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991.
Xia Zhang Gildas Le Gal La Salle Valerie Ridoux Peter H. Yu Gong Ju 《Neuroscience letters》1996,210(3):169-172
Fos oncoprotein expression is a marker of neuronal activation following seizures. Here, using this method we examined the anatomical locations of muscimol-induced absence seizures in the rat forebrain. Six hours after a systemic injection of muscimol a massive Fos immunoreactivity appeared in the olfactory system, retrosplenial cortex and paraventricular thalamic nucleus, whereas other cortical areas contained low level of Fos expression. These results provide the first functional morphological evidence suggesting that these forebrain structures with Fos expression may play an important role in the pathophysiology of muscimol-induced absence seizures. 相似文献
992.
Chuen -Mao Yang Hui -Liang Tsao Chi -Tso Chiu Lir -Wan Fan Sheu -Meei Yu 《Pflügers Archiv : European journal of physiology》1996,432(4):708-716
The effects of increases in cellular adenosine 3′5′-cyclic monophosphate (cAMP) on 5-hydroxytryptamine-(5-HT-) induced generation
of inositol phosphates (IPs) and increases in intracellular Ca2+ ([Ca2+]i) were investigated using canine cultured tracheal smooth muscle cells (TSMCs). Cholera toxin and forskolin induced concentration-
and time-dependent cAMP formation with half-maximal effects (−logEC50) produced at concentrations of 7.0 ± 0.5 and 4.9 ± 0.4 respectively. Pretreatment of TSMCs with either forskolin or dibutyryl
cAMP inhibited 5-HT-stimulated responses. Even after treatment for 24h, these agents still inhibited the 5-HT-induced Ca2+ mobilization. The inhibitory effects of these agents produced both depression of the maximal response and a shift to the
right of the concentration response curves of 5-HT. The water-soluble forskolin analogue L-858051 [7-deacetyl-7β-(γ-N-methylpiperazino)-butyryl forskolin] significantly inhibited the 5-HT-stimulated accumulation of IPs. In contrast, the addition
of 1,9-dideoxy forskolin, an inactive forskolin analogue, had little effect on this response. Moreover, SQ-22536 [9-(tetrahydro-2-furanyl)-9-H-purin-6-amine], an inhibitor of adenylate cyclase, and both H-89 [N-(2-aminoethyl)-5-isoquinolinesulphonamide] and HA-1004[N-(2-guanidinoethyl)-5-isoquinolinesulphonamide], inhibitors of cAMP-dependent protein kinase (PKA), attenuated the ability
of forskolin to inhibit the 5-HT-stimulated accumulation of IPs. These results suggest that activation of cAMP/PKA was involved
in these inhibitory effects of forskolin. The AlF4
−-induced accumulation of IPs was inhibited by forskolin, suggesting that G protein(s) are directly activated by AlF4
−- and uncoupled from phospholipase C by forskolin treatment. These results suggest that activation of cAMP/PKA might inhibit
the 5-HT-stimulated phosphoinositide breakdown and consequently reduce the [Ca2+]i increase or inhibit both responses independently.
Received: 14 March 1996/Accepted: 10 April 1996 相似文献
993.
Fedotova YO 《Neuroscience and behavioral physiology》2000,30(1):75-80
The effects of systemic administration of thyroid, adrenal cortex, and sex hormones on learning ability, memory trace retention,
and behavior were compared in male rats. These studies showed that thyroid, corticosteroid, and sex hormones had no effect
on passive learning. Excess quantities of sex hormones disrupted active learning and subsequent reproduction of received information;
an excess of thyroid hormone improved the acquisition and retention of the active avoidance habit. Increases in the levels
of adrenal cortex hormones worsened active learning and the retention of memory traces, and also increased the level of behavioral
activity.
Translated from Zhurnal Vysshei Nervnoi Deyatel'nosti imeni I. P. Pavlova, Vol. 48, No. 6, pp. 980–988, November–December
1998. 相似文献
994.
药物对映体结构特异性对局麻药药代动力学的各个过程都有着很大影响,包括药物的吸收、蛋白结合率、代谢等。近年研究较多的罗哌卡因和左旋布比卡因作为单一的左旋对映异构体,因其良好的局麻效应和较小的全身毒性正引起广泛的关注。 相似文献
995.
利用纳米电化学传感技术进行癌症的早期检测是将来生物医学领域的一个重要发展方向.简要介绍了肿瘤早期检测用标志物的概念和电化学检测这些标志物的原理,对纳米粒子应用于电化学癌症早期检测技术的研究进展进行了详细的评述,最后对该领域的应用前景进行了展望. 相似文献
996.
子宫切除术对性生活质量的影响及其干预 总被引:5,自引:2,他引:5
目的 :了解子宫切除时宫颈去留对术后性生活质量的影响 ,并观察健康教育干预对提高患者术后性生活质量的作用。方法 :将因子宫良性病变而行子宫切除的病人分为全切组和次切组 ,每组再随机分为干预组和非干预组 ,分别进行术后性生活质量评分比较。结果 :1 在未经心理干预的子宫切除病人中次切组性生活质量评分高于全切组 (P <0 0 5 ) ;2 干预组术后性生活质量评分高于非干预组 (P <0 0 5 )。结论 :子宫切除时保留宫颈及手术前后的健康教育干预有利于患者术后性生活质量的改善 相似文献
997.
The connexin26 gene ( GJB2) has been shown to be responsible for DFNB1 and DFNA3 (Autosomal Recessive Hereditary Nonsyndromic Deafness Locus 1 and Autosomal Dominant Hereditary Nonsyndromic Deafness Locus 3). Two hundred ten independently ascertained Chinese probands with nonsyndromic hearing loss (NSHL) were evaluated for mutations in GJB2, including 43 probands from families with more than one sib with NSHL, likely indicating dominant inheritance, and sporadic cases of NSHL, compatible with recessive inheritance. Of the 210 probands, 43 (20%) were homozygous or heterozygous for mutations in GJB2. Four different mutations were identified: 35delG, 109G-A, 235delC, and 299-300delAT. It was confirmed that GJB2 mutations are an important cause of hearing loss in this population. Of these four mutations, 235delC was the most prevalent at 93%; yet the 35delG mutation, which is the most common GJB2 mutation in Caucasian subjects (Europeans and Americans), was found in low frequency in the present study. It appears from our limited data and reports from other East Asians that 235delC is the most prevalent GJB2 mutation in these populations. GJB2 mutations are consistent with ethnic predilections. 相似文献
998.
瞬目反射、脑干听觉诱发电位、经颅多普勒超声对椎基底动脉供血不足的诊断价值 总被引:2,自引:0,他引:2
目的:观察瞬目反射(BR)、脑干听觉诱发电位(BAEP)、经颅多普勒超声(TCD)对椎基底动脉供血不足(VBI)的诊断意义。方法:对41例已经临床确诊的VBI病人在间歇期进行BR、BAEP及TCD检查。结果:TCD、BR、BAEP异常率分别为83%、80%、68%。BR提示脑桥损害1例、延髓损害15例、广泛性脑干损害17例;BAEP发现内耳听力减退20例、脑干病变13例;TCD发现多血管流速异常14例、一支流速改变16例,有或伴有血管张力异常13例。结论:由于BR、BAEP反射路径不同,检测结果不尽一致。联合检查有助于对病损部位进行定位。TCD则有助于定性诊断 相似文献
999.
1000.
Yu Wen-Gong; Yamamoto Noriniko; Takenaka Hiroshi; Mu Jie; Tai Xu-Guang; Zou Jian-Ping; Ogowa Makoto; Tsutsui Tateki; Wijesuriya Rishani; Yoshida Ryotaro; Herrmann Steven; Fujiwara Hiromi; Hamaoka Toshiyuki 《International immunology》1996,8(6):855-865
The present studnt Investigates the molecular by which IFN-produced as a result of in vitroIL-12 addministration exertsits anty-tumor,rIL-12 was administered three or five times intomice bearing CDA1M fibrosarcoma, OV-HM ovarian carcinoma orMCH-1-A1 fibosarcoma. This regimen induced complete regressionof CSA1M and OV-HM tumors but only transient growth inhibitionof MCH-1-A1 tumors. The anty-tumor effects of Il-12 were associatatedwith enhanced induction of IFN-becouse these effects were abrogatedby pretreatment of hosts with anti-IFN- antibody.Exposure inin vitro of the three types of tumor cells to rIFN- resultedin moderate to potent inhibition of tumor cell growth.IFNstimulatedthe expression of mRNAs for an inducible type of NO synthasa(INOS)in CSA1M cells and indoleamine 2,3-dioxygenasa (IDO),an enzyme capable of degrading tryptophan, in OV-HM cells ,but induced only marginal levels of these mRNAs in MCH-I-ALcells. In association withiNOS gene expression, INF--stimulatedCSA1M cells produced a large amount of NO which functioned toinhibit their own growth in vitro. Although OV-HM and MCH-1-A1cells did not produce NO, they also exhibited NO susceptibility.Whereasthe tumor masses from IL-12-treated CSA1M-bearing mice inducedhigher levels of INOS (for CSA1M) or IDO and iNOS (for OV-HM)mRNAs,the MCH-1-A1 tumor mass expressed lower levels of iNOS mRNAalone.Moreover, massive infiltration of CD4+and CD8+ T cellsand Mac-1+ cells was seen only in the CSA1M and OV-HM tumors.Thus, these results indicate that IFN- produced after IL-12treatment induces the expression of various genes with potentialto modulate tumor cells and growth by acting directly on tumorecells or stimulating tumor-infiltrating lymphold cells and thatthe effectiveness of IL12 therapy is assoiated with the operation if these mechanisms. 相似文献