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21.
Aoi W Naito Y Sakuma K Kuchide M Tokuda H Maoka T Toyokuni S Oka S Yasuhara M Yoshikawa T 《Antioxidants & redox signaling》2003,5(1):139-144
Dietary antioxidants may attenuate oxidative damage from strenuous exercise in various tissues. Beneficial effects of the antioxidant astaxanthin have been demonstrated in vitro, but not yet in vivo. We investigated the effect of dietary supplementation with astaxanthin on oxidative damage induced by strenuous exercise in mouse gastrocnemius and heart. C57BL/6 mice (7 weeks old) were divided into groups: rested control, intense exercise, and exercise with astaxanthin supplementation. After 3 weeks of exercise acclimation, both exercise groups ran on a treadmill at 28 m/min until exhaustion. Exercise-increased 4-hydroxy-2-nonenal-modified protein and 8-hydroxy-2'-deoxyguanosine in gastrocnemius and heart were blunted in the astaxanthin group. Increases in plasma creatine kinase activity, and in myeloperoxidase activity in gastrocnemius and heart, also were lessened by astaxanthin. Astaxanthin showed accumulation in gastrocnemius and heart from the 3 week supplementation. Astaxanthin can attenuate exercise-induced damage in mouse skeletal muscle and heart, including an associated neutrophil infiltration that induces further damage. 相似文献
22.
Preemptive analgesia by zaltoprofen that inhibits bradykinin action and cyclooxygenase in a post-operative pain model 总被引:2,自引:0,他引:2
The post-operative pain state results from a barrage of primary afferent inputs exposed to products of tissue damage such as bradykinin and prostaglandins and the central sensitization by the continuing inputs. This provides the rationale for preemptive analgesia, whereby the blockade of primary afferent inputs prior to injury may result in a reduction of post-operative pain. 2-(10,11-dihydro-10-oxo-dibenzo[b,f]thiepin-2-yl) propionic acid (zaltoprofen) is a unique compound that inhibits cyclooxygenase (COX) and exhibits anti-bradykinin activity. The present study evaluated the preemptive analgesic effect of zaltoprofen in a post-operative pain model produced by plantar incision. When orally, but no intrathecally, administered 30 min prior to incision, zaltoprofen significantly increased the withdrawal threshold 2 h and 1-3 days after incision at 10 mg/kg. While the bradykinin B1 antagonist des-Arg10-HOE-140, the selective COX-1 inhibitor SC-560, and the selective COX-2 inhibitor celecoxib did not affect post-operative pain, the B2 antagonist HOE-140 dose-dependently relieved the post-operative pain at 2-200 microg/kg with a time course similar to that of zaltoprofen. The B2 receptor mRNA was expressed in the hindpaw and the expression did not change before and 24 h after surgery. These results suggest that zaltoprofen produces the preemptive analgesic effect peripherally by blocking the B2 pathway. 相似文献
23.
24.
Methyl-3,3,3-trifluoropropylsiloxane (F)-dimethylsiloxane (D) random and block copolymers were prepared. The random copolymers were prepared by equilibrium copolymerization starting from a mixture of cyclic F and D siloxanes with potassium silanolate as the catalyst. The F-D block copolymer was prepared by sequential anionic living polymerization of strained cyclic trisiloxanes using butyllithium as initiator, first polymerizing D3 then adding F3 after consumption of D3. The copolymer microstructure was established by means of 29Si NMR, differential scanning calorimetry (DSC), and gel-permeation chromatography (GPC). Characteristic glass transition temperature (Tg) shifts were observed depending on the F:D ratio of the random copolymers. It was demonstrated that the tensile strength of the poly(methyl-3,3,3-trifluoropropylsiloxane)-poly(dimethylsiloxane) (PTFPMS-PDMS) blend system was improved when either of the copolymers was added. 相似文献
25.
Ken Hayashi Hiroki Kuniyasu Naohide Oue Hideo Shigeishi Kazuya Kuraoka Hirofumi Nakayama Wataru Yasui 《Pathobiology》2002,70(1):40-46
DNA damage triggers the activation of checkpoints that delay cell cycle progression to allow for DNA repair. Loss of G2 checkpoints provides a growth advantage for tumor cells undergoing aberrant mitosis. However, the precise mechanisms of G2 checkpoints acting in gastric cancer are unknown. Here, we analyzed the G2 checkpoint function in two gastric cancer cells, MKN-28 cells containing a mutant p53 gene and MKN-45 cells which have wild-type p53. Two agents damaging DNA, camptothecin (CPT) or ultraviolet light (UV), were utilized to trigger a G2 phase cell cycle checkpoint response in these tumor cells. Both CPT and UV inhibited the growth of MKN-45 cells, whereas they did not affect the growth of MKN-28 cells. CPT induced cell cycle arrest at the G2/M phase and enhanced the expression of human RAD9 (hRAD9) in MKN-45 cells. In addition, hRAD9 showed perinuclear staining and similar localization with Bcl-2 in MKN-45 cells but not in MKN-28 cells after having applied CPT or UV light. These results suggest that besides p53 activity, the induction of hRAD9 is required for G2/M checkpoint signal transduction in gastric cancer cells. 相似文献
26.
Regulation of tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) and TRAIL receptor expression in human neutrophils 总被引:14,自引:0,他引:14 下载免费PDF全文
Kamohara H Matsuyama W Shimozato O Abe K Galligan C Hashimoto S Matsushima K Yoshimura T 《Immunology》2004,111(2):186-194
Tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the TNF superfamily, which is capable of inducing apoptosis in many cell types, including tumour and virus-infected cells, but rarely in normal cells. Expression of TRAIL mRNA and TRAIL receptors has previously been detected in neutrophils; however, the expression of TRAIL protein and the regulation of TRAIL and TRAIL receptor expression in these cells remain unknown. Here we report, for the first time, that neutrophils constitutively express TRAIL protein on their cell surface and that the TRAIL protein is shed during culture. TNF-alpha is a down-regulator of TRAIL expression, whereas IFN-gamma up-regulates the expression of TRAIL. Neutrophils did not express a detectable level of TRAIL-R1 or -R4, but constitutively expressed a low, but substantial, level of TRAIL-R2 and a high level of TRAIL-R3. Although the level of TRAIL-R2 was not significantly altered during culture under different experimental conditions, approximately 30% of TNF-alpha-treated cells rapidly lost their high-level TRAIL-R3 expression, whereas the majority of IFN-gamma-treated cells retained a high level of TRAIL-R3 expression. Anti-TRAIL neutralizing antibody significantly inhibited neutrophil apoptosis during cultures in medium alone, or in the presence of TNF-alpha or IFN-gamma. Thus, our study identified human neutrophils as a cellular source of TRAIL and suggests that neutrophil-derived TRAIL may play a role in immune surveillance. Our results also suggest a role for the TRAIL/TRAIL receptor system in neutrophil apoptosis. 相似文献
27.
A morphological study was made on a particular model of Shwartzman reaction which was so designed as to occur mainly in the liver with minimal influence to the other parts of the body. The study was mainly focused on its mechanism; the role of the granulocytes, Kupffer cells, platelets and precipitated fibrin. It was revealed that Kupffer cells were severely damaged by the first, preparative injection and the most conspicuous finding after the second, provocative injection was marked granulocytic infiltration followed by massive hepatic cell necrosis. The infiltrating granulocytes sticked to the endothelium, degenerated Kupffer cells, or other granulocytes and, often aggregated around precipitated fibrin. The erythrocytes in the sinusoid also showed aggregation after the provocative injection of the endotoxin, which was, however, rather loose and easily washed out from the sinusoid by perfusion. It is suggested from the above observations that aggregation of granulocytes as well as precipitated fibrin plays an important role to disturb blood stream mechanically and leads to massive necrosis in the liver. 相似文献
28.
Masakatsu Takashima Wataru Tanaka Hiroki Matsuyama Hayato Tajiri Hiroyuki Sakakibara 《Nutrients》2021,13(4)
Quercetin has been shown to have anti-obesity effects, but it is unknown whether these effects can be transmitted from mothers to their progeny. In this study, we investigated whether maternal quercetin consumption during pregnancy has a protective effect on high-fat diet–induced hyper lipid levels and overweight in progeny. Female mice consumed a control diet or a diet containing 1.0% quercetin during breeding. The male progeny were then divided into four groups that were (1) sacrificed at postnatal day 3; (2) born to dams fed the control diet and also fed the control diet (C-C), (3) born to dams fed the control diet and then fed a 30% high-fat diet (C-HF), or (4) born to dams fed the Q-diet and then fed the HF diet (Q-HF). Maternal consumption of quercetin did not affect body weight or blood lipid parameters in either dams or neonates at postnatal day 3. After 13 weeks, the Q-HF group exhibited greater body and liver weights, and higher blood cholesterol levels than the C-HF group. However, the total cholesterol/ high density lipoprotein (HDL)-cholesterol ratios in the Q-HF and C-C groups remained similar. In conclusion, maternal quercetin consumption does not appear to protect the next generation from high-fat diet–induced hyper cholesterol level in the blood and liver, and consequently overweight, but may help regulate the total cholesterol/HDL-cholesterol ratio. 相似文献
29.
We report a case of angiosarcoma of the breast and the autopsy findings. The patient was a 35-year-old premenopausal woman
who complained of a tumor in her left breast. We found a tumor measuring 55 mm in diameter in the lower external quadrant.
The tumor was elastic and soft, smooth surfaced, well-defined and mobile. Dimpling sign or change of skin color were not observed.
Clinically it was diagnosed as phyllodes tumor, but tumorectomy revealed primary angiosarcoma of the breast. Further extended
surgery was recommended, but the patient refused additional therapy. Histological findings revealed a free surgical margin
and neither lymph node metastasis nor distant metastasis were clinically observed. Seven months later, local recurrence in
the same breast was recognized and finally radical mastectomy was carried out. Histological findings showed recurrence of
angiosarcoma in the left breast but lymph node metastasis was not detected. Two months after mastectomy, metastases to the
cervical and thoracic vertebrae were observed and radiation therapy was performed. Sixteen months from onset, she died due
to multi-organ failure as general metastases of angiosarcoma. At autopsy, metastases to many organs including the digestive
system were observed. The incidence of primary angiosarcoma of the breast is low but its prognosis is poor. This case emphasized
the difficulties in clinical diagnosis and treatment for the angiosarcoma of the breast. 相似文献
30.
Tomosaburo Sakamoto Masahiko Miyata Makoto Nakamuro Masaaki Izukura Wataru Kamiike Hikaru Matsuda 《Surgery today》1994,24(12):1078-1080
A 51-year-old Japanese man who underwent a standard distal gastrectomy for cancer of the stomach developed abdominal pain when oral intake was commenced on the 6th postoperative day after an uneventful postoperative course. Complete obstruction of the jejunum led to a sudden deterioration in his general condition and a laparotomy was performed, revealing counterclockwise rotation of the mesenterium. The necrotic portion of the small intestine was removed, while 10 cm of the upper jejunum and 100 cm of the terminal ileum were preserved. His second postoperative course was uneventful apart from the development of intestinal hurry, which is now under medical control 9 months after his second laparotomy. 相似文献