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991.
An unusual complication in a patient with Crohn enterocolitis is presented. Ultrasound and computed tomographic studies showed stationary gas in the portal vein, and a presumptive diagnosis of septic ascending portal thrombophlebitis was made. Emergency laparotomy was performed and the terminal ileum was excised for recurrent Crohn disease. Pathologic examination showed a fistula from the lumen of the inflamed segment to the superior mesenteric venous system. Autopsy 1 month later showed organizing thrombi and fecal debris in the portal venules.  相似文献   
992.
Inhibition of WY-14,643 induced hepatic lesion growth in mice by rotenone   总被引:2,自引:0,他引:2  
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   
993.
994.
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   
995.
996.
997.
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   
998.
Guidelines for blood utilization review   总被引:11,自引:0,他引:11  
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   
999.
Dale  GL; Friese  P; Hynes  LA; Burstein  SA 《Blood》1995,85(7):1822-1825
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   
1000.
Differential expression of HLA-DR antigens in subsets of human CFU-GM   总被引:2,自引:0,他引:2  
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   
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