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991.
992.
993.
R Tanaka M Takamori Y Uchiyama R M Nishikawa J Shiraishi 《The British journal of radiology》2015,88(1047)
Objective:
The aim of this study was to investigate a practical method for incorporating radiographers'' reports with radiologists'' readings of digital mammograms.Methods:
This simulation study was conducted using data from a free-response receiver operating characteristic observer study obtained with 75 cases (25 malignant, 25 benign and 25 normal cases) of digital mammograms. Each of the rating scores obtained by six breast radiographers was utilized as a second opinion for four radiologists'' readings with the radiographers'' reports. A logical “OR” operation with various criteria settings was simulated for deciding an appropriate method to select a radiographer''s report in all combinations of radiologists and radiographers. The average figure of merit (FOM) of the radiologists'' performances was statistically analysed using a jackknife procedure (JAFROC) to verify the clinical utility of using radiographers'' reports.Results:
Potential improvement of the average FOM of the radiologists'' performances for identifying malignant microcalcifications could be expected when using radiographers'' reports as a second opinion. When the threshold value of 2.6 in Breast Imaging-Reporting and Data System (BI-RADS®) assessment was applied to adopt/reject a radiographer''s report, FOMs of radiologists'' performances were further improved.Conclusion:
When using breast radiographers'' reports as a second opinion, radiologists'' performances potentially improved when reading digital mammograms. It could be anticipated that radiologists'' performances were improved further by setting a threshold value on the BI-RADS assessment provided by the radiographers.Advances in knowledge:
For the effective use of a radiographer''s report as a second opinion, radiographers'' rating scores and its criteria setting for adoption/rejection would be necessary.The number of mammography examinations has been increasing. In general, double reading by two radiologists is recommended in many countries, resulting in a shortage of radiologists. In order to solve this problem, the use of computer-aided detection (CADe) systems and/or reporting by radiographers as a second opinion for radiologists'' readings have been investigated. Since many research groups have demonstrated the clinical usefulness of various CADe systems,1–6 CADe is accepted as the standard of care in the USA and is used in approximately 75% of screening examinations.6,7 On the other hand, reporting by radiographers has been recommended as another approach to aid radiologists'' readings in several countries.8–10 Although the use of CADe requires initial costs for introducing CADe systems, reporting by radiographers can be applied in almost all medical institutions without any additional facility costs. However, the practical utilization of radiographers'' reports has not been established because radiographers'' reading skills vary and owing to the insufficient evaluation of diagnostic accuracy provided by utilizing radiographers'' reports.The basic concept of “reporting by radiographers” was first developed by The College of Radiographers in 1997.8 Since the first practical guidance on reporting by radiographers was published, there have been a number of publications related to reporting by radiographers in the past decade, mainly in the UK.10–14 To utilize radiographers'' reports more practically, a new reading protocol, double reading by two radiographers, was suggested. This reading protocol is a double reading using “non-discordant radiographer only (double) readings”, in which concordant cases are automatically recalled for assessment and discordant cases (where two readers disagree over an interpretation) are arbitrated by an experienced radiologist or breast clinician.15 Several studies confirmed the benefits of reporting by radiographers in screening mammograms, including cost effectiveness benefits.16–20 Although a radiographer''s report is expected to be a substitute for one of the radiologists in a double-reading situation, questions remain, such as how to utilize a radiographer''s report in the most effective manner, as well as how to provide the best services to the patient without loss of quality.For reporting by radiographers to be effective, i.e., the highest cancer detection rate and the lowest recall rate, it is necessary to investigate the acceptance criteria to adopt or reject a radiographer''s report, as well as the acceptable performance level of a radiographer''s report. The aim of this study was to investigate a practical method on how a radiologist would adopt or reject a report provided by a single radiographer and to demonstrate the potential usefulness of radiologists reading digital mammograms utilizing radiographers'' reports. We used an existing free-response receiver operating characteristic (FROC) observer study21,22 data set to simulate all possible combinations for evaluating radiologists'' performances with and without radiographers'' reports. 相似文献994.
Varicose bleeding after liver transplantation in a patient with severe portosystemic shunts 总被引:1,自引:0,他引:1
Nosaka T Teramoto K Tanaka Y Igari T Takamatsu S Kawamura T Inoue Y Goseki N Arii S Iwai T Inomata Y Tanaka K 《Journal of gastroenterology》2003,38(7):700-703
Recipients for liver transplantation often have portosystemic shunts due to portal hypertension. It is an important problem whether such shunts should be ligated during operations. Ligating the shunts seems of benefit for increasing portal blood flow to the liver, but it is sometimes difficult technically, and it is invasive to the patient. We experienced a recipient with huge portosystemic shunts and no esophageal varices before living-related liver transplantation. Some shunts were ligated during operation to increase portal blood flow to the graft. Unfortunately, the patient suffered severe bleeding from esophagogastric varices after he underwent retransplantation owing to accidental liver failure. Based on our experience, extreme care should be exercised to avoid varicose bleeding after ligating the portosystemic shunts of liver transplantation patients. 相似文献
995.
In situ Ca2+ dynamics of Purkinje fibers and its interconnection with subjacent ventricular myocytes
Hamamoto T Tanaka H Mani H Tanabe T Fujiwara K Nakagami T Horie M Oyamada M Takamatsu T 《Journal of molecular and cellular cardiology》2005,38(4):561-569
Purkinje fibers play essential roles in impulse propagation to the ventricles, and their functional impairment can become arrhythmogenic. However, little is known about precise spatiotemporal pattern(s) of interconnection between Purkinje-fiber network and the underlying ventricular myocardium within the heart. To address this issue, we simultaneously visualized intracellular Ca(2+) dynamics at Purkinje fibers and subjacent ventricular myocytes in Langendorff-perfused rat hearts using multi-pinhole type, rapid-scanning confocal microscopy. Under recording of electrocardiogram at room temperature spatiotemporal changes in fluo3-fluorescence intensity were visualized on the subendocardial region of the right-ventricular septum. Staining of the heart with either fluo3, acetylthiocholine iodide (ATCHI), or di-4-ANEPPS revealed characteristic structures of Purkinje fibers. During sinus rhythm (about 60 bpm) or atrial pacing (up to 3 Hz) each Purkinje-fiber exhibited spatiotemporally synchronous Ca(2+) transients nearly simultaneously to ventricular excitation. Ca(2+) transients in individual fibers were still synchronized within the Purkinje-fiber network not only under high-K(+) (8 mM) perfusion-induced Purkinje-to-ventricular (P-V) conduction delay, but also under unidirectional, orthodromic P-V block produced by 10-mM K(+) perfusion. While spontaneous, asynchronous intracellular Ca(2+) waves were identified in injured fibers of Purkinje network locally, surrounding fibers still exhibited Ca(2+) transients synchronously to ventricular excitation. In summary, these results are the first demonstration of intracellular Ca(2+) dynamics in the Purkinje-fiber network in situ. The synchronous Ca(2+) transients, preserved even under P-V conduction disturbances or under emergence of Ca(2+) waves, imply a syncytial role of Purkinje fibers as a specialized conduction system, whereas unidirectional block at P-V junctions indicates a substrate for reentrant arrhythmias. 相似文献
996.
Risk factors for recurrence of large HCC in patients treated by combined TAE and PEI 总被引:11,自引:0,他引:11
Arata S Tanaka K Okazaki H Kondo M Morimoto M Saito S Numata K Nakamura S Sekihara H 《Hepato-gastroenterology》2001,48(38):480-485
BACKGROUND/AIMS: In this report, risk factors of intrahepatic recurrence of a large solitary hepatocellular carcinoma after combination therapy with transcatheter arterial embolization followed by percutaneous ethanol injection were studied. METHODOLOGY: The series included 61 patients with an unresectable large solitary hepatocellular carcinoma, the largest size of which was greater than 3 cm in diameter. All patients completely responded to combination therapy and recurrence rates were determined. The following parameters; age, sex, hepatitis B virus surface antigen, hepatitis C virus antibodies, Child's classification, alcohol abuse, alanine aminotransferase, aspartate aminotransferase, alpha-fetoprotein, indocyanine green retention rate, hepatocellular carcinoma size, hepatocellular carcinoma capsule, total amount of injected ethanol and the alpha-fetoprotein 1 month after treatment were evaluated. RESULTS: The 1-, 3-, and 5-year cancer-free survival rates of all patients were calculated to be 61%, 23%, and 13%, respectively. Among pretreatment parameters, the log-rank test and subsequent Cox's proportional hazards model showed that a tumor size of more than 5 cm in diameter was independently associated with recurrence. The posttreatment parameters of total amount of injected ethanol was also shown to be significantly related to recurrence by the log-rank test. CONCLUSIONS: Lesions more than 5 cm in diameter and insufficient injected ethanol were associated with intrahepatic recurrence after this combination therapy. 相似文献
997.
M Chang H Kim R Shigematsu H Nho T Nishijima K Tanaka 《International journal of aging & human development》2001,53(1):35-49
The relationship between functional fitness status and life satisfaction was assessed in older Japanese people from the perspective of quality of life (QOL). A total of 123 older men and women (M = 74.3 years, SD = 5.4) participated in the study. The questionnaire contained 21 questions covering eight structural factors pertaining to the feelings of life satisfaction in older people. The functional fitness test consisted of nine items representing the following five areas of fitness: muscular strength, agility, coordination, balance, and flexibility. The analysis revealed no overall correlation between the total fitness and the total life satisfaction scores, but some of the life satisfaction factors were significantly related to some functional fitness items (P < .01). The results suggest it is important for older people to maintain their functional fitness in order to manage a high quality of life. 相似文献
998.
Aldosterone nongenomically produces NADPH oxidase-dependent reactive oxygen species and induces myocyte apoptosis. 总被引:1,自引:0,他引:1
999.
We compared the growth of 183 children with short stature (≤ 2SD) and 73 children of
normal height at age six who were visiting the Tanaka Growth Clinic. We classified these
short children as suffering from either idiopathic short stature (ISS, n = 119), GH
deficiency (GHD, n = 33) or small-for-gestational-age short stature (SGASS, n = 31) on the
basis of subsequent test results and other factors. We also conducted a retrospective
study of changes in their height, wt and nutritional intake over time. The mean changes in
height SD score from birth to 6 yr were –0.24 SD in normal height children with a normal
birth length and +2.27 SD in normal height children with a low birth length. In short
children, these changes were –1.93 SD for children with ISS, –2.41 SD for those with GHD
and +0.58 for those with SGASS. The mean changes from birth to 6 mo were –0.84 SD, −1.03
SD and +0.38 SD in children with ISS, GHD and SGASS, respectively. The mean change in
height SD score from birth to age 1 yr was –1.07 SD, –1.44 SD and +0.35 SD, respectively.
The decrease in height SD score from birth to 6 mo accounted for 43.5% of the decrease in
height SD score from birth to 6 yr in children with ISS and it accounted for 42.6% of the
decrease in children with GHD. Only 19% of short children bottle-fed well, and 53% fed
poorly, as opposed to 56% and 16% of normal height children who fed well and poorly,
respectively. Post weaning, only 22% of short children ate well, and 56% fed poorly, as
opposed to 53% and 17% of normal height children who fed well and poorly, respectively.
These findings demonstrated that growth failure started from early infancy in ISS and GHD
children. It was suggested that poor nutritional intake in infancy and early childhood was
a partial cause of short stature at age 6. 相似文献
1000.
Go Miyano Keiichi Morita Masakatsu Kaneshiro Hiromu Miyake Mariko Koyama Hiroshi Nouso Masaya Yamoto Reiji Nakano Yasuhiko Tanaka Tomizo Nishiguchi Takakazu Kawamura Koji Fukumoto Naoto Urushihara 《African Journal of Paediatric Surgery》2015,12(1):86-88
We describe herein a case of unilateral pulmonary agenesis (PA) with oesophageal atresia (EA)/tracheoesophageal fistula (TEF) that was diagnosed prenatally and repaired by esophagoesophagostomy with stable postoperative course. The patient was born at 34 weeks gestation, after ultrasonography at 22 weeks gestation showed possible right-sided diaphragmatic eventration or PA and EA was subsequently suspected due to hydramnios. The initial X-ray showed mediastinal shift to the right, and coil up sign of the nasogastric tube, without intracardiac anomaly. Immediately after the diagnosis of EA/TEF and unilateral PA on day 0, the patient was intubated in the operating room, and a gastrostomy tube was placed. After pulmonary status stabilized, at 4 days old, EA/TEF was repaired through a thoracotomy in the right 4th intercostal space. The right main bronchus was noted to continue into the distal oesophagus; this fistula was ligated and divided, and a single-layer esophagoesophagostomy was performed under mild tension with one vertebral gap. The neonate was maintained on mechanical ventilation and gradually weaned to extubation at 7 days old. The postoperative course was uneventful, with the exception of prolonged jaundice that emerged at 3 months old. Laparoscopic cholangiography at that time excluded biliary atresia, and jaundice resolved spontaneously. The patient has not shown any respiratory symptoms or feeding difficulties as of the 12-month follow-up. 相似文献