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91.
OBJECTIVES: This report presents final 2001 data on the 10 leading causes of death in the United States by age, race, sex, and Hispanic origin. Leading causes of infant, neonatal, and postneonatal death are also presented. This report supplements the annual report of final mortality statistics. METHODS: Data in this report are based on information from all death certificates filed in the 50 States and the District of Columbia in 2001. Causes of death classified by the International Classification of Diseases, Tenth Revision are ranked according to the number of deaths assigned to rankable causes. RESULTS: In 2001, the 10 leading causes of death were (in rank order) Diseases of heart; Malignant neoplasms; Cerebrovascular diseases; Chronic lower respiratory diseases; Accidents (unintentional injuries); Diabetes mellitus; Influenza and pneumonia; Alzheimer's disease; Nephritis, nephrotic syndrome and nephrosis; and Septicemia and accounted for nearly 80 percent of all deaths occurring in the United States. Differences in the rankings are evident by age, sex, race, and Hispanic origin. Leading causes of infant death for 2001 were (in rank order) Congenital malformations, deformations and chromosomal abnormalities; Disorders related to short gestation and low birth weight, not elsewhere classified; Sudden infant death syndrome; Newborn affected by maternal complications of pregnancy; Newborn affected by complications of placenta, cord and membranes; Respiratory distress of newborn; Accidents (unintentional injuries); Bacterial sepsis of newborn; Diseases of the circulatory system; and Intrauterine hypoxia and birth asphyxia. Important variation in the leading causes of infant death is noted for the neonatal and postneonatal periods.  相似文献   
92.
CT of fatty thoracic masses.   总被引:2,自引:0,他引:2  
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93.
1. The effects of formoterol, a beta 2-adrenoceptor agonist, on plasma protein exudation and microvascular permeability induced by topical, i.e. applied onto the tracheal mucosal surface, bradykinin (10 nmol; 20 microM, 5 min, 0.1 ml min-1) were studied in a perfused segment of trachea prepared in situ in anaesthetized rats. 2. Bradykinin increased the amount of plasma (fluorimetric assay for protein) in the perfusate (response; 10.98 +/- 0.357 microliters, n = 69; total increase in plasma over basal during 45 min after start of bradykinin application) and 2 responses at a 90 min interval were reproducible. Carbon labelling was seen in tracheal sections from animals that received i.v. colloidal carbon, indicating that bradykinin caused tracheal microvessels to leak (increase in microvascular permeability). 3. Five minutes after topical formoterol, 5 or 30 nmol (10 or 60 microM perfused for 5 min), the bradykinin response was significantly reduced. The effects of formoterol were not dose-related, i.e. were maximal at 5 nmol. The bradykinin response was at control levels 30 min after 5 nmol formoterol. After 30 nmol formoterol, the response was still reduced 120 min later. The bradykinin response was significantly reduced 60 min after systemic formoterol (i.p., 0.029 to 870 nmol kg-1) and, for 290 nmol kg-1 i.p. formoterol, this reduction was shown to last at least 150 min.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
94.
A model is proposed for evaluation of osmolality of multicomponent formulas composed of modular ingredients. Nonlinear curve-fitting techniques applied to empirical data result in prediction of the osmolality of ingredients for any concentration desired. Osmolality of a multicomponent formula can be obtained by adding osmolalities of ingredients. Data handling is made possible by the use of simple microcomputer programs. The model is tested with products available for construction of amino acid-restricted diets.  相似文献   
95.
We describe 5 patients who presented with an acute cauda equina syndrome, which we believe was due to infarction of the conus medullaris. In 3 patients, the onset was spontaneous, and in 2 patients it was secondary to temporary occlusion of the distal aorta during medical manipulation. Pain in the buttocks and posterior thighs was a prominent initial symptom in the 3 patients with unprovoked attacks. The main clinical features were profound impairment of bowel and bladder function and of perianal and perineal sensation (S3 to S5 segments). There was sensory and motor impairment in the legs of variable extent, most marked in the S1 and S2 segments, but extending as high as L4 in 2 patients. In 1 patient, ischemic changes in the conus medullaris were confirmed post mortem. Ischemia confined to the caudal tip of the spinal cord is rare, and an underlying anomaly of the pattern of arterial supply is a likely predisposing factor. Four patients had partial return of function over a period of weeks.  相似文献   
96.
The search for a hormonal marker in breast cancer has centered on estrogens and their metabolites. However, direct measurements of total amounts of these steroids have shown no convincing or consistent differences between normal women and women with breast cancer. The purpose of this study was to measure the percentages of non-protein-bound estradiol (%NPBE) and of estradiol bound to albumin (%ABE) and the levels of sex hormone-binding globulin (SHBG) both in women with breast cancer and in those free of disease. Serum was collected and analyzed within 2 weeks, using an isodialysis method. The mean %NPBE and %ABE were significantly higher in 32 women with breast cancer (1.73 and 64.0%, respectively) than in 32 matched disease-free women (1.43 and 48.6%, respectively) (P less than 0.001). No significant difference was observed in the levels of plasma albumin when the above matched groups were compared. However, plasma levels of SHBG were significantly lower in the women with breast cancer than in either the control population or matched controls. In this finding we differ from previous studies which reported no significant differences in the mean plasma levels of SHBG. In our study, the increased %NPBE and %ABE in some patients with breast cancer may be related to a lower level of plasma SHBG; other factors, too, may affect the distribution of estradiol. Our results support the hypothesis than an increase in %NPBE and %ABE or both may indicate an increased risk of breast cancer.  相似文献   
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99.
The essential amino acid, tryptophan, has been shown to lower blood pressure in rats when administered orally or intravenously. In order to potentially enhance this action, a brain-targeting chemical delivery system (CDS) approach was applied to this compound. The CDS is based on a dihydropyridine----pyridinium ion redox system, chemically analogous to the naturally occurring NADH----NAD+ system. The dihydropyridine moiety containing carrier is chemically attached to the amino group by an amide-type bonding while the carboxylic acid functionality is esterified to various alcohols. Physicochemical studies of the new derivatives were performed. The determined chromatographic Rm values indicate an increased lipophilicity for the CDSs compared to the parent compound. Oxidation stability studies performed on selected compounds using a ferricyanide-mediated method showed that the CDSs are oxidized to the respective quaternary salt forms. Activity studies performed in deoxycorticosterone acetate induced hypertensive rats, demonstrated that the delivery system for tryptophan reduced blood pressure more efficiently for a longer time than did the parent compound.  相似文献   
100.
Federal regulations prescribe distinct protections for children participating in research studies. Procedures for collecting tissue specimens from children solely for research purposes must pose no more than a minor increase over minimum risk, thereby limiting the approvable correlative biologic studies to evaluate molecularly targeted agents in children with cancer. Ethical issues arise when approvable correlative studies are a mandatory component of an early-phase pediatric clinical trial of new anticancer agents. The National Cancer Institute Cancer Therapy Evaluation Program sponsored a workshop in 2002 to discuss tissue collection for correlative biologic studies in early-phase childhood cancer clinical studies of molecularly targeted agents. Workshop participants recommended the following: (1) tissue specimens for correlative studies should provide vital clinical and scientific results to qualify for early-phase pediatric study consideration; (2) parents should receive a realistic appraisal of the risks, requirements, and potential for benefit of phase I protocol participation; (3) investigators should clearly distinguish clinically necessary procedures from research procedures of no benefit to the child to improve correlative study informed consent; and (4) participation in correlative research studies included in clinical trials generally should be voluntary. The need to acquire important biologic data regarding new molecular agents will challenge the ingenuity of pediatric cancer researchers, necessitating the application of highly sensitive laboratory assay methods, new imaging procedures, and preclinical models of childhood cancer. Such innovative methods can allow necessary scientific information to be obtained while simultaneously respecting the protections appropriately afforded to children participating in research studies and minimizing the burden of research participation for children with cancer and their families.  相似文献   
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