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91.
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The anatomy responsible for the sonographic diagnosis of the renal “junctional parenchymal defect” and “interrenicular septum” is caused by perirenal fat along a line of incomplete fusion of two primary renal lobes. Studies using CT, MRI and cadaver observations are presented. “Oddono's sulcus” is suggested as a name for the changes in honor of the author who first described these anatomic findings. Received: 12 January 1996 Accepted: 16 January 1996  相似文献   
93.
A series of benzoylureas derived from bicycle amines were prepared and evaluated for 5-HT3 antagonist activity on the rat isolated vagus nerve. From among these compounds, those analogues which were ortho substituted by an alkoxy group on the benzoyl function were shown to be potent 5-HT3 antagonists with similar or greater potency than the standard agent ondansetron. NMR and X-ray crystallography studies showed these o-alkoxy compounds to exist as a planar, hydrogen-bonded, tricyclic ring system. In molecular modeling studies on endo-N-[[(8-methyl-8-azabicyclo[3.2.1]octan-3-yl-amino] carbonyl]-2-(cyclopropylmethoxy)benzamide (30) the central hydrogen-bonded ring was able to mimic an aromatic ring present in previously reported 5-HT3 antagonists.  相似文献   
94.
A genetic polymorphism in S-acetyl coenzyme A (AcCoA)-dependentN-acetyltransferase has been associated with a differentialrisk for certain cancers in humans. In this study, several tissuesfrom the inbred Syrian hamster with a genetically defined AcCoA-dependentN-acetyltransferase polymorphism (homozygous rapid acetylator,Bio. 87.20; homozygous slow acetylator, Bio. 82.73/H; and heterozygousacetylator, Bio. 87.20 x Bio. 82.73/H F1), were investigatedfor the relationship of arylamine N-acetyltransferase to theAcCoA-dependent metabolic activation of carcinogenic N-hydroxy(N-OH)-arylamines to bind to DNA (O-acetyltransferase). Thelevels of both 2-aminofluorene (AF) N-acetyltransferase andN-OH-AF O-acetyltransferase activity reflected the N-acetylatorgenotype in liver, intestine, kidney and lung cytosols. A significantacetylator gene—dose response for AF N-acetyltransferaseand N-OH-AF O-acetyltransferase activities was observed in liverand lung cytosols. In contrast, acetylator genotype was notconsistently expressed for the AcCoA-dependent N-acetylationof 4-aminobiphenyl (ABP), nor for the AcCoA-dependent metabolicactivation of N-OH ABP and N-OH-3,2'-dimethyl-4-aminobiphenylin these me tissue cytosols. Two peaks of acetyltransferaseactivity were partially purified by ion exchange FPLC chromatographyfrom the hepatic cytosol of both the homozygous rapid and homozygousslow acetylator hamster. In contrast to unfractionated cytosol,the isozyme(s) eluting first clearly demonstrated levels ofAcCoA-dependent arylamine N-acetyltransferase and N-OH-arylamineO-acetyltransferase activities that were consistent with N-acetylatorgenotype (polymorphic) for all substrates tested. In contrast,the slower eluting isozyme(s) in each acetylator cytosol showedlevels of AcCoA-dependent N-and O-acetyltransferase activitiesthat did not vary with N-acetylator genotype (monomorphic).The AcCoA-dependent O-acetyltransferase activity of both themonomorphic and polymorphic peaks was paraoxon resistant. Thesestudies demonstrate acetylator genotype-dependent control ofAcCoA-dependent metabolic activation of N-OH-arylamines(O-acetylation)by polymorphic isozyme(s) similar to that for AcCoA-dependentN-acetylation of arylamines in the hamster. The polymorphicgenetic control of N-OH arylamine O-acetyltransferase may bean important risk factor for arylamine-induced cancer, in thosespecies and tissues expressing appreciable levels of O-acetyltransferaseactivity.  相似文献   
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PURPOSE: To examine changes in health habits (sleep, alcohol, and exercise) and the effects of an educational intervention promoting self-care on the emotional and academic adjustment of first-year medical students. METHOD: Fifty-four medical students completed questionnaires that assessed various health habits, alcohol use, depression severity, and areas of life satisfaction at the beginning of the semester, at mid-term, and at finals. Approximately half of the students received written feedback or participated in an educational discussion group at mid-term. RESULTS: The students demonstrated significant changes in health habits, with increases in alcohol consumption and decreases in exercise and socialization. The changes in health habits were predictive of both emotional and academic adjustment, with students who decreased in positive health habits, particularly socialization, being more depressed at finals. The feedback and educational interventions influenced some sleep and exercise behaviors, but the groups did not differ in overall emotional or academic adjustment. CONCLUSIONS: First-year medical students show significant changes in health habits as they adjust to medical school. An educational intervention demonstrated promising effects in changing these patterns, but self-care needs to be further elaborated to address the specific challenges associated with acute adjustment as well as with long-term stressors.  相似文献   
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PURPOSE: In this investigation, we evaluated a population of patients with chronic orofacial pain who sought treatment at a pain center in an academic institution. These patients were evaluated with respect to 1) the frequency and types of previous oral and maxillofacial surgery procedures, 2) the frequency of previous significant misdiagnoses, and 3) the number of patients who subsequently required surgical treatment as recommended by an interdisciplinary orofacial pain team. The major goal of this investigation was to determine the role of oral and maxillofacial surgery in patients with chronic orofacial pain. Patients and Methods: The study population included patients seen at the Center for Oral, Facial and Head Pain at New York Presbyterian Hospital from January 1999 through April 2001. (120 patients; female-to-male ratio, 3:1; mean age, 49 years; average pain duration, 81 months; average number of previous specialists, 6). The patient population was evaluated by an interdisciplinary orofacial pain team and the following characteristics of this population were profiled: 1) the frequency and types of previous surgical procedures, 2) diagnoses, 3) the frequency of previous misdiagnoses, and 4) treatment recommendations made by the center team. RESULTS: There was a history of previous oral and maxillofacial surgical procedures in 38 of 120 patients (32%). Procedures performed before our evaluation included endodontics (30%), extractions (27%), apicoectomies (12%), temporomandibular joint (TMJ) surgery (6%), neurolysis (5%), orthognathic surgery (3%), and debridement of bone cavities (2%). Surgical intervention clearly exacerbated pain in 21 of 38 patients (55%) who had undergone surgery. Diagnoses included myofascial pain (50%), atypical facial neuralgia (40%), depression (30%), TMJ synovitis (14%), TMJ osteoarthritis (12%), trigeminal neuralgia (10%), and TMJ fibrosis (2%). Treatment recommendations included medications (91%), physical therapy (36%), psychiatric management (30%), trigger injections (15%), oral appliances (13%), biofeedback (13%), acupuncture (8%), surgery (4%), and Botox injections (1%) (Allergan Inc, Irvine, CA). Gross misdiagnosis leading to serious sequelae, with delay of necessary treatment, occurred in 6 of 120 patients (5%). CONCLUSIONS: Misdiagnosis and multiple failed treatments were common in these patients with chronic orofacial pain. These patients often have multiple diagnoses, requiring management by multiple disciplines. Surgery, when indicated, must be based on a specific diagnosis that is amenable to surgical therapy. However, surgical treatment was rarely indicated as a treatment for pain relief in these patients with chronic orofacial pain, and it exacerbated and perpetuated pain symptoms in some of them.  相似文献   
99.
OBJECTIVE: The purpose of this study was to evaluate a pilot occupational therapy wellness program designed to teach elders the importance of participation in meaningful social and community occupations to their quality of life. METHOD: Sixty-five older adults participated in this pilot wellness program held at each of three senior apartment complexes. Measures of health-related quality of life using the SF-36 Health Survey and frequencies of social and community participation from a program-specific intake form were completed by 39 participants before and after the 6-month program. Participants also evaluated components of the program through a satisfaction survey. RESULTS: Scores on the SF-36 Health Survey were significantly higher in vitality, social functioning, and the mental health summary scores following participation in the program. Participants reported an increased frequency of socialization and community participation with an average of 55% participating in at least three or more activities per week before the program to an average of 66% participating after the program. Participants who benefited the most attended more classes, were older, and were nondrivers. Eighty percent of those polled rated the pilot program as good or excellent. CONCLUSION: This pilot study provides additional support for prevention efforts for elders in the community. Wellness programs for seniors may be most effective if targeted to those who are older and nondrivers.  相似文献   
100.
The thymidylate synthase (TS) inhibitor ICI D1694 (N-(5-[N-(3,4-dihydro-2-methyl-4-oxoquinazolin-6-ylmethyl)-N -methylamino]-2 - thenoyl)-S-glutamic acid) is a structural analogue of the substrate N5,N10-methylenetetrahydrofolate (5,10-CH2FH4) and is currently under clinical evaluation as a treatment for cancer. The compound is shown here to be a mixed non-competitive inhibitor of TS from murine leukemia (L1210) cells when 5,10-CH2FH4 is varied. This result suggests formation of an inactive complex between TS, 5,10-CH2FH4 and the inhibitor. Thus, binding to only one of the two active sites on the TS homodimer may be sufficient to prevent catalysis fully. Treatment of L1210 cells with ICI D1694 is known to cause intracellular accumulation of the tetraglutamate derivative which is shown here to have a 60-fold higher affinity for TS. The IC50 for inhibition of L1210 cell growth is below the Ki value of ICI D1694 for L1210 TS but above that of the tetraglutamate. The formation of polyglutamates and concentration of drug inside cells, therefore, seem to be responsible for biological activity.  相似文献   
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