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991.
José S A Belderbos Katrien De Jaeger Wilma D Heemsbergen Yvette Seppenwoolde Paul Baas Liesbeth J Boersma Joos V Lebesque 《Radiotherapy and oncology》2003,66(2):119-126
PURPOSE: To evaluate the feasibility of dose escalation in non-small cell lung cancer (NSCLC) using three-dimensional conformal radiation therapy. PATIENTS AND METHODS: The main eligibility criteria of the trial were: pathologically proven inoperable NSCLC, ECOG performance status or=grade 3 (SWOG), grade 3 early and grade 2 late esophageal toxicity or any other (RTOG) grade 3 or 4 complications). RESULTS: Fifty-five patients were included. Tumor stage was I/II in 47%, IIIA in 33% and IIIB in 20%. The majority of the patients received a dose of 74.3 Gy (n=17) or 81.0 Gy (n=23). Radiation pneumonitis occurred in seven patients: four patients developed a grade 2, two patients grade 3 and one patient a grade 4. Esophageal toxicity was mild. In 50 patients tumor response at 3 months follow-up was evaluable. In six patients a complete response was recorded, in 38 a partial response, five patients had stable disease and one patient experienced progressive disease. Only one patient developed an isolated failure in an uninvolved nodal area. So far the radiation dose was safely escalated to 87.8 Gy in group 1 (lowest rMLD), 81.0 Gy in groups 2 and 3 and 74.3 Gy in group 4. CONCLUSION: Three-dimensional conformal radiotherapy enables significant dose escalation in NSCLC. The maximum tolerable dose has not yet been reached in any risk group. 相似文献
992.
S. B. Greenberg Kristin L. Crisci Peter Koenig Brad Robinson Paul Anisman P. Russo 《Pediatric radiology》1997,27(12):932-935
Background. Abnormalities of the pulmonary arteries following palliative or corrective surgery for tetralogy of Fallot (TOF) are common.
Our purpose was to compare the usefulness of magnetic resonance imaging (MRI) and echocardiography in the post- operative
evaluation of the pulmonary arteries in children with TOF. Objective. Our hypothesis was that MRI is more sensitive than echocardiography in the detection of branch pulmonary artery abnormalities
in children with TOF. Materials and methods. Pulmonary artery MRI and echocardiography were performed in 20 children following palliative and/or corrective surgery for
TOF. MRI and echocardiography were compared in their ability to detect abnormalities of the pulmonary arteries. Angiographic
or surgical correlation was available in 15 children. A perfusion scan for confirmation of pulmonary artery patency was available
in one additional child. Results. Abnormalities of the branch pulmonary arteries identified by MRI included: absence or occlusion (2), focal stenosis (15),
hypoplasia (2), aneurysm (1), and non-confluence (1). Echocardiography could not adequately visualize the right and left branch
pulmonary arteries in eight and ten children, respectively. Echocardiography missed stenosis in 13 branch pulmonary arteries,
patency of hypoplastic pulmonary arteries in two children, non-confluence of the pulmonary arteries in one child, and a left
pulmonary artery aneurysm in one child. Abnormalities identified by MRI were confirmed in 16 children by angiography, surgery
or perfusion scan. Conclusion. MRI is more sensitive than echocardiography for the evaluation of branch pulmonary artery abnormalities in children following
surgery for TOF.
Received: 13 January 1997 Accepted: 31 July 1997 相似文献
993.
Paul S. Nassif Steven Q. Simpson Angelo A. Izzo Pamela J. Nicklaus 《The Laryngoscope》1997,107(9):1223-1227
Interleukin-8 (IL-8), a potent neutrophilic chemoattractant and inflammatory cytokine, is present in middle ear effusions (MEEs) of children with otitis media and is thought to be responsible for the accumulation of neutrophils in MEEs. We hypothesized that IL-8 concentration predicts the total number and proportion of neutrophils in MEEs. IL-8 concentration and total and differential cell counts were measured in MEEs of children undergoing tympanostomy tube placement for otitis media. IL-8 was present in 80 (98%) of 82 effusions. The mean ± SEM value for IL-8 was 7342 ± 847 pg/mL. The mean ± SEM count and percentage of neutrophils were 1.34 × 106 ± 3.44 × 105 and 70.6 ± 3.1%, respectively. IL-8 concentrations correlated positively with the total number(r = +0.30; P = 0.02) and percentage of neutrophils(r= +0.32; P = 0.01) in the effusion. Additionally, purulent effusions had greater IL-8 concentrations (P = 0.003) and greater neutrophil count (P = 0.03) than mucoid or serous effusions. We conclude that IL-8 is consistently present in MEEs of children and IL-8 concentration predicts the total number and proportion of neutrophils. Furthermore, IL-8 concentration and the total number of neutrophils correlate positively with the type of effusion. These results support the hypothesis that IL-8 recruits neutrophils to the middle ear in MEEs. 相似文献
994.
Jack L. Gluckman Zlatko P. Pavelic Hans-Jurgen Welkoborsky Wolf Mann Peter Stambrook Lyon Gleich Keith Wilson Paul Righi Louis G. Portugal John McDonald Paul Biddinger David Steward Peter Gartside 《The Laryngoscope》1997,107(9):1239-1244
Fifty-three patients with T1 squamous cell cancer of the floor of mouth and ventral surface of the tongue with a known clinical outcome were retrospectively analyzed and arbitrarily divided into “aggressive” and “nonaggressive” groups based on their clinical behavior. Various host and tumor factors were then evaluated in an attempt to determine whether the tumor behavior could have been predicted. The paraffin-embedded tumor specimens were evaluated for tumor differentiation, tumor thickness and tumor invasion, microvessel density, and p53 expression. In addition, a composite morphologic grading score was obtained by combining cell differentiation, nuclear polymorphism, mitosis activity, depth of infiltration, type of infiltration, and lymphatic infiltration. No single technique appeared capable of identifying “aggressive” behavior, although possibly an evaluation of composite factors might show promise in the future. 相似文献
995.
Paul D. Righi Edward C. Weisberger Paul R. Krakovits Robert D. Timmerman Michael K. Wynne Homayoon Shidnia 《The Laryngoscope》1997,107(11):1464-1468
Brachytherapy can be employed in the primary or salvage treatment of head and neck cancer. The advantage of brachytherapy is the stereotactic limitation of radiation exposure to noninvolved tissues. Wound complications associated with brachytherapy have been discussed only sporadically in the literature. This retrospective study examines 28 patients, 20 for initial treatment and eight for salvage, with varying site and stage head and neck cancer treated with brachytherapy in addition to external beam radiation therapy and/or surgery. The overall complication rate was 50% (14/28), with infection and minor flap breakdown being the most common problems. Tumor site in the primary treatment group was the only significant factor in wound complications. In the salvage group complications were minor and primarily related to flap coverage of brachytherapy catheters. 相似文献
996.
Jonathan D. Adachi Professor Everett J. Sargeant Professor Margaret A. Sagle Associate Professor David Lament Assistant Professor Paul D. Fawcett Obstetrician Gynaecologist William G. Bensen Associate Clinical Professor Matthew McQueen Chief Director Professor Darius J. Nazir Clinical Chemist Associate Professor Charles H. Goldsmith Professor Head 《BJOG : an international journal of obstetrics and gynaecology》1997,104(1):64-70
Objective To assess the effects of medroxyprogesterone acetate on bone density in women who have had a hysterectomy
Design Randomised, double-blind, placebo-controlled trial of medroxyprogesterone acetate 10 mg, 20 mg or placebo as an adjunct to oestrogen therapy.
Participants One hundred and twenty-three women, aged 18 to 45 years and currently receiving daily oestrogen, who presented at a university-based rheumatology practice.
Interventions The women were randomly assigned to receive either medroxyprogesterone acetate 10 mg, 20 mg or placebo daily beginning on day 15 of each month for one year. Forty-one women were randomised into each group.
Main outcome measure The primary outcome measurement was the percentage of change from baseline in bone mineral density of the lumbar spine (L2–L4). Secondary outcome measures included differences in femoral neck bone density, cholesterol and triglyceride levels between groups.
Results At one year, change in bone mineral density did not differ between either the treatment or placebo groups. Medroxyprogesterone acetate 20 mg and 10 mg led to statistically significant reductions in very low density lipoprotein cholesterol, total triglycerides, and very low density lipoprotein triglycerides when compared with placebo. Medroxyprogesterone acetate 20 mg also led to a statistically significant reduction in high density lipoprotein cholesterol, high density lipo-protein-2 cholesterol, and high density lipoprotein-2 triglycerides.
Conclusions Medroxyprogesterone acetate at either dose as an adjunct to oestrogen did not improve bone mineral density at one year when compared with placebo. Medroxyprogesterone acetate 10 mg may not adversely affect lipids. Medroxyprogesterone acetate 20 mg, however, did reduce high density lipoprotein cholestrol and therefore may increase cardiovascular risk. 相似文献
Design Randomised, double-blind, placebo-controlled trial of medroxyprogesterone acetate 10 mg, 20 mg or placebo as an adjunct to oestrogen therapy.
Participants One hundred and twenty-three women, aged 18 to 45 years and currently receiving daily oestrogen, who presented at a university-based rheumatology practice.
Interventions The women were randomly assigned to receive either medroxyprogesterone acetate 10 mg, 20 mg or placebo daily beginning on day 15 of each month for one year. Forty-one women were randomised into each group.
Main outcome measure The primary outcome measurement was the percentage of change from baseline in bone mineral density of the lumbar spine (L2–L4). Secondary outcome measures included differences in femoral neck bone density, cholesterol and triglyceride levels between groups.
Results At one year, change in bone mineral density did not differ between either the treatment or placebo groups. Medroxyprogesterone acetate 20 mg and 10 mg led to statistically significant reductions in very low density lipoprotein cholesterol, total triglycerides, and very low density lipoprotein triglycerides when compared with placebo. Medroxyprogesterone acetate 20 mg also led to a statistically significant reduction in high density lipoprotein cholesterol, high density lipo-protein-2 cholesterol, and high density lipoprotein-2 triglycerides.
Conclusions Medroxyprogesterone acetate at either dose as an adjunct to oestrogen did not improve bone mineral density at one year when compared with placebo. Medroxyprogesterone acetate 10 mg may not adversely affect lipids. Medroxyprogesterone acetate 20 mg, however, did reduce high density lipoprotein cholestrol and therefore may increase cardiovascular risk. 相似文献
997.
W. Paul Dmowski Janina Michalowska Nasiruddin Rana Jan Friberg Elizabeth McGill-Johnson Linda DeOrio 《Journal of assisted reproduction and genetics》1997,14(3):139-144
Purpose: The purpose of this study was to evaluate the clinical effectiveness of subcutaneous estradiol pellets in donor oocyte recipients
with an inadequate endometrial response.
Methods: The subjects were 13 women with ovarian failure and a maximal endometrial thickness <10 mm on standard estrogen regimens,
as demonstrated during mock and/or prior oocyte donation cycles. They underwent pellet implantation (100–250 mg of estradiol)
6–13 weeks before oocyte donation.
Results: Maximal (mean ± SD) endometrial thickness was 8.7±1.5 mm on standard regimens, in contrast to 11.7± 1.8 mm on pellets, while
estradiol levels were 674±844 and 815±706 pg/ml, respectively. The estradiol:estrone ratio on pellets was >1. There was 1
pregnancy with early loss during 10 cycles on other estrogen regimens and 12 pregnancies during 19 cycles on pellets. The
pregnancy and implantation rates were, respectively, 63 and 27% on pellets and 41 and 14% on standard regimens in historical
controls.
Conclusions: We conclude that estradiol pellets after a single administration provide constant estradiol levels extending into the first
trimester of pregnancy, a physiologic estradiol:estrone ratio, and a better endometrial response than standard estrogen regimens.
Implantation and pregnancy rates are higher. This approach may be especially suitable for recipients with a poor endometrial
response.
Presented at the IXth World Congress on In Vitro Fertilization and Assisted Reproduction, Vienna, Austria, April 3, 1995,
and the 51st Annual Meeting of the American Society for Reproductive Medicine, Seattle, Washington, October 7–12, 1995. 相似文献
998.
The field of molecular genetics continues to see an ever increasing number of applications to pediatric tumor analysis. Studies
in pediatric tumors have identified novel genes and other genetic changes, a large number of which reflect one of the following
mechanisms: (1) activation of proto-oncogenes; (2) loss of tumor suppressor genes; or (3) creation of novel fusion proteins. At least one of these mechanisms is operational in each of the following pediatric tumors:
neuroblastoma, Ewing sarcoma and peripheral primitive neuroectodermal tumor (pPNET), intra-abdominal desmoplastic small-cell
tumor, rhabdomyosarcoma, synovial sarcoma, and Wilms tumor. Out of this research has come not only an increased understanding
of oncogenesis but also, for each of the tumors listed above, diagnostic and/or prognostic markers that can be used by the
pathologist and oncologist to improve overall patient management.
Received November 20, 1997; accepted April 20, 1998. 相似文献
999.
In neonates with pulmonary atresia and intact ventricular septum the aims of therapy are maintenance of pulmonary blood flow
and right ventricular decompression in order to achieve right ventricular support of the pulmonary circulation. Recent developments
in interventional heart catheterization with pulmonary radiofrequency-assisted balloon valvuloplasty and ductal stent implantation
offer an alternative to the classical surgical approach. We report on a neonate with membranous pulmonary atresia and intact
ventricular septum, in whom a large interatrial right-to-left shunt via the foramen ovale persisted after radiofrequency-assisted
pulmonary balloon valvuloplasty on the 2nd day of life. The interatrial shunt prevented adequate right ventricular filling
and antegrade pulmonary perfusion leading to severe cyanosis (transcutaneous oxygen saturation 40%). In order to increase
pulmonary blood flow and raise left atrial pressure, the arterial duct was stented. After ductal stenting, prostaglandin was
discontinued and the transcutaneous oxygen saturation remained stable around 89%. At follow up after 7 weeks the foramen ovale
had decreased in size and only a small left-to-right shunt was present, documenting the effectiveness of this approach.
Conclusion Based on the present case we propose a stepwise interventional approach for the neonate with pulmonary atresia and intact
ventricular septum. If cyanosis persists after isolated pulmonary valvuloplasty despite adequate right ventricular function,
ductal stent implantation can reduce interatrial shunting and thus improve oxygen saturation.
Received: 12 January 1998 / Accepted: 15 February 1998 相似文献
1000.
Paul M. Lemen MD Thomas R. Wigton MD Amy J. Miller-McCarthey MD Dwight P. Cruikshank MD 《American journal of obstetrics and gynecology》1998,178(6):1251-1256
Objective: Our purpose was to determine the incidence of gestational diabetes mellitus in an adolescent population and to determine the cost of screening. Study Design: A retrospective review of 509 adolescent pregnancies was performed. The incidence of gestational diabetes mellitus was determined and the cost of screening analyzed. Results: Five hundred nine adolescent pregnancies were screened for gestational diabetes mellitus with a 1-hour, 50 gm oral glucose challenge test. Twenty-three of the screens (4.5%) had positive results at a plasma glucose level of ≥140 mg/dl. Three-hour 100 gm oral glucose tolerance tests were performed on screen-positive women, six of whom were diagnosed with gestational diabetes mellitus, for an incidence of 1.18%. The cost per case diagnosed was $2733. Conclusions: The incidence of gestational diabetes mellitus in an adolescent population is low. The cost of universal screening may be prohibitive in this population. Large prospective studies are needed to better analyze outcome data and efficacy of screening in adolescent pregnancies. (Am J Obstet Gynecol 1998;178:1251-6.) 相似文献