrank in 82.1% of patients by 62 +/- 31% (range, 0-100%), decreasing from 2101 +/- 2912 to 1010 +/- 2196 mm(3) (P < 0.0001). The higher the basal GH values and the greater the GH/IGF-I changes on treatment, the greater the tumor shrinkage. Tumor disappeared in three patients and was progressively reduced to empty sella in five patients; apparent magnetic resonance imaging cavernous sinus invasion disappeared in three. In males, testosterone increased, restoring eugonadism in 64% of hypogonadal patients. CONCLUSIONS: The efficacy on GH/IGF-I levels in unselected patients and the outstanding volumetric control indicate that treatment with OCLAR may be the first therapeutic approach to all acromegalic patients not amenable to surgical cure. Tumor shrinkage might also encourage the evaluation of primary OCLAR adoption in patients with initial visual field defects.  相似文献   
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