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排序方式: 共有9178条查询结果,搜索用时 234 毫秒
91.
SUMIDA T.; SAKAMAKI T.; YONAHA F.; MAEDA T.; NAMEKAWA T.; NAWATA Y.; TAKABAYASHI K.; IWAMOTO I.; YOSHIDA S. 《Rheumatology (Oxford, England)》1994,33(5):420-424
To identify genetic factors that play a role in the pathogenesisof patients with SS over-representing Vß2 and Vß13genes in the lips, HLA-DR and -DQ alleles of 10 primary SS patientswith predominant expression of Vß2 and Vß13genes in the lips were analysed, using the polymerase chainreaction (PCR) and sequence specific oligonucleotide probes.The CDR3 amino acid sequences of cDNA clones encoding Vß2and Vß3 genes were also determined by PCR. The resultsshowed that the DRB4*0101 allele was significantly increased(80%) and that the frequency of DRB3 allele was decreased (0%)when compared to findings in healthy subjects (35.6 and 26%,respectively). Sequencing analyses demonstrated that 75% ofVß2 cDNA clones and 87% of Vß13 cDNA cloneshad a glutamine residue at position 106, in the CDR13 region.Moreover, the conserved sequences (Y*TLRNEQ) in the CDR3 ofVß13-positive T cell were detected in two differentclones (27%) from the two individual SS patients. These findingssuggest that the decreased DRB3 and increased DRB4*0101 allelesmay be associated with the antigens recognized by Vß2-and Vß13-positive T cells. KEY WORDS: HLA, Sjögren's syndrome, TCR Vß, CDR3 region 相似文献
92.
The anti-proliferative effect of proliferating cell nuclear antigen-specific antisense oligonucleotides on human gastric cancer cell lines 总被引:4,自引:0,他引:4
Chouhei Sakakura Akeo Hagiwara Hiroyuki Tsujimoto Kimihiko Ozaki Tsuguo Sakakibara Takayuki Oyama Masaharu Ogaki Toshio Takahashi 《Surgery today》1995,25(2):184-186
The proliferating cell nuclear antigen (PCNA) is a nuclear protein that leads DNA synthesis by the DNA polymerase delta. As the PCNA gene is strongly expressed in invasive gastric cancer cells with high proliferative activity, PCNA is suspected of playing an important role in the proliferation and advancement of gastric cancer. Thus, the effects of antisense oligonucleotides specific for PCNA mRNA were examined in seven gastric cancer cell lines. It was found that treatment with antisense oligonucleotides at concentrations of 10–40 M dose-dependently inhibited the growth of all cell lines; however, random sequence oligonucleotides did not modify the proliferation of any type of cells. These results indicate that PCNA is essential for cell proliferation in gastric cancer cells, and that the growth inhibitory effect results from the inhibition of PCNA gene expression. Therefore, PCNA-specific antisense oligonucleotides may be effective in the treatment of gastric cancer. 相似文献
93.
Two children with intractable fecal incontinence after correction of high anorectal malformations were successfully managed by the daily administration of a glycerin enema into the cecum via an appendicocecostomy or tubularized cecostomy, according to the method of Malone's antegrade continence enema (ACE). Fluoroscopic defecography performed during this procedure in each patient disclosed that the glycerin enema promptly evoked cecal peristalsis, which was transmitted to the distal colon and rectum, and squeezed out almost all the fecal matter, evacuating it from the anus. However, two enemas within a short interval were required to achieve a complete washout of feces. Although this report describes only two patients, our experience confirmed that the ACE was very effective and that adding the word continence to antegrade enema was justifiable. Moreover, fluoroscopic defecography was proven to play a significant role in determining the appropriate regimens of this technique to achieve complete washout of the feces. 相似文献
94.
Summary Substance P injected into the lumbar subarachnoid space of rats depressed the tail-flick response to radiant heat in a dose-dependent way. The effective doses ranged from 0.1 g to 100 g per rat (ED 50: 1.5 g/rat). The maximum of the effect was reached 20 min after intrathecal injection and the effect lasted for about 30 min. An antinociceptive effect was also observed after intrathecal injection of substance P 1 g to spinal rats. The depression of the tail-flick response produced by intrathecal administration of substance P was abolished by intrathecal (5 g/rat) or i.p. (0.5 mg/kg) injections of naloxone.Supported by the Sonderforschungsbereich 38 Membranforschung 相似文献
95.
James A. Fyfe Lilia M. Beauchamp Anthony O. Caggiano Raymond D. Price Takayuki Yamaji Nobuya Matsuoka Thomas A. Krenitsky 《Drug development research》2004,62(1):49-59
The ability of endogenous neurotrophins, including nerve growth factor (NGF), to promote the survival and development of neurons provides convincing evidence for their therapeutic potential, despite significant barriers to their successful clinical use. Many of these barriers might be surmountable, however, by strategies that enhance endogenous neurotrophin signaling. We evaluated a series of substituted pyrimidines for their ability to enhance the effects of NGF. KP544 [2‐amino‐5‐(4‐chlorophenylethynyl)‐4‐(4‐trans‐hydroxycyclohexylamino) pyrimidine] amplified NGF‐induced neurite outgrowth of PC12 cells approximately 2‐fold at 2 µM. KP544 also enhanced choline acetyltransferase activity, a marker of differentiation induced by either NGF or by cyclic AMP, by 3‐ to 8‐fold, with a 2‐fold amplification at 0.12–0.3 µM. This amplification occurred at all concentrations of NGF used including those that maximally stimulated the cells. KP544 did not increase the levels of phosphorylated mitogen‐activated protein kinases (MAPK) above that seen with NGF alone. These studies suggested that KP544 functions within the cell at a site that is downstream from or independent of MAPK signaling. NGF‐induced neurite outgrowth in a human cell line (SH‐SY5Y neuroblastoma cells) was also enhanced with KP544 treatment. Primary embryonic rat cortical cultures were used to extend the observations beyond the studies with the immortalized cell lines. In addition to effects on neurite outgrowth, KP544 protected these cells from glutamate‐induced death. Overall, the data suggest that KP544 can selectively interact in the differentiation pathway downstream of MAPK in a manner that amplifies nerve growth factor and cyclic AMP effects and is also neuroprotective. Drug Dev. Res. 62:49–59, 2004. © 2004 Wiley‐Liss, Inc. 相似文献
96.
Hideo Yamane Takayuki Nakagawa Hiroyoshi Iguchi Shigetarou Shibata Masahiro Takayama Kishiko Sunami Yoshiaki Nakai 《Auris, nasus, larynx》1997,24(3):221-225
We performed an in vitro study in order to determine possible triggers of hair cell regeneration in the chick basilar papilla following degeneration. We compared the response of sensory epithelium damaged by collagenase treatment with that damaged by acoustic trauma. The former exhibited no proliferative activity, but the latter did. The basilar papillae damaged by acoustic trauma could have proliferating activity in medium containing fetal bovine serum (FBS) or epidermal growth factor (EGF) but not in the medium without FBS or EGF. These findings indicate that regeneration of basilar papillae depends on the manner of cell death and that FBS or EGF is required for regeneration. 相似文献
97.
98.
Absence of p53 Overexpression and Favorable Response to Cisplatin-based Neoadjuvant Chemotherapy in Urothelial Carcinomas 总被引:3,自引:0,他引:3
Yoshiyuki Kakehi Enver Özdemir Tomonori Habuchi Hirohiko Yamabe Takayuki Hashimura Yoshitaka Katsura Osamu Yoshida 《Cancer science》1998,89(2):214-220
It has been controversial whether cancer cells harboring loss or inactivation of the tumor suppressor p53 are resistant or sensitive to DNA-damaging agents including cisplatin and doxorubicin. Overexpression of mdm2 oncoprotein, a negative regulator of p53, is assumed to be an alternative to p53 dysfunction. Archival urothelial carcinoma specimens obtained from 60 patients prior to cisplatin-based chemotherapy were immunohistochemically studied for overexpression of p53 and mdm2. Thirty-two patients (group I) were treated with chemotherapy in the neoadjuvant setting, while 28 patients (group II) underwent chemotherapy for distant metastases or inoperable locoregional tumors. In group I, the responsiveness was correlated with staining status of p53 ( P =0.0225) and the combination of p53 and mdm2 ( P =0.0497). Negative staining of p53 and negative for both p53 and mdm2 could have predicted favorable response to chemotherapy in 16 of 18 (88.9%) and in 12 of 13 (92.3%) tumors, respectively. On the other hand, p53-positive and p53 and/or mdm2-positive staining could have predicted poor response only in 7 of 14 (50.0%) and 8 of 19 (42.1%) tumors, respectively. Disease-specific survival of the p53-negative group was significantly superior to that of the p53-positive group ( P =0.0086). Difference in survival did not become more significant when overexpression of mdm2 was taken into consideration ( P =0.0456). In contrast, in group II, there was no correlation of responsiveness to chemotherapy or survival with p53- or p53/mdm2-staining status. The patients with urothelial carcinomas negative for overexpression of p53 will benefit from neoadjuvant chemotherapy. From clinical viewpoint, however, p53 status alone or the combination of p53 and mdm2 status is not enough to identify those patients who will not benefit from the treatment. 相似文献
99.
100.