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1.
Biodistribution of iodine-131-labeled Lipiodol Ultra-Fluide (I-131 LUF) injected into the hepatic artery was studied scintigraphically in 47 patients with hepatocellular carcinoma (n = 23), hepatic metastases (n = 14), or normal livers (n = 10). The investigation was extremely well tolerated. I-131 LUF concentrated mainly in the liver (L) and the lungs (l), with L/L + l activity ratios greater than 75% for all three groups of patients. I-131 LUF distribution was homogeneous in normal livers and heterogeneous in cirrhotic livers. I-131 LUF concentrated in the tumor with a tumorous (T) to nontumorous (NT) activity ratio (T/NT) of 4.3 +/- 3.6 for hepatocellular carcinoma and 2.4 +/- 0.7 for hepatic metastases. The effective half-life of I-131 LUF is more than 4.5 days for the three groups. It was eliminated mainly through the urine. Clearance from tumor is slower than from normal liver, as shown by the increase in T/NT at day 18. Biodistribution did not change in patients who had a second injection, which indicates that there is no saturation phenomenon. The results of this study suggest that LUF may be considered as a potential carrier vehicle for therapeutic agents.  相似文献   
2.
Jumping translocations (JT) have been defined as nonreciprocal translocations involving a same donor chromosome arm or chromosome segment onto two or more recipient chromosomes in different cell lines in the same patient, leading to a mosaic karyotype. This definition has been expanded to also include extra copies of a same donor segment on different recipient chromosomes in a single clone. Six patients with multiple myeloma and JT involving chromosome arm 1q were identified among 37 patients presenting with chromosome 1 abnormalities. All six patients had an advanced disease and a short survival. The literature review allowed us to identify 24 additional patients with JT. Chromosomes 16 and 19 were the recipients in 11 (45.8%) and 6 (25%) of these 24 patients, respectively. Breakpoints on the recipient chromosomes were pericentromeric in 46.2% and telomeric in 40.4% of the breakpoints recorded. Since telomeres are made of (TTAGGG)n tandem DNA repeats that are also found in the pericentromeric heterochromatic regions (interstital telomeric sequences), it is presumed that jumping translocations arise through illegimate recombination between telomere repeat sequences and interstitial telomeric sequences.  相似文献   
3.
BACKGROUND: Several studies have shown an increased frequency of constitutional chromosome aberrations in male and female partners of couples examined prior to ICSI. We conducted a cohort study to determine whether there was an increase in numerical sex chromosome mosaicism among couples undergoing ICSI compared with fertile couples. METHODS: Cytogenetic investigations were performed in 228 females and 208 males seen for ICSI between January 1997 and March 2001. They were matched to control females and males. RESULTS: Sex chromosome loss or gain was observed in at least one cell from 24.1% of ICSI women in comparison with 22% of controls (not significant). A significant difference between these two groups was found when X chromosome loss in at least two cells was considered, 9.6% for ICSI females versus 4.8% for controls (P = 0.01). No significant difference was observed between male groups concerning loss or gain of the X or Y chromosome. CONCLUSION: Our results support previously published studies indicating that the loss of an X chromosome in a single cell in females undergoing ICSI is probably an artefact. However, they suggest that a woman could have true sex chromosome mosaicism when two 45,X0 cells are found.  相似文献   
4.
Antivirulence strategies targeting bacterial behavior, such as adhesion and biofilm formation, are expected to exert low selective pressure and have been proposed as alternatives to biocidal antibiotic treatments to avoid the rapid occurrence of bacterial resistance. Here, we tested this hypothesis using group 2 capsule polysaccharide (G2cps), a polysaccharidic molecule previously shown to impair bacterium-surface interactions, and we investigated the nature of bacterial resistance to a nonbiocidal antibiofilm strategy. We screened an Escherichia coli mutant library for an increased ability to form biofilm in the presence of G2cps, and we identified several mutants displaying partial but not total resistance to this antibiofilm polysaccharide. Our genetic analysis showed that partial resistance to G2cps results from multiple unrelated mutations leading to modifications in surface physicochemical properties that counteract the changes in ionic charge and Lewis base properties induced by G2cps. Moreover, some of the identified mutants harboring improved biofilm formation in the presence of G2cps were also partially resistant to other antibiofilm molecules. This study therefore shows that alterations of bacterial surface properties mediate only partial resistance to G2cps. It also experimentally validates the potential value of nonbiocidal antibiofilm strategies, since full resistance to antibiofilm compounds is rare and potentially unlikely to arise in clinical settings.  相似文献   
5.
Only limited population-based data are available on mantle cell lymphoma (MCL), a relatively rare and aggressive mature B cell non-Hodgkin lymphoma (NHL) entity. We conducted an epidemiological study based on the three French registries devoted to haematological malignancies over the period 2002–2006. Main clinical features and management characteristics were collected. Incidence and survival rates were estimated, and independent prognostic factors were analysed. MCL was diagnosed in 135 patients between 2002 and 2006. Seventy-four percent of patients were men. Age-standardised incidence rate of MCL (per 100,000) was 1.1 in men and 0.26 in women. Median age at diagnosis was 72 years (range 30–92). Advanced-stage (III or IV) disease was diagnosed in 81.5 % of patients, and 55 % of them were identified as high risk according to MCL International Prognostic Index (MIPI). Median net survival time was 41 months (95 % confidence interval (CI), 38–62). Main independent prognostic factors were age at diagnosis, performance status and use of rituximab in first-line treatment. Median overall survival was 36 months (95 % CI, 27–40) for high MIPI and 60 months (95 % CI, 35–74) for low/intermediate MIPI patients (p?=?0.02). This study confirms that MCL remains an aggressive NHL with a median overall survival less than 4 years and demonstrates that the use of rituximab has modified overall survival duration.  相似文献   
6.
Melanoma in children is rare. Nevertheless, it is imperative that clinicians be aware that melanoma does occur in childhood. Yet there is very little information available on the clinico-pathologic variations, and the prognostic parameters of melanoma in children. This report presents the results of a multicenter study of 102 lesions originally diagnosed as cutaneous melanoma, conducted among 5 Western European countries and collected during the period 1961–1994. Criteria for inclusion in the study included: (1) diagnosis of cutaneous melanoma; (2) age up to 16 years at diagnosis; and (3) availability of representative microscopic slides. On the basis of the histologic review only, 60 lesions were confirmed as melanoma, and 42 lesions initially diagnosed as melanoma were reclassified as nevi; 31 of the latter contained a predominance of spindle cells. The only significant parameter associated with the development of metastases or fatal outcome was thickness of more than 2.00 mm. The 5-year survival rate observed in this study was 84%. Based on these findings we conclude that considerable over-diagnosis of melanomas in children occurs. In order, therefore, to give consistent epidemiological data on melanomas in children and to improve proper recognition of their diagnostic features, both by clinicians and by pathologists, we propose to set up a central registry of melanomas in children in Europe, under the auspices of the European Organization for Research and Treatment of Cancer. © 1996 Wiley-Liss, Inc.  相似文献   
7.
Although intra-arterial radiotherapy with 131I-labelled lipiodol is a useful therapeutic approach in the treatment of hepatocellular carcinomas, various disadvantages limit its use. Here we describe the development of 188Re-SSS lipiodol, as well as its biodistribution in the healthy pig after injection into the hepatic artery. The 188Re-SSS lipiodol was obtained after dissolving a chelating agent, previously labelled with 188Re, in cold lipiodol. The radiochemical purity (RCP) of the labelling was checked immediately and at 24 and 48 h. The 188Re-SSS lipiodol was injected into the hepatic artery of six healthy pigs. They were killed 1, 24 and 48 h post injection, for ex vivo counting. An autoradiographic study was performed in three cases. 188Re-SSS lipiodol was obtained with a yield of 87%±9.1%. The immediate RCP was 93%±3.4%. This radiolabelling was reproducible and stable at 48 h in plasma: 90.6%±1.5% of the activity remained in the lipiodol with an RCP of 91%±4%. Ex vivo counting confirmed the predominantly hepatic uptake and revealed weak lung and intestinal uptake. There was very weak urinary elimination (2.3%±0.5% at 48 h) and a slightly higher level of intestinal elimination (4.8%±1.9% at 48 h). The autoradiographic studies showed 188Re-SSS lipiodol to be located mainly in sinusoids, like 131I-lipiodol. By using the method described here, 188Re-SSS lipiodol can be obtained with a very high yield and a satisfactory RCP. Its biodistribution in the healthy pig is in agreement with data published elsewhere concerning other types of radiolabelling used for lipiodol, except for the very weak urinary and intestinal elimination, which probably indicates better stability of 188Re-SSS labelling.  相似文献   
8.
The most informative for differential diagnosis parameters (surface and nucleus polarization) were determined on the basis of morphometric analysis of 42 cytograms of invasive duct cancer (IDC) and 39 cytograms of invasive lobular breast cancer (ILC) using the computer analyzer MEKOC-C. Combination of these two parameters allowed the authors to elaborate a decisive rule for differential diagnosis of these two cancers (the mistake is reduced to 8.6%). The analysis of 8 informative morphometric nuclear parameters has shown that in ILC the nuclei are more monomorphic, less in square and perimeter, nucleoli are less numerous than in IDC. The study gives objective criteria for preoperative differential cytological diagnosis between IDC and ILC.  相似文献   
9.
10.
Prognosis of patients with renal cell carcinoma (RCC) is mainly determined by metastases. The understanding of the metastatic process will give the basis for a differential diagnosis leading to an individual prognosis and to new therapeutical strategies. In order to define specific genetic alterations which are common in renal cancer metastases of the lung, we performed comparative genomic hybridization (CGH) on metastases and in some cases on their related primary renal tumors. For CGH, DNA was isolated from 2 or 5 paraffin sections (5 micro m). Tumor and normal (control) DNAs were amplified by DOP-PCR and labeled with biotin-dUTP and digoxigenin-dUTP, respectively. Hybridization and detection were carried out according to standard protocols. In 33 out of 40 metastases, genetic alterations were detected, most frequently these were losses of chromosomes 3p (74%), 8p (31%), 9 or 9q (34%), 14 [26%, 18q (40%) and gains of chromosome 5/5q 34%], 7 (31%) and 12 (26%). Combination of loss of 8p and gain of 8q occurred frequently. The mean number of aberrations per tumor was 8.1 (1-11). The comparison of alterations in related primary and metastatic tumors showed identical alterations in 5 out of 8 cases. This study demonstrates, that lung metastases from renal cell carcinoma are characterized by an accumulation of specific genetic alterations which show a clonal relationship to the related primary tumors.  相似文献   
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