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21.
Smith-Lemli-Opitz syndrome (RSH/SLOS) is an autosomal recessive, malformation syndrome caused by mutations in the 3beta-hydroxysterol delta7-reductase gene (DHCR7). DHCR7 catalyzes the reduction of 7-dehydrocholesterol (7DHC) to cholesterol. We report the mutation analysis and determination of residual cholesterol synthesis in 47 SLOS patients, and the effects of treatment of SLOS skin fibroblasts with simvastatin. Using deuterium labeling we have quantified the amount of synthesized cholesterol and 7DHC in homozygote, heterozygote, and control fibroblast cell lines. In SLOS fibroblasts, the fraction of synthesized cholesterol to total sterol synthesis ranged from undetectable to over 50%. This establishes that different mutant alleles encode enzymes with varying degrees of residual activity. There was a correlation between increased phenotypic severity and decreased residual cholesterol synthesis (r(2)=0.45, p<0.0001). Simvastatin treatment of SLOS fibroblasts with residual DHCR7 enzymatic activity decreased 7DHC levels and increased cholesterol synthesis. This increase in cholesterol synthesis is due to increased expression of a mutant allele with residual function. Determination of residual enzymatic activity for specific DHCR7 mutant alleles will help in understanding the processes underlying the broad phenotypic spectrum found in this disorder and will be useful in identifying patients who may benefit from simvastatin therapy.  相似文献   
22.
The UTX gene escapes X inactivation in mice and humans   总被引:7,自引:3,他引:7  
We recently have identified a ubiquitously transcribed mouse Y chromosome gene, Uty , which encodes a tetratricopeptide repeat (TPR) protein. A peptide derived from the UTY protein confers H-Y antigenicity on male cells. Here we report the characterization of a widely transcribed X-linked homologue of Uty , called Utx , which maps to the proximal region of the mouse X chromosome and which detects a human X-linked homologue at Xp11.2. Given that Uty is ubiquitously transcribed, we assayed for Utx expression from the inactive X chromosome (Xi) in mice and found that Utx escapes X chromosome inactivation. Only Smcx and the pseudoautosomal Sts gene on the mouse X chromosome have been reported previously to escape inactivation. The human UTX gene was also found to be expressed from Xi. We discuss the significance of these data for our understanding of dosage compensation of X-Y homologous genes in humans and mice.   相似文献   
23.
The self-perceptions of children with attention-deficit/hyperactivity disorder (ADHD; n = 487) were compared with those of children in a local normative comparison group (n = 287), relative to teacher- and parent-rated perceptions of their competence. Children were participants in the ongoing follow-up portion of the Multimodal Treatment Study of Children with ADHD. Children with ADHD were much more likely than comparison children to overestimate their competence relative to adult report, regardless of who was used as the criterion rater (teacher, mother, or father). Examination by comorbidity subgroups revealed that children with ADHD inflated their self-perceptions the most in domains of greatest deficit. Gender effects also are reported.  相似文献   
24.
L1 is a neural cell adhesion molecule mainly involved in axon guidance and neuronal migration during brain development. Mutations in the human L1 gene give rise to a complex clinical picture, with mental retardation, neurologic abnormalities and a variable degree of hydrocephalus. Recently, a transgenic mouse model with a targeted null mutation in the L1 gene was generated. These knockout (KO) mice show hypoplasia of the corticospinal tract. Here we have performed further studies of these KO mice including magnetic resonance imaging of the brain, neuropathological analysis and behavioral testing. The ventricular system was shown to be abnormal with dilatation of the lateral ventricles and the 4th ventricle, and an altered shape of the Sylvius aqueduct. Additionally, the cerebellar vermis of the KO mice is hypoplastic. Their exploratory behavior is characterized by stereotype peripheral circling reminiscent of that of rodents with induced cerebellar lesions.   相似文献   
25.
Lung carcinoma remains one of the most frequent and aggressive human neoplasms. Fortunately, in the last decades, the increasing knowledge of the molecular mechanisms leading to cancer development has allowed the use of targeted therapies with improvement of prognosis in many patients. Clinical management has also changed after the introduction of endobronchialultrasonographic bronchoscopy that allows a conservative staging of lung tumors, avoiding the need of mediastinoscopy for lymph node staging. Lung pathologists and cytopathologists are facing the challenge of giving the more comprehensive prognostic and predictive information with ever smaller tissue or cytological samples. The aim of this review is to summarize the molecular testing for non-small cell lung carcinoma and how pathologists can contribute to the patient's outcome with a conscious management of biological samples.  相似文献   
26.
Journal of Prevention - Social and Emotional Learning (SEL) programs seek to enhance social and emotional competencies in children, including self-awareness, self-management, social awareness,...  相似文献   
27.

Objectives

To evaluate the efficacy of combined finasteride and flutamide therapy in men with advanced prostate cancer by determining (1 ) the short-term tolerability of finasteride monotherapy and its effect on serum prostate-specific antigen (PSA) and hormone (testosterone, dihydrotestosterone) levels, and (2) the effects of the addition of flutamide on tolerability and on serum PSA and hormone levels.

Methods

Thirteen hormone-naive men with advanced prostate cancer (4 with Stage D2, 1 with Stage D1, 1 with Stage DO, 7 with rising PSA levels after radical prostatectomy [n = 2]or definitive radiation therapy [n = 5]) were initially treated with 5 mg finasteride daily. Flutamide (250 mg three times a day) was added after serum PSA levels stabilized.

Results

Finasteride alone (median 5 weeks) had no significant effect on serum PSA levels (P>0.05). Combined finasteride and flutamide resulted in a mean 91% reduction in serum PSA levels, with 85% of men achieving a nadir serum PSA level of less than 4.0 ng/mL and 46% achieving undetectable levels (0.2 ng/mL or less). Finasteride alone had no significant effect on serum testosterone levels (P>0.05) but did result in a mean 74% reduction in serum dihydrotestosterone levels. Combined finasteride and flutamide resulted in a mean 56% increase in serum testosterone levels but had no additional effect on serum dihydrotestosterone levels (P>0.05). Side effects occurred in 85% (gynecomastia or breast tenderness in 62% [8 of 13]and diarrhea in 23% [3 of 13]) of men on combined therapy. Potency was preserved in 66%. Combined finasteride and flutamide therapy was withdrawn from 15% (2 of 13) because of flutamide-induced diarrhea and from 23% (3 of 13) because of disease progression. All remaining patients (8 of 13) have serum PSA levels below 4.0 ng/mL and 4 of these 8 have undetectable levels. These men have received combined finasteride and flutamide for a median 11 months (range 6 to 19).

Conclusions

Finasteride monotherapy is inadequate therapy for advanced prostate cancer, but combined finasteride and flutamide may be a reasonable alternative for men with advanced prostate cancer who refuse conventional hormone therapy.  相似文献   
28.
Over a follow-up period of 6 years, 4 out of 31 live related renal allograft recipients (12.9%) developed azathioprine induced bone marrow suppression. Presentation in 3 patients was with fever and 2 patients also had associated graft dysfunction. All patients had leucopenia, 2 patients in addition had anaemia and one patient had pancytopenia. Bone marrow suppression developed 9.6 months (3.5-16.0 months) following transplantation and recovery followed over a period of 30 (18-49 days) days after withdrawal of the drug. One patient succumbed during the phase of bicytopenia.KEY WORDS: Azathioprine, Bone marrow suppression, Kidney transplantation  相似文献   
29.
The use of a multimedia computer-based patient record (CPR) within ambulatory care is a topic that has not achieved widespread understanding or acceptance. However, if the topic is divided into its parts, multimedia and computer-based patient record, it reflects both highly recognizable and desirable goals that most health care organizations are undertaking. Multimedia technology is quickly maturing. In addition, the goal of attaining a CPR is of primary interest to most health care organizations. It is inevitable that these two technologies will eventually become synergistic. This article presents the case for a multimedia ambulatory CPR and describes one example of this happy marriage.  相似文献   
30.
    
Résumé Notre étude porte sur les toxicomanes en difficulté du fait de leur consommation de drogue dans le canton de Vaud; elle s'étend de 1974 à 1978 et bénéficie du concours de la police cantonale, d'hôpitaux, d'instituts médico-sociaux et de centres sociaux. L'observation porte sur 1519 cas de consommateurs de drogues dures, 1993 consommateurs de drogues douces et 186 cas d'abus chronique sévère de médicaments seuls.Pour les drogues dures, l'effectif annuel des cas nouveaux âgés de moins de 20 ans culmine en 1976. Quant aux «anciens» toxicomanes, leur effectif ne cesse d'augmenter. L'héroïne est la drogue la plus utilisée; elle est associée dans un quart des cas aux amphétamines, elles-mêmes remplacées par la cocaïne dès 1978. Les premières cohortes importantes d'héroïnomanes dans le canton de Vaud auront 28 à 30 ans en 1980.Pour les drogues douces, les effectifs enregistrés diminuent légèrement au cours des cinq ans d'observation. La participation des jeunes est particulièrement élevée, les anciens consommateurs sont beaucoup moins nombreux. L'usage de drogues dures ou douces concerne deux hommes pour une femme.L'abus sévère de médicaments touche un petit groupe plus âgé à prédominance féminine, qui varie peu au cours des cinq ans d'observation.
Drug-addiction in the canton of Vaud, 1974–8
Summary Our study is concerned with drug-addicts in the Swiss canton of Vaud who are in difficulties as a result of their drug consumption. The survey covers the period from 1974 until 1978, and was carried out with the assistance of the cantonal police, hospitals, sociomedical institutes, and social assistance centres. We investigated:1519 cases of consumers of hard drugs (opiates, amphetamines, and cocaine)1993 consumers of soft drugs (haschisch and hallucinogens)186 cases of serious chronic abuse of medicaments only, which were accidentally discovered by our information systemWith hard drugs, the annual number of new cases in the age group below 20 shows a peak in 1976, and remains so far at a level one third below. As far as older subjects are concerned, mostly old drug-addicts, the total number in the age group 20–29 continues to increase year after year. In exchange, in the age group 30 and older, the level of addiction to hard drugs remains constant and low. Heroin is drug number one, and is in 25 % of the cases associated with amphetamines, which are replaced by cocaine since 1977–8. It should be noted that the first bigger group of heroin-addicts in the canton of Vaud will be 28–30 years old in 1980. By the end of 1978, the total number of subjects addicted to hard drugs might amount to at least 830.The total number of subjects recorded as addicted to soft drugs decreased slightly in the course of the five years under observation. The percentage of young addicts is particularly high, while there are much fewer old consumers. Every third addict to hard or soft drugs is a woman.Abuse of medicaments is limited to a small group, which is older, consists predominantly of women, and varies little in the course of the five years under observation.The collected material is discussed in the light of data published in the foreign literature.

Drogenabhängigkeit im Kanton Waadt, 1974–1978
Zusammenfassung Unsere Untersuchung bezieht sich auf die Drogenabhängigen, welche zwischen 1974 und 1978 im Kanton Waadt durch ihren Drogenkonsum in Schwierigkeiten gekommen sind. Sie wurde ermöglicht durch die Mitwirkung der Kantonspolizei, von Spitälern, sozialmedizinischen Instituten und sozialen Einrichtungen. Folgende Gruppen von Drogenabhängigen wurden erfasst:1519 Konsumenten von harten Drogen (Opiate, Amphetamine, Kokain)1993 Konsumenten von weichen Drogen (Haschisch, Halluzinogene)186 Fälle von schwerem chronischem Medikamentenmissbrauch, welche zufällig durch unser Informationsnetz erfasst wurdenBei den harten Drogen erreicht die Anzahl der jährlichen neuen Fälle unter 20 Jahren 1976 den Höhepunkt und hält sich seither um einen Drittel unter diesem Niveau. Die Älteren sind meist schon Langzeitkonsumenten. Die Anzahl der 20- bis 29jährigen nimmt mit den Jahren ständig zu, die der 30jährigen und älteren bleibt gering und konstant. Heroin ist die meistgebrauchte harte Droge; in einem Viertel der Fälle wird es kombiniert mit Amphetaminen; diese werden seit 1977/78 durch Kokain ersetzt. Die ersten bedeutenden Kohorten von Heroinabhängigen im Kanton Waadt werden 1980 28 bis 30 Jahre alt sein. Die Gesamtzahl der Konsumenten von harten Drogen im Kanton Waadt dürfte Ende 1978 bei mindestens 830 liegen.Bei den weichen Drogen nimmt die Anzahl der registrierten Fälle im Laufe der fünf Jahre etwas ab. Der Anteil der Jungen ist hier besonders hoch. Langzeitkonsumenten sind hier weniger zahlreich. Der Konsum von harten und weichen Drogen betrifft doppelt so viele Männer wie Frauen.Schwerer Medikamentenmissbrauch wurde vor allem bei über 30jährigen angetroffen, vorwiegend bei Frauen. Im Laufe der fünf Jahre hat sich hier kaum etwas geändert.Die Angaben werden im Lichte der ausländischen Literatur diskutiert.
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