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41.
The authors describe the management by percutaneous drainage of a rare solitary tuberculous liver abscess in a 37-year-old woman. Open surgical drainage of such abscesses can be avoided using percutaneous drainage combined with transcatheter infusions of antituberculous agents. For the safe and successful use of this method three criteria must be met: the abscess should be unilocular, there must be a safe access route and a previously sterile compartment must not be contaminated. In addition a small (22 or 23 gauge) needle should be used for the initial puncture. 相似文献
42.
Zvi Bar-Shavit Ronald L. Horst Jean C. Chappel F. Patrick Ross Richard W. Gray Steven L. Teitelbaum M.D. 《Calcified tissue international》1986,39(5):328-333
Summary 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) is a potent inducer of monocytic differentiation of the human promyelocytic leukemia cell line, HL-60. We have noted that
25-hydroxyvitamin D3 (25(OH)D3) in high doses is also capable of promoting monocytic differentiation of this cell line. To test the possibility that the
latter activity is due to conversion of 25OHD3 to 1,25(OH)2D3 by HL-60, we exposed HL-60 cells to 25OHD3 and analyzed the products by HPLC and radioreceptor assay. When chromatographed in the traditional solvent system (isopropanol-hexane),
a new peak appears which migrates with authentic 1,25(OH)2D3. However, in a solvent system containing dichloromethane, 90% of the peak migrates with another metabolite, 19-Nor-10-Keto-25OHD3 (19-Nor-25OHD3). Production of this metabolite is enhanced by living cells and is synthesized by both virgin HL-60 and those which have
undergone differentiation. We next determined if authentic 19-Nor-25OHD3 also promotes differentiation of this cell. As assessed by appearance of the monocyte-specific surface antigen (63D3) and
macrophage-specific esterase activity, we find that this metabolite does, in fact, induce monocytic differentiation of HL-60
with a potency of approximately 1/200 that of 1,25(OH)2D3 and similar to that of 25OHD3. In agreement with the effect upon cell maturation, 19-Nor-25OHD3 displaces3H-1,25(OH)2D3 from its HL-60 receptor with an efficiency comparable to 25OHD3. Hence, HL-60 cells convert 25OHD3 to 19-Nor-25OHD3, and 19-Nor-25OHD3 induces monocytic differentiation of HL-60 with comparable efficiency to its precursor, 25OHD3. 相似文献
43.
A case of intracerebral malignant B cell lymphoma associated with encephalitis typical of Human Immunodeficiency Virus (HIV)
infection is described in a 4 year old child, with post-transfusion Acquired Immune Deficiency Syndrome (AIDS) and severe
pre-existing cystic encephalomalacia. This report further documents B cell lymphoma as the commonest cause of an intracerebral
mass, and an important cause of death in paediatric AIDS. That more than one pathological process may be responsible for neurological
symptoms in paediatric AIDS is also emphasised. 相似文献
44.
45.
Although psychological debriefing (PD) represents the most common form of early intervention for recently traumatized people, there is little evidence supporting its continued use with individuals who experience severe trauma. This review identifies the core issues in early intervention that need to be addressed in resolving the debate over PD. It critiques the available evidence for PD and the early provision of cognitive-behavioral therapy (CBT). Based on available evidence, we propose that psychological first aid is an appropriate initial intervention, but that it does not serve a therapeutic or preventive function. When feasible, initial screening is required so that preventive interventions can be used for those individuals who may have difficulty recovering on their own. Evidence-based CBT approaches are indicated for people who are at risk of developing posttraumatic psychopathology. Guidelines for managing acutely traumatized people are suggested and standards are proposed to direct future research that may advance our understanding of the role of early intervention in facilitating adaptation to trauma. 相似文献
46.
Christian J Streck Paxton V Dickson Catherine Y C Ng Junfang Zhou John T Gray Amit C Nathwani Andrew M Davidoff 《Clinical cancer research》2005,11(16):6020-6029
PURPOSE: Type I IFNs (IFN-alpha/beta) have shown significant antitumor activity in preclinical models but limited efficacy and significant toxicity in clinical trials. We hypothesized that the antitumor activity of type I IFNs could be enhanced by chronic, low-dose systemic delivery and sought to test this in murine neuroblastoma models. EXPERIMENTAL DESIGN: Continuous liver-generated expression of human IFN-beta (hINF-beta) was achieved through a gene therapy-mediated approach using adeno-associated virus vectors encoding hIFN-beta (AAV hINF-beta). Orthotopic localized retroperitoneal and disseminated models of neuroblastoma were established using three different xenografts. Immunohistochemical analysis and ELISA were used to evaluate the antiangiogenic effect of therapy. RESULTS: The development of both localized orthotopic (retroperitoneal) and disseminated neuroblastoma was prevented in all mice expressing hINF-beta. Continued growth of established retroperitoneal tumors, treated with AAV hINF-beta as monotherapy, was significantly restricted, and survival for mice with established, disseminated disease was significantly prolonged following administration of AAV hINF-beta. Analysis of treated tumors revealed a significant antiangiogenic effect. Mean intratumoral vessel density was diminished and expression of the angiogenic factors vascular endothelial growth factor and basic fibroblast growth factor were both decreased. Finally, combination therapy in which AAV hIFN-beta was used together with low-dose cyclophosphamide resulted in regression of both established retroperitoneal and disseminated disease. CONCLUSIONS: AAV-mediated delivery of hIFN-beta when used as monotherapy was able to restrict neuroblastoma growth due in part to inhibition of angiogenesis. When used in combination with conventional chemotherapy, AAV hIFN-beta was able to effect complete tumor regression. 相似文献
47.
R H Gray M C Smith D D Garner B N Cage R A Freeman 《Journal of mental health administration》1986,13(2):15-22
A multivariate analysis of the relationships between service attributes and physician perceptions was conducted as an approach to marketing substance abuse treatment services. The results of this attribute-perceptive-preference study indicate: the physician(s) on staff attribute makes the greatest contribution to perceived quality and efficiency; easy referral admission makes the largest contribution to accessibility perceptions; and providing feedback produces the greatest contribution to perceived continuity. The JCAH attributes neither adds to nor subtracts from the perceptions of any of the four perceptual attributes. Other findings indicate that perceived efficiency produces the greatest contribution to overall consumer preference. Quality perceptions make the second largest contribution to overall preference, followed by continuity and accessibility perceptions. 相似文献
48.
A role for calcitonin gene-related peptide in protection against gastric ulceration. 总被引:3,自引:0,他引:3 下载免费PDF全文
OBJECTIVE: The goal of this investigation was to determine the role of calcitonin gene-related peptide (CGRP) in gastric mucosal resistance to ulceration. SUMMARY BACKGROUND DATA: CGRP is a 37-amino acid peptide found in the peripheral ends of afferent gastric neurons. CGRP is known to inhibit acid secretion, stimulate mucosal blood flow, and stimulate release of somatostatin. METHODS: The release of CGRP in response to intragastric and intra-arterial administration of capsaicin in the isolated, vascularly perfused rat stomach was measured by radioimmunoassay. The molecular forms of CGRP released were analyzed by gel filtration chromatography. The effect of intravenous CGRP or intragastric capsaicin on gastric ulceration induced by 100 mmol/L HCl and indomethacin was studied in intact and endogenous CGRP-depleted rats. RESULTS: Intra-arterial capsaicin (concentration range, 10(-7) to 10(-5) mol/L) stimulated a prompt and sustained release of immunoreactive CGRP, of which 84% coeluted with rat 1-37 CGRP I by gel filtration. Intragastric capsaicin (range, 10(-5) to 10(-4) mol/L) failed to release CGRP into the vascular perfusate. In intact rats, intragastric capsaicin (10(-6) mol/L) or intravenous CGRP I (10 micrograms/kg/hr) reduced the number and area of mucosal lesions caused by HCl and indomethacin compared with the findings in control rats. Rats depleted of endogenous CGRP were more susceptible to gastric ulceration than were normal rats. Intragastric capsaicin failed to protect the mucosa of CGRP-depleted rats, whereas exogenous intravenous CGRP was effective. CONCLUSIONS: These data support the hypothesis that CGRP released from gastric enteric neurons mediates gastric mucosal resistance to ulceration by noxious agents. 相似文献
49.
Schwannomas account for only a small percentage of retroperitoneal tumours. Presentation is typically varied and non-specific and pre-operative diagnosis is difficult. Herein are described five cases of retroperitoneal schwannoma. Presentation was varied, ranging from abdominal pain, abdominal mass, obstructed labour or an incidental finding. All patients had either an abdominal computed tomography scan and/or ultrasound performed. Pre-operative biopsy either by fine needle aspiration (in one patient) or core biopsy in two patients was unhelpful. In four patients with smaller tumours, complete excision was possible with no apparent long-term morbidity and no clinical evidence of recurrent tumour with follow up from 3.5 months to 11 years. For the largest tumour, complete surgical excision was not attempted as it would have entailed significant morbidity. 相似文献
50.
Flow dynamics through spinal needles 总被引:2,自引:0,他引:2
We examined the flow pattern produced when liquid dye was actively injected into a fluid medium at various flows through five different commonly used spinal needles. At all flows, the Whitacre-type needles produced a directional stream exiting at an angle from the longitudinal axis. At intermediate rates the stream developed tracks which disappeared at faster rates. The Quincke needle always produced an undeviated stream of dye and did not form tracks at any flow rate. When a perspex plate (representing the spinal cord) was interposed in front of the needle, the dispersion of dye was always unidirectional from the Whitacre needle and bidirectional from the Quincke needle. The dye adhered to the surface of the plate as a concentrated film at slow rates and at faster rates it dispersed turbulently for both types of needle. 相似文献