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1.
We compared the performance of two UltraSensitive AMPLICOR HIV-1 MONITOR kits (version 1.5 [v1.5] versus v1.0) by retesting 404 plasma samples with low viral loads (<3,000 copies/ml) with both kits. With 292 samples that initially had <50 copies/ml by the v1.0 kit, the v1.5 assay was more sensitive than the v1.0 assay for samples with human immunodeficiency virus type 1 RNA near the 50-copy/ml cutoff (P = 0.0146). Median numbers of copies per milliliter were similar for 112 samples with 50 to 3,000 copies/ml with no difference in sensitivity with a 200-copy/ml cutoff.  相似文献   
2.
Peripheral blood mononuclear cell surface markers were studied in a series of 26 hairy cell leukaemia patients 19 of whom were splenectomized previously. Patients with non-symptomatic and stable disease were distinguished from those with symptomatic and/or progressive disease (also termed "active" clinical stages). In all HCL patients as a group, the absolute number of CD4+ MN cells did not differ statistically from that of the controls, while the number of CD8+ MN cells was significantly increased. The reduction of the CD4/CD8 ratio in the peripheral blood of HCL patients as compared to the controls was explained by the reduction of this ratio in patients with "active disease", while the CD4/CD8 ratio of patients with non-symptomatic and stable disease did not differ statistically from that of the controls. The CD4/CD8 ratio was found to be influenced mainly by the clinical stage of the disease, and not by the effect of splenectomy.  相似文献   
3.
The potential of using a chemically synthesized oligodeoxynucleotide as a diagnostic probe to detect human papillomavirus type 16 (HPV-16) in genital infections was evaluated by comparing it with a cloned full-length HPV-16 probe in dot-blot DNA hybridizations. An oligonucleotide sequence, 20 bases in length from the E6 region of HPV-16 (E6 oligo) and different from the DNA sequences of HPV types 6, 11 and 18 by at least 2 base pairs, was chosen for chemical synthesis. The oligoprobe, which was 5'-end labelled with [32P]dATP, was found to be specific, but approximately ten times less sensitive than the full-length radiolabelled probe of HPV-16, in dot-blot hybridizations with the DNA of HPV-6, -11, -16 and -18, HPV positive and negative cell-lines. From 36 cervical or vulval scrapes two samples were found positive with both cloned HPV-16 and oligoprobe hybridization. Of 21 samples of formalin-fixed, paraffin-embedded squamous cell carcinomas originating from anus, oesophagus, penis, colon, breast and skin only 4 anal squamous cell carcinomas were positives when hybridized with cloned HPV-16 DNA or with the oligoprobe. This study confirms that HPV-16, which is frequently associated with squamous cell carcinoma of the cervix is also strongly associated with squamous cell carcinoma of the anus.  相似文献   
4.
We have delineated regions of interest at chromosome 2q21.2, 2q36.3, and 2q37.1 by deletion mapping of 114 urothelial cancers (UC). Altogether, 17%, 18%, and 63% of the G1, G2, and G3 tumors displayed loss of heterozygosity at chromosome 2q, respectively, The region at 2q21.2 was narrowed down to the LRP1B gene (NT_005129.6). Hemi- and homozygous deletion at the LRP1B gene region was seen in 31 of 114 UCs. Only 8% of the UCs with G1 and none with G2 tumors showed loss of heterozygosity at the LRP1B gene, whereas 49% of the G3 UCs had allelic loss at this region. RT-PCR analysis of the LRP1B gene showed the lack of expression of several exons in 2 of 9 cases analyzed. Our analysis suggests that the LRP1B gene is a candidate tumor suppressor gene in UCs.  相似文献   
5.
Yersinia pestis, the etiologic agent of plague is a highly invasive organism being able to invade non-phagocytic epithelial cells. Its plasminogen activator (Pla), encoded by the pPCP1 plasmid plays a pivotal role in internalisation of bacteria by HeLa cells. The aim of this study was to analyse the intracellular signalling processes and cytoskeletal rearrangement events associated with invasion. Wortmannin caused a 50% decrease of invasiveness at 50nM concentration pointing to the involvement of phosphatidyl-inosinol-4 kinase (PtINs4). Pre-treatment with staurosporin, a potent inhibitor of protein kinases (PKs) and with genistein, a specific tyrosine kinase inhibitor decreased the number of internalised bacteria about seven-fold and two-fold, respectively, indicating the involvement of PKs including tyrosine kinases in Pla-mediated internalisation. Cytochalasin D, an actin polymerisation inhibitor, C3 exoenzyme of Clostridium botulinum, a specific inhibitor of small GTPase Rho, and NDGA, a 5-lipoxygenase inhibitor also involved in Rho activation strongly reduced the number of internalised bacteria revealing the role of cytoskeletal events in the invasion process. All the tested inhibitors changed the invasion but not the adhesion pattern of the Pla producing recombinant strain. Actin rearrangement could also be visualised also with rhodamin-phalloidin staining.  相似文献   
6.
The dexamethasone suppression test (DST) and response to two different antidepressant drugs (maprotiline as a specific noradrenergic, and amitriptyline as a predominantly serotoninergic drug) were investigated in 44 endogenously depressed female inpatients. The more anxious and/or agitated patients were mostly treated with amtiriptyline, the non-anxious and retarded patients with maprotiline. It was found that among maprotiline responders (N = 15) there were significantly more abnormal DSTs and postdexamethasone serum cortisol levels were significantly higher than among amitriptyline responders (N = 16). On the other hand, DST abnormalities among amitriptyline non-responders (N = 10) were similar to those among maprotiline responders. The results confirm earlier reports by Brown et al. (1980), Ettigi et al. (1983) and Fraser (1983) and indicate that abnormal DST may identify the "noradrenergic" subtype of endogenous depression and that the DST represents a good way of selecting a specific antidepressant drug for the treatment of endogenously depressed patients.  相似文献   
7.
Some pathological findings and prognostic indices recorded in breast cancer cases, detected, on one hand, by a provider-initiated mammography screening program (Group 1), and, opportunistically, in self-referred symptomatic women (Group 2) on the other, are compared. In 8877 symptom-free women, aged 50-65 years, individually invited to attend the screening offered for the residents of the III., XII. and XIII. districts of Budapest, 67 cancer cases were detected (7.5 in 1000 screenees), in accordance with the cancer detection rate of the first, "prevalence" round of organised screening programmes. In the other group of 1593 symptomatic, self-referred women of the same age, 113 cancer cases were diagnosed by mammography. As far as the pathological parameters are concerned, the number of cases with invasive cancer less than 15 mm in diameter, and those with axillary nodes present was found to be significantly higher in the screened group as compared to the self-referred one (p < 0.01). In "small" cancers (i.e. less than 15 mm in diameter), no significant difference was found in the proportion of histologic grade III tumours among the two groups. In screen-detected cancers both the morphometric prognostic index (as calculated by Baak et al.) and the Nottingham Prognostic Index (NPI) proved to be more favourable, as compared to those in the self-referred group. The p-value as determined by Mann-Whithey test was 0.000003 in the screened group, and 0.000015 in the other one. These findings provide convincing evidence in support of the public health importance of provider-initiated, organised mammography screening for breast cancer, therefore, the introduction on service basis of organised breast screening into the health care system in Hungary is strongly recommended by the authors.  相似文献   
8.
Martin S. Hirsch, MD; Françoise Brun-Vézinet, MD; Richard T. D'Aquila, MD; Scott M. Hammer, MD; Victoria A. Johnson, MD; Daniel R. Kuritzkes, MD; Clive Loveday, MD, PhD; John W. Mellors, MD; Bonaventura Clotet, MD, PhD; Brian Conway, MD; Lisa M. Demeter, MD; Stefano Vella, MD; Donna M. Jacobsen; Douglas D. Richman, MD

JAMA. 2000;283:2417-2426.

Objective  Assays for drug resistance testing in human immunodeficiency virus type 1 (HIV-1) infection are now available and clinical studies suggest that viral drug resistance is correlated with poor virologic response to new therapy. The International AIDS Society–USA sought to update prior recommendations to provide guidance for clinicians regarding indications for HIV-1 resistance testing.

Participants  An International AIDS Society–USA 13-member physician panel with expertise in basic science, clinical research, and patient care involving HIV resistance to antiretroviral drugs was reconvened to provide recommendations for the clinical use of drug resistance testing.

Evidence and Consensus Process  The full panel met regularly between January and October 1999. Resistance and resistance testing data appearing in the last decade through April 2000 and presentations at national and international research conferences were reviewed. Recommendations and considerations were developed by 100% group consensus, acknowledging that definitive data to support final recommendations are not yet available.

Conclusions  Emerging data indicate that despite limitations, resistance testing should be incorporated into patient management in some settings. Resistance testing is recommended to help guide the choice of new regimens after treatment failure and for guiding therapy for pregnant women. It should be considered in treatment-naive patients with established infection, but cannot be firmly recommended in this setting. Testing also should be considered prior to initiating therapy in patients with acute HIV infection, although therapy should not be delayed pending the results. Expert interpretation is recommended given the complexity of results and assay limitations.

  相似文献   

9.
During diagnostic workflow when detecting sequence alterations, sometimes it is important to design an algorithm that includes screening and direct tests in combination. Normally the use of direct test, which is mainly sequencing, is limited. There is an increased need for effective screening tests, with “closed tube” during the whole process and therefore decreasing the risk of PCR product contamination. The aim of this study was to design such a closed tube, detection probe based screening assay to detect different kind of sequence alterations in the exon 11 of the human c-kit gene region. Inside this region there are variable possible deletions and single nucleotide changes. During assay setup, more probe chemistry formats were screened and tested. After some optimization steps the taqman probe format was selected.  相似文献   
10.
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