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11.
BACKGROUND AND PURPOSE:Cervical spine axial MRI T2-hyperintense fluid signal of the anterior median fissure and round hyperintense foci resembling either the central canal or base of the anterior median fissure are associated with a craniocaudad sagittal line, also simulating the central canal. On the basis of empiric observation, we hypothesized that hyperintense foci, the anterior median fissure, and the sagittal line are seen more frequently in patients with Chiari malformation type I, and the sagittal line may be the base of the anterior median fissure in some patients.MATERIALS AND METHODS:Saggital line incidence and the incidence/frequency of hyperintense foci and anterior median fissure in 25 patients with Chiari I malformation and 25 contemporaneous age-matched controls were recorded in this prospective exploratory study as either combined (hyperintense foci+anterior median fissure in the same patient), connected (anterior median fissure extending to and appearing to be connected with hyperintense foci), or alone as hyperintense foci or an anterior median fissure. Hyperintense foci and anterior median fissure/patient, hyperintense foci/anterior median fissure ratios, and anterior median fissure extending to and appearing to be connected with hyperintense foci were compared in all, in hyperintense foci+anterior median fissure in the same patient, and in anterior median fissure extending to and appearing to be connected with hyperintense foci in patients with Chiari I malformation and controls.RESULTS:Increased sagittal line incidence (56%), hyperintense foci (8.5/patient), and anterior median fissure (4.0/patient) frequency were identified in patients with Chiari I malformation versus controls (28%, 3.9/patient, and 2.7/patient, respectively). Increased anterior median fissure/patient, decreasing hyperintense foci/anterior median fissure ratio, and increasing anterior median fissure extending to and appearing to be connected with hyperintense foci/patient were identified in Chiari subgroups. A 21%–58% increase in observed anterior median fissure extending to and appearing connected to hyperintense foci in the entire cohort and multiple sagittal line subgroups compared with predicted occurred.CONCLUSIONS:In addition to the anticipated increased incidence/frequency of sagittal line and hyperintense foci in patients with Chiari I malformation, an increased incidence and frequency of anterior median fissure and anterior median fissure extending to and appearing to be connected with hyperintense foci/patient were identified. We believe an anterior median fissure may contribute to a saggital line appearance in some patients with Chiari I malformation. While thin saggital line channels are usually ascribed to the central canal, we believe some may be due to the base of the anterior median fissure, created by pulsatile CSF hydrodynamics.

Axial MR imaging of the cervical spine frequently demonstrates hyperintense, linear, anatomically, sagittally-oriented T2 fluid signal of the anterior median fissure (AMF) and hyperintense foci (HIF) resembling the central canal or the base of the AMF.1-3 These axial T2 findings may be associated with a channel-like T2-hyperintense craniocaudad line on images parallel to the sagittal plane (a sagittal line [SL]), simulating the central canal (Fig 1).4,5 A previous analysis of HIF, AMF, and a thin SL in a population without Chiari I malformation provided not only a baseline for their identification but also a confirmation of a relationship between not only the AMF and HIF but also their relationship to the SL.1 It found the following:
  1. HIF were greater in number than AMFs, but AMFs increase in the presence of increasing HIF, suggesting an anatomic relationship.
  2. SLs were associated with greater numbers of both HIF and AMF/patient (pt.) versus no SL, 6.7 versus 2.7/pt. and 3.3 versus 2.0/pt., respectively. SL presence correlated more closely to HIF than to AMF presence within the entire 358-patient group.
  3. When HIF and AMF were classified as combined (concurrent HIF and AMF, with ≥1 of each both present in the same patient [HIF+AMF]) or continuous (AMF appearing to extend to and join an HIF [AMF>HIF]), HIF and AMF/pt. each differed numerically and patients with an SL had more combined HIF+AMF and continuous AMF>HIF than patients without an SL.
  4. In patients with both SL and combined HIF+AMF (a circumstance allowing the possibility of a relationship of all 3 structures), HIF become proportionally fewer compared with AMFs. In patients with an SL actually exhibiting continuous AMF>HIF, the HIF/AMF ratio decreased further.
Open in a separate windowFIG 1.A patient with Chiari I with 19 HIF up to 3 mm in diameter, 1 AMF, no AMF>HIF, and an SL of various hyperintensity and diameter from C4 through T1, consistent with hydromyelia.While it is expected that manifestations of the central canal as an SL and HIF are more frequent in patients with Chiari syndrome type I,6 past experience leads us to hypothesize that AMFs are also seen more frequently in patients with Chiari I malformation and that the SL or channel may represent the base of a wide AMF, rather than the central canal, in some patients (Figs 1 and and2).2). Therefore, we performed an exploratory prospective analysis of HIF, AMF, and SL in patients with Chiari I malformation to examine their relationships.Open in a separate windowFIG 2.Postdecompressive craniectomy patient with Chiari I with 9 HIF, 4 AMFs, 1 AMF>HIF, and sharp and hyperintense SLs at C6–C7 and less hyperintense, sharp, and defined SLs at C2–C6.  相似文献   
12.
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Purpose/aim: To focus on current aspects of primary thyroid lymphoma (PTL), which is a rare clinical entity usually manifested by a rapidly growing mass in the neck that can cause pressure symptoms.

Materials and Methods: Relevant papers in PubMed published through June 2017 were selected to track updated information about PTL with an emphasis on diagnosis and novel therapeutic management.

Results: The most frequent cases include non-Hodgkin lymphoma derived from B-cells, mainly diffuse large B-cell lymphoma (DLBCL) followed by mucosa-associated lymphoid tissue (MALT) lymphoma or a mixed type. Other subtypes are less common. Lymphomas derived from T-cells and Hodgkin lymphomas are extremely rare. Hashimoto's autoimmune thyroiditis has been implicated as a risk factor for lymphoma. At the molecular level, the Wnt5a protein and its receptor Ror2 are involved in the course of the disease. Ultrasonography, fine needle aspiration (FNA) biopsy, and core or open biopsy combined with new diagnostic facilities contribute to an accurate diagnosis. An increased potential exists for a cure without the need for a radical surgical procedure. Modern chemoradiation therapy plus the monoclonal antibody rituximab, which acts against CD20, have limited the need for surgical interventions and provide an excellent outcome in most cases. However, some cases have resulted in treatment failure or recurrence.

Conclusions: A multidisciplinary approach must be used to define the management policy in each case. Future efforts by researchers are likely to be focused on the molecular level.  相似文献   

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15.
Objectives: There is a paucity of reporting on surgical outcomes of isolated posterior cruciate ligament reconstruction (PCLR). We hypothesize that isolated PCL injuries failing nonoperative treatment achieve good outcomes and are able to return to sport following PCLR.

Methods: A retrospective analysis was performed to identify patients with isolated PCL injuries that underwent reconstruction between 2001 and 2014. Patients with multi-ligamentous injury or another concomitant knee pathology were excluded. Medical records were reviewed for demographic, clinical and operative data. Patients were contacted for administration of a telephone-based questionnaire which included the International Knee Documentation Committee (IKDC) Subjective Knee Evaluation form, Lysholm-Tegner scales, Marx activity scale (MAS), return to sport status, and patient satisfaction instruments.

Results: A total of 15 isolated PCL reconstructions in 14 patients with a mean age of 27.5 years (range 17–43) met the study inclusion criteria; mean follow up was 6.3 years (range 1.4–15.2). Pre-operatively, the primary complaint was knee instability in all patients; on physical examination, lack of a firm end point during posterior drawer testing was found in 93% (14/15) of the knees. In total, 12 of 15 knees underwent transtibial, single-bundle PCLR and three of 15 underwent tibial inlay, double bundle PCLR. Graft types included: quadriceps autograft (7/15), Achilles allograft (6/15), and hamstring autograft (2/15). There were no graft failures in our patient cohort. At most recent follow up the mean scores respectively on the IKDC form, Lysholm-Tegner scales and MAS were (standard deviation): 77.3 (16.5), 83.1 (17.9), 6.13 (2.6), and 7.1 (6.0). All fourteen patients were athletes prior to their injury and 79% (11/14) returned to sport and overall patient satisfaction was 9.2/10.

Conclusions: Isolated PCLR provides good outcomes at mean medium-term follow up with restoration of function, high rate of return to sport and overall patient satisfaction.  相似文献   

16.

Background

Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain.

Methods

We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male).

Results

Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians.

Conclusions

Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation.  相似文献   
17.
This paper reviews the published literature on a group of developmental disorders of the retina and retinal pigment epithelium which result in focal abnormalities in one or both eyes. They are often asymptomatic, found on routine examination and are generally non-progressive. Some are associated with other systemic abnormalities.Subject terms: Retinal diseases, Eye abnormalities  相似文献   
18.

Introduction

The nature of community pharmacy is changing, shifting from the preparation and distribution of medicines to the provision of cognitive pharmaceutical services (CPS); however, often the provision of traditional services leaves little time for innovative services. This study investigated the time community pharmacists spend on the tasks and activities of daily practice and to what extent they are able to implement CPS-related services in daily practice.

Methods

Self-reporting work sampling was used to register the activities of community pharmacists. A smartphone application, designed specifically for this purpose, alerted participants to register their current activity five times per working day for 6 weeks. Participants also completed an online survey about baseline characteristics.

Results

Ninety-one Dutch community pharmacists provided work-sampling data (7848 registered activities). Overall, 51.5% of their time was spent on professional activities, 35.4% on semi-professional activities, and 13.1% on non-professional activities. The proportion of time devoted to CPS decreased during the workweek, whereas the time spent on traditional task increased.

Discussion and conclusion

This study shows it is feasible to collect work-sampling data using smartphone technology. Community pharmacists spent almost half of their time on semi-professional and non-professional activities, activities that could be delegated to other staff members. In practice, the transition to CPS is hampered by competing traditional tasks, which prevents community pharmacists from profiling themselves as pharmaceutical experts in daily practice.  相似文献   
19.
20.
ZusammenfassungHintergrund Bedingt durch die intraoperative Katecholaminsekretion mit hämodynamischen Veränderungen, einem größeren Tumordurchmesser und einer deutlichen Neovaskularisation ist die Adrenalektomie beim Phäochromozytom im Vergleich zu anderen Nebennierenerkrankungen schwieriger und potenziell komplikationsträchtiger. Ziel unserer Studie war die Frage, ob das Risiko intraoperativer kardiovaskulärer Komplikationen durch das minimal-invasive Vorgehen potenziert wird.Patienten und Methodik Im Zeitraum zwischen Februar 1992 und Mai 2005 wurden in unserer Klinik 82 Eingriffe wegen eines Phäochromozytoms bei 71 Patienten durchgeführt. Davon wurden 8 (1) Patient(en) bi-(tri-)lateral adrenalektomiert und bei 2 Patienten erfolgte eine ipsilaterale Rezidivoperation. Eingeschlossen sind 5 weitere Patienten mit Rezidiv nach Erstoperation vor 1992. Sechsunddreißig Eingriffe erfolgten konventionell (transperitoneal n=35, retroperitoneal n=1) und 46 Operationen endoskopisch (transperitoneal n=28, retroperitoneal n=18), davon keine Konversion zum offenen Vorgehen.Ergebnisse Das mediane Alter zum Zeitpunkt der Operation betrug 45 (24–75) Jahre bei einer Anamnesedauer von 12 (0–180) Monaten. Die offen operierten Phäochromozytome waren mit 5,5 (1–19) cm vs. 3,5 (0,5–8) cm (endoskopisch) signifikant größer (p=0,0011). Patienten mit endoskopischer, insbesondere mit retroperitoneoskopischer Adrenalektomie hatten im Vergleich zum konventionellen Vorgehen intraoperativ höhere systolische und diastolische maximale Blutdruckwerte sowie Spitzen über 200 mmHg (statistisch nicht signifikant). Faktoren mit möglichem Einfluss auf intraoperative hämodynamische Veränderungen waren in der multivariaten Analyse das Geschlecht (p=0,0107), der operative Zugangsweg (p=0,0153), das Patientenalter (p=0,0364) und die Tumorgröße (p=0,0484). Die postoperative stationäre Verweildauer war nach endoskopischer Operation signifikant kürzer (p<0,0001).Schlussfolgerung Die endoskopische Adrenalektomie beim Phäochromozytom ist in der Routine ohne vermehrtes Risiko kardiovaskulärer Komplikationen die Methode der Wahl. Das offene Vorgehen sollte extraadrenalen Befunden oder sehr großen Tumoren mit Malignitätsverdacht vorbehalten bleiben.   相似文献   
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