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21.
Preimplantation embryo morphology following early luteal phase anti-nidatory treatment with mifepristone (RU486) in the rhesus monkey 总被引:6,自引:0,他引:6
Ghosh D Lalitkumar PG Wong VJ Hendrickx AG Sengupta J 《Human reproduction (Oxford, England)》2000,15(1):180-188
The ultrastructural characteristics of peri-implantation stage embryos recovered on day 6 after ovulation from rhesus monkeys with or without mifepristone (RU486) treatment during the early luteal phase were examined in the present study. Monkeys were randomly allocated to two groups; group 1 animals were injected s.c. with 2 ml vehicle (1:4, benzyl benzoate: olive oil, v/v, n = 21) and group 2 animals received a single dose of mifepristone (2 mg/kg body weight, w/v, n = 30) in the same volume of vehicle on day 2 after ovulation in mated cycles. On day 6 after ovulation, female monkeys of both groups were laparotomized and their reproductive tracts were flushed to retrieve preimplantation stage embryos. Embryos that showed frank degeneration or desynchrony on gross microscopical examination were not included in the present study. Preimplantation embryo growth on day 6 after ovulation was significantly (P < 0.05) affected in the morula-blastocyst transition stage in mifepristone-treated monkeys compared with that in the control group of monkeys. Ultrastructurally, administration of mifepristone on day 2 after ovulation depressed preimplantation stage embryo development, characterized by loss of cell polarity, lack of mitochondrial maturity, and lack of differentiation in trophoblast cells. Furthermore, preimplantation embryos from mifepristone-treated animals displayed a higher occurrence of inter-blastomere space, intra-cytoplasmic vacuoles, myelinoid bodies, accumulation of lipid droplets, lysosomes, lipofuscins, autophagosomes and multivesicular bodies. Collectively, it appears that the developmental potential of preimplantation embryos was significantly compromised in mifepristone-treated cycles. 相似文献
22.
Masami Sakurai Nozomu Mori Ougi Horiuchi Nariaki Matsuura Yasushi Kobayashi 《Pathology international》1988,38(11):1453-1460
A primary tumor of the middle ear was examined histologically, histochemi-cally, immunohistochemically and ultrastructurally. Neuroendocrine cell differentiation, a carcinoid feature, was demonstrated by the presence of numerous argyrophil granules, as well as positive serotonin, glicentin, glucagon, and human pancreatic polypeptide (hPP) granules in some of the Grimelium-positive cells. Chromogranin A was also detected in the cells, but much less frequently than Grimelius-positive staining. Neither neuron-specific enolase (NSE) nor epithelial membrane antigen (EMA) was demonstrated in the tumor. Mucin was demonstrated only intraluminally. Electron microscopy revealed many typical neurosecretory granules in tumor cells, but no apical mucin granules. The tumor appeared to be benign, and there has been no sign of recurrence during a postoperative period of one year. ACTA PATHOL JPN38: 1453–1460, 1988. 相似文献
23.
Cellular characterization of blastocysts derived from rabbit 4-, 8- and 16-cell embryos and isolated blastomeres cultured in vitro 总被引:2,自引:0,他引:2
The purpose of this study was to investigate the developmental potential of isolated rabbit blastomeres under various culture conditions to gain insight into their ability to form the two cell lineages of a viable blastocyst. Intact embryos at the 4-cell, 8-cell, 16-cell stages and blastomeres isolated from 4-, 8- and 16-cell rabbit embryos (1/4, 1/8 or 1/16 blastomeres respectively) were cultured in drops of one of three different media, each supplemented with either fetal calf serum (FCS), bovine serum albumin (BSA) or polyvinyl alcohol (PVA). The effects of the extracellular matrix fibronectin (FN) on the development of isolated rabbit blastomeres were also investigated. Supplementation of the medium with FCS yielded a higher (P < 0.05) proportion of blastocysts than BSA or PVA, predominantly from 1/4 blastomeres. No major differences were found between the three basic culture media. In 1/4, 1/8 or 1/16 blastomeres, blastocyst formation rates were greater (P < 0.05) in groups cultured in matrix-free (54.5, 59.6 and 54.6% respectively) than in FN-coated groups (35.4, 46.0 and 26.1% respectively). Only in blastocysts derived from 1/4 blastomeres, were the numbers of inner cell mass (ICM) and total cells of blastocysts higher (P < 0.05) in FN-coated groups than in matrix-free groups (12.7 +/- 1.1 versus 8.5 +/- 0.7 ICM, 73.8 +/- 3. 7 versus 57.8 +/- 3.3 total cells). The percentage of blastocysts derived from single blastomeres with ICM cells decreased with increasing cell stage of the parent embryos in FN-coated (93.6, 78.3 and 44.0%, respectively) as well as matrix-free groups (96.2, 69.3 and 55.2%). In FN-coated groups, after 96 h (1/4) or 72 h (1/8 and 1/16) of culture, approximately 20-30% of blastomeres did not develop into normal blastocysts but formed sheets with 30-50 cells attached to the bottom of the dishes. These results indicate that the development of rabbit blastomeres shares important characteristics with those from mouse and domestic species and may thus aid in developing an efficient culture system for blastomeres, derived from human embryos. 相似文献
24.
The enzyme for the synthesis of epinephrine, phenylethanolamine-N-methyltransferase, has been localized, by an indirect immunofluorescent staining method, to a subpopulation of amacrine cells in the rat retina. The immunoreactive cells are located primarily in the inner nuclear layer and send a single process to the inner plexiform layer. Most of the immunoreactivity is found in the center of the inner plexiform layer. A small percentage of immunoreactive cell bodies were found in the inner plexiform layer and occasionally cells were observed in the ganglion cell layer. These epinephrine-containing amacrine cells are morphologically distinct from the dopamine-containing amacrine cells previously described by formaldehyde fluorescence and we speculate from reports in the literature that epinephrine-containing amacrine cells may play a role in modulating the activity of dopamine-containing amacrine cells. 相似文献
25.
The response of heat shock proteins 25 and 72 to ischaemia in different kidney zones 总被引:1,自引:0,他引:1
A. Schober E. Müller K. Thurau F. X. Beck 《Pflügers Archiv : European journal of physiology》1997,434(3):292-299
Induction of heat shock proteins (HSPs) following cell injury contributes to the protection of vital cell functions. It was,
therefore, of interest to study the effects of transient renal ischaemia on the abundance and distribution of two HSPs, HSP25
and HSP72, in renal tissue using Western-blot techniques. Analyses were performed on the supernatant (HSP25, HSP72) and pellet
(HSP25) of homogenates obtained from cortex (CX) and outer (OM) and inner (IM) medulla of the rat kidney immediately after
60 min of ischaemia followed by varying periods of reperfusion. Ischaemia of the left kidney caused HSP25 contents to decrease
in CX, OM and IM by 73, 89 and 54% respectively, compared with the corresponding zones of the contralateral control kidney.
This initial decrease in supernatant HSP25 was accompanied by an increased abundance of HSP25 in the pellet. Following reperfusion,
HSP25 contents in the supernatant gradually increased in CX and OM, reaching, after 24 h, values that were 5.4- and 2.5-fold
higher, respectively, than those in the control kidneys. After 7 or 14 days of reperfusion, HSP25 contents had not completely
normalised in CX, but had reached control levels in OM. In IM, the HSP25 content remained below control throughout the entire
reperfusion period. HSP72 (supernatant) was below the detection limit in the CX of the control kidney. Similar to the level
of HSP25, that of HSP72 was also markedly lower in OM and IM immediately after ischaemia. The intrarenal distribution of HSP72
and the sequence of zonal changes in HSP72 contents were similar to those observed for HSP25. These results are compatible
with the view that, during ischaemia and the initial reperfusion period, HSP25 migrates from the cytoplasmic compartment (supernatant)
into the nucleus and/or associates with cytoskeletal structures. The observation that both HSP25 and HSP72 are transiently
induced in CX and OM, but not in IM, may be explained by the fact that, while all kidney cells are exposed to ischaemic stress,
only inner medullary cells experience a major postischaemic attenuation of osmotic stress.
Received: 11 February 1997 / Received after revision and accepted: 26 March 1997 相似文献
26.
目的探讨应用NT-PC治疗髌骨骨折的方法及治疗结果。方法根据NT-PC结构及固定原理对30例髌骨骨折的治疗。结果30例髌骨骨折髌关节面均达到解剖复位,患者能下地行走,扶栏杆或徒手上下一层楼、屈膝平均达到90°的时间是1.5~3.5周。患膝关节伸、屈活动范围达到健侧水平的时间是2~10周。结论根据NT-PC的特点治疗髌骨骨折,尤其是粉碎性骨折,不但在术中容易得到髌关节面的解剖复位,而且术后能有效地将其维持,固定于解剖位直至骨质愈合。术后可早期活动,无需石膏固定,无膝关节功能障碍。 相似文献
27.
耳针分娩镇痛效果及对母儿的影响 总被引:3,自引:0,他引:3
目的 :探讨耳针镇痛的临床效果。方法 :对 6 8例正常足月初产妇临产后取耳穴、子宫穴、神门穴、交感穴、内分泌穴针刺镇痛 ,同时以 6 0例足月妊娠的正常产妇为对照组 ,不采取任何方法进行镇痛。记录 2组镇痛效果及产程、分娩方式、产后出血及新生儿评分的数值。结果 :耳针能协调子宫收缩、减轻疼痛、缩短产程 ,对分娩方式、产后出血量及新生儿阿氏评分均无影响。结论 :耳针用于分娩镇痛安全、简便、有效、便于推广 相似文献
28.
采用外耳道及鼓室再造术治疗先天性外耳道完全闭锁29例。统计各种外、中耳畸形情况,比较耳廓发育程度、颞骨相当于外耳道口处有无骨性小凹、术前听力损失程度与中耳畸形的关系,将术前的常规横断位CT检查结果与术中所见进行对照。结果显示,术前可通过耳廓发育程度、相当于外耳道口处有无骨性小凹、听力损失程度和颞骨CT扫描来综合估计中耳畸形情况,为术前了解手术难度和确定手术进路及方式提供一定的参考依据。 相似文献
29.
30.
Konrd S. Konrdsson Lars Holme Nielsen Bjrn I. R. Carlborg Britt Borgkvist 《The Laryngoscope》2000,110(2):264-264
Objectives: To elucidate the pressure transfer between intracranial and labyrinthine fluids in patients with well‐defined unilateral Meniere's disease. Study Design: Eleven patients previously exposed to hypobaric pressure agreed to be investigated further with the tympanic membrane displacement (TMD) technique. TMD was used to indirectly analyze perilymph pressure changes as the result of changes in body position. Methods: Repeated measurements for both the diseased and the healthy ears were made with the patients supine and then in a sitting position. The TMD parameters for the maximum inward displacement, the Vi, and the mean volume displacement, the Vm, were calculated and compared. Results: The paired comparison showed statistically significant larger Vi values for both ears in the supine position. A similar tendency was observed for the Vm value. This difference of the Vi was significantly larger for the diseased ear compared with the currently healthy ear. The results were compared to the audiometric and electrocochleographic results previously obtained on the same patients when they were subjected to hypobaric pressure. Patients who experienced the largest differences in hearing level thresholds in the lower frequencies also showed the greatest differences in TMD values as the result of postural changes. Conclusions: Despite the limited number, the statistically supported results suggest a relation between the efficiency of the routes of pressure transfer and the observed effect of hypobaric exposure. The results also indicate that for the patients tested, the routes of communication are more effective in the diseased ear than in the healthy ear—a condition that may relate to the pathogeneses of Meniere's disease. 相似文献