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61.
Neurotrophic effects of hippocampal target cells on developing septal cholinergic neurons in culture 总被引:2,自引:0,他引:2
The influence of hippocampal target cells on the development of cholinergic septal neurons was studied in rotation-mediated reaggregating cell cultures. Brain cells from 15-day-old mouse embryos were obtained from: septum, containing cholinergic cells which project to the hippocampus; hippocampus which contains target cells for the septal cholinergic neurons; and cerebellum, containing cells which are not targets for the septal cholinergic cells. The cells were then cultured for 3 weeks in a rotary incubator in the following combinations: septal cells alone; hippocampal cells alone; cerebellar cells alone; septal-hippocampal cells together; and septal-cerebellar cells together. After harvesting, fixation, and embedding, 50 micron sections were cut and processed for visualization of acetylcholinesterase activity. Sections from reaggregates containing either hippocampal or cerebellar cells alone contained only a few acetylcholinesterase-positive cells, but no positive fibers. Sections from septal-hippocampal coaggregates revealed a pattern of well-defined, fine-caliber acetylcholinesterase-positive fibers with extensive arborizations and varicosities suggesting axonal proliferation. In septal-cerebellar coaggregates, acetylcholinesterase-positive fibers appeared to be degenerating and distinct areas were observed which were essentially devoid of acetylcholinesterase fibers. In some experiments, either cerebellar or hippocampal cells were labeled with wheatgerm agglutinin-rhodamine prior to culture in order to identify these cells in the resulting reaggregates. Analysis of sections from these studies showed that acetylcholinesterase fibers were excluded from regions of coaggregates containing cerebellar cells, but were present in regions of coaggregates containing hippocampal cells. Finally, cell counts of acetylcholinesterase-positive cells in the various combinations revealed that these putative cholinergic neurons were significantly more numerous in septal-hippocampal coaggregates (271 +/- 19 per 10(6) septal cells added) than in septal reaggregates (38 +/- 6 per 10(6) septal cells added) or septal-cerebellar coaggregates (85 +/- 29 per 10(6) septal cells added). These results, taken together, suggest that hippocampal target cells influence the development and survival of cholinergic neurons. 相似文献
62.
Joseph H Chewning Hugo Castro-Malaspina Ann Jakubowski Nancy A Kernan Esperanza B Papadopoulos Trudy N Small Glenn Heller Katharine C Hsu Miguel A Perales Marcel R M van den Brink James W Young Susan E Prockop Nancy H Collins Richard J O'Reilly Farid Boulad 《Biology of blood and marrow transplantation》2007,13(11):1313-1323
Graft failure is associated with a high mortality rate. To date, regimens invoked for second transplants have resulted in inconsistent engraftment with high transplant-related mortality (TRM). We here report 16 consecutive patients, aged 4-59 years, who received second HSCT (HSCT-2) at a median of 45 days following primary or secondary failure of an initial unmodified (N = 3) or T cell-depleted (TCD) (N = 13) HSCT (HSCT-1). HSCT-1 was administered after myeloablative total body irradiation (TBI)- or alkylator-based conditioning for acute leukemias (N = 7), MDS (N = 6), CML (N = 2), and Fanconi anemia (N = 1). All patients experienced 1 or more infectious complications between HSCT-1 and HSCT-2, and 10 patients had active infections at the time of HSCT-2. Cytoreduction regimens used for HSCT-2 included fludarabine (Flu) in combination with cyclophosphamide (CTX) (N = 9), or thiotepa (Thio) (N = 5). In addition, 1 patient received Flu alone and 1 patient Thio combined with CTX. Antithymocyte globulin (ATG) (N = 11) or Alemtuzumab (N = 3) was added pretransplant to prevent rejection. For HSCT-2, donors included HLA-matched (N = 3) or mismatched (N = 8) related, or matched (N = 2) or mismatched (N = 3) unrelated donors. The primary graft donor was used in 6 of 16 cases. The grafts administered were unmodified peripheral blood stem cell transplantation (PBSCT) (N = 5) or bone marrow transplantation (BMT) (N = 3), TCD PBSCT (N = 8). All patients achieved engraftment at a median of 12 days and evaluable patients achieved complete donor chimerism. Six patients are alive with a median follow-up of 49 months, including 4/9 conditioned with Flu/CTX. In this series, outcome was statistically superior for younger patients (相似文献
63.
To evaluate whether nitric oxide (NO) is an appropriate test gas for assessing pulmonary gas exchange, we determined the
rates of disappearance from the alveolar space (λ) of NO and singly and doubly 18O-labelled carbon dioxide (C16O18O, C18O2) by performing single-breath manoeuvres on seven artificially ventilated rabbits. By exploiting unique features of both isotopic
species and by analysing pulmonary gas transport and λ values with a commonly used model, we found that diffusion forms 98±6%
(mean ± SD) of the overall resistance to alveolar-capillary NO transfer. This means that measurements of pulmonary NO uptake
reveal the entire diffusive properties of the alveolar-capillary membrane, because the extremely fast binding of NO to haemoglobin
negates the ”reactive” component within red blood cells of pulmonary capillaries.
Received: 8 May 1998 / Received after revision: 12 August 1998 / Accepted: 17 August 1998 相似文献
64.
65.
Lupus vulgaris responding to double antituberculous therapy 总被引:1,自引:0,他引:1
G L Heller G P Pavlidakey K Hashimoto M Greenberg M Rosenberg 《Cutis; cutaneous medicine for the practitioner》1984,34(5):481-483
A patient with a 3 by 4 cm ulcerated lesion on the nose and upper lip in whom previous antibiotics and antifungal treatments for a "mixed infection" were of no avail is presented. Her history revealed that she has had pulmonary and pharyngeal tuberculosis and subsequently scrofuloderma of cervical lymph nodes. She eventually responded well to isoniazid, rifampin, and pyridoxine therapy. 相似文献
66.
Social class and ischaemic heart disease: use of the male:female ratio to identify possible occupational hazards. 总被引:4,自引:1,他引:3
R F Heller H Williams Y Sittampalam 《Journal of epidemiology and community health》1984,38(3):198-202
In England and Wales there has been an increasing excess of ischaemic heart disease death rates among men and women of social classes IV and V compared with those in classes I and II and this excess is greater in young than in old adults. The male excess over women in IHD death rates is much greater in social classes I and II than in classes IV and V. Although men in professional occupations are at low risk for IHD compared with men in other occupations, women married to professional men are at an even lower risk compared with other women. Also, women married to men in unskilled occupations have relatively higher IHD rates than their husbands. These patterns are not seen for "all causes," cerebrovascular disease, chronic bronchitis, or stomach cancer, where the social class mortality gradients are similar in men and women. There may thus be factors associated with professional occupations that increase the risk of IHD despite the relatively low death rates of men engaged in them. In addition there may be factors operating in women in social classes IV and V that put them at a particularly high risk for the development of IHD. 相似文献
67.
Bahram Biglari Raban Arved Heller Manuel Hrner Andre Sperl Tobias Bock Bruno Reible Patrick Haubruck Paul Alfred Grützner Arash Moghaddam 《The journal of spinal cord medicine》2021,44(2):229
Context/objective: Examining hemoglobin (Hb) dynamics with regard to the potential of neurological remission in patients with traumatic spinal cord injury (TSCI).Design: Prospective Clinical Observational Study.Setting: BG Trauma Centre Ludwigshafen, Department of Paraplegiology, Rhineland-Palatinate, Germany.Methods: From 2011 to 2017 a total of 80 patients with acute spinal injury were enrolled and divided into three groups: initial neurological impairment either with (G1; n = 33) or without subsequent neurological remission (G0; n = 35) and vertebral fractures without initial neurological impairment as control group (C; n = 12). Blood samples were taken for 3 months at 11 time-points after injury. Analyses were performed using routine diagnostics.Outcome measures: Multiple logistic regression was used to determine the prognostic value of Hb regarding neurological remission respecting clinical covariates.Results: Data showed elevated mean Hb concentrations in G1 from the third day to 1 month compared to G0, Hb levels were significantly higher in G1 after 3 days (P = 0.03, G1 > G0). The final multiple logistic regression model based on this data predicting the presence of neurological remission resulted in an AUC (area under the curve) of 80.5% (CI: 67.8%–93.2%) in the ROC (receiver operating characteristic) analysis.Conclusion: Elevated Hb concentrations are associated with a higher likelihood of neurological remission. Elevated concentrations of Hb in G1 compared to G0 over time might be linked to both a better initial oxygen supply response and a decreased ECM (extracellular matrix) degradation highlighting the role of Hb as a valuable biomarker for neural regeneration after TSCI. 相似文献
68.
K. D. Heller A. Prescher K. W. Zilkens R. Forst 《Surgical and radiologic anatomy : SRA》1997,19(3):133-137
Summary An anatomic study was undertaken to establish whether positioning of the leg and surgical approaches for total hip replacement (THR) cause changes in the femoral v. which may contribute to the development of deep vein thrombosis (DVT). The patency of 32 femoral vv. of 18 cadavers was inspected at different levels during simulated THR. Before and after removal of the femoral head through a transgluteal or posterior approach, a wide-angle endoscope was inserted into the femoral v. via the external iliac v. Blood flow was simulated by proximal irrigation with saline through the popliteal v. After removal of the femoral head distinct changes were observed in both approaches. In the transgluteal approach the changes were dependent on the degree of adduction and the body build of the cadaver. Initially, an oval form was seen in a constricted lumen with an increasingly oblique oval deformation and a final facet-like closure, usually at about 5 to 7.5 cm below the inguinal ligament. In total adduction this stenosis occured regardless of build. Using a posterior approach, the necessary internal rotation caused a closure of the vein in 50% of cases. In combination with flexion and adduction there was stenosis in all cadavers regardless of body build. Our results indicate that the duration of the adducted position of the thigh during THR via a transgluteal approach should be minimised, as there is a reduction in blood flow with even minor degrees of adduction. In the posterior approach the stenosis occurs earlier, and is independent of the build of the cadaver.
Étude anatomique de la sténose de la veine fémorale au cours des arthroplasties totales de hanche
Résumé L'étude anatomique a été réalisée pour établir la relation entre les différentes positions du membre inférieur au cours des arthroplasties totales de hanche et la survenue d'une thrombose veineuse profonde. Cette étude a été réalisée sur 18 cadavres, dont 32 vv. fémorales ont pu être examinées à différents temps de l'arthroplastie totale de hanche, avant et après ablation de la tête fémorale, par voie trans-glutéale ou par voie postérieure. Un endoscope (grand angle) a été introduit dans la v. fémorale par la v. iliaque externe. Le flux sanguin a été simulé par irrigation antérograde avec du sérum salé à travers la v. poplitée. Après l'ablation de la tête fémorale, il a été noté des différences significatives entre la voie d'abord trans-glutéale et la voie d'abord postérieure pour ce qui concerne l'aspect de la lumière de la v. fémorale et le flux sanguin. En ce qui concerne la voie trans-glutéale, ces modifications dépendaient du degré d'adduction et de la corpulence du cadavre. L'aspect de la lumière de la v. fémorale était initialement ovale, puis évoluait progressivement vers la sténose complète qui se situait à peu près entre 5 et 7,5 cm audessous du ligament inguinal. En adduction complète de la cuisse, la sténose se produisait, quelle que soit la corpulence du cadavre. En ce qui concerne la voie d'abord postérieure, la rotation médiale, indispensable à l'accès pour la mise en place de l'élément prothétique fémoral, causait une sténose de la v. fémorale dans 50% des cas. En ce qui concerne la combinaison des mouvements d'adduction et de flexion de la hanche, elle était responsable d'une sténose de la v. fémorale dans tous les cas, et ceci quelle que soit la corpulence du cadavre. Nos résultats indiquent que le durée de la position d'adduction de la cuisse durant l'arthroplastie totale de hanche par voie transglutéale devrait être diminuée car la réduction du flux sanguin dans la v. fémorale survient, même pour des petits degrés d'adduction. Dans la voie d'abord postérieure, la sténose survient plus tôt, elle ne dépend pas de la corpulence du cadavre.相似文献
69.
C. Dawn DeLozier Ray M. Antley Rick Williams Neil Green Richard M. Heller David Bixler Eric Engel John M. Optiz 《American journal of medical genetics. Part A》1980,7(3):391-403
Described here are two patients with a newly recognized syndrome of bone and cartilage maldevelopment which, we believe, results from a single embryonic defect, probably of genetic origin. The cardinal manifestations of this association are craniosynostosis, radiohumeral synostosis (RHS), and femoral bowing. Specific secondary defects include midface hypoplasia with characteristic facial appearance and ears, neonatal femoral fractures, and multiple minor anomalies of the limbs. Though the differential diagnosis includes such disorders as the campomelic syndrome, osteogenesis imperfecta (OI) and certain of acrocephalosyndactyly syndromes, the unique combination of clinical and radiographic abnormalities allows ready differentiation. The cause cannot be determined from these two cases. 相似文献
70.
同种异体黑素细胞移植治疗白癜风 总被引:2,自引:2,他引:0
0 引言 白癜风患者免疫紊乱 ,黑素细胞 (melanocyte,MC)异体移植有可能不被排斥 ,治疗如成功将有很大临床前景 [1 ] .探索同种异体黑素细胞移植后的效果很有意义 .1 病例报告 女 ,2 7岁 ,确诊白癜风 (稳定期 ) ,患者皮肤自幼出现色素脱失斑 ,逐渐增多扩大 . 1996年外用“敏白灵”,前2 mo有效 . 1999- 0 7外用补骨酯酊 ,日服 5 g· L- 1 硫酸铜 10m L和中药 1剂 ,转移因子 4m L ,sc,1· 2 d- 1 .皮损缩小 ,4mo后稳定 .用健康男青年环切的包皮培养 MC,第 4代大约80 %融合时 ,用 2 .5 g· L- 1 胰酶消化 5 min,加入含 2 0 0 g·L- 1小… 相似文献