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91.
92.
Protective effect of Re-LPS antiserum on experimental multiple system organ failure. 总被引:2,自引:0,他引:2
This study examines the possible beneficial effect of Re-LPS (F515) antiserum on experimental multiple system organ failure (MSOF) in rabbits. The results showed that the plasma LPS level was significantly decreased, and it took a shorter period to clear up LPS in experimental than in control rabbits after receiving Re-LPS antiserum. Pretreatment with antiserum can markedly improve the function of the liver, lungs, kidneys, blood and gastrointestinal tract. The MSOF incidence in the group of rabbits receiving immune sera was only 11.2% and the survival rate was raised by about 40.0%. The results suggest that early passive immunotherapy may neutralize gut-derived endotoxin, inhibit endotoxin-induced mediators release and prevent development of severe complications due to sepsis. It is therefore postulated that LPS core antiserum may provide a prophylactic effect on the development of experimental MSOF.
相似文献
93.
重症胰腺炎动物模型制作及发病机理的研究 总被引:6,自引:1,他引:5
为探讨胰腺炎的发病机理,作者采用大鼠(n=58只)十二指肠结扎法和犬(n=46条)胰管内注射自身胆汁法制作重症胰腺炎的动物模型。该模型接近人类急性胰腺炎的发病因素,方法可靠,操作简便,费用便宜。前者适用于小动物实验,后者宜于大动物实验。作者认为胰管内压力增高和微生物是急性胰腺炎的重要条件;胰酶激活始动时间早在胰管内胆汁和肠液的反流后,胰酶激活的主要部位在腺泡细胞。 相似文献
94.
The effect of (+/-)-, (+)- and (-)-gossypol on testicular lactate dehydrogenase-X (LDH-X) was studied in vitro and in vivo. It was found that racemic gossypol and the two optical enantiomers had similar inhibitory effects on rat testicular LDH-X in vitro. However, neither racemic gossypol nor the enantiomers exhibited an inhibitory effect on testicular LDH-X in vivo. It is concluded that inhibition of testicular LDH-X is not likely to be the mechanism of the antifertility action of gossypol. The inhibition of testicular LDH-X in vitro by all three preparations of gossypol is probably non-specific. 相似文献
95.
Sixty specimens of breast cancer were assayed with ER-monoclonal antibody by immunocytochemical staining. Twenty-nine (48.33%) were nuclear estrogen receptor positive (ERn+). The number of ERn+ cancer cells decreased in the following sequence: mucinous carcinoma, invasive lobular carcinoma, invasive ductal carcinoma, and papillary adenocarcinoma. Two apocrine carcinomas were ERn-. ERn+ rate was higher in patients over 60 years of age (P less than 0.05). The amount of ERn+ cells was much greater in cancer cells than in the surrounding benign epithelial cells. This phenomenon may indicate that malignant cells are more hormone-dependent than benign cells. The results of immunocytochemical staining and steroid binding assay were compared. By immunocytochemical staining, twenty-four of fifty-seven cases (42.11%) were ERn+ and ERc+. Sixteen cases (28.07%) were ERn- and ERc-. This study showed that in a number of breast cancers ERs were positive in both cytoplasms and nuclei and the concordant rate was 70.18%. In the remaining cases 13 (22.81%), ERs were positive in the cytoplasm, and in 4 cases (7.02%) positive in nuclei only. Additionally, fifty-two out of 60 cases were assayed by 3H-estradiol and 3H-R5020 by means of steroid binding assay. Twenty-seven cases of them (51.92%) showed ERc+ and PRc+, and seventeen cases (32.69%) were ERc- and PRc-. Their correspondent rate was 84.61%. 相似文献
96.
Andres A; Morales JM; Praga M; Campo C; Lahera V; Garcia-Robles R; Rodicio JL; Ruilope LM 《Nephrology, dialysis, transplantation》1997,12(7):1437-1440
BACKGROUND: Cyclosporin has been shown to facilitate renal vasoconstriction
and to have an antinatriuretic effect. The existence of an interference of
cyclosporin with the vasodilating properties of endothelium mediated by
nitric oxide production could mediate these effects. On the other hand, the
infusion of the nitric oxide precursor L-arginine has been shown to induce
renal vasodilatation and to facilitate natriuresis in normal volunteers. We
have investigated the renal effects of the administration of an infusion of
L-arginine in renal transplant patients chronically treated with
cyclosporin. To facilitate the analysis of the data the effects of the
administration of a similar dose of cyclosporin on renal function during
the infusion of a vehicle were also investigated during the administration
of a vehicle of L-arginine. DESIGN: Ten male renal transplant patients,
chronically treated with cyclosporin and with a stable renal function were
studied during 2 consecutive days after the administration of the usual
morning dose of cyclosporin. The first day they received an intravenous
infusion of vehicle and the second the infusion of graded doses of
L-arginine (50, 100, 150 mg/kg/h) during 3 consecutive h. RESULTS: The
first day, after cyclosporin administration a significant fall (P <
0.01) was observed in natriuresis and kaliuresis in the absence of changes
in renal plasma flow and glomerular filtration rate. After the
administration of L-arginine significant (P < 0.01) increases of renal
plasma flow, glomerular filtration rate, and natriuresis were seen. The
increase in blood levels of cyclosporin after its administration did not
differ between days 1 and 2. CONCLUSION: These results indicate that
L-arginine facilitates renal vasodilatation and natriuresis in renal
transplant patients. Furthermore, the observed increase in sodium excretion
could indicate that L-arginine counteracts the antinatriuretic effect of
cyclosporin.
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97.
92例跟骨骨折后足部畸形功能障碍治疗探讨 总被引:6,自引:1,他引:5
本文对92例106足波及距下关节的跟骨骨折治疗后1~6年遗留足畸形、功能障碍的病例(PALey:舌型17足,中央压陷型53足,严重粉碎型36足)进行了分析和总结。作者强调解剖复位、牢靠固定、一期植骨、早期关节持续被动运动及不过早负重是预防跟骨骨折众多并发症的重要措施。 相似文献
98.
脉冲式电磁辐射对大鼠血脑屏障影响的量效关系 总被引:6,自引:1,他引:5
目的 研究脉冲式电磁辐射(EMR)对大鼠血脑屏障(BBB)影响的量效关系。方法 采用伊思蓝静脉注射,荧光显微镜下观察不同脉冲次数的EMR辐照对大鼠BBB开放的影响。结果 伊思蓝在EMR诱发的大鼠BBB开放局部呈现荧光斑;随着EMR脉冲次数(0~200次)的增加,荧光斑数量增加、面积增大;荧光斑在EMR组全脑的分布,以皮质、丘脑、下丘脑、小脑、尾壳核和延髓较多。结论 不同脉冲次数EMR诱发大鼠BBB开放程度不同,随脉冲次数增加,血管通透性增强,200次时达开放高峰,皮质区BBB开放最明显。 相似文献
99.
吸入麻醉药对人血浆和血小板血栓素B2生成与血小板聚集的影响 总被引:6,自引:0,他引:6
目的:探讨吸入麻醉剂氟烷、安氟醚和异氟醚对人血浆血栓素B2(TXB2),血小板TXB2生成与血小板聚集的影响。方法:血浆TXB2和血小板TXB2的生成量用放免分析法测量,血小板聚集率用比浊法测量。结果:吸入1MAC氟烷30分钟后,血浆TXB2浓度、二磷酸腺苷(ADP)和肾上腺素(E)诱导的血小板TXB2生成量与血小板聚集率显著下降,吸入1MAC安氟醚30分钟后,血浆TXB2浓度和血小板TXB2生成量与血小板聚集率亦显著下降,其降低的程度比氟烷轻。吸入1MAC异氟醚对上述指标无明显影响。血小板TXB2生成的减少与血小板聚集率的下降呈显著正相关。结论:氟烷显著抑制血小板聚集,安氟醚次之,异氟醚对血小板聚集无明显影响。其机制可能与氟烷和安氟醚通过抑制血小板上血栓素A2受体的亲和力,降低ADP和E诱导的血小板TXB2的生成有关。 相似文献
100.
本文以人红细胞膜为材料,应用荧光探针(ANS)及酶学研究方法,研究了丁卡因对AchE及红细胞膜脂之间的关系。结果显示,丁卡因对红细胞膜AchE有明显抑制作用,其半数抑制浓度为525μmol/L。丁卡因还能増加膜-ANS复合物荧光强度,双倒数及Scatchard作图分析表明,其使膜ANS复合物荧光强度增强的原因并非ANS荧光量子产率的改变,而是膜上ANS结合数量增加所致,这一效应与其时膜流动性影响是一致的。 相似文献