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71.
Abstract

Contribution to the Myxomycetes flora of Italy. — In this work 52 species, 20 of which new to Italy, are named. The specimens were collected in northern and central Italy.  相似文献   
72.
Recent intervention studies revealed that supplementation with retinoids resulted in a higher incidence of lung cancer. Recently the causal mechanism has begun to be clarified. We report here that retinol caused cellular oxidative stress and modulated superoxide dismutase, catalase and glutathione peroxidase activities. Retinol (7 μM) significantly increased TBARS, conjugated dienes, and hydroperoxide-initiated chemiluminescence in cultured Sertoli cells. In response to retinol treatment superoxide dismutase, catalase and glutathione peroxidase activities increased. TBARS content and catalase activities were decreased by a free radical scavenger. These findings suggest that retinol may induce oxidative stress and modulate antioxidant enzyme activities in Sertoli cells.  相似文献   
73.
Heteropteran legs are very diverse within and among taxa, and such variation is frequently correlated with life habits. Structural modifications are commonly present in the legs of the Pentatomoidea but are poorly studied. Using scanning electron microscopy, the tibia and pretarsal microstructure of 82 species of Pentatomidae (Heteroptera), three species of Scutelleridae, and ten species of Thyreocoridae were described, focusing on the pretarsal structure, the foretibial apparatus, and the foretibial comb. The Pentatomidae, the Scutelleridae, and the Thyreocoridae have uniform pretarsal structures. Variation can be found in the length of the parempodial setae and in the shape of the parempodial projections. The foretibial combs of the Pentatomidae, the Thyreocoridae, and the Scutelleridae are described for the first time, and we have demonstrated that there is low structural variation in the foretibial comb complex of the studied species. The setae organization and distribution on the foretibial apparatus is uniform in the families studied. However, the Asopinae (Pentatomidae) bear a foretibial apparatus that is uniquely organized. The taxonomic and phylogenetic relevance of the pretarsal traits, the foretibial apparatus, and the foretibial comb are discussed.  相似文献   
74.

Introduction

The aim of this study was to evaluate the safety, pharmacokinetics, and clinical response of brodalumab (AMG 827), a human, anti-IL-17 receptor A (IL-17RA) monoclonal antibody in subjects with moderate-to-severe rheumatoid arthritis (RA).

Methods

This phase Ib, randomized, placebo-controlled, double-blind multiple ascending dose study enrolled subjects with moderate to severe RA (≥6/66 swollen and ≥8/68 tender joints). Subjects were randomized 3:1 to receive brodalumab (50 mg, 140 mg, or 210 mg subcutaneously every two weeks for 6 doses per group; or 420 mg or 700 mg intravenously every 4 weeks for two doses per group) or placebo. Endpoints included incidence of adverse events (AEs) and pharmacokinetics. Exploratory endpoints included pharmacodynamics, and improvements in RA clinical metrics.

Results

Forty subjects were randomized to investigational product; one subject discontinued due to worsening of RA (placebo). The study was not designed to assess efficacy. AEs were reported by 70% (7/10) of placebo subjects and 77% (22/30) of brodalumab subjects. Three serious AEs were reported in two subjects; there were no opportunistic infections. Brodalumab treatment resulted in inhibition of IL-17 receptor signaling and receptor occupancy on circulating leukocytes. No treatment effects were observed with individual measures of RA disease activity. On day 85 (week 13) 37% (11/30) of brodalumab subjects and 22% (2/9) of placebo subjects achieved ACR20; 7% (2/30) brodalumab subjects and 11% (1/9) of placebo subjects achieved ACR50; and 0% (0/30) brodalumab subjects and 0% (0/9) of placebo subjects achieved ACR70.

Conclusions

Multiple dose administration of brodalumab was tolerated in subjects with active RA. There was no evidence of a clinical response to brodalumab in subjects with RA.

Trial registration

ClinicalTrials.gov, NCT00771030  相似文献   
75.
A review of the literature was performed to summarize current evidence regarding the efficacy of topical immunotherapy and chemotherapy for upper urinary tract urothelial cell carcinoma (UUT-UCC) in terms of post-treatment recurrence rates. A Medline database literature search was performed in March 2012 using the terms upper urinary tract, urothelial cancer, bacillus Calmette-Guérin (BCG), and mitomycin C. A total of 22 full-text articles were assessed for eligibility, and 19 studies reporting the outcomes of patients who underwent immunotherapy or chemotherapy with curative or adjuvant intent for UUT-UCC were chosen for quantitative analysis. Overall, the role of immunotherapy and chemotherapy for UUT-UCC is not firmly established. The most established practice is the treatment of carcinoma in situ (CIS) with BCG, even if a significant advantage has not yet been proven. The use of BCG as adjuvant therapy after complete resection of papillary UUT-UCC has been studied less extensively, even if recurrence rates are not significantly different than after the treatment of CIS. Only a few reports describe the use of mitomycin C, making it difficult to obtain significant evidence.Key words: Upper urinary tract, Urothelial cell carcinoma, Bacillus Calmette-Guérin, Mitomycin C, Chemotherapy, ImmunotherapyAccording to the 2011 update of the European Guidelines for the diagnosis and management of upper urinary tract urothelial cell carcinoma (UUT-UCC),1 urothelial carcinomas are the fourth most common tumors after prostate and breast cancer, lung cancer, and colorectal cancer. Bladder tumors account for 90% to 95% of urothelial carcinomas; UUT-UCC are relatively uncommon and account for only 5% to 10% of urothelial carcinomas. The annual incidence of UUT-UCC in Western countries is approximately one or two new cases per 100,000 inhabitants. Pyelocaliceal tumors are approximately twice as common as ureteral tumors. In 8% to 13% of cases, concurrent bladder cancer is present, and 60% of UUT-UCC are invasive at diagnosis, compared with only 15% of bladder tumors. This kind of carcinoma has a peak incidence in people in their 70s and 80s, with a higher prevalence in men.Radical nephroureterectomy (RNU) with excision of the bladder cuff represents the gold standard treatment for UUT-UCC, regardless of the location of the tumor in the upper urinary tract.1 Lymph node dissection associated with RNU is of therapeutic interest and allows for optimal staging of the disease.Conservative surgery for low-risk UUT-UCC allows for preservation of the upper urinary renal unit; conservative management can be considered in imperative cases (renal insufficiency, solitary functional kidney) or in elective cases (ie, when the contralateral kidney is functional) for low-grade, low-stage tumors. Endoscopic ablation can be considered if a flexible ureteroscope, laser generator, and pliers (pluck) for biopsies are available, if the patient is informed of the need for closer follow-up, and if a complete resection is advocated.Segmental ureteral resection with wide margins provides adequate pathologic specimens for definitive staging and grade analysis while also preserving the ipsilateral kidney. Segmental resection is possible for the treatment of low- and high-risk tumors of the distal ureter, whereas segmental resection of the iliac and lumbar ureter is associated with a greater failure rate. Open resection of tumors of the renal pelvis or calices has almost disappeared.Percutaneous management can be considered for low-grade or noninvasive UUT-UCC that are inaccessible or difficult to manage by ureteroscopy, even if a theoretical risk of seeding exits in the puncture tract and if perforations occur during the procedure.After conservative treatment of UUT-UCC or for the treatment of carcinoma in situ (CIS), the instillation of bacillus Calmette-Guérin (BCG) or mitomycin C (MMC) is technically feasible by means of a percutaneous nephrostomy or even through a ureteric stent.Different agents have been used for topical therapy, including BCG, MMC, epirubicine, and thiotepa. Topical chemotherapeutic agents can be administered after endoscopic management, whereas instillations of BCG need to be postponed until the urothelium heals to avoid systemic side effects.According to a recent review,2 topical therapy appears to be safe, although its efficacy is debatable. Complications from the administration of topical immunotherapy or chemotherapy can be avoided by maintaining low intracavitary pressures during administration. Renal function does not seem to be impaired after instillation of BCG or MMC.3 No systemic side effects result from perfusion with MMC, and persistent fever was reported in 5% of patients in combined major series after BCG administration; therefore, this side effect was resolved with appropriate antimicrobial therapy in all cases. Furthermore, up to 25% of patients may have granulomatous involvement of the urinary tract after BCG.This review summarizes current evidence about the efficacy of topical immunotherapy and chemotherapy in terms of post-treatment recurrence rates.  相似文献   
76.
77.
The glyceraldehyde-3-phosphate dehydrogenase promoter of the food yeast Candida utilis strain NRRL Y-660 was cloned to create a novel integrative vector for Agrobacterium tumefaciens-mediated transformation. The new binary vector harbors β-glucuronidase activity as reporter and kanamicin/geneticin resistance as selection marker. Recombinant clones of A. tumefaciens show kanamycin resistance and high β-glucuronidase activity under the control of the C. utilis promoter. This finding can be explained by the presence of a prokaryotic core in the yeast promoter, predicted by in silico analysis of the sequence. This is the first report about functionality of a yeast promoter in A. tumefaciens.  相似文献   
78.
The family Prochilodontidae is considered a group with well conserved chromosomes characterized by their number, morphology and banding patterns. Thence, our study aimed at accomplishing a cytogenetic analysis with conventional methods (Giemsa staining, silver staining of the nucleolus organizer regions-AgNOR, and C-banding) and fluorescence in situ hybridization (FISH) with 18S and 5S ribosomal DNA probes in five species of the Prochilodus genus (Prochilodus argenteus, Prochilodus brevis, Prochilodus costatus, Prochilodus lineatus and Prochilodus nigricans) collected from different Brazilian hydrographic basins. The results revealed conservatism in chromosome number, morphology, AgNORs 18S and 5S rDNAs location and constitutive heterochromatin distribution patterns. The minor differences observed in this work, such as an Ag-NOR on a P. argenteus chromosome and a distinct C-banding pattern in P. lineatus, are not sufficient to question the conservatism described for this group. Future work using repetitive DNA sequences as probes for FISH will be interesting to further test the cytogenetic conservatism in Prochilodus.  相似文献   
79.
Ribosome-inactivating proteins (RIPs) are enzymes that inhibit protein synthesis after depurination of a specific adenine in rRNA. The RIP family members are classified as type I RIPs that contain an RNA-N-glycosidase domain and type II RIPs that contain a lectin domain (B chain) in addition to the glycosidase domain (A chain). In this work, we identified 30 new plant RIPs and characterized 18 Ricinus communis RIPs. Phylogenetic and functional divergence analyses indicated that the emergence of type I and II RIPs probably occurred before the monocot/eudicot split. We also report the expression profiles of 18 castor bean genes, including those for ricin and agglutinin, in five seed stages as assessed by quantitative PCR. Ricin and agglutinin were the most expressed RIPs in developing seeds although eight other RIPs were also expressed. All of the RIP genes were most highly expressed in the stages in which the endosperm was fully expanded. Although the reason for the large expansion of RIP genes in castor beans remains to be established, the differential expression patterns of the type I and type II members reinforce the existence of biological functions other than defense against predators and herbivory.  相似文献   
80.
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