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1.
ObjectivesTo fill an empirical gap in the literature by examining changes in quality of care measures occurring when multispecialty clinic systems were acquired by hospital-owned, vertically integrated health care delivery systems in the Twin Cities area.ConclusionsMoving a clinic system into a vertically integrated delivery system resulted in limited increases in quality of care indicators. Caution is warranted when the acquisition causes disruption in referral patterns. 相似文献
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3.
Robert J. Town Douglas Wholey Roger Feldman Lawton R. Burns 《Health services research》2007,42(1P1):219-238
Objective. This paper analyzes whether the rise in managed care during the 1990s caused the increase in hospital concentration.
Data Sources. We assemble data from the American Hospital Association, InterStudy and government censuses from 1990 to 2000.
Study Design. We employ linear regression analyses on long differenced data to estimate the impact of managed care penetration on hospital consolidation. Instrumental variable analogs of these regressions are also analyzed to control for potential endogeneity.
Data Collection. All data are from secondary sources merged at the level of the Health Care Services Area.
Principle Findings. In 1990, the mean population-weighted hospital Herfindahl–Hirschman index (HHI) in a Health Services Area was .19. By 2000, the HHI had risen to .26. Most of this increase in hospital concentration is due to hospital consolidation. Over the same time frame HMO penetration increased three fold. However, our regression analysis strongly implies that the rise of managed care did not cause the hospital consolidation wave. This finding is robust to a number of different specifications. 相似文献
Data Sources. We assemble data from the American Hospital Association, InterStudy and government censuses from 1990 to 2000.
Study Design. We employ linear regression analyses on long differenced data to estimate the impact of managed care penetration on hospital consolidation. Instrumental variable analogs of these regressions are also analyzed to control for potential endogeneity.
Data Collection. All data are from secondary sources merged at the level of the Health Care Services Area.
Principle Findings. In 1990, the mean population-weighted hospital Herfindahl–Hirschman index (HHI) in a Health Services Area was .19. By 2000, the HHI had risen to .26. Most of this increase in hospital concentration is due to hospital consolidation. Over the same time frame HMO penetration increased three fold. However, our regression analysis strongly implies that the rise of managed care did not cause the hospital consolidation wave. This finding is robust to a number of different specifications. 相似文献
4.
Post-trial injections of norepinephrine, but not dopamine, into the amygdala produce a long-term retention deficit (amnesia) for a 1-trial footshock experience in rats. In contrast, post-trial injections of dopamine, but not norepinephrine, into the caudate produce long-term facilitation. The data provide evidence for brain region-neurotransmitter specificity which supports a multiple component hypothesis. 相似文献
5.
Consolidation therapies revisited: weekly paclitaxel 总被引:1,自引:0,他引:1
S. Pecorelli F. Odicino & G. Favalli 《International journal of gynecological cancer》2003,13(S2):208-211
6.
Talavera JO Wacher NH Laredo F López A Martínez V González J Lifshitz A Feinstein AR 《Archives of medical research》2000,31(6):576-584
BACKGROUND: When a CT scan is not available, an early accurate clinical diagnosis of ischemic stroke is essential to initiate prompt therapy. Our objective was to construct a clinical index that is easy to use when stroke patients are first evaluated at the hospital, to identify those who probably are experiencing an acute ischemic episode. The study was conducted at a university-affiliated medical referral center and two community general hospitals in Mexico. METHODS: Clinical records were reviewed for 801 patients with sudden onset of a focal or global neurologic dysfunction, presumably of vascular origin lasting more than 24 h. Eligibility criteria for this study were admission to the hospital within the first 24 h after symptomatic onset, CT scan diagnosis between 24 and 72 h, and age >45 years. Ischemic stroke included cases of arterial brain infarction, while nonischemic stroke included subarachnoid or intraparenchymatous hemorrhage, mass lesion, venous infarction, and in cases without a CT scan evidence that could explain the clinical manifestations. Data excerpted for analysis were age, sex, history of diabetes mellitus or previous stroke/transient ischemic attack (TIA), time of onset of symptoms, presence of headache, vomiting, neck stiffness, hemiplegia, leukocytosis or atrial fibrillation, diastolic blood pressure, and Glasgow coma scale (GCS) rating. Two multivariable analyses were used: 1) step-wise multiple logistic regression (SMLR), and 2) conjunctive consolidation (CC). RESULTS: After appropriate exclusions, the study proceeded with 83 ischemic and 42 nonischemic stroke patients. With SMLR, six variables were selected as predictive for ischemic stroke, including neck stiffness, diastolic blood pressure, previous history of stroke/TIA, hemiplegia, GCS, and atrial fibrillation. An appropriate sum of weighted ratings had a positive predictive value (PPV) of 100% for ischemic stroke. With consolidated categories, the PPV was 97% when patients had the following: no neck stiffness; no atrial fibrillation but history of stroke/TIA and GCS > or =12, or no neck stiffness but atrial fibrillation. CONCLUSIONS: Among patients with acute stroke, clinical data can be used to identify a group with a high probability of ischemic stroke. There are slightly different results between both methods; while SMLR includes the four variables selected by CC, the latter included neither diastolic blood pressure nor hemiplegia/hemiparesia. However, CC results seem easier to understand and interpret than with SMLR. 相似文献
7.
A. Debby T. Levy† H. Hayat‡ Y. Brenner‡ M. Glezerman & J. Menczer† 《International journal of gynecological cancer》2004,14(5):794-798
The value of consolidation therapy in advanced epithelial ovarian carcinoma patients is controversial. The aim of the present study was to assess the long-term survival of patients with a pathologically confirmed complete remission who had consolidation by single-dose, whole-abdominopelvic radiotherapy. Of 96 histologically confirmed stage II-IV epithelial ovarian carcinoma patients who underwent cytoreductive surgery followed by high-dose, platin-based chemotherapy, 57 were in complete clinical remission at the end of therapy and 50 underwent a second-look laparotomy. The study group comprises 32 consecutive patients who had no pathological evidence of disease and who received 800 cGy single-dose, whole-abdominal radiotherapy by an 8 MEV linear accelerator in a single fraction. The absolute 5-year survival and the actuarial 10-year survival were 78.7 and 63.3%, respectively. The survival was significantly better in patients who had < or =2 cm residual disease at the completion of the original operation. No severe postradiation complications were encountered. Mild complications were seen in three (9.4%) patients. Our data indicate a favorable long-term survival of patients with a negative second-look laparotomy who had consolidation with single-dose, whole-abdominal radiotherapy. These results seem to suggest that a collaborative, prospective, randomized multiarm study is indicated to solve the controversial issue of consolidation therapy. 相似文献
8.
9.
Morten Tulstrup Thomas L. Frandsen Jonas Abrahamsson Bendik Lund Kim Vettenranta Olafur Gisli Jonsson Hanne Vibeke Hansen Marquart Birgitte Klug Albertsen Mats Heyman Kjeld Schmiegelow On behalf of the Nordic Society of Paediatric Haematology Oncology 《European journal of haematology》2018,100(1):53-60
Objectives
This randomized controlled trial tested the hypothesis that children with non‐high‐risk acute lymphoblastic leukemia could benefit from individualized 6‐mercaptopurine increments during consolidation therapy (NCT00816049). Primary and secondary end points were end of consolidation minimal residual disease (MRD) positivity and event‐free survival.Methods
392 patients were randomized to experimental and 396 to standard therapy. Patients allocated to standard therapy received oral 6‐mercaptopurine (25 mg/m2/day) from days 30 to 85, while the experimental arm received stepwise increments of additional 25 mg/m2/day beginning on days 50 and/or 71 unless dose‐limiting myelosuppression had occurred.Results
In the experimental arm, 166 patients (42%) received one dose increment, and 62 (16%) received two. Fifty‐seven of 387 (15%) patients in the experimental arm were MRD positive at end of consolidation vs 77 of 389 (20%) in the control arm (P = .08). Five‐year probability of event‐free survival was 0.89 (95% CI: 0.85‐0.93) in the experimental arm vs 0.93 (0.90‐0.96) in the control arm (P = .13). The median accumulated length of 6‐mercaptopurine treatment interruptions was 7 (IQR 2‐12) in the experimental arm vs 4 (IQR 0‐10) in the control arm (P = .002).Conclusion
This study found no benefit from individualized 6‐mercaptopurine increments compared to standard therapy. 相似文献10.
《Journal of the American College of Radiology》2021,18(4):580-589
PurposeTo assess recent trends and characteristics in radiologist-practice separation across the United States.MethodsUsing the Medicare Physician Compare and Medicare Physician and Other Supplier Public Use File data sets, we linked all radiologists to associated group practices annually between 2014 and 2018 and assessed radiologist-practice separation over a variety of physician and group characteristics. Multivariate logistic regression modeling was used to estimate the likelihood of radiologist-practice separation.ResultsOf 25,228 unique radiologists associated with 4,381 unique group practices, 41.1% separated from at least one group practice between 2014 and 2018, and annual separation rates increased 38.4% over time (13.8% from 2014 to 2015 to 19.2% from 2017 to 2018). Radiologist-practice separation rates ranged from 57.4% in Utah to 26.3% in Virginia. Separation rates were 42.8% for general radiologists versus 38.2% for subspecialty radiologists. Among subspecialists, separation rates ranged from 43.0% for breast imagers to 33.5% for cardiothoracic radiologists. Early career status (odds ratio [OR] = 1.286) and late (OR = 1.554) career status were both independent positive predictors of radiologist-practice separation (both P < .001). Larger practice size (OR = 0.795), radiology-only (versus multispecialty) group (OR = 0.468), academic (versus nonacademic) practice (OR = 0.709), and abdominal (OR = 0.820), musculoskeletal (OR = 0.659), and neuroradiology (OR = 0.895) subspecialization were independent negative predictors (all P < .05).ConclusionsWith over 40% of radiologists separating from at least one practice in recent years, the US radiologist workforce is highly and increasingly mobile. Because reasons for separation (eg, resignation, practice acquisition) cannot be assessed using administrative data, further attention is warranted given the manifold financial, operational, and patient care implications. 相似文献