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111.
112.
Renal functional status in Mycobacterium leprae infected mice can be best studied by examining the enzymatic status of brush border membrane vesicles from proximal convoluted tubule. The role of vaccination in modulation of the renal status brought by the disease has been studied using this technique. The characteristic marker enzymes of renal brush border membrane--namely alkaline phosphatase, leucine aminopeptidase and gamma-glutamyl transpeptidase decreased significantly (p less than 0.01) in due course in M. leprae infection over a period of 9 months. The combined vaccine (BCG + M. leprae) may have a protective effect on renal abnormalities only in the initial stages of infection as indicated by a significant rise in enzymatic levels. However, no significant (p greater than 0.05) protective effect of vaccine was found in a more advanced disease state after 9 months in infected mice.  相似文献   
113.
Oral administration of water fraction of alcoholic extract of leaves of Vinca rosea (fam. apocynaeceae) led to marked lowering of blood glucose level in normal and streptozotocin induced diabetic rats. The hypoglycemic effect of the fraction was comparable with that of tolbutamide.  相似文献   
114.
115.
12 untreated lepromatous leprosy patients were screened for primary dapsone resistance by the uptake of labelled thymidine by macrophage resident M. leprae. There were found to harbour primary dapsone resistant strains of M. leprae and another three partially resistant strains to the drug. This rapid, simple and reliable method should be used routinely to screen leprosy patients, for drug resistance.  相似文献   
116.

Purpose

Prostate-specific membrane antigen (PSMA) is highly up-regulated in prostate tumor cells, providing an ideal target for imaging applications of prostate cancer. CTT-1297 (IC50?=?27 nM) is an irreversible phosphoramidate inhibitor of PSMA that has been conjugated to the CB-TE1K1P chelator for incorporation of Cu-64. The resulting positron emission tomography (PET) agent, [64Cu]ABN-1, was evaluated for selective uptake both in vitro and in vivo in PSMA-positive cells of varying expression levels. The focus of this study was to assess the ability of [64Cu]ABN-1 to detect and distinguish varying levels of PSMA in a panel of prostate tumor-bearing mouse models.

Procedures

CTT-1297 was conjugated to the CB-TE1K1P chelator using click chemistry and radiolabeled with Cu-64. Internalization and binding affinity of [64Cu]ABN-1 was evaluated in the following cell lines having varying levels of PSMA expression: LNCaP late-passage?>?LNCaP early passage?≈?C4-2B?>?CWR22rv1 and PSMA-negative PC-3 cells. PET/X-ray computed tomography imaging was performed in NCr nude mice with subcutaneous tumors of the variant PSMA-expressing cell lines.

Results

[64Cu]ABN-1 demonstrated excellent uptake in PSMA-positive cells in vitro, with ~80 % internalization at 4 h for each PSMA-positive cell line with uptake (fmol/mg) correlating to PSMA expression levels. The imaging data indicated significant tumor uptake in all models. The biodistribution for late-passage LNCaP (highest PSMA expression) demonstrated the highest specific uptake of [64Cu]ABN-1 with tumor-to-muscle and tumor-to-blood ratios of 30?±?11 and 21?±?7, respectively, at 24 h post-injection. [64Cu]ABN-1 cleared through all tissues except for PSMA-positive kidneys.

Conclusion

[64Cu]ABN-1 demonstrated selective uptake in PSMA-positive cells and tumors, which correlated to the level of PSMA expression. The data reported herein suggest that [64Cu]ABN-1 will selectively target and image variant PSMA expression and in the future will serve as a non-invasive method to follow the progression of prostate cancer in men.
  相似文献   
117.
The Revised International Staging System (R-ISS) and the International Myeloma Working Group 2014 (IMWG 2014) are newer staging systems used to prognosticate multiple myeloma (MM) outcomes. We hypothesized that these would provide better prognostic differentiation for newly diagnosed multiple myeloma (MM) compared with ISS. We analyzed the Center for International Blood and Marrow Transplant Research database from 2008 to 2014 to compare the 3 systems (N?=?628) among newly diagnosed MM patients undergoing upfront autologous hematopoietic cell transplantation (AHCT). The median follow-up of survivors was 48 (range, 3 to 99) months. The R-ISS provided the greatest differentiation between survival curves for each stage (for overall survival [OS], the differentiation was 1.74 using the R-ISS, 1.58 using ISS, and 1.60 using the IMWG 2014) . Univariate analyses at 3 years for OS showed R-ISS I at 88% (95% confidence interval [CI], 83% to 93%), II at 75% (95% CI, 70% to 80%), and III at 56% (95% CI, 3% to 69%; P < .001). An integrated Brier score function demonstrated the R-ISS had the best prediction for PFS, though all systems had similar prediction for OS. Among available systems, the R-ISS is the most optimal among available prognostic tools for newly diagnosed MM undergoing AHCT. We recommend that serum lactate dehydrogenase and cytogenetic data be performed on every MM patient at diagnosis to allow accurate prognostication.  相似文献   
118.
Little is known about the experiences of individuals donating peripheral blood stem cells (PBSCs) or marrow for a second time. To study this, unrelated donors making a second donation through the National Marrow Donor Program between 2004 and 2013 were evaluated. Experiences of second-time donors giving marrow (n?=?118: first donation was PBSC in 76 and marrow in 42) were compared with those making only 1 marrow donation (n?=?5829). Experiences of second-time donors giving PBSCs (n?=?602) (first donation was PBSCs in 362; marrow in 240) were compared to first-time PBSC donors (n?=?16,095). For donors giving a second PBSC or marrow donation there were no significant differences in maximum skeletal pain, maximum symptoms measured by an established modified toxicity criteria, and recovery time compared with those who donated only once. Notably, the yield of marrow nucleated cells and PBSC CD34+ cells with second donations was less. As previously noted with single first-time donations, female (PBSCs and marrow) and obese donors (PBSCs) had higher skeletal pain and/or toxicity with a second donation. PBSC donors who experienced high levels of pain or toxicity with the first donation also experienced high levels of these symptoms with their second donation and slower recovery times. In conclusion, for most donors second donation experiences were similar to first donation experiences, but CD34+ yields were less. Knowledge of the donor's first experience and stem cell yields may help centers decide whether second donations are appropriate and institute measures to improve donor experiences.  相似文献   
119.
Erythrocyte antioxidants catalase, superoxide dismutase, reduced glutathione and glutathione peroxidase were studied in cells harbouring different growth stages of Plasmodium falciparum. Catalase and superoxide dismutase showed significant decrease during parasite maturation indicating hampered metabolism of hydrogen peroxide and superoxide anions. Glutathione peroxidase also exhibited a downward trend during the growth of P. falciparum, while there was a moderate accumulation of reduced glutathione. These findings suggest decreased utilization of the reduction potential in detoxification of reactive oxygen species. The fall in all three antioxidant enzymes studied was highly significant (P less than 0.001) in erythrocytes with mature stages of the parasite (trophozoites, schizonts). The increased vulnerability of erythrocytes to damage, which parallels the growth phases of the parasite emphasizes the need for early treatment of P. falciparum malaria to minimise red cell destruction and the resulting anaemia.  相似文献   
120.
High-dose therapy (HDT) and autologous hematopoietic cell transplantation (auto-HCT) has been anecdotally prescribed in gray zone lymphoma (GZL), showing encouraging efficacy. We conducted a multicenter retrospective study aimed at assessing outcomes after auto-HCT in 32 patients with GZL treated at 9 transplantation centers in the United States. The median age of patients at transplantation was 38 years (range, 18 to 70 years), and the majority were male (n?=?21; 66%). The median number of lines of therapy before transplantation was 2 (range, 1 to 4). BEAM was the most commonly prescribed regimen (n?=?23; 72%). The median duration of follow-up for surviving patients was 34 months (range, 1 to 106 months). Median overall survival (OS) was not reached. The 3-year progression-free survival (PFS) and OS for all patients were 69% and 78%, respectively. Three-year PFS and OS were 100% for patients who received only 1 line of therapy before auto-HCT versus 65% (PFS, P?=?.25) and 75% (OS, P?=?.39) for those receiving >1 line. The cumulative incidence of relapse/progression was 4% at 1 year post-transplantation and 31% at 3 years post-transplantation. The 3-year nonrelapse mortality was 0%. These findings suggest that HDT and auto-HCT is an effective treatment in patients with GZL. Our findings ideally require confirmation in a larger cohort of patients, preferably in the setting of large prospective multicenter randomized controlled trials. However, we acknowledge that such studies could be difficult to conduct in patients with GZL owing to the disease's rarity. Alternatively, a multicenter prospective study that includes tissue banking and a data registry is warranted to help better understand the biology and natural history of the disease.  相似文献   
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