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1.
alpha-Particle-emitting radionuclides, such as (211)At, with a 7.2-h half-life, may be optimally suited for the molecularly targeted radiotherapy of strategically sensitive tumor sites, such as those in the central nervous system. Because of the much shorter range and more potent cytotoxicity of alpha-particles than of beta-particles, (211)At-labeled agents may be ideal for the eradication of tumor cells remaining after surgical debulking of malignant brain tumors. The main goal of this study was to investigate the feasibility and safety of this approach in patients with recurrent malignant brain tumors. METHODS: Chimeric antitenascin monoclonal antibody 81C6 (ch81C6) (10 mg) was labeled with 71-347 MBq of (211)At by use of N-succinimidyl 3-[(211)At]astatobenzoate. Eighteen patients were treated with (211)At-labeled ch81C6 ((211)At-ch81C6) administered into a surgically created resection cavity (SCRC) and then with salvage chemotherapy. Serial gamma-camera imaging and blood sampling over 24 h were performed. RESULTS: A total of 96.7% +/- 3.6% (mean +/- SD) of (211)At decays occurred in the SCRC, and the mean blood-pool percentage injected dose was < or = 0.3. No patient experienced dose-limiting toxicity, and the maximum tolerated dose was not identified. Six patients experienced grade 2 neurotoxicity within 6 wk of (211)At-ch81C6 administration; this neurotoxicity resolved fully in all but 1 patient. No toxicities of grade 3 or higher were attributable to the treatment. No patient required repeat surgery for radionecrosis. The median survival times for all patients, those with glioblastoma multiforme, and those with anaplastic astrocytoma or oligodendroglioma were 54, 52, and 116 wk, respectively. CONCLUSION: This study provides proof of concept for regional targeted radiotherapy with (211)At-labeled molecules in oncology. Specifically, the regional administration of (211)At-ch81C6 is feasible, safe, and associated with a promising antitumor benefit in patients with malignant central nervous system tumors.  相似文献   
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This article reviews the pertinent anatomy of each body system involved in the assessment of the head and neck (including the eyes, ears, nose, and throat) and describes the basic elements of the comprehensive health assessment. Frequently encountered chief complaints are discussed. Aspects of the health assessment that will assist the primary care provider in making a differential diagnosis and determining the need for referral are presented. This article is the first of two articles on this topic; the subsequent article will address primary care management of common conditions of the head and neck.  相似文献   
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Background: Mice immunized with murine mammary carcinoma cells genetically engineered to secrete interleukin-2 (IL-2) are rendered resistant to subsequent challenge with unmodified tumor cells, and in the case of mice bearing established tumors, the rate of development of pulmonary metastases is reduced. Despite these encouraging animal results, little is known about the induction of antitumor immunity by IL-2 gene transfer in human breast cancer. Methods: Adenovirally mediated IL-2 gene transfer was performed in 12 tumor fragment cultures established from seven primary breast cancers. Autologous tumor infiltrating lymphocytes (TILs) or peripheral blood mononuclear cells (PBMCs) were cocultured with transduced tumor fragments, and changes in phenotype and cytotoxicity were measured. Results: IL-2 was never detectable in the untransduced cultures, but it peaked at 5.0—1,324.8 ng/ml in the transduced cultures. Lymphocyte counts declined in all untransduced cultures, but they increased two- to sevenfold in four transduced cultures. CD4:CD8 ratios decreased from a mean of 2.11 at baseline to 1.27 after stimulation in coculture (p=0.03). Expansion of lymphocytes expressing the natural killer cell phenotype (CD3CD56+) occurred in only one culture, but the CD3+CD56+ population increased in four of six cultures. Lymphocytes from four of 10 cocultures generated significant cytotoxicity against allogeneic breast cancer cells. Induction of cytotoxicity correlated with expansion of the CD3+CD56+ phenotype (R2=0.805, p=0.02). Conclusions: IL-2 gene expression by human breast cancer causes expansion of CD3+CD56+ cytotoxic lymphocytes. This phenotype is consistent with that of a non-major histocompatibility complex (MHC)-restricted cytokine induced killer cell population previously described. Opinions, interpretations, conclusions and recommendations are those of the author and are not necessarily endorsed by the U.S. Army. Presented at the 49th Annual Cancer Symposium of The Society of Surgical Oncology, Atlanta, Georgia, March 21–24, 1996.  相似文献   
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INTRODUCTION: Health care workers have long been recognized as having a high risk of work-related assault. In response to a growing threat of violence in hospitals, California implemented the Hospital Security Act (AB508) in 1993. This study compares surveys of emergency nurses before and after implementation of AB508. METHODS: In 1990, the CAL/ENA surveyed emergency departments in California to enumerate violent events and describe security programs. Using the CAL/ENA membership directory, hospitals were resurveyed in 2000 to identify changes from the original survey. Surveys were mailed to the ED nurse manager or equivalent. Survey responses were anonymous. RESULTS: Most hospitals reported fewer violent episodes after the implementation of AB508. However, 32% of hospitals reported that 5 or more verbal threats occurred monthly, and 5% reported that 5 or more violent injuries occurred monthly. Overall, hospitals reported improvements in security programs. The most notable increase was in employee training, which rose from 34% to 95.6% of reporting hospitals. However, almost a quarter of hospitals reported not having general violence prevention policies, and many believed that security personnel were inadequate. DISCUSSION: Although results reported here cannot be directly attributed to AB508, the increase in security program components suggests that hospitals are responding positively to reduce violence. The high prevalence of threats and violent events reported indicates a persistent risk of violence against health care workers.  相似文献   
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ISSUE: Inadequate pain management is a serious public health problem that affects a wide cross-section of Americans. Patients are often denied sufficient medication, because physicians lack training and fear scrutiny from federal and state regulatory agencies. In addition, even the state-financed system of care, Medicaid, has been increasingly denying payment for the best treatment for pain management. These factors are complicated by physician bias about various subgroups and poor physician-patient communication. Comprehensive patient assessment plays a crucial role in determining appropriate treatment and identifying potential abuse problems. Physicians must routinely document medications analgesic effects and screen for potential ill effects and drug abuse. OBJECTIVE: To examine the prevalence of the undertreatment of pain, particularly among African Americans, and to recommend relevant proactive policy and practice changes to aid in eliminating this health problem. CONSENSUS PROCESS: In July 2002, the NMA convened the "Managing Pain: The Challenge in Underserved Populations: Appropriate Use versus Abuse and Diversion" Consensus Meeting in Washington, DC. The country's most renowned experts in the area of pain management and substance abuse reviewed substantial information regarding pain management and substance abuse including the following: --A draft summary paper on pain management and substance abuse that served as briefing material for consensus members; --Annotated bibliographies; --Articles on pain management and substance abuse; and --Key presentations on pain management and substance abuse.  相似文献   
7.
We have investigated the lipid A of Francisella tularensis subsp. holarctica strain 1547-57, a type B strain, by using matrix-assisted laser desorption ionization-time-of-flight mass spectrometry, nanoelectrospray quadrupole ion-trap mass spectrometry, and chemical methods. In accordance with the previously published structures of the lipid A from F. tularensis live vaccine strain (LVS) (ATCC 29684) (E. Vinogradov et al., Eur. J. Biochem. 269:6112-6118, 2002), all of the major lipid A forms from strain 1547-57 were tetraacylated. As in the LVS strain, the major fatty acids detected in the F. tularensis 1547-57 lipid A sample included 3-hydroxyoctadecanoic acid, 3-hydroxyhexadecanoic acid, hexadecanoic acid, and tetradecanoic acid. However, several of the lipid A components present in strain 1547-57 were of higher molecular weight than the previously published structures. A major component with an M(r) of 1,666 was found to contain three C(18:0)(3-OH) fatty acids, one C(16:0) fatty acid, one phosphate group, and one 161-Da moiety. This 161-Da moiety could be removed from the lipid A by treatment with aqueous hydrofluoric acid and was identified as galactosamine following peracetylation and analysis by gas chromatography-mass spectrometry. Detailed investigations of the M(r)-1,666 species by ion-trap mass spectrometry with multiple stages of fragmentation suggested that the galactosamine-1-phosphate was linked to the reducing terminus of the lipid A. Similar to the modification of lipid A with arabinosamine, lipopolysaccharide species from F. tularensis containing a phosphate-linked galactosamine could potentially influence its intracellular survival by conferring resistance to antimicrobial peptides.  相似文献   
8.
A new technique for the quantitative estimation of glycolytic and respiratory enzyme activity in intact and unfixed bone marrow and peripheral blood cells is described. The method gives a two- to three-fold increase in demonstrable enzyme activity per cell compared with existing techniques using fixed marrow film preparations, and is particularly applicable to the study of relatively fragile cells such as the leukaemic lymphoblast.  相似文献   
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