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Previous studies have suggested that patients with familial adenomatous polyposis (FAP) have increased faecal excretion of cholesterol but a reduction in cholesterol metabolites. It was consequently proposed that the degree of faecal cholesterol degradation could be used as a means of diagnosis. Developments in the extraction and analysis of faecal neutral sterols as well as the accurate means of diagnosing FAP by DNA analysis and indirect ophthalmoscopy has necessitated a re-examination of this proposal. Faecal neutral sterols were analysed in 10 patients with untreated FAP following a complete 5-day stool collection and compared with 9 healthy control subjects (including 4 siblings) closely matched for age and sex. The median [25 and 75, percentiles] stool wet weights were similar between the FAP (97.5 [69, 192] g · 24 h-1) and the control (116 [61.5, 137] g · 24 h-1) groups. Faecal cholesterol concentration was similar in the two groups (FAP=2.3 [1.4, 4.2]; control=3.5 [1.0, 6.0] mol · g-1 dry wt) as was the concentration of total neutral sterols not including plant sterols (FAP=17.2 [13.4, 21.0]; control=18.2 [7.4, 21.6] mol · g-1 dry wt). There were no significant differences in the proportions of cholesterol metabolised between the FAP (82.3 [74.2, 93.5]%) and control (72.1 [5.7, 81.3]%) groups. This study does not support the notion that faecal neutral sterol metabolism is uniquely different in patients with FAP.
Résumé Des études précedentes avaient suggéré que les malades avec polypose adénomateuse familiale (PAF) avaient une excrétion fécale augmentée de choléstérol mais une réduction des métabolìtes du choléstérol. On a donc proposé que les degrés de dégradation fécale du choléstérol puisse être utilisée comme moyen de diagnostic. Le développement dans l'extraction et l'analyse des stérols neutres fécaux aussi bien que des moyens appropriés de diagnostiquer la PAF par analyse du DNA et ophthalmoscopie indirecte a nécessité un ré-examen de cette proposition. Les stérols neutres fécaux, ont été analysés chez 10 patients avec une PAF non traitée après une collection complète des matières de 5 jours et comparés avec 9 sujets contrôles sains (comprenant 4 enfants de mêmes parents) étroitement appareillés pour l'âge et le sexe. Les poids moyens (25 et 75 percentiles) de selles humides étaient similaires chez les PAF (97.5 (69, 192) g · 24 h-1) et les contrôles (116 (61.5, 137) g · 24 h-1). La concentration de choléstérol fecal était similaire dans les deux groupes (PAF=2.3 (1.4, 4.2); controle=3.5 (1.0, 6.0) mol · g poids sec) de même que la concentration de stérols neutres totaux stéroïdes végétaux exclus (PAF=17.2 (13.4, 21.0); controle 18.2 (7.4, 21.6) mol · g poids sec). Il n'y avait pas de différence significative dans les proportions de choléstérol métabolisé entre les PAF (82.3 (74.2, 93.5)%) et les contrôles (72.1 (5.7, 81.3)%). Cette étude ne confirme pas la notion que le métabolisme des stérols neutres fécaux est uniquement différent chez les patients avec une PAF.
  相似文献   
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Hepatic abscess   总被引:2,自引:0,他引:2  
Hepatic abscess—amebic or pyogenic—can be diagnosed with great accuracy by either ultrasonography or computed tomographic (CT) scanning. Ultrasound is the modality of choice and will detect almost 100% of abscesses. Confirmation of a diagnosis of amebic liver abscess is made by the indirect hemagglutination test that should be positive in almost 100% of cases. Cultures of pus from the abscess and from the blood must be obtained in cases of pyogenic liver abscess. A positive culture of pus from the abscess has been achieved in 90% of cases. Ultrasound or CT guidance is utilized in aspiration of a hepatic abscess. In the treatment of an amebic liver abscess, metronidazole is the amebicide of choice. Open drainage is contraindicated. For cases that fail to respond to therapy with amebicides, closed drainage guided by CT or ultrasound is performed. Secondary bacterial infection of an amebic liver abscess is an extremely rare event. The identification and determination of the antibiotic sensitivity of organisms responsible for pyogenic liver abscess is a crucially important step. Unless a celiotomy is necessary to correct an intraabdominal process or the abscess is extremely large, the initial treatment of pyogenic liver abscess is a 2 week course of appropriate antibiotics followed by a 1 month course of oral antibiotics. The majority of pyogenic liver abscesses will respond to such treatment. If drainage of a pyogenic abscess is required, the preferable technique is with a percutaneous CT- or ultrasound-directed catheter. Open surgical drainage should be reserved for those cases in which a celiotomy is required for other purposes or for the patient who has failed a course of appropriate antibiotic therapy and closed percutaneous drainage is not feasible. The mortality for treatment of amebic liver abscess should be approximately zero and for pyogenic liver abscess should be less than 10%.
Resumen El absceso hepático—amibiano o piogénico—puede ser diagnositicado con gran precisión mediante la ultrasonografía (US) o la tomografía computadorizada (TC). La ultrasonografía es la modalidad de escogencia; détecta casí el 100% de los abscesos. La confirmación del diagnóstico de absceso amibiano del hígado se hace por la prueba de hemaglutinación indirecta, la cual debe resultar positiva en prácticamente el 100% de los casos. Cultivos del pus y de la sangre deben ser realizados en los pacientes con abscesos piógenos. Se logran cultivos positivos del pus del absceso en 90% de los casos. Se utiliza la guía ultrasonográfica o de tomografía computadorizada para la aspiración del absceso.El metronidazol es el agente amebicida de preferencia en el tratamiento del absceso amibiano del hígado. El drenaje abierto está contraindicado. En los casos en que falla la terapia con amibicidos, se realiza el drenaje cerrado guiado por US o por TC. La infección secundaria de un absceso amibiano del hígado es un fenómeno extraordinariamente raro.La identificatión y determinatión de la sensibilidad antibiótica de los microorganismos responsables del absceso piógeno representa un paso crucial en su manejo. A menos que se haga necesario realizar una laparotomía para la correción del algún proceso intraabdominal o porque el absceso es excesivamente grande, el tratamiento inicial del absceso piógeno es un ciclo de antibióticos propiados de 2 semanas, seguidos de tratamiento con antibióticos orales por un mes. La mayoría de los abscesos piógenos del hígado responde a este tipo de tratamiento. Si se requiere drenaje de un absceso piógeno, la técnica de preferencia es la punción percutánea por medio de un catéter guiado por US o TC. El drenaje quirúrgico abierto debe reservarse para aquellos casos en que la laparatomía es necesaria por razones diferentes o en que hay falla en la respuesta a un ciclo de terapia antibiótica adecuada y el drenaje percutáneo no es factible.La mortalidad en el manejo del absceso amibiano del hígado debe ser nula, y para el absceso piógeno de menos de 10%.

Résumé L'abcès hépatique amibien ou à pyogènes peut être diagnostiqué avec une grande précision soit par l'échographie, soit par la tomodensitométrie. L'échographie est la méthode de choix et détecte presque 100% des abcès. On obtient la confirmation du diagnostic d'abcès amibien par le test d'hémagglutination indirecte qui est positive dans presque 100% des cas. On doit faire des cultures de pus provenan de l'abcès et des hémocultures en cas d'abcès à pyogènes du foie. Ces cultures ont été positives dans 90% des cas. L'échographie et la tomodensitométrie aident à guider le drainage de abcès.Dans le traitement de l'abcès amibien du foie, le métronidazole est l'amibicide de choix. Le drainage à ciel ouvert est contreindiqué. Pour les cas qui ne répondent pas aux amibicides, un drainage percutané guidé par la tomodensitométrie ou l'échographie est indiqué. La surinfection d'un abcès amibien du foie est extrêmement rare.L'identification et la détermination de la sensibilité aux antibiotiques des organismes responsables de l'abcès à pyogènes est une étape extrêmement importante. A moins qu'une laparotomie soit nécessaire pour traiter une infection intraabdominale associée ou que le volume de l'abcès soit extrêmement important, le traitement initial d'un abcès à pyogènes comprend 2 semaines d'antibiotiques adaptés par voie générale suivies d'un mois d'antibiotiques par voie orale. La plupart des abcès à pyogènes répondront bien à ce traitement. Si le drainage d'un abcès à pyogènes s'avère nécessaire, la meilleure technique est percutanée avec un cathéter inséré sous contrôle tomodensitométrique ou échographique. On réservera le drainage chirurgical à ciel ouvert aux cas où une laparotomie est nécessaire pour d'autres raisons et où le malade n'a pas répondu à l'antibiothérapie adaptée et chez qui le drainage percutané est impossible à faire.La mortalité de l'abcès amibien traité devrait approcher 0% et atteindre pour l'abcès à pyogènes moins de 10%.
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Simulator radiographs taken as a record of breast radiotherapy planning often show ill defined breast tissue margins because exposure parameters are set to optimize visualization of the chest wall rather than the bulk of the breast. This creates difficulties when using simulator images as reference images in verification by comparing with either portal film or images from an electronic portal imaging device. Our aim was to improve breast images taken at simulation without changing exposure parameters that have been optimized for visualization of the chest wall. This has been achieved via an external filter to be used when taking radiographs with the treatment simulator. The filter is made of stainless steel coated with tin and is shaped to maintain acceptable imaging of the chest wall by covering only the section of field anterior to the chest wall. Radiographs of breast simulations using the filter have been accepted as satisfactory by both clinicians and radiographers. The filter is now in routine clinical use for breast and chest wall treatment simulation.  相似文献   
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OBJECTIVES: We wished to determine whether early rejection after lung transplantation as assessed by surveillance transbronchial biopsy predicts for survival. METHODS: Between 1990 and 1997, 96 consecutive patients had lung transplantation: 89 had a minimum 1-month follow-up. For 71 consecutive patients we have 1-year follow-up and for 69 patients we have the results of the first 3 biopsies. Cytomegalovirus status, bronchiolitis obliterans prevalence, and use of total lymphoid irradiation are noted. Biopsies were done at 1 week and 1, 3, and 6 months. Standard immunosuppression consisted of induction antilymphocyte globulin and high-dose methylprednisolone induction for 1 week and standard maintenance triple therapy. Acute rejection treatment was with pulse methylprednisolone. Bronchiolitis obliterans syndrome was treated with total lymphoid irradiation and a change to tacrolimus and mycophenolate. Blinded grading using International Society for Heart and Lung Transplantation classification was done retrospectively. RESULTS: Survival at 1 month and 1, 2, and 3 years for the 96-patient cohort with 1-year follow-up was 93%, 74%, 62%, and 56%. Survival was not significantly different for subsets with rejection on any combination of the first 3 biopsies (1/3, 2/3, 3/3) or absence of rejection on the first 3 biopsies. Ninety-one positive biopsy results were graded. Eighteen of 71 patients had one or more moderate or severe rejection episodes without survival difference relative to the others. There was no statistically significant association between acute rejection on the first 3 surveillance biopsy results and bronchiolitis obliterans. CONCLUSIONS: Intensive induction and maintenance immunotherapy with surveillance transbronchial biopsies and aggressive treatment of acute rejection is associated with a survival similar to that of patients without early acute rejection. This regimen appears to uncouple the association between early acute rejection and bronchiolitis obliterans. Further study may elucidate this mechanism.  相似文献   
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PURPOSE: The International Continence Society (ICS) ICSmale questionnaire was devised to provide a thorough evaluation of the occurrence and bothersomeness of lower urinary tract symptoms and their impact on the lives of men with benign prostatic disease. This report completes the developmental work on the questionnaire, producing the concise short form instrument, ICSmaleSF, with a valid, reliable and scientifically justified scoring system. MATERIALS AND METHODS: Two data sets were used. The short form version of the questionnaire was devised and initially evaluated using data on men with uncomplicated lower urinary tract symptoms who were involved in the CLasP randomized controlled trial comparing laser therapy with transurethral prostatic resection and conservative management or monitoring without active intervention. External validation of the scoring system was undertaken using data from phase II of the ICS benign prostatic hyperplasia (BPH) study, an observational study of outcome in men with lower urinary tract symptoms related to benign prostatic enlargement. All patients completed the developmental version of the ICSmale questionnaire. Parallel analysis on the CLasP data set identified items that were responsive to change or highly problematic, allowing other redundant and overlapping items to be eliminated. Factor analysis and Cronbach's alpha coefficients were used to examine the clustering of items. Regression models were used to investigate the validity of followup scores within and across treatment groups in the CLasP and ICS/BPH studies. RESULTS: The questionnaire, which originally comprised 22 items, was shortened to 11 items in the 2 distinct factors of voiding (ICSmaleVS) and incontinence (ICSmaleIS) symptoms. Cronbach's alpha coefficients were high at 0.76 for ICSmaleVS and 0.78 for ICSmaleIS. A simple additive score was calculated by adding the 5 items in ICSmaleVS and 6 in ICSmaleIS. ICSmaleVS and ICSmaleIS detected expected improvement in the laser therapy and transurethral prostatic resection groups, and stability in the conservative management group within CLasP. Similarly each subscore but particularly ICSmaleVS was sensitive to differences in the outcome of the range of treatments in the ICS/BPH study. While frequency and nocturia were highly problematic and sensitive to change individually, they did not load into the other main factors or correlate with each other. It is suggested that these symptoms should be evaluated separately with the additional inclusion of a single item measure of the impact of lower urinary tract symptoms on daily life. CONCLUSIONS: The ICSmaleSF represents a comprehensive, concise, valid and reliable instrument for evaluating men with lower urinary tract symptoms. Unlike other questionnaires in the field it contains subscores for the domains of voiding and incontinent symptoms as well as the separate consideration of frequency, nocturia and impact on daily life. We hope that it will become the tool of choice for the comprehensive evaluation of treatment of men with lower urinary tract symptoms associated with benign prostatic disease.  相似文献   
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PURPOSE: We assessed the effectiveness of laser therapy versus transurethral prostatic resection in men with symptomatic chronic urinary retention secondary to benign prostatic enlargement. MATERIALS AND METHODS: This trial was multicenter, pragmatic and randomized. Analysis was done by intent to treat. Laser therapy involved neodymium:YAG noncontact visual prostate ablation, while transurethral prostatic resection was performed by standard electroresection. Patients were included in our study if they reported moderate to severe lower urinary tract symptoms with an International Prostate Symptom Score (I-PSS) of 8 or more, benign prostatic enlargement and a persistent post-void residual urine volume of more than 300 ml. Followup was 7.5 months. Primary outcome measures included the I-PSS, I-PSS quality of life score, maximum urinary flow and post-void residual urine volume. Secondary outcome measures included treatment failure, complications, hospital stay and catheterization time. RESULTS: A total of 82 patients agreed to be randomized to receive laser therapy (38) or transurethral prostatic resection (44). There were significant improvements in all primary outcomes in each group from randomization to followup. Transurethral prostatic resection was significantly better than laser therapy for I-PSS and maximum urinary flow values (p = 0.035 and 0.029, respectively) but there were no differences in post-void residual urine volume and I-PSS quality of life score between the groups. We noted significantly more treatment failures with laser therapy than resection (8 versus 0, p = 0.0014), although only 3 patients required resection after laser therapy because of persistent symptoms. In addition, hospital stay after resection was 2-fold that after laser therapy (ratio of geometric means 2.01, 95% confidence interval 1.54 to 2.61, p <0.0001). However, time to catheter removal was 9 times longer in the laser therapy group (p <0. 0001). Complication rates were significantly higher for transurethral prostatic resection (chi-square 5.05, 1 df, p = 0.025). CONCLUSIONS: Transurethral prostatic resection is more effective than laser ablation in men with chronic urinary retention in terms of symptom score, maximum urinary flow and failure. However, men who underwent resection had significantly more treatment complications and were hospitalized longer than those who received laser therapy. This finding implies that laser ablation therapy may have a role in patients at higher risk who are willing to accept a lower level of effectiveness in exchange for decreased complication rates and hospital stay.  相似文献   
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