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41.
A 14-year-old boy had a 1-month history of diplopia (due to a VI nerve palsy), motor ataxia and dizziness. Brain MRI showed
a 1.5-cm mass posterior to the pons. Histopathological examination of a biopsy specimen showed the lesion to be of viral origin.
After 3 months, the ataxia and dizziness had resolved and the MRI findings returned to normal. By 5 months the abducens paralysis
had also resolved. Viral encephalitis should be considered in the differential diagnosis of posterior fossa tumours.
Received: 20 March 1997 Accepted: 16 April 1997 相似文献
42.
A comparison of spiral and conventional computerized tomography methods in diagnosing various laryngeal lesions 总被引:1,自引:0,他引:1
H. Korkmaz N. G. Çerezci H. Akmansu E. Dursun 《European archives of oto-rhino-laryngology》1998,255(3):149-154
Although endoscopic procedures with tissue biopsy are the mainstay in the evaluation of laryngeal lesions, radiological imaging
studies remain important. Computerized tomography (CT), magnetic resonance imaging (MRI) and ultrasound (US) are the most
reliable methods, especially for deep laryngeal compartments, cartilage, extralaryngeal structures and neck nodes. However,
the larynx is a difficult organ for radiological imaging because respiration and swallowing can cause several artifacts and
distort image. In this report we studied the role of a spiral CT technique and compared this with conventional CT in 32 patients.
We used the Hitachi W950SRBT machine and took both conventional and spiral sections of the larynx and neck in all 32 patients.
The scans were taken with a 5-mm table motion and 5-mm section thickness in both studies. In the spiral technique the raw
data acquired were used retrospectively for 2-mm and 5-mm reconstructions. Anatomic details, motion artifacts and vascular
enhancements were compared by a scoring system. The mean values were then analyzed statistically by the paired t-test. The average examination time was 3 min 18 s for conventional CT and 28 s for spiral CT. Anatomic detail scores were
better in the 2-mm section spiral CT studies compared to 5-mm section spiral and conventional CT groups. Motion artifact scores
were better in the 2-mm and 5-mm spiral CT groups compared to the 5-mm conventional CT group. Vascular enhancement scores
were better in the spiral CT group. Overall, the thinner (2-mm) sections of the spiral CT studies further improved image quality
regarding both anatomic details and motion artifacts. Scanning time for spiral CT was very short, motion artifacts were less,
and vascular enhancement and anatomic details were better. Volumetric data could also be reconstructed for thinner sections
in all planes retrospectively for further evaluation. Our findings showed that spiral CT was a better method than conventional
CT for evaluating laryngeal lesions.
Received: 4 December 1996 / Accepted: 18 August 1997 相似文献
43.
M. Benekli I. H. Güllü G. Tekuzman M. C. Sava? M. Hayran G. Has?elik D. Firat 《British journal of cancer》1998,78(2):267-271
A diversity of adhesive interactions occur between the cancer cell and host extracellular matrix which potentiate neoplastic expansion and metastatic dissemination. In miscellaneous malignant diseases, tumour progression has been observed to be associated with alterations in adhesion molecule expression. Recently, circulating soluble intercellular adhesion molecules have been identified. In this study, serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) and soluble E-selectin (sE-selectin) were determined in patients with gastric cancer. The study group consisted of 27 patients with previously untreated gastric adenocarcinoma. Four patients had stage II, two patients stage III and 21 patients stage IV disease according to the TNM classification. Nineteen patients had distant metastasis. The sera obtained from 18 healthy volunteers served as controls. Serum sICAM-1 and sE-selectin concentrations were determined by enzyme-linked immunosorbent assay (ELISA). In addition, we also studied other tumour-associated antigens, i.e. CEA and CA 19-9. Serum sICAM-1 levels were significantly increased in patients with gastric cancer (P < 0.0001). However, sE-selectin levels did not differ from the controls. sICAM-1 concentrations were also significantly higher in patients with distant metastasis and peritoneal spread (P = 0.0045 and P = 0.0157 respectively), whereas sE-Selectin levels were elevated only in patients with peritoneal metastasis (P = 0.033). Serum concentrations of sICAM-1 and sE-selectin correlated with CEA levels (P = 0.0013 and P = 0.003 respectively). Elevated levels of sE-selectin were associated with poorer prognosis (P = 0.0099), whereas sICAM-1 had no significant impact on survival. Our results suggest that increased sICAM-1 serum levels may reflect widespread disease and contribute directly to the progression of gastric cancer. Further investigation of the molecular mechanisms of adhesive tumour-host interactions may lead to a better understanding of the natural history of gastric cancer. 相似文献
44.
Berkman MZ Iplikçioğlu AC Berkman MK Erbengi T San T Sav A 《Acta neurochirurgica》2000,142(9):1047-1054
Summary ? Background. Cerebral vasospasm after subarachnoid hemorrhage (SAH) has remained a major cause of morbidity and mortality in patients
with SAH. Excitatory neurotransmitters are gathered in the extracellular space during ischemia due to cerebral vasospasm and
initiate or stimulate a series of pathophysiological biochemical processes which consequently lead to neuronal death. Tizanidine
(Sandoz compound DS 103–282, 5-chloro-4,2 (2-imidazolin-2-yl-amino)-2,1,3-benzothiazol hydrochloride) is a centrally-acting
muscle relaxant and a selective α 2 adrenoreceptor agonist which shows its effect by stimulating presynaptic α 2 adrenoreceptors
in central ASPergic and GLUergic system by inhibiting aspartic acid and glutamic acid release. In this study, the effect of
Tizanidine on vasospasm was evaluated.
Methods. We used a femoral artery vasospasm model in rats which has been described by Okada et al. 60 rats were examined in three groups. The first group was used as control group (Control) (n=20), in the second group subarachnoid
hemorrhage was performed (SAH) (n=20), in the third group Tizanidine was administered in addition to SAH (SAH+Tizanidine administration)
(n=20). Animals in SAH+Tizanidine administration group received 0,3 mg/kg/day intraperitoneally for 7 days. Seven days after
the experiment, after perfusion-fixation, 10 mm segments of both femoral arteries were removed and the femoral artery was
prepared for light microscope examination, scanning and transmission electron microscopy and for morphometric analysis.
Results. There was a statistically significant difference between the electron, scanning and light microscopic observations and morphometric
analysis of SAH+Tizanidine administration group and SAH group, and no statistically significant difference between SAH+Tizanidine
administration group and control group.
Conclusion. This study has disclosed that Tizanidine administration before the vasospasm reduces ultrastructural and morphometric vasospastic
insult significantly. However, the clinical application of Tizanidine as a protective and therapeutic agent in cerebral vasospasm
needs further studies including the employment of clinically more relevant SAH models. 相似文献
45.
Summary The aim of this study is to find out the effects of different doses of midazolam, when used epidurally, on somatosensory
evoked potentials (SEP) by delaying neuronal conduction. Thirty two New Zeland albino male rabbits were divided into four
groups. All rabbits were anesthetised with ketamine and xylasine combination and atracurium was used as muscle relaxant. 10
mg/kg/hr ketamine infusion was used for maintenance of anesthesia. After insertion of the epidural catheter surgically; Group
1 received 1.5 ml isotonic saline (Control), Group 2 received 150 μg/kg, Group 3 received 250 μg/kg, and Group 4 received
500 μg/kg midazolam epidurally. With the stimulation of sciatic nerve, SEP records were recorded from the epidural space.
Records were received before the injection of the drug, and 20, 40, 60 minutes after injection of the drug.
“Latancy” results were increased according to control in all groups (including isotonic saline-control-group). Increase in
latancy in the control group was interpreted as due to the effect of temperature mismatch of the saline and the rabbits. While
in the first and second group amplitudes showed no differences, group 3 and 4 showed decreases of up to 50%. Epidurally administered
midazolam up to 150 μg/kg caused no change in SEP records, but 250 and 500 μg/kg doses caused decreases in SEP records which
can lead to misinterpretation as neurological damage. 相似文献
46.
Ç. Çelik K. GezginÇ M. Aktan† A. Acar S. T. Yaman S. Güngör‡ & C. Akyürek 《International journal of gynecological cancer》2004,14(4):600-606
OBJECTIVE: The aim of this study was to investigate whether the ovulation induction has relation with postneoplastic lesions. MATERIALS AND METHODS: Seventy-eight female, 90-day-old rats were enrolled for the trial. They were divided into three groups. In the first group, 13 rats received one cycle of ovulation induction with Follitropin Beta and human chorionic gonadotropin. The second group of 13 rats received three cycles of ovulation induction, and the third study group consisted of 13 rats which received six cycles of ovulation induction. Each group had a control group consisting of same number of rats that had not received ovulation induction. At the 12th month after the ovulation induction protocols ended, rat ovaries were extirpated for histopathological examination. In histopathological examination, malignant lesions, ovarian cyst and cyst diameter, epithelial stratification, epithelial tufting, mitotic index, polymorphism of epithelial cells and nucleus, epithelial cell nuclear diameter, chromatin density nuclear atypia, and mitotic activity in ovarian cyst epithelium were evaluated. RESULTS: No malignant ovarian lesion was found in the three groups. Ovarian cyst development was most frequent in the rats that underwent six cycles of ovulation induction. Epithelial stratification and tufting were most frequent in the rats which underwent ovulation induction six times. Significant difference was found between induction and control groups in second and third groups for cellular and nuclear polymorphism, presence of nucleolus, and nuclear chromatin density. CONCLUSIONS: Although development of malignant lesion were not found in any of the rat ovaries after ovulation induction, increase in the prevalence of epithelial dysplasia especially with increase in the number of induction cycles shows that some ovarian pathologies can occur subsequent to ovulation induction. 相似文献
47.
Gözde Bumin Aydın Reyhan Polat Julide Ergil Murat Sayın Ceyda Özhan Çaparlar 《Journal of anesthesia》2014,28(3):471-474
Rocuronium is a non-depolarizing neuromuscular blocking agent which is associated with injection pain and induces withdrawal movement of the injected hand or arm or generalized movements of the body after intravenous injection. The aim of this randomized study was to compare the efficacy of pretreatment with oral dexketoprofen trometamol (Arvelles®; Group A) with placebo (Group P) without tourniquet to prevent the withdrawal response caused by rocuronium injection. The study cohort comprised 150 American Society of Anaesthesiologists class I–III patients aged 18–75 years who were scheduled to undergo elective surgery with general anesthesia. The patients response to rocuronium was graded using a 4-point scale [0 = no response; 1 = movement/withdrawal at the wrist only, 2 = movement/withdrawal involving the arm only (elbow/shoulder); 3 = generalized response]. The overall incidence of withdrawal movement after rocuronium injection was significantly lower in Group A (30.1 %) than in Group P (64.6 %) (p < 0.001). The incidence of score 0 withdrawal movements was higher in Group A (69.9 %) than in Group P (35.4 %), that of score 1 withdrawal movements was similar between groups (Group A 21.9 %; Group B 26.1 %) (p = 0.560) and that of score 2 withdrawal movements was lower in Group A (8.2 %) than in Group P (38.5 %) (p < 0.001). There were no score 3 withdrawal movements in either group (p > 0.05). These results demonstrate that the preemptive administration of dexketoprofen trometamol can attenuate the degree of withdrawal movements caused by the pain of the rocuronium injection. 相似文献
48.
49.
Kamel Sadat M.D. Hari Prakash Diddi M.B.B.S. Berthold Klas B.S. Ayman Haj Asaad M.D. Elif İjlal Çekirdekçi M.D. Aylin Sungur M.D. Selvin Sudhakar M.D. Matthew Cain M.D. Arshad Kamal M.D. Navin C. Nanda M.D. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(10):1227-1231
Hypertrophic cardiomyopathy (HCM) is the most common genetically transmitted cardiomyopathy. In patients resistant to medical management, myectomy is the surgical procedure of choice to reduce the symptoms of left ventricular outflow obstruction. Two‐dimensional transesophageal echocardiography (2DTEE) has become part of the operative procedure by decreasing the incidence of postoperative complications. However, because of the three‐dimensional geometry of left ventricular outflow tract, it is unable to comprehensively assess the location and severity of the obstruction and to provide accurate guidance during myectomy. In this study, 10 patients with HCM underwent live/real time three‐dimensional transesophageal echocardiography (3DTEE) intra‐operatively to measure the volume of the resected septum. This volume correlated well with the volume of the resected septal muscle directly obtained using a graduating cylinder containing water (r = 0.9, P < 0.000). 3DTEE may be potentially used as an adjunct to guide the surgeon in performing an adequate myectomy with a lower incidence of residual obstruction and complications such as an iatrogenic ventricular septal defect. 相似文献
50.
Kudret Çağlar Selma Ünal Ahmet Çetinkaya Fatma Gümrük Sevgi Yetgin 《Pediatric hematology and oncology》2013,30(7):535-537
Second malignant neoplasm in childhood is increasing due to advances in therapy modalities. Acute lymphoblastic leukemia as a second malignancy following the treatment of medulloblastoma is a very rare condition. A 13-year-old boy was diagnosed as acute lymphoblastic leukemia following radiotherapy and chemotherapy for treatment of medulloblastoma. 相似文献