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991.
Identification of Leishmania donovani isolates from different kala-azar foci in China by kDNA hybridization. 总被引:1,自引:0,他引:1
kDNA sequence homology of Leishmania donovani isolates from three types of kala-azar foci in China were analyzed by using dot and Southern hybridization with biotin- and 32P-labelled probes. The results revealed kDNA sequence heterogeneity among Leishmania donovani isolates from the three kala-azar foci: sequence homology between isolates of hill and desert foci was higher than that between hill and plain foci isolates. The kDNA hybridization technique was also found to be specific and sensitive for direct identification of Leishmania in animal tissues. In a preliminary survey, kDNA hybridization of cutaneous tissue blots of 71 dogs from endemic regions showed a positive rate of 40.8%, and the rate of double positive cases (touch blot hybridization and bone marrow smear) reached 91.3%. The direct identification of Leishmania in tissues by kDNA hybridization seems to be a useful and convenient method for epidemiological study and clinical diagnosis, especially for species/strain characterization. 相似文献
992.
通过纤维细胞集落(CFU-F)的培养,观察了急性早幼粒细胞性白血病(APL)的CFU-F,结果APL 患者较正常骨髓明显低下(4.3±1.63/2×10~5细胞)(n=9);完全缓解后则上升达正常水平(12.4±2.55/2×10~5)。体外试验,维甲酸(RA)加入CFU-F 培养系后,CFU-F 下降为3.11±1.24/2×10~5细胞,明显低于对照组8.5±1.57/2×10~5(P<0.05)。提示RA 对骨髓纤维细胞有抑制作用,此结果可能为RA 治疗骨髓纤维化提供初步依据。 相似文献
993.
Highly potent and selective inhibition of human immunodeficiency virus by the bicyclam derivative JM3100. 总被引:19,自引:5,他引:14 下载免费PDF全文
E De Clercq N Yamamoto R Pauwels J Balzarini M Witvrouw K De Vreese Z Debyser B Rosenwirth P Peichl R Datema et al. 《Antimicrobial agents and chemotherapy》1994,38(4):668-674
Bicyclams, in which the cyclam (1,4,8,11-tetraazacyclotetradecane) moieties are tethered via an aliphatic bridge (i.e., propylene, as in JM2763) are potent and selective inhibitors of human immunodeficiency virus type 1 (HIV-1) and type 2 (HIV-2) (E. De Clercq, N. Yamamoto, R. Pauwels, M. Baba, D. Schols, H. Nakashima, J. Balzarini, Z. Debyser, B. A. Murrer, D. Schwartz, D. Thornton, G. Bridger, S. Fricker, G. Henson, M. Abrams, and D. Picker, Proc. Natl. Acad. Sci. USA 89:5286-5290, 1992). We have now found that the bicyclam JM3100, in which the cyclam moieties are tethered by an aromatic bridge [i.e., phenylenebis(methylene)], inhibits the replication of various HIV-1 and HIV-2 strains in various cell lines at a 50% effective concentration (EC50) of 1 to 10 ng/ml, which is about 100-fold lower than the concentration required for JM2763 to inhibit HIV replication and at least 100,000-fold lower than the cytotoxic concentration (> 500 micrograms/ml). In primary T4 lymphocytes or primary monocytes, JM3100 proved inhibitory to HIV-1(IIIB) and several clinical HIV-1 isolates at an EC50 of less than 1 ng/ml. On the basis of time-of-addition experiments, JM3100 appeared to interact with a viral uncoating event, and this was further corroborated by an uncoating assay in which RNase sensitivity of [5-3H]uridine-labeled virions was monitored. In addition, but possibly mechanistically related, JM3100 blocks formation of infectious particles. JM3100 was also found to interfere directly with virus-induced syncytium formation, albeit at a higher concentration (1 to 2 microgram/ml) than that required for inhibition of viral replication. Following subcutaneous injection of 10 mg of JM3100 per kg of body weight to rabbits, anti-HIV activity was detected in serum corresponding to serum drug levels exceeding for at least 6 h by >100-fold the EC(50) required to inhibit HIV replication in vitro. When combined with either 3'-azido-2',3' -dideoxythymidine or 2',3' -dideoxyinosine, JM3100 achieved a additive inhibition of HIV replication, and when repeatedly subcultivated in the presence of JM3100, the virus remained sensitive to the compound for at least 30 passages (120 days) in cell culture. 相似文献
994.
In the presented studies stereometric analysis and spatial reconstruction was performed on two Langerhans cell (LC) types. One was free of LC-I and the other contained LC-II Birbeck granules in the perinuclear space. The presented stereometric analysis demonstrated significant differences between the so-distinguished two cell types. Differences were observed not only in the number and distribution of Birbeck's granules but also in the areas of smooth and rough endoplasmic reticulum, in the area of vesicles surrounding Golgi apparatus, in the volume of cisterns of the apparatus, and in the ratio of cell nucleus area to its volume. Differences noted between the two cell types were of quantitative character. They might result from different stages of differentiation of the cells from their precursors in the epidermis or from distinct functional stages of the cells. 相似文献
995.
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
996.
Twenty-eight breasts of 15 patients with macromastia underwent reduction mammaplasty from 1982 to 1989. We followed up these patients postoperatively for 6 months to 7 years. The follow-up time for 8 patients was over 1 year, and 4 patients over 5 years. And 3 patients labored and lactated. These 15 patients were satisfied with this operative results. The operative technology was based on Pitange's method. This method improved the site of the nipple, transposition of nipple-areola complex, and design of dermal pedicle, so that it had better effects in the breast shape, breast fixation and incision scar concealed. We suggest that the purpose of macromastia treated in reducing volume, improving breast shape, preserving lactating function. This paper also discusses the methods for nipple site, nipple-areola complex transposition, breast resection and mastopexy. 相似文献
997.
This paper reports the findings of a preliminary survey carried out in an Omani community to assess the prevalence of handicap amongst children, and its impact on the family. The sample comprised of 492 children less than 15 years of age. The disabilities identified related to chromosomal abnormality, genetic, perinatal, and infectious factors. The presence of mental retardation, with associated social taboos, confounds the problem in Oman. The study showed that, although some handicapped children may be accepted within the family, there was a sense of shame and rejection vis-à-vis the community. The prevalence of 2 per cent is only the tip of the iceberg. The study defines the sociocultural aspects of the Omani society which are conducive to the perpetuation of this important health and social problem. 相似文献
998.
A Golz S T Westerman L M Gilbert H Z Joachims A Netzer 《The Journal of laryngology and otology》1991,105(12):987-989
Although middle ear effusion was once described as the most common cause of vestibular disturbance in children, the association between glue ear and symptoms of dysequilibrium has never been quantified objectively. In this study the effect of middle ear effusion on the vestibular system of the inner ear was studied in a select group of children suffering from long lasting effusion in the middle ear with no evidence of infection at least one year prior to the study. The results were compared with results obtained from otitis free children, as well as from examinations of children after the insertion of ventilating tubes. The results of this study confirm the assumption that middle ear effusion has an adverse effect on the vestibular system, which can be resolved following the insertion of ventilation tubes. This effect may also contribute to the adverse effect that otitis media has on a child's development. 相似文献
999.
S. Dutkiewicz K. Debski A. Witoska P. Woszczyk Z. Pawluczuk 《International urology and nephrology》1994,26(6):599-604
Over a 36-month period 2800 patients were subjected to extracorporeal shock-wave lithotripsy (ESWL). A total of 5154 procedures
were done. Best results were seen with renal pelvic calculi (not larger than 2.5 cm in diameter). Fragments of crushed lower
calyceal calculi proved the most difficult to eliminate. As ureteral stone localization approached the bladder, the ESWL results
were poorer. Post-ESWL complications were proportional to the stone mass; the higher the mass the more numerous the complications
tended to be. Besides erythrocyturia and gross haematuria renal colic was the most frequent complication in almost 60% of
the patients. Less prevalent were impacted ureteral stones, subcapsular haematoma and fever. At our institution, thanks to
the ESWL method about 80% of the patients were spared surgery. 相似文献
1000.
从加强医疗病房的重危患餐巾选取因呼吸衰竭而给予呼吸机支持的患者40例,随机分为A组20例进行肠外营养(parenteral nutrition,PN)治疗,B组20例未行PN治疗。对通气/换气功能各指标进行分析,结果两组患者的呼吸频率、pH、PaO_2、PaCO_2及HCO_3~-无明显差异;A组氧分压与吸入气氧浓度比值轻度降低,而肺泡-动脉氧压差及肺内分流明显升高。提示PN中的脂肪乳和高糖可能是导致呼吸功能改变的重要因素。 相似文献