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941.
Autophagy-mediated chemosensitizing effect of the plant alkaloid voacamine on multidrug resistant cells. 总被引:1,自引:0,他引:1
S Meschini M Condello M Marra G Formisano E Federici G Arancia 《Toxicology in vitro》2007,21(2):197-203
In our previous studies, voacamine, a bisindolic alkaloid extracted from Peschiera fuchsiaefolia, was examined for its possible capability of enhancing the cytotoxic effect of doxorubicin (DOX) on multidrug resistant (MDR) human osteosarcoma cells (U-2 OS-R). Voacamine induced in resistant cells a significant increase of drug retention and intranuclear location which became comparable to those observed in the parental sensitive counterparts (U-2 OS-WT). In the present study, the cell survival analysis and the electron microscopic observations confirmed the evident cytotoxicity of DOX on MDR cells after pre-treatment with the plant extract. Moreover, an increase of the reactivity of P-glycoprotein (P-gp) with the monoclonal antibody UIC2, which recognizes an epitope of the drug transporter in its functional conformation, was revealed, demonstrating that voacamine is a substrate of P-gp, thus acting as a competitive antagonist of the cytotoxic agent. Moreover, to investigate if the enhancement of the cytotoxic effect induced by voacamine could be due to an apoptotic process, we carried out the analysis of cell morphology after Hoechst staining and the quantification of apoptosis by Annexin V-FITC assay. These evaluations showed a very low rate of apoptosis in U-2 OS-R cells treated with voacamine and DOX given in association. In addition, the combined treatment induced ultrastructural modifications suggestive of autophagic cell death. In particular, transmission electron microscopy observations revealed the presence of numerous lysosomes and the formation of a large number of autophagosomes containing residual digested material. In conclusion, these findings seem to indicate that voacamine is capable of enhancing the cytotoxic effect of DOX on MDR cells by favouring a lethal autophagic process. 相似文献
942.
943.
T. Pinzer M. Reiß H. Bourquain K. G. Krishnan G. Schackert 《Acta neurochirurgica》2006,148(10):1085-1090
Summary Aspergillosis belongs to the group of mycotic diseases of paranasal sinuses. The invasive forms, and particularly the fulminant
forms, are potentially fatal. Isolated aspergillosis of the sphenoid sinus or the clivus is a difficult diagnosis, since the
often misleading clinical manifestations of this rare disease develop late. These patients become apparent by neurological
signs such as cavernous sinus syndrome, pseudotumor of the pituitary or the orbit. Diagnosis is often made intra-operatively
or on histological examination.
We report a case of invasive aspergillosis uniquely involving the sellar area revealed by clinical features suggesting a pseudotumor
of the pituitary. Although such lesions are almost always seen in immune suppressed subjects, in our case, the patient was
immune competent and had no past history of sinusitis.
The question of whether, and when to perform limited or extensive surgery remains an issue for discussion, owing to the rarity
of this disease honed by lack of experience. It depends on several factors: the kind of disease, the immunity, the subtype
of invasive fungal sinusitis and the degree of tissue invasion. 相似文献
944.
AIMS: In normotensive women with Type 1 diabetes and microalbuminuria we previously found preterm delivery (< 34 weeks) in 23% of the pregnancies. Antihypertensive treatment was initiated in late pregnancy when preeclampsia was diagnosed and diastolic blood pressure > 90 mmHg. From April 2000 our routine was changed and early antihypertensive treatment with methyldopa was initiated if antihypertensive treatment was given prior to pregnancy, if urinary albumin excretion (UAE) was > 2 g/24 h, or blood pressure > 140/90 mmHg. The present study describes the impact of this more aggressive antiypertensive treatment in the prevalence of preterm delivery. METHODS: The old cohort (1995-1999) consisted of 26 and the new cohort (2000-2003) of 20 pregnant women with Type 1 diabetes and microalbuminuria. All were referred before gestational week 17. RESULTS: The cohorts were comparable with regard to age, diabetes duration, prepregnancy body mass index, HbA1c, blood pressure 121 (13)/71 (8) vs. 121 (14)/73 (8) mmHg [mean (sd)] and early UAE 69 (16-278) vs. 74 (30-287) mg/24 h (geometric mean and range). Antihypertensive treatment was initiated in the old cohort at 29 (20-33) weeks, n = 9, and in the new at 13 (0-34) weeks, n = 10. The prevalence of preterm delivery before 34 weeks was reduced from 23% to zero (P = 0.02), preterm delivery before 37 weeks from 62% to 40% (P = 0.15) and preeclampsia from 42% to 20% (P = 0.11). Perinatal mortality occurred in 4% vs. 0%. Birth weight was 3124 (767) g vs. 3279 (663) g. CONCLUSION: Introduction of early antihypertensive treatment with methyldopa in normotensive pregnant women with Type 1 diabetes and microalbuminuria resulted in a significant reduction in preterm delivery before gestational week 34. 相似文献
945.
946.
M. M. Marchenko G. P. Kopyl’chuk I. A. Shmarakov O. V. Ketsa V. N. Kushnir 《Pharmaceutical Chemistry Journal》2006,40(6):296-297
The antitumor activity of 5-(5′,6′-benzocoumaro-3′-yl)methylaminouracil (BCMU) and its liposomal medicinal form was studied
in comparison to 5-fluorouracil (5-FU), a well-known antitumor drug widely used in oncological practice. The half-lethal dose
of BCMU is 14.8 ± 4.2 mg/kg, while the optimum effective dose of the drug is 6 mg/kg. In this dose, BCMU combines low toxicity
with significant antitumor activity, which is manifested by increased tumor growth inhibition (TGI) at a 19% increase in the
lifetime (LT) of experimental animals. The antitumor activity of the liposomal form of BCMU is quantitatively and qualitatively
superior to that of the nonmodified compound and 5-FU, which is manifested by the most pronounced TGI value and by a significant
LT increase.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 40, No. 6, pp. 6–7, June, 2006. 相似文献
947.
Noriyoshi Kurihara Hua Zhou Sakamuri V Reddy Veronica Garcia Palacios Mark A Subler David W Dempster Jolene J Windle G David Roodman 《Journal of bone and mineral research》2006,21(3):446-455
We targeted the MVNP gene to the OCL lineage in transgenic mice. These mice developed abnormal OCLs and bone lesions similar to those found in Paget's patients. These results show that persistent expression of MVNP in OCLs can induce pagetic-like bone lesions in vivo. INTRODUCTION: Paget's disease (PD) of bone is the second most common bone disease. Both genetic and viral factors have been implicated in its pathogenesis, but their exact roles in vivo are unclear. We previously reported that transfection of normal human osteoclast (OCL) precursors with the measles virus nucleocapsid (MVNP) or measles virus (MV) infection of bone marrow cells from transgenic mice expressing a MV receptor results in formation of pagetic-like OCLs. MATERIALS AND METHODS: Based on these in vitro studies, we determined if the MVNP gene from either an Edmonston-related strain of MV or a MVNP gene sequence derived from a patient with PD (P-MVNP), when targeted to cells in the OCL lineage of transgenic mice with the TRACP promoter (TRACP/MVNP mice), induced changes in bone similar to those found in PD. RESULTS: Bone marrow culture studies and histomorphometric analysis of bones from these mice showed that their OCLs displayed many of the features of pagetic OCLs and that they developed bone lesions that were similar to those in patients with PD. Furthermore, IL-6 seemed to be required for the development of the pagetic phenotype in OCLs from TRACP/MVNP mice. CONCLUSIONS: These results show that persistent expression of the MVNP gene in cells of the OCL lineage can induce pagetic-like bone lesions in vivo. 相似文献
948.
Chang Y Jung Hyo S Choi Jin S Ju Hyo S Park Tae G Kwon Yong C Bae Dong K Ahn 《The journal of pain》2006,7(10):747-756
The present study investigated the role of central metabotropic glutamate receptors (mGluRs) in interleukin-1beta (IL-1beta)-induced mechanical allodynia and mirror-image mechanical allodynia in the orofacial area. Experiments were carried out on male Sprague-Dawley rats weighing 230 to 280 g. After administration of 0.01, 0.1, 1, or 10 pg of IL-1beta into a subcutaneous area of the vibrissa pad, we examined the withdrawal behavioral responses produced by 10 successive trials of an air-puff ramp pressure applied ipsilaterally or contralaterally to the IL-1beta injection site. Subcutaneous injection of IL-1beta produced mechanical allodynia and mirror-image mechanical allodynia in the orofacial area. Intracisternal administration of CPCCOEt, a mGluR1 antagonist, or MPEP, a mGluR5 antagonist, reduced IL-1beta-induced mechanical allodynia and mirror-image mechanical allodynia. Intracisternal administration of APDC, a group II mGluR agonist, or L-AP4, a group III mGluR agonist, reduced both IL-1beta-induced mechanical allodynia and mirror-image mechanical allodynia. The antiallodynic effect, induced by APDC or L-AP4, was blocked by intracisternal pretreatment with LY341495, a group II mGluR antagonist, or CPPG, a group III mGluR antagonist. These results suggest that groups I, II, and III mGluRs differentially modulated IL-1beta-induced mechanical allodynia, as well as mirror-image mechanical allodynia, in the orofacial area. PERSPECTIVE: Central group I mGluR antagonists and groups II and III mGluR agonists modulate IL-1beta-induced mechanical allodynia and mirror-image mechanical allodynia in the orofacial area. Therefore, the central application of group I mGluR antagonists or groups II and III mGluR agonists might be of therapeutic value in treating pain disorder. 相似文献
949.
This study presents the case of a patient with necrobiosis or necrosing fascitis of the inguinal region, secondary to a complicated
Amyand’s hernia with a concomitant ipsilateral Richter’s hernia. The patient was treated with open trans-abdominal surgery
and hernia repair through the pre-peritoneal approach, plus anti-microbians, and thrice-daily wound cleansing and dressings
to the inguinal region. Evolution was satisfactory. There are no reports in the literature of a case such as this. 相似文献
950.
Priv.-Doz. Dr. Rüdiger Dissmann Joachim Schröder MD PhD Prof. Dr. med. Heinz Völler Prof. Dr. med. Steffen Behrens 《Clinical research in cardiology》2006,95(4):241-243
Summary During pacemaker implantation in a patient with permanent atrial fibrillation, it remained impossible to advance a passive
fixation lead with fins through the right atrium. However, a lead with a retractable screw easily passed the right atrium
and was positioned in the right ventricle. Transesophageal echocardiography revealed an extensive net–like perforated Eustachian
valve within the right atrium that had caused entrapment of the anchor fins during lead implantation. Remnants of embryonal
structures within the right atrium should be considered a rare possible barrier during pacemaker implantation. 相似文献