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51.
人体子宫内膜血管内皮生长因子的研究 总被引:1,自引:0,他引:1
目的 :对人体子宫内膜增殖期 (n =3)、分泌期 (n =6 )和增生过长 (n =6 )标本 ,进行VEGF的免疫定位和半定量测定 ,了解雌激素对子宫内膜VEGF的影响。方法 :研究组用免疫组织化学方法 ,对照组用无关的免疫球蛋白代替第一及第二抗体 ,用辅助视频图像分析系统进行计算。结果 :增殖期VEGF在腺体 (P <0 .0 0 1)和间质 (P <0 .0 1)的浓度 ,明显高于分泌期和子宫内膜增生过长 ,总的看来 ,腺体的VEGF高于间质。结论 :雌激素提高子宫内膜的VEGF的含量 ,并与增殖晚期新的血管形成和血管通透性增加有关。此外 ,子宫内膜增生过长的腺体VEGF并不升高 ,提示人体子宫内膜的腺体生长和血管生成调节是不同的。 相似文献
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53.
Luteolin alleviates bronchoconstriction and airway hyperreactivity in ovalbumin sensitized mice 总被引:7,自引:0,他引:7
OBJECTIVE AND DESIGN: Asthma is an inflammatory disease of the airways and the current focus in managing asthma is the control of inflammation. In this study, we attempted to investigate the anti-asthmatic potential of a plant derived natural compound, luteolin. MATERIAL: We used a murine model of airway hyperreactivity, which mimicked some of the characteristic features of asthma. Male BALB/c mice (8-9 weeks) were used for this study. TREATMENT: Mice (n = 6) were sensitized by intraperitoneal (i. p.) injection of 10 mg of ovalbumin (OVA) on days 0, 7 and 14 followed by aerosol inhalation (5% OVA) treatments daily beginning from day 19 to day 23. To study its preventive effect, luteolin (0.1, 1.0, and 10 mg/kg body weight; daily) was administered orally during the entire period (0 to 23 day) of sensitization. To study its curative effect, mice were first sensitized and then luteolin (1.0 mg/kg body weight daily) was given orally from day 26 to 32. The airway hyperreactivity, immunoglobulin E (IgE) in the sera, and cytokines (IFN-gamma, IL-4 and IL-5) in the bronchoalveolar lavage fluid (BALF) were measured. RESULTS: Both during sensitization and after sensitization, luteolin, at a dose of 0.1 mg/kg body weight, significantly modulated OVA-induced airway bronchoconstriction and bronchial hyperreactivity (p < 0.05). Luteolin also reduced OVA-specific IgE levels in the sera, increased interferon gamma (IFN-gamma) levels and decreased the interleukin-4 (IL-4) and interleukin-5 (IL-5) levels in the BALF. CONCLUSION: Our study showed that luteolin treatment during and after sensitization significantly attenuated the asthmatic features in experimental mice. Therefore, luteolin could be used either as a lead molecule to identify an effective antiasthma therapy or as a means to identify novel anti-asthma targets. 相似文献
54.
Angie S. Price Amy K. Nelson Alip Ghosh Shyamasundaran Kottilil Joel V. Chua 《Journal of medical virology》2023,95(1):e28105
Retrospective data showed that when we administered ledipasvir/sofosbuvir (LDV/SOF) to patients with hepatitis B and C coinfection, there was a modest reduction in hepatitis B surface antigen (HBsAg). Therefore, we hypothesize that similar HBsAg reduction can be seen in hepatitis B virus (HBV) monoinfected subjects. Primary and secondary efficacy endpoints are the decline in HBsAg and HBV DNA at Week 12 from baseline, respectively. We conducted an open-label Phase 2 pilot study to evaluate the safety, tolerability, and antiviral activity of LDV and/or SOF for HBV. Eligible subjects were either suppressed on antivirals (Group B) or inactive chronic HBV (Group A, C, D). Group A and B received LDV/SOF. Group C and D received SOF 400 mg and LDV 90 mg, respectively. All subjects completed the study, and all related adverse events (AEs) were mild. No discontinuations due to AEs or hepatitis flare occurred. At Week 12, HBsAg decline (log10 IU/ml) was similar between Group A (0.399) and B (0.400), less in Group C (0.207), and none in Group D, and there was HBV DNA decline in the inactive chronic HBV groups. LDV and SOF are safe and well tolerated when given to chronic hepatitis B subjects and have modest antiviral activity, particularly when given in combination. 相似文献
55.
beta-Tethymustine, 1-[2- {bis(2'-chloroethyl)amino}ethyl]spiro[imidazolidine-4,2'-(1'H),3',4'-dihydronaphthalene]-2,5-dione, has been synthesised and LD50 value determined in Swiss male mice, which was found to be 100.00 mg/kg by single i.p. injection. The following three criteria, namely ascites cell count, ascites fluid measurement and increase in median survival times (MST) of drug-treated (T) over untreated control (C) mice, were studied for evaluation of its antitumour efficacy in vivo in three murine ascites tumours, namely Ehrlich ascites carcinoma (EAC), sarcoma-180 (S-180) and Dalton's lymphoma (DL). At the optimum dose range of 8.0 mg/kg (higher) to 4.0 mg/kg (lower) for 1-7 days treatment following tumour transplantation on day 0, it exhibited a very high percentage of inhibition of both the ascites cell and fluid in these models and displayed excellent ILS(max) value of 80 in EAC, 224 in S-180 and 240 in DL, respectively, showing 'curative' effect (2-3/6 mice having 90 days survival rate). It also demonstrated a high ILS value of 150 with one cure/six mice bearing S-180 for 6 days prior to drug therapy. Screening results were compared with two clinical drugs, cyclophosphamide and 5-fluorouracil, serving as positive controls. Its chemical alkylating activity was compared with nor-HN2 (NSC 10873) and spiromustine (NSC 172112). The results indicate that it possesses greater alkylating activity than nor-HN2 and comparable activity with spiromustine. 相似文献
56.
Bhatavdekar J Patel D Trivedi C Dave R Nadkarni S Karelia N Vora H Ghosh M Patel S Suthar T Doctor S Balar D 《Oncology reports》1994,1(1):255-257
Hormones are believed to play a dominant role as promoters in the growth and development of hormone-dependent cancers. Much less is known about the circulating hormones in male patients with oesophageal cancer. This lack of attention led us to evaluate the role of peptide and steroid hormones (by RIA) in male patients with oesophageal cancer (n=49). Blood samples of patients were collected pretherapeutically and data was compared with age matched controls (n=25). In this retrospective study, significantly high levels of FSH (P<0.02), LH (P<0.001) and prolactin (P<0.001) were observed with concomitant low levels of estradiol (P<0.001), DHEA-S (P<0.02) and testosterone (P<0.001) in patients when compared with respective controls. The patients when grouped according to anatomical site and histological type of the tumor, intergroup variation was not observed in these hormones. From our, study, it seems that hormonal imbalance or altered ratio of peptide and steroid hormones might be playing a significant role in the development and/or progression of oesophageal carcinoma in men. 相似文献
57.
S. B. Banerjee Anup Bhowmick T. K. Nandy L. M. Ghosh 《Indian journal of otolaryngology and head and neck surgery》1994,46(4):202-204
A rare case of Embryonal Rhabdomyosarcoma of the tympanomastoid region with paralysis of VIth and VIIth cranial nerve and development of ipsilateral loss of vision is reported. The case was first clinically diagnosed as a complicated case of C.S.O.M. with petrositis and facial palsy and was operated upon. Histopathological examination in the postoperative period proved it to be a case of Embryonal Rhabdomyosarcoma. 相似文献
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59.
Immunohistological localisation of vascular endothelial growth factor in human endometrium. 总被引:2,自引:0,他引:2
B Naresh J Sengupta V Bhargava G Kinra J Hu D Ghosh 《Indian journal of physiology and pharmacology》1999,43(2):165-170
Several polypeptide growth factors regulate epithelial and stromal development in endometrium under the influence of estrogen and progesterone, and thereby regulate growth and differentiation of endometrium during menstrual cycle. However, little is known about the angiogenic growth factors that may affect endometrial vasculature throughout each menstrual cycle. Vascular endothelial growth factor (VEGF) is suggestively an important angiogenic growth factor in the female reproductive tract. The aim of the present study was to immunolocalize and assess semi-quantitatively VEGF immunostaining in cells of proliferative phase (n = 3), secretory phase (n = 6) and hyperplastic (n = 6) human endometrial samples. VEGF concentrations were significantly higher in glandular (P < 0.001) and stromal (P < 0.01) compartments of proliferative stage endometrium compared with those in secretory stage and hyperplastic endometrial samples, with no difference in the scores for glandular and stromal compartments between secretory stage and hyperplastic endometrial samples. Generally, glandular expression of VEGF was higher as compared to stromal compartment. Thus, it appears that endometrial VEGF expression and concentration are enhanced by estrogen, and may be correlated with neovascularization and increased vascular permeability during late proliferative period. Additionally, there was no enhancement in VEGF expression in hyperplastic glands, suggesting that regulation of glandular growth and that of angiogenesis in human endometrium operate through different mechanisms. 相似文献
60.
The antagonist activity of the metabotropic glutamate receptor ligand (2S,1'S,2'S)-2-methyl-2(carboxycyclopropyl)glycine (MCCG) was examined using the [35S]GTPgammaS binding and forskolin (FSK)-stimulated adenosine 3':5'-cyclic monophosphate (cAMP) assays with recombinant Chinese hamster ovary (CHO) cells expressing the G protein-coupled human subtype 2 metabotropic glutamate (hmGlu2) receptor. Whereas MCCG proved to be a partial agonist in the GTPgammaS binding assay, it not only antagonized the agonist effect of (IS,3R)-ACPD in the cAMP assay but further produced an anomalous increase of the cAMP level relative to baseline. The anomalous MCCG response was also observed following treatment of the cells with MCCG in the absence of added agonist. Determination of the glutamate concentration in the incubate at the start and end of the cAMP reaction revealed the existence of micromolar concentrations of cellularly released glutamate throughout the course of the assay, reaching levels which exceeded its reported affinity for the mGlu2 receptor. Considering MCCG's partial agonist effect in the GTPgammaS binding assay and its pseudo-inverse agonist effect in the cAMP assay, available methods of estimating its antagonist potency were inappropriate since the classical Schild method and the alternative model suggested by Waud both assume the antagonist to lack a concentration-response relationship. We derived an alternate design and models that permit estimation of the pA2 (pAx), Kd and IC50 for antagonists which produce a concentration related effect when applied by themselves. With their use, the data acquired in both assays support the designation of MCCG as a competitive antagonist of the hmGlu2 receptor and provide similar pA2 estimates between assays. In addition, the newly derived models and design permit the determination of antagonist potency for partial and inverse agonists so characterized in studies employing the Schild design. 相似文献