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991.
The effect of rotenone treatment on [4-chloro-6-(2,3-xylidino)-2-
pyrimidinylthio] acetic acid (WY-14,643) hepatic lesion growth in male
B6C3F1 mice was investigated. Following induction of hepatic focal lesions
by diethylnitrosamine (DEN) 35 mg/kg twice a week for 8 weeks, mice were
placed into one of the four treatment groups: group I, control NIH-07 diet
(control diet), group II, rotenone (600 mg/kg diet), group III NIH-07 diet
containing WY-14,643 (1000 mg/kg diet), and group IV, NIH-07 diet
containing WY-14,643 (1000 mg/kg diet) and rotenone (600 mg/ kg diet). Mice
were killed after 30 and 60 days of dietary treatment. The effect of
treatment with WY-14,643 and rotenone on hepatic lesion growth was examined
by estimating the number of focal lesions per liver and the relative volume
of focal lesions. WY-14,643 (group III) increased both the number and the
volume of focal lesions. In particular, an increase in number and volume of
basophilic lesions was seen. Co-treatment with WY-14,643 and rotenone
(group IV) decreased both the number and the volume of the total number of
focal lesions and basophilic foci compared with WY-14,643 treatment alone
(group II). Alterations in the growth of hepatic focal lesions was further
investigated by examining DNA synthesis and apoptosis within individual
lesions. WY-14,643 (group III) treatment increased the DNA synthetic
labeling index in all foci. Co-treatment of rotenone and WY-14,643 (group
IV) decreased focal DNA synthesis and mitosis and increased the incidence
of apoptotic hepatocytes. These data suggest that rotenone's ability to
inhibit WY-14,643-induced hepatic focal lesion growth was mediated through
a decrease in hepatic focal proliferation and an increase in focal
apoptosis.
相似文献
992.
993.
β-淀粉样肽鼠脑室内灌注制作阿尔茨海默病动物模型的实验技术研究 总被引:2,自引:0,他引:2
目的 探讨 β -淀粉样肽鼠脑室内灌注制作阿尔茨海默病 (AD)模型过程中的技术问题。 方法 经颅骨穿刺进入鼠侧脑室 ,以微渗透泵持续灌注 β -淀粉样肽 (Aβ) ,使Aβ弥散入脑室周围及皮层 ,造成与神经元相关的Aβ沉积等类似AD的病理变化。 4周后鼠脑冠状位连续切片 ,在普通光学显微镜下观察脑导管进入侧脑室的痕迹。结果 大鼠有 92 % (5 5 /6 0 )导管准确进入侧脑室 ,接近进入或在皮层 5 % (3/6 0 ) ,小鼠仅 4 3% (2 3/5 4 )导管进入侧脑室 ,接近进入或在皮层 31% (17/5 4 )。结论 大鼠脑室内灌注Aβ的方法可作为AD动物模型的方法之一。 相似文献
994.
995.
Real-time sonography in suspected acute cholecystitis. Prospective evaluation of primary and secondary signs 总被引:1,自引:0,他引:1
Ralls PW; Colletti PM; Lapin SA; Chandrasoma P; Boswell WD Jr; Ngo C; Radin DR; Halls JM 《Radiology》1985,155(3):767-771
Sonographic findings in 497 patients with suspected acute cholecystitis were analyzed prospectively. Combined use of primary and secondary sonographic signs led to excellent positive and negative predictive values. Positive predictive values for stones combined with either a positive sonographic Murphy sign (92.2%) or with gallbladder wall thickening (95.2%) were excellent for acute cholecystitis. Positive predictive value of these signs for patients requiring cholecystectomy was even higher (99.0%). Negative predictive values for combined use of primary and secondary signs to exclude acute cholecystitis were also excellent (95.0% for no stones and negative sonographic Murphy sign). Real-time sonography alone, using both primary and secondary signs, can be definitive in nearly 80% of patients with suspected acute cholecystitis. These patients require no further imaging evaluation. Sonography should be the screening test of choice in acute cholecystitis because it is cost effective, prospectively highly accurate, quick, and better at characterizing and detecting other abdominal lesions than cholescintigraphy. A proposed algorithm is described. 相似文献
996.
Guidelines for blood utilization review 总被引:11,自引:0,他引:11
L Stehling ; NL Luban ; KC Anderson ; MH Sayers ; A Long ; S Attar ; SF Leitman ; SA Gould ; MS Kruskall ; LT Goodnough ; et al. 《Transfusion》1994,34(5):438-448
Hospitals are required by accrediting agencies to perform blood utilization review. Specific areas that must be addressed are the ordering, distribution, handling, dispensing, and administration of blood components. Monitoring the effects of transfusion on patients is also required. The format of the review process and the criteria for appropriate blood utilization must be developed by each institution. This article provides examples of areas that can be reviewed and procedures that may be used. However, the suggested laboratory values must not be interpreted as defining indications or criteria for transfusion. Each transfusion committee, or its equivalent, is responsible for developing its own institutional blood utilization procedures and audit criteria. Review and approval by the medical staff prior to implementation are essential. The procedures must also be reviewed and revised on a regular basis. 相似文献
997.
Demonstration that thiazole-orange-positive platelets in the dog are less than 24 hours old 总被引:3,自引:1,他引:2
Approximately 6% of dog platelets are positive for staining with thiazole orange, a dye frequently used to stain ribonucleic acid. In this report, thiazole-orange positivity is shown to mark platelets that are less than 24 hours old. Dog platelets were derivatized in vivo with N-hydroxysuccinimido biotin such that greater than 95% of all platelets were biotinylated. Newly synthesized, nonbiotinylated platelets were then monitored by flow cytometry for their ability to bind thiazole orange. After biotinylation, the percentage of biotin-negative, thiazole-orange-positive platelets increased gradually from 0.72% at 30 minutes to 5.44% at 24 hours. These data indicate that thiazole-orange staining does label newly synthesized platelets. 相似文献
998.
Griffin JD; Sabbath KD; Herrmann F; Larcom P; Nichols K; Kornacki M; Levine H; Cannistra SA 《Blood》1985,66(4):788-795
Expression of HLA-DR surface antigens by granulocyte/monocyte colony- forming cells (CFU-GM) may be important in the regulation of proliferation of these cells. Using immunological techniques to enrich for progenitor cells, we investigated the expression of HLA-DR in subsets of CFU-GM. "Early" (day 14) CFU-GM express higher levels of HLA- DR than do "late" (day 7) CFU-GM. Among late CFU-GM, cells destined to form monocyte (alpha-naphthyl acetate esterase-positive) colonies express higher levels of HLA-DR than do CFU-GM destined to form granulocyte (chloroacetate esterase-positive) colonies. Because high- level expression of DR antigen was a marker for monocyte differentiation, we examined several lymphokines for their effects on both DR expression and in vitro commitment to monocyte differentiation by myeloid precursor cells. DR antigen density could be increased by more than twofold over 48 hours upon exposure to gamma-interferon (gamma-IFN), whereas colony-stimulating factors had no effect. This was associated with a dose-dependent inhibition of total CFU-GM number, and a relative, but not absolute, increase in the ratio of monocyte colonies to granulocyte colonies. Similarly, in day 7 suspension cultures of purified myeloid precursor cells, gamma-IFN inhibited cell proliferation and increased the ratio of monocytes to granulocytes. Thus, despite the induction of high levels of HLA-DR antigen on precursor cells (a marker of monocyte commitment), the dominant in vitro effect of gamma-IFN was inhibition of granulocyte differentiation. 相似文献
999.
大鼠原位肝移植模型建立方法的若干问题探讨 总被引:2,自引:0,他引:2
目的探讨建立大鼠原位肝移植模型的方法与技术。方法用改进的二袖套法行100例Lewis→BN大鼠原位肝移植,术中门静脉、肝下下腔静脉用袖套法吻合,肝上下腔静脉用缝合法吻合,胆管内支架法完成胆道重建。结果供体手术时间(30.9±5.0)min,供肝修整时间(10.0±3.0)min,受体手术时间(50.0±5.5)min,无肝期为(23.0±2.5)min。手术成功率为92%(术后存活2 d以上),1周存活率为87%,1个月存活率为84%。结论通过提高手术技巧,熟悉各种并发症的原因和预防处理措施,可以减少并发症的发生,提高手术成功率,延长大鼠术后存活时间。 相似文献
1000.