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131.
M Sasaki  Y Kaneko 《Hinyokika kiyo. Acta urologica Japonica》1990,36(8):909-12; discussion 912-3
To obtain objective information about bladder cancer, we measured the mean nuclear volume of bladder cancer cells by using the "Point Sampled Intercepts" method, which was published by Gundersen et al. Thirty one cases of bladder cancer were selected and divided into 2 groups: group A; no recurrence over 3 years after initial TUR (12 cases), group B; cystectomy or cancer death (19 cases). Estimated mean nuclear volume was significantly smaller in group A than in group B. It is suggested that estimation of the mean nuclear volume by this stereological method may provide objective information for predicting the prognosis of patients with bladder cancers. Further studies in additional patients are required to substantiate the predictive potential of this method.  相似文献   
132.
Nucleos(t)ide analogs (NAs) cannot completely suppress the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB). This study aimed to identify the risk factors for HCC development in naïve CHB patients treated with current NA. Patients receiving NA (n = 905) were recruited retrospectively from the 17 hospitals of the Japanese Red Cross Liver Study Group. All treatment-naïve patients had been receiving current NA continuously for more than 1 year until the end of the follow-up. We analyzed the accuracy of predictive risk score using the area under receiver operating characteristic curve. The albumin–bilirubin (ALBI) score was significantly improved by NA therapy (−0.171 ± 0.396; p < 0.001 at Week 48). A total of 72 (8.0%) patients developed HCC over a median follow-up of 6.2 (1.03–15.7) years. An independent predictive factor of HCC development was older age, cirrhosis, lower platelet counts at baseline and ALBI score, and alpha-fetoprotein (AFP) at 1 year after NA therapy according to multivariate analysis. The accuracy was assessed using the PAGE-B, mPAGE-B, aMAP, APA-B, and REAL-B scores that included these factors. Discrimination was generally acceptable for these models. aMAP and REAL-B demonstrated high discrimination with 0.866/0.862 and 0.833/0.859 for 3- and 5-year prediction from the status of 1 year after NA therapy, respectively. Baseline age and platelet count, as well as ALBI and AFP one year after NA, were useful for stratifying carcinogenesis risk. The aMAP and REAL-B scores were validated with high accuracy in Japanese CHB patients.  相似文献   
133.
Cultivated T24 cells derived from a human bladder cancer were inoculated into the chorioallantoic membrane vein of chick embryos. Hyperthermic treatment was performed following injection of anticancer agents 3 days after the inoculation of the T24 cells. DNA samples were obtained from the livers of the chick embryos, and the polymerase chain reaction technique was used to amplify a DNA fragment specific to the human -globin gene. The Southern hybridization method was used to evaluate the inhibitory effects of anticancer agents in combination with/without hyperthermia on T24 cells metastasized to the liver. The hyperthermia exerted an inhibitory effect on the growth of the T24 cells in the livers of the chick embryos, and this was dependent on the thermal dose. The antitumor effects of hyperthermia performed at 42.5° C for 20 min and at 43.0° C for 10 min were evidenced by 69.2% an 82.0% inhibition of the growth of the metastasized T24 cells, respectively, as compared with the growth of untreated T24 cell. Hyperthermia performed at 42.5° C for 10 min alone produced 26.7% tumor growth inhibition, and these conditions for hyperthermia were subsequently used as a criterion for evaluating the effects of its combination with various anticancer agents. Adriamycin (20 g/egg) alone, mitomycin C (10 g/egg) alone, carboplatin (10 g/egg) alone, and cisplatin (10 g/egg) alone produced 13.5%, 58.9%, 27.3%, and 29.1% tumor growth inhibition, respectively. Adriamycin and mitomycin C applied in combination with hyperthermia showed additive inhibitory effects on the growth of the metastasized T24 cells in this chick embryo model.  相似文献   
134.
Mammary tumors of a newly isolated strain of Chinese wild mouse (JYG mouse) harbor exogenous mouse mammary tumor virus (MMTV). The complete nucleotide sequence of exogenous JYG-MMTV was determined on the proviral 5' long terminal repeat (LTR)(partial)-gag-pol-env-3' LTR (partial) fragment cloned into a plasmid vector and the cDNA sequence from JYG-MMTV producing cells. Similarly to the other MMTV species the LTR of JYG-MMTV contains an open reading frame (ORF). The amino acid sequence of the JYG-MMTV ORF resembles that of SW-MMTV (92% identity) and endogenous Mtv-7 (93% identity) especially at the C-terminal region. Thus, a functional similarity in T-cell receptor V beta recognition as a superantigen is implicated among these MMTV species. Analysis of the viral gag nucleotide sequence revealed that this gene is not disrupted by the bacterial insertion sequence IS1 or IS2, which have been reported to be present in the majority of the plasmids containing the gag region. Comparison of amino acid sequences of JYG-MMTV with those of BR6-MMTV showed that over 96% of the amino acids of gag, pol, protease and env products are identical. These results suggest the intact nature of the nucleotide sequence of the near full-length MMTV genome cloned in the plasmid.  相似文献   
135.
BACKGROUND: The present study examined the relation between fish consumption and mortality from all causes, ischemic heart disease, and stroke. METHODS: The fish consumption data in 1961-1963, 1979-1981, and 1989-1991 and mortality data, age-standardized to 45-74 years, mean of the latest available 3 years, mostly around 1992-1993, in 36 countries, were obtained from the Food and Agriculture Organization and the World Health Organization, respectively. RESULTS: There exists an inverse univariate correlation between log fish consumption in 1961-1963, 1979-1981, and 1989-1991 and log all-cause (P < 0.01 to < 0.001) and ischemic heart disease (P < 0.05 to < 0.01) mortality in both sexes. An inverse univariate correlation between log fish consumption and log stroke mortality was found only for the period 1961-1963 in both sexes (P < 0.05). Log fish consumption was independently, significantly, and inversely associated with log all-cause (all P < 0.001), ischemic heart disease (P < 0.01 to < 0.001), and stroke (P < 0.05 to < 0.001) mortality in all three time periods in both sexes, after adjusting for confounding factors. These associations remained significant even after exclusion of Iceland and Japan, countries with the highest amount of fish consumption and the lowest all-cause mortality rate. CONCLUSIONS: Fish consumption is associated with a reduced risk from all-cause, ischemic heart disease, and stroke mortality at the population level.  相似文献   
136.
We synthesized 18F-FDG by using an automated synthetic apparatus "FDG MicroLab" (GE Medical Systems) which produces 18F-FDG by a solid phase 18F-fluorination. Its quality and reproducibility were evaluated in order to assess feasibility of the apparatus for routine clinical production of 18F-FDG. For 5 consecutive 18F-FDG synthesis, target irradiation was carried out at 15 microA for 60 min. 18F-FDG was obtained in 50 min after EOB with an end-of-synthesis yield of 9.34 +/- 1.06 GBq. Radiochemical yield and radiochemical purity were 47 +/- 3% (decay corrected) and 98.0 +/- 0.5%, respectively. Other several quality control parameters tested conformed with "Standards of Compounds Labeled with Positron Nuclides" (RADIOISOTOPES, 44, 1995). Thus, the automated synthetic apparatus "FDG MicroLab" has proven to stably produce 18F-FDG with high yield and high purity. The apparatus is feasible for routine clinical production of 18F-FDG.  相似文献   
137.
The purpose of this study was to analyze the results of initial radiotherapy for bone metastases (BM) from breast cancer and to investigate the prognostic factors. Between 1981 and 1995, 65 women (109 lesions) received initial radiotherapy for BM, aiming at a total dose of 50 Gy/25 Fr. Significant relief of pain was obtained in 61 (88.4%) of 69 estimable lesions according to the RTOG score. The control rates of pain including the prevention of pathological fractures or myelopathy were 80.4% at 5 years and 64.3% at 10 years. The median survival time of all patients was 11 months, and the survival rates were 56% at 1 year, 31.6% at 3 years, 17.9% at 5 years and 10.7% at 10 years, with five long-term survivors. Univariate analysis showed that a normal state of LDH, no other metastatic organs, a disease-free interval longer than two years, good performance status (0 or 1), BM limited to the axial bones, maintenance chemo-hormonal therapy and an age of more than 55 years were good prognostic factors. Multivariate analysis showed that LDH, age and performance status were significant predictors of prognosis. It is important to note the prognostic factors at the initial treatment of BM from breast cancer. We consider that further prospective studies are needed to determine the optimal treatment schedule, including radiotherapy and its combination with chemohormonal therapy, for BM.  相似文献   
138.
OBJECTIVES: To establish the source of metallic artifacts on postoperative MRI of the temporomandibular joint after arthroplasty. METHODS: An experiment was carried out to evaluate MR artifacts which were thought to have been caused by minute metallic particles deposited at surgery. Four types of cutting instruments were used to cut an extracted tooth: a diamond bur attached to a dental air turbine handpiece, a steel bur and bone bur attached to a dental micromotor handpiece and a bone file. The tooth fragments were collected in plastic centrifuge tubes in water. These samples were evaluated with six MR sequences. RESULTS: MR artifacts were clearly demonstrated in samples using the bone bur and the bone file but not the diamond and steel burs. CONCLUSIONS: The artifacts seen on postoperative MRI were derived from minute metal particles from the bone bur or file used for condylar arthroplasty. Metal artifacts should be considered when interpreting postoperative MR images.  相似文献   
139.
The clinical outcome of 122 patients with pituitary adenomas treated by microsurgery and/or Gamma Knife radiosurgery (GKRS) was analyzed to evaluate patient selection criteria and the role of GKRS. Sixty-six resections were performed in 59 patients. All tumors were macroadenomas, except for 5 ACTH-producing adenomas. Twenty-four of the 31 hypersecreting adenomas showed normal serum hormone values after treatment. Postoperative complications were rhinorrhea, cranial nerve palsies, and a small thalamic infarct. GKRS was performed on 18 of the operated patients because of residual tumors, mostly in the cavernous sinus. Thirty-five of the 63 patients treated by GKRS were followed for more than 2 years. All adenomas except 2 were stable or had decreased in size. Eleven of 17 functioning adenomas showed normal serum hormone values after treatment. It is concluded that tumors that compress the optic pathway should be removed and that residual tumors in the cavernous sinus are good indications for radiosurgery.  相似文献   
140.
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