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91.
目的了解ret/PTC基因突变与超声、病理诊断在甲状腺乳头状癌诊断中的关系。方法术前超声检查,并在超声引导下细针穿刺,活体取材进行病理诊断和逆转录聚合酶链(RT-PCR)方法检测ret/PTC基因突变。结果在34例超声与病理诊断的甲状腺乳头状癌(PTC)患者中,16例分子生物学检测发现ret/PTC基因突变(47%),其中8例为PTC-1基因突变(50%),2例PTC-2基因突变(12.5%),2例PCT-3基因突变(12.5%),3例PTC-1和PTC-2突变同时存在(18.75%),1例PTC-1和PTC-3突变同时存在(6.25%)。结论ret/PTC基因重组突变可存在于散发的甲状腺乳头状癌中,主要表现PTC-1型。应用超声引导下细针穿刺与甲状腺乳头状癌基因突变的检测相结合是早期诊断甲状腺乳头状癌的有效方法。 相似文献
92.
The mechanism of action of systemitically administered(±)-MDMA (3, 4-methylenedioxymethamphetamine) on spontaneously active neurons in the medial prefrontal cortex (mPFc) of chloral hydrate anesthetized rats was examined using standard single unit extracellular recording techniques. Intravenously administered MDMA dose-dependently decreased the firing rates of the majority of mPFc neurons in control rats. In contrast, in rats that were pretreated withp-chlorophenylalanine (PCPA), which depletes the brain serotonin (5-hydroxytryptamine, 5-HT) content by inhibiting tryptophan hydroxylase, the rate-limiting enzyme in the synthesis of 5-HT, MDMA was largely ineffective in inhibiting the firing of mPFc cells. In PCPA-treated animals, the administration of 5-hydroxytryptophan (5-HTP), which presumably restored the brain 5-HT content, but notl-DOPA, reinstated MDMA's inhibitory action in PCPA-treated rats. In rats that were pretreated withα-methyl-p-tyrosine (AMPT), which depletes the brain dopamine (DA) content by inhibiting tyrosine hydroxylase, the rate-limiting enzyme in the synthesis of DA, MDMA inhibited the firing of all of the mPFc cells. MDMA's effect on mPFc neurons was reversed by 5-HT receptor antagonists such as granisetron and metergoline. These results strongly suggest that MDMA exerts its action on mPFc cells indirectly by releasing endogenous 5-HT. 相似文献
93.
Hideaki Iwaki Kazuyoshi Johnin Susumu Kageyama Chul Jang Kim Takahiro Isono Tatsuhiro Yoshiki 《International journal of urology》2007,14(10):918-923
OBJECTIVES: Vesicoureteral reflux (VUR) is the most common congenital urinary tract anomaly. This disease can pose a major threat to the kidneys as twenty percent of patients with endstage renal disease are reported to have VUR. Although genetic studies for uroplakin III (UPIII) have been reported recently, no study has focused on UPIII gene expression in VUR patients. We describe here the up-regulation of UPIII mRNA in exfoliated urinary cells from primary VUR patients. METHODS: A real-time RT-PCR for UPIII mRNA was performed on exfoliated urothelial cells from 18 primary VUR and 38 control samples. UPIII mRNA copies were calculated for each sample. The statistical differences were assessed by the Mann-Whitney U test. Receiver operator characteristic curves were constructed for analysis of the diagnostic values. RESULTS: UPIII mRNA was found to be up-regulated to a greater extent in VUR than in control exfoliated urinary cells (mean +/- SE: 497.0 +/- 178.5 copies vs. 69.0 +/- 10.0 copies, respectively, P < 0.001). In evaluating the measurement of urinary UPIII mRNA as a screening test for VUR, the sensitivity was 77.8% and the specificity was 76.3% by the best diagnostic cutoff point. CONCLUSIONS: This is the first report demonstrating up-regulation of UPIII in mRNA levels in VUR patients. We submit that the quantitative measurement of urinary UPIII mRNA has a potential of developing into the first non-invasive screening test for VUR. 相似文献
94.
Tae-Jin Song M.D. Ph.D. David P. Eisenberg M.D. Prasad S. Adusumilli M.D. Michael Hezel B.S. Yuman Fong M.D. 《Journal of gastrointestinal surgery》2006,10(4):532-542
The rising incidence of hepatocellular carcinoma (HCC) in western countries, along with the poor prognosis offered by present-day
treatment modalities, makes novel therapies for this disease necessary. Oncolytic herpes simplex viruses (HSV) are replication-competent
viruses that are highly effective in the treatment of a wide variety of experimental models of human malignancies. This study
seeks to investigate the effectiveness of oncolytic herpes viruses in the treatment of primary HCC cell lines. Sixteen commercially
available human HCC cell lines were studied. G207 is an attenuated, replication-competent, oncolytic HSV engineered to selectively
replicate within cancer cells. Cell lines were tested for viral sensitivity to G207 and their ability to support viral replication
using standard cytotoxicity and viral replication assays. Eleven of 16 cell lines were moderately to highly sensitive to G207
viral oncolysis. HCC cell lines additionally demonstrated the ability to support viral replication in vitro with as high as
800-fold amplification of the administered viral dose observed. G207 is cytotoxic to, and efficiently replicates within, HCC
cell lines in vitro. From these data, we suggest that oncolytic HSV therapy may have a role in the treatment of HCC, and in
vivo studies are warranted.
Presented in part at the 2005 American Hepato-Pancreato-Biliary Association Congress, Hollywood, Florida, April 14–17, 2005.
Supported by grants R01CA75461 and R01CA72632 from the National Institutes of Health, and by grant MBC-99366 from the American
Cancer Society (Yuman Fong). 相似文献
95.
TONG Saixiong PANG jinzhong SUO Tao JIN Haiying 《美国中华健康卫生杂志》2005,8(4):41-44
Objective To evaluate preliminarily the effect of HSV - tk/GCV system on gallhladder carcinoma cells in vitro.Methods Recombinant retroviral vector PLtkSN containing tk suicide gene was transfacted into gallbladder carcinoma cells, mediated by LipofectAMINETM 2000 liposome, and the growth - inhibiting rotes of GBC, SD/tk cells in the different GCV concentrations were measured by MTr methods; GBC - SD cells were mixed in the different proportions, and death rotes of the mixed cells treated with GCV were detected to verify by stander effect. Resuts GCV could lead GBC - SD/tk cells to significant death, and there was striking difference compared with the control cells (p〈0.01). When the concentration of GCV was 1,10, 50,100,500ug/ml, the killing rate of GBC - SD/tk cells was respecfively 6.8%, 2.5.2%, 54.5%, 66.3%, 89.3%, indicating dose - dependent phenomenon; With GBC - SD/tk cells in the proportion of 0, 10%, 20% ,50%, 70%, 100%, the killing rate of the mixed cells treated with GCV was 0, 19.7%, 40.3%, 77.7%, 88.0%, 93.5%, respectively. It was apparent that bystander effect was observed in the experiment. Condusion HSV - tk/GCV system could be a potential tool for the treatment of carcinoma. 相似文献
96.
目的探讨自发性高血压大鼠颈动脉中抑癌基因P53和原癌基因c-jun、c-fos、c-myc mRNA的表达.方法用逆转录聚合酶链式反应检测两种基因的表达水平.正常雄性大鼠作为对照组.结果 SHR颈动脉中,抑癌基因P53和原癌基因c-jun、c-fos、c-myc均有高表达,较WKY差异有显著性(P<0.05).结论自发性高血压大鼠颈动脉组织中抑癌基因P53和原癌基因c-jun、c-fos、c-myc均有高表达,癌基因的活化可能与自发性高血压大鼠颈动脉血管重构有关. 相似文献
97.
Yoshinori Itoh Yutaka Kohgo Naoki Watanabe Yuji Kanisawa Sumio Sakamaki Minoru Takahashi Yasuo Hirayama Hiroyuki Ono Takeshi Himeno Yoshiro Niitsu 《Cancer science》1991,82(11):1203-1206
Human tumor–infiltrating lymphocytes (TILs) derived from pleural or ascitic fluid were incubated with recombinant interleukin 2 and transfected with human tumor necrosis factor (TNF) a gene by the lipofection procedure. The resulting TILs secreted significant amounts of TNF in the culture supernatant and exhibited cytotoxicity against established cell lines, such as K562 and Daudi, and autologous tumor cells. The TNF gene–transfected TILs exhibited an augmented killing of autologous tumor cells. 相似文献
98.
99.
M. W. Oram D. I. Perrett J. K. Hietanen 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,97(2):274-294
An investigation was made into the directional sensitivity of cells in the macaque anterior superior temporal polysensory region (STPa) to the motion of objects. The cells studied were sensitive to the presence of motion but showed little or no selectivity for the form of the stimulus. Directional tuning was not continuously distributed about all possible directions. The majority of cells were most responsive to motion in a direction within 15° of one of the three cartesian axes (up/down, left/right, towards/away). Tuning to direction varied in sharpness. For most (34/37) cells the angular change in direction required to reduce response to half maximal was between 45 and 70° (for 3/37 cells it was > 90°). The estimates of the directionality (median I
d = 0.97) of STPa cells was similar to that reported for posterior motion processing areas (the middle temporal area, MT, and the medial superior temporal area, MST). The tuning for direction (sharpness, distribution and discrimination) of the motion-sensitive STPa cells were found to be similar to the tuning for perspective view of STPa cells selective for static form of the head and body. On average the STPa responses showed a 100- to 300-ms transient burst of activity followed by a tonic discharge maintained at approximately 20% of the peak firing rate for the duration of stimulation. The responses of motion-sensitive STPa cells occurred at an earlier latency (mean 91 ms) than responses of cells selective for static form (mean 119 ms), but the time course of responses of the two classes of cell were similar in many other respects. The early response latency and directional selectivity indicate that motion sensitivity in STPa cells derives from the dorsal visual pathway via MT/MST. The similarity of tuning for direction and perspective view within STPa may facilitate the integration of motion and form processing within this high-level brain area. 相似文献
100.
Gene delivery systems are designed to control the location of administered therapeutic genes within a patient's body. Successful in vivo gene transfer may require (i) the condensation of plasmid and its protection from nuclease degradation, (ii) cellular interaction and internalization of condensed plasmid, (iii) escape of plasmid from endosomes (if endocytosis is involved), and (iv) plasmid entry into cell nuclei. Expression plasmids encoding a therapeutic protein can be, for instance, complexed with cationic liposomes or micelles in order to achieve effective in vivo gene transfer. A thorough knowledge of pharmaceutics and drug delivery, bio-engineering, as well as cell and molecular biology is required to design optimal systems for gene therapy. This mini-review provides a critical discussion on cationic lipid-based gene delivery systems and their possible uses as pharmaceuticals. 相似文献