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141.
The effects of human recombinant plasminogen activator inhibitor (rPAI-1) on thrombolysis with recombinant tissue-type plasminogen activator (rt-PA) were studied in a rabbit model of jugular vein thrombosis. Two functionally distinct rPAI-1 preparations were used in these experiments, including latent rPAI-1 (approximately 2 units of t-PA neutralizing activity per micrograms protein) and reactivated rPAI-1 (approximately 150 units/micrograms). Simultaneous intravenous infusion over 4 h of 1.7 mg/kg of reactivated rPAI-1 (inhibitory capacity approximately 0.5 mg/kg rt-PA) with 0.5 mg/kg of rt-PA completely prevented lysis of a jugular venous thrombus, whereas an equivalent amount of latent PAI-1 did not significantly influence clot lysis. These findings demonstrate that reactivated human rPAI-1 efficiently neutralizes thrombolysis with rt-PA in vivo. Since previous studies have suggested that elevated endogenous levels of PAI-1 do not attenuate the thrombolytic potency of rt-PA in the endotoxin-treated model, we compared the stability of complexes formed by 125I-rt-PA with reactivated human rPAI-1 and with rabbit PAI-1 in vitro. Our findings indicate that both forms of PAI-1 form SDS-stable complexes following incubation with 125I-rt-PA. Thus, it seems likely that elevated levels of active PAI-1 can negate the thrombolytic effects of rt-PA in vivo and argues against the possibility that t-PA can dissociate from PAI-1 and have its activity restored in the presence of a thrombus.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
142.
S9788 is a new triazineaminopiperidine derivate capable of reversing multidrug resistance (MDR) in cells resistant to chemotherapeutic agents such as doxorubicin. It does not belong to a known class of MDR revertants, but its action involves the binding of P-glycoprotein. Thirty-eight evaluable patients with advanced colorectal or renal cell cancer were treated with doxorubicin alone (16 patients) followed after disease progression with combination treatment of doxorubicin plus S9788 (12 patients) or upfront with the combination of doxorubicin plus S9788 (22 patients). S9788 was given i.v. as a loading dose of 56 mg m-2 over 30 min followed by doxorubicin given at 50 mg m-2 as a bolus infusion. Thereafter, a 2-h infusion of S9788 was administered at escalating doses ranging from 24 to 120 mg m-2 in subsequent cohorts of 4-10 patients. Pharmacokinetic analysis demonstrated that concentrations of S9788 that are known to reverse MDR in vitro were achieved in patients at non-toxic doses. Compared with treatment with doxorubicin alone, treatment with the combination of doxorubicin and S9788 produced a significant increase in the occurrence of WHO grade 3-4 granulocytopenia. Treatment with S9788 was cardiotoxic as it caused a dose-dependent and reversible increase in corrected QT intervals as well as clinically non-significant arrhythmias on 24- or 48-h Holter recordings. Although clinically relevant cardiac toxicities did not occur, the study was terminated as higher doses of S9788 may increase the risk of severe cardiac arrhythmias. Twenty-nine patients treated with S9788 plus doxorubicin were evaluable for response, and one patient, who progressed after treatment with doxorubicin alone, achieved a partial response. We conclude that S9788 administered at the doses and schedule used in this study results in relevant plasma concentrations in humans and can safely be administered in combination with doxorubicin.  相似文献   
143.
The effects of diazepam and lorazepam on explicit memory and perceptual priming were studied 50, 130 and 300 min after drug administration. Sixty healthy volunteers were randomly assigned to one of five parallel groups (placebo, diazepam 0.2 or 0.3 mg/kg, lorazepam 0.026 or 0.038 mg/kg). The corresponding doses of benzodiazepines exerted a similar negative effect on explicit performance. Lorazepam markedly impaired priming performance, whereas the effect of diazepam was intermediate between that of placebo and that of lorazepam 0.038 mg/kg. The impairment was maximal at the theoretical peak plasma concentration. Contamination by explicit memory could account for the decrease in priming performance observed in the diazepam groups.  相似文献   
144.
The aim of this study was to determine whether urge incontinence was associated with a higher prevalence of psychological symptoms than other types of incontinence. The psychological aspects of 110 women presenting with urinary incontinence in general practice were assessed by means of standardised questionnaires and medical history-taking. The results showed no difference in psychological characteristics between patients with urge incontinence and those with other types of incontinence. These findings were contrary to the conclusions of almost all other studies based on populations selected for specialist care. It was concluded that in general practice the psychological approach to urinary incontinence depends more on the individual needs of the patient than specifically on the type of incontinence.  相似文献   
145.
Patients treated for sporadic and hereditary medullary thyroid carcinoma (MTC) have varying rates of persistent disease, recurrence, and survival. The aim of this study was to correlate the immunoreactivity of the monoclonal antibody CD15 (LeuM1) to initial clinical findings and the outcome of treatment. The primary tumors of 75 patients with sporadic MTC, 7 with hereditary disease, and 3 members of MEN 2A families were studied. Of these subjects 74 (87%) showed no or little immunoreactivity (<15% positive cells; score 0) in most tumors. The remaining 13% had surgery for tumors with more than 15% cells with positive staining (score I). There was no correlation between LeuM1 immunoreactivity and sex, age, and type of MTC. There was, however, a significant correlation with the pTNM classification and UICC staging. The prognosis for patients with score 0 was significantly better than score 1 patients. CD15 immunoreactivity appears to be a predictive factor in sporadic and hereditary MTC. Lymph node dissection seems to be more successful in patients with score 0 tumors than in those with score 1 tumors. The question of reoperation in patients with recurrence of disease (especially with biochemical recurrence or persistence) should be discussed on the basis of CD15 immunoreactivity.
Resumen Los pacientes tratados para carcinoma medular, esporádico y hereditario, de la glándula tiroides (CMT) exhiben grandes variaciones en las tasas de enfermedad persistente, recidiva y sobrevida. El propósito del presente estudio fue establecer la correlación entre la inmunorreactividad del anticuerpo CD15 (LeuM1) y los hallazgos clínicos iniciales, así como con el resultado final del tratamiento.Se estudiaron los tumores primarios de 75 pacientes con CMT esporádico, de siete con enfermedad hereditaria y de 3 miembros de familias con síndrome NEM2A.Setenta y cuatro pacientes (87%) exhibieron ninguna o muy baja inmunorreactividad (menos de 15% de células positivas; puntaje 0) en la mayoría de los tumores. El 13% restante fue sometido a cirugía por tumores con más de 15% de las células con coloración positiva (puntaje 1). No se evidenció correlación entre la inmunorreactividad LeuM1 y el sexo, edad o tipo del CMT. Sin embargo, sí apareció una correlación significativa con la clasificiación pTNM y la estadificación de la UICC. El pronóstico de los pacientes con puntaje 0 resultó significativamento mejor que el de los pacientes con puntaje 1.La inmunorreactividad CD15 parece ser un factor de predicción de pronóstico en el CMT esporádico y familiar. La disección ganglionar parece ser más exitosa en pacientes con tumores de puntaje 0 que en los que portan tumores con puntaje 1.El interrogante en cuanto a reoperación en pacientes con recidiva de la enfermedad (especialmente cuando hay recidiva o persistencia bioquímica) debe ser considerada con base en la inmunorreactividad CD15.

Résumé Les taux de maladie persistante, de récidive et de survie chez des patients traités pour cancer médullaire sporadique et héréditaire de la thyroïde (CMT) sont très variables. Le but de cette étude a été de corréler l'immunoréactivité des anticorps monoclonaux CD15 (LeuM1) à des données cliniques initiales et l'évolution finale du traitement des CMT. On a étudié 75 patients ayant un CMT primitif, sept ayant une maladie héréditaire, et trois membres d'une famille MEN 2A. Soixante quatre patients (87%) avaient peu ou pas d'immunoréactivité (moins de 15% de cellules positive: score = 0). Les 13% restants ont eu une chirurgie pour les tumeurs ayant un pourcentage > 15 (score = 1). Il n'y avait aucune corrélation entre l'immunoréactivité LeuM1 et le sexe, l'âge et le type de CMT. Il y avait, en revanche, une corrélation significative entre la classification pTMN et le stage UICC. Le pronostic des patients ayant un score = 0 était significativement meilleur que celui des patients ayant un score = 1. L'immunoréactivité CD15 apparaît comme étant un facteur pronostique des CMT. Le curage lymphatique


Members and institutions are listed in Table 1.  相似文献   
146.
Introduction: Opioid-induced rigidity often makes bag-mask ventilation difficult or impossible during induction of anesthesia. Difficult ventilation may result from chest wall rigidity, upper airway closure, or both. This study further defines the contribution of vocal cord closure to this phenomenon.

Methods: With institutional review board approval, 30 patients undergoing elective cardiac surgery participated in the study. Morphine (0.1 mg/kg) and scopolamine (6 micro gram/kg) given intramuscularly provided sedation along with intravenous midazolam as needed. Lidocaine 10% spray provided topical anesthesia of the oropharynx. A fiberoptic bronchoscope positioned in the airway photographed the glottis before induction of anesthesia. A second photograph was obtained after induction with 3 micro gram/kg sufentanil administered during a period of 2 min. A mechanical ventilator provided 10 ml/kg breaths at 10/min via mask and oral airway with jaw thrust. A side-stream spirometer captured objective pulmonary compliance data. Subjective airway compliance was scored. Pancuronium (0.1 mg/kg) provided muscle relaxation. One minute after the muscle relaxant was given, a third photograph was taken and compliance measurements and scores were repeated. Photographs were scored in a random, blinded manner by one investigator. Wilcoxon signed rank tests compared groups, with Bonferroni correction. Differences were considered significant at P <0.05.

Results: Twenty-eight of 30 patients exhibited decreased pulmonary compliance and closed vocal cords after opioid induction. Two patients with neither objective nor subjective changes in pulmonary compliance had open vocal cords after opioid administration. Both subjective and objective compliances increased from severely compromised values after narcotic-induced anesthesia to normal values (P = 0.000002) after patients received a relaxant. Photo scores document open cords before induction, progressing to closed cords after the opioid (P = 0.00002), and opening again after a relaxant was administered (P = 0.00005).  相似文献   

147.
In this text we briefly want to discuss the role of the arthrographic examination of the temporomandibular joint for detection of disc pathology. We will mention the normal anatomy and function of the temporomandibular joint, the technique for performing arthrograms and the classification of the most frequent disc pathology. This will be illustrated by some arthrographic examples of anterior disc displacement without reduction, disc perforation, and medial disc displacement. Finally the advantages of arthrography in comparison with other investigation techniques will be discussed.  相似文献   
148.
As an octanoic acid 13CO2 breath test is frequently used to test gastric emptying of solid food, the purpose of the present study was to study whether oxidative breakdown of octanoic acid is affected by severe liver disease. The design of our study was twofold. First, cirrhotic patients (n = 82) of varying severity were compared with healthy controls (n = 17). Values of half-time, time point of maximal expiration and cumulative recovery of octanoic acid breath tests (OBT) were not significantly different between them. Secondly, cirrhotic patients (n = 10) were studied before placement of transjugular intrahepatic portosystemic shunt, 4-7 days later and 1-2 months later. Values of half-time, time point of maximal expiration and cumulative recovery of consecutive OBTs did not change significantly. The OBT may therefore be a suitable test in the future to detect delayed gastric emptying of solids in cirrhotic patients with reduced liver function and portal hypertension.  相似文献   
149.
A number of continuous epitopes of tobacco mosaic virus protein (TMVP) have been defined by the pepscan technique using polyclonal and monoclonal antibodies to TMVP as well as antisera raised against synthetic peptides. In general, the location of continuous epitopes agreed with the results of earlier studies with peptides synthesized by classical methods although there were some notable exceptions. Results obtained with the different types of antibodies used in this study indicated that a homology of three residues was sufficient to give rise to antigenic cross-reactions. In the case of antibodies raised against a peptide conjugated to ovalbumin, some unexpected cross-reactivities could be explained by assuming that antibodies to the carrier molecule recognized homologous tripeptide sequences in TMVP and ovalbumin.  相似文献   
150.
OBJECTIVES: To present a series of women with recurrent molar pregnancies, including rare familial cases, and discuss etiology and treatment options. METHODS: We performed a detailed clinical evaluation and pedigree analysis of five Egyptian women with recurrent pregnancy loss due to molar pregnancy. RESULTS: The women had a history of four to nine consecutive hydatidiform moles but of no viable pregnancies. Two of the women had molar pregnancies with different husbands who themselves had viable offspring from previous wives; and three of them, who belonged to a family with extensive intermarriage, had a pedigree consistent with an autosomal recessive maternal-effect mutation. CONCLUSIONS: Recurrent pregnancy loss due to habitual molar pregnancy is uncommon and familial cases are extremely rare. The etiology of this disorder is not well understood but likely results from a maternal-effect mutation. Management options are limited, especially for couples who desire to have their own genetic offspring.  相似文献   
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