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81.
胃、结直肠癌术前区域性动脉化疗几个相关问题   总被引:2,自引:0,他引:2  
胃、结直肠癌根治性切除术复发转移是严重影响术后5 a生存率提高的重要原因.以手术为主综合治疗已成为新的趋势,其中术前区域性动脉化疗(preoperative regional-arterial chemotherapy,PRAC)尤为值得重视.本文介绍了术前PRAC的概念、作用机制和影响区域性动脉化疗疗效的相关因素,并就术前区域性动脉化疗在胃、结直肠癌综合治疗中的评价进行讨论.  相似文献   
82.
Much of bladder cancer in East Africa and the Middle East isattributed to chronic urinary infection with Schistosoma haematobium(‘schistosomiasis’). Most schistosomal bladder cancer(SBC) is squamous cell carcinoma (SCC) and occurs in the fifthdecade of life. In contrast, nonschistosomal bladder cancer(NSBC) in Western countries usually occurs in the seventh decadeof life and is largely transitional cell carcinoma (TCC). Toshed light on the mechanisms underlying these different patternsof bladder cancer we looked for mutations in the p53 gene inSBC from 92 patients in Egypt, where schistosomiasis is hyperendemic.Patients' mean age at presentation of bladder cancer was 49.4± 9.9 years and 90% had a clinical history of schistclsomiasisand/or histological evidence of schistosomal eggs adjacent tothe carcinoma. There were 53 SCC, 23 TCC, 13 adenocarcinomasand three other carcinomas. Thirty patients had tumours withmutations in exons 5–8 of the p53 gene: 17/53 SCC, 8/23TCC, 4/13 adenocarcinomas and 1/3 other tumours. Of 19 mutationsin SCC, 16 were base pair substitutions (BPS), two were deletionsand one an insertion. Two tumours each contained two mutations.Of the BPS, nine were transitions at CpG dinucleotides and twowere G  相似文献   
83.
In vitro fertilization and embryo transfer: two-year experience   总被引:1,自引:0,他引:1  
Between February 1983 and January 1985, 206 laparoscopies were performed on 172 women following controlled ovarian hyperstimulation with human menopausal gonadotropin (hMG) and human chorionic gonadotropin (hCG). Sixty-four clinical pregnancies advanced beyond the sixth week of gestation and were confirmed by ultrasound; and 37.2% of the patients conceived after in vitro fertilization and embryo transfer. The clinical pregnancy rate was 31.1% when based on the number of laparoscopies performed and 33.9% when based on the number of embryo transfers. There were 12 multiple pregnancies (18.8%), 11 miscarriages (17.2%), and one ectopic (tubal) pregnancy (1.6%). The most important factors contributing toward the success of this program were the establishment of specific criteria for patient selection, rigid adherence to clinical and laboratory protocols, and the maintenance of strict quality control.  相似文献   
84.
Most of the current in vitro fertilization and embryo transfer (IVF-ET) programs are university-based. The establishment of a successful ambulatory IVF program in association with a busy, two-man general obstetrics-gynecologic practice is described. Seventy-one infertile couples were screened between February 1 and October 15, 1983. Forty-three couples were judged eligible for IVF-ET. Forty-three women underwent a single attempt at ET. The first 13 of these women underwent controlled ovarian hyperstimulation (COH) with 150 mg clomiphene citrate and human chorionic gonadotropin (hCG), and the remaining 30 underwent COH with human menopausal gonadotropin (hMG) and hCG. One of the 13 patients who underwent COH with clomiphene citrate conceived but subsequently miscarried early in the first trimester, for an 8% pregnancy rate. There were 12 pregnancies among the 30 patients who received hMG and hCG, for a 40% pregnancy rate. Only three of these pregnancies miscarried in the early first trimester, and three of the nine viable pregnancies are twin gestations. The possible factors responsible for the high pregnancy rate with IVF-ET, using COH with hMG and hCG, are discussed, and the feasibility of its performance in a well-controlled, non-university program is demonstrated.  相似文献   
85.
BACKGROUND: We have shown previously that interleukin (IL) -1 beta- and IL-6-induced promatrilysin expression is mediated by an indirect pathway that requires NF kappa B-dependent synthesis of IL-6 and STAT3 signaling. We now demonstrate that IL-1 beta-induced but not IL-6-induced promatrilysin expression can be blocked by androgens in the prostate carcinoma cell line LNCaP (lymph node-derived carcinoma cells of the prostate). METHODS: By using enzyme-linked immunosorbent assay analyses, promatrilysin was measured in LNCaP cells stimulated with IL-1 beta or IL-6 LNCaP-treated cells pretreated with testosterone. In addition, promatrilysin message was measured by using Northern analyses after IL-6-treated cells pretreated with testosterone. RESULTS: In LNCaP treated with testosterone before IL-1 beta stimulation induced promatrilysin expression was completely abrogated. Furthermore, testosterone completely abrogated NF kappa B transactivation activity and induction of IL-6 protein expression and mRNA. Testosterone and 5 alpha-dihydrotestosterone did not have an inhibitory effect on IL-6-induced promatrilysin expression. Testosterone also had no effect on basal promatrilysin expression or basal NF kappa B transactivation activity. CONCLUSION: From these data, we conclude that testosterone blocks IL-1 beta-induced promatrilysin expression by inhibition of NF kappa B transactivation activity, which in turn, blocks IL-6 expression. These data suggest a mechanism in vivo by which invasive and metastatic prostatic carcinoma cell clones refractory to hormone ablation therapy may develop after chemical or surgical castration. Furthermore, these data suggest that, perhaps, upstream targets such as the cytokines IL-1 beta and IL-6 may provide alternative drug targets for inhibiting prostate cancer progression.  相似文献   
86.
The novel putative anticonvulsant drug 1-[2,6-difluorophenyl)-methyl]-1H-1,2,3-triazolo[4,5-c]) pyridine-4-amine monohydrochloride (BW534U87) effectively reduced seizures induced in rodents by threshold maximal and supramaximal electroshock, electrical kindling, pentylenetetrazole (PTZ) infusion and by vestibular stimulation in the genetically seizure-prone epilepsy-like (EL) mouse. The range of animal seizure models in which BW534U87 was effective is consistent with a broad spectrum anticonvulsant profile. In the EL mouse, the activity of BW534U87 was partially reversed by predosing with the selective adenosine A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX), suggesting that an adenosine-dependent mechanism contributed to the antiseizure activity of the drug. BW534U87 inhibited rat brain homogenate adenosine deaminase activity, thus, raising the possibility that, by blocking the metabolism of endogenous adenosine by this route, BW534U87 limited seizure activity by promoting the inhibitory tone mediated by endogenous adenosine in the brain. The seizure protection conferred by the selective adenosine deaminase inhibitor erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA) in EL mice and mice infused with PTZ confirms that inhibition of adenosine metabolism by deamination is an effective antiseizure strategy in these models.  相似文献   
87.
A potentially contributing factor to the development and chronicity of pyoderma gangrenosum is infection with the relatively recently characterized human pathogen, Chlamydia pneumoniae. C pneumoniae is an obligate intracellular bacterium that can infect endothelial, monocyte, and smooth muscle cells and is associated with cardiopulmonary diseases. A case of serologically, polymerase chain reaction-positive, immunohistochemically, and culture-documented viable C pneumoniae organisms in a chronic pyoderma gangrenosum ulcer is reported, a finding that has not been described previously.  相似文献   
88.
BRAF and RAS mutations in human lung cancer and melanoma   总被引:22,自引:0,他引:22  
BRAF encodes a RAS-regulated kinase that mediates cell growth and malignant transformation kinase pathway activation. Recently, we have identified activating BRAF mutations in 66% of melanomas and a smaller percentage of many other human cancers. To determine whether BRAF mutations account for the MAP kinase pathway activation common in non-small cell lung carcinomas (NSCLCs) and to extend the initial findings in melanoma, we screened DNA from 179 NSCLCs and 35 melanomas for BRAF mutations (exons 11 and 15). We identified BRAF mutations in 5 NSCLCs (3%; one V599 and four non-V599) and 22 melanomas (63%; 21 V599 and 1 non-V599). Three BRAF mutations identified in this study are novel, altering residues important in AKT-mediated BRAF phosphorylation and suggesting that disruption of AKT-induced BRAF inhibition can play a role in malignant transformation. To our knowledge, this is the first report of mutations documenting this interaction in human cancers. Although >90% of BRAF mutations in melanoma involve codon 599 (57 of 60), 8 of 9 BRAF mutations reported to date in NSCLC are non-V599 (89%; P < 10(-7)), strongly suggesting that BRAF mutations in NSCLC are qualitatively different from those in melanoma; thus, there may be therapeutic differences between lung cancer and melanoma in response to RAF inhibitors. Although uncommon, BRAF mutations in human lung cancers may identify a subset of tumors sensitive to targeted therapy.  相似文献   
89.
Proximal interphalangeal joint arthroplasties were performed on 40 toes of 10 fresh-frozen cadaveric feet. Twenty toes had a transverse elliptical incision of skin and extensor mechanism, and 20 had a longitudinal incision with transverse excision of extensor mechanism. Venous anatomy, including damage to the dorsal collateral veins, was noted. In the transverse-incision group, 14 (70%) of 20 toes had 1 dorsal vein transected, and 2 (10%) of 20 toes had both dorsal veins transected; in the longitudinal-incision group, no dorsal collateral veins were injured. As transverse incisions carry a high risk for damaging the dorsal collateral veins, and such damage may contribute to postoperative swelling, care should be taken to protect these veins. Longitudinal incisions are less likely to damage these venous structures.  相似文献   
90.
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