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141.
Atsushi Inoue Etsuo Chosa Keisuke Goto Naoya Tajima 《Knee surgery, sports traumatology, arthroscopy》2013,21(5):1151-1157
Purpose
No studies have used stress analysis with finite element analysis (FEA) to determine the causes of and mechanisms underlying rotator cuff tears. Therefore, we performed a biomechanical evaluation of the changes in stress distribution on the rotator cuff using three-dimensional (3-D) FEA.Methods
The 3-D FEA model of shoulder joint allowed for abduction angles of 0°, 45° and 90° from the plane of the scapula and included the anatomical insertion points of the three major rotator cuff tendons and the middle fibres of the deltoid muscle. Stress distribution of the supraspinatus tendon on 3-D FEA was validated by a comparison with cadaveric and two-dimensional finite element model.Results
The principal stress peaked in the region approximately 1 cm proximal to the insertion of the supraspinatus tendon. Furthermore, the stress on the joint side increased at the anterior edge of the supraspinatus tendon at abduction angles of 45° and 90°.Conclusion
There are differences in stress changes between the joint side and bursal side of the supraspinatus tendon within the angles of abduction. The maximal tensile stress was observed on the articular side of the anterior edge of the supraspinatus tendon at 90° abduction. Our results indicate that the difference in tensile stress between the two layers results in delamination and causes partial-thickness tears.Level of evidence
Decision analysis, Level II. 相似文献142.
Yuko Suenaga Kazuhiro Kitajima Hajime Aoki Takashi Okunaga Atsushi Kono Ippei Matsumoto Takumi Fukumoto Kenichi Tanaka Kazuro Sugimura 《European journal of radiology》2013
Purpose
To ascertain the role of respiratory-gated PET/CT with 18F-fluorodeoxyglucose (18F-FDG) for accurate diagnosis of liver metastasis.Materials and methods
Forty patients with suspected liver metastasis underwent conventional whole-body PET/CT scan initially, followed by respiratory-gated PET/CT scan covering the liver. Visual detectability (using a 5-point confidence scale), maximum standardized uptake value (SUVmax) and metabolic tumor volume (MTV) of hepatic metastatic lesions were assessed for three data sets including ordinary whole-body (WB) scan, and non-respiratory-gated (nRG) and respiratory-gated (RG) scans. Results of enhanced CT and/or MRI, or clinical and radiological follow-up were used for reference.Results
Sixteen of the patients were found to have 53 metastatic lesions in the liver. Patient-based accuracy of WB, nRG, and RG was 92.5%, 95.0%, and 97.5%, respectively, with a lesion-based detection rate of 67.9%, 73.6%, and 73.6%, respectively. The average SUVmax of 34 liver metastatic lesions for WB, nRG, and RG was 6.60 ± 2.34, 7.19 ± 2.66, and 8.08 ± 3.24, respectively. SUVmax for RG was significantly higher than that for WB (p = 0.0069). The average MTV of these 40 lesions for the three protocols was 5.32 ± 4.78 cm3, 5.07 ± 4.73 cm3, and 4.73 ± 4.67 cm3, respectively. Among the three protocols, RG showed the best visual and quantitative evaluation for diagnosis of liver metastasis.Conclusion
Respiratory-gated PET/CT allows more accurate identification of liver metastases than non-respiratory-gated PET/CT. 相似文献143.
Hepatocyte transplantation and artificial organ hepatic support require a number of functionally mature hepatocytes. However, their growth activity and functional behaviors are much smaller in culture after isolation from the liver. We examined whether continuously differentiating hepatocytes from multipotent hepatic stem cells that were isolated by using flow cytometry and propagated clonally in culture could be a source of clinical application. They actually gave rise to cells that were functionally equal to mature hepatocytes found in the adult liver, which secreted albumin into culture medium and metabolized harmful ammonium into urea. These data suggest that stem cell-derived hepatocytes are a useful cell source for developing therapeutic strategies, such as cell transplantation, gene therapy, and artificial liver organ to treat various liver disorders. 相似文献
144.
Comparison of grey matter and metabolic reductions in frontotemporal dementia using FDG-PET and voxel-based morphometric MR studies 总被引:1,自引:0,他引:1
Kanda T Ishii K Uemura T Miyamoto N Yoshikawa T Kono AK Mori E 《European journal of nuclear medicine and molecular imaging》2008,35(12):2227-2234
Purpose The aim of this study was to investigate the regional differences between the morphologic and functional changes in the same
patients with frontotemporal dementia (FTD) using statistical parametric mapping and voxel-based morphometry (VBM).
Methods Thirteen FTD patients (mean age, 64.9 years old; mean MMSE score, 17.7), 20 sex-matched Alzheimer’s disease (AD) patients
(mean age, 65.0 years old; mean MMSE score, 17.5), and 20 normal volunteers (mean age, 65.2 years old; mean MMSE score, 29.0)
underwent both [18F]FDG positron emission tomography and three-dimensional spoiled gradient echo MRI. Statistical parametric mapping was used
to conduct a VBM analysis of the morphologic data, which were compared voxel by voxel with the results of a similar analysis
of glucose metabolic data.
Results FTD patients showed decreased grey matter volume and decreased glucose metabolism in the frontal lobe and anterior temporal
lobe. In addition, there was a clear asymmetry in grey matter volume in FTD patients by the VBM analysis while the glucose
metabolic data showed little asymmetry. In AD patients, glucose metabolic reduction occurred in the bilateral posterior cingulate
gyri and parietal lobules while grey matter density decreased the least in the same patients.
Conclusion In FTD, metabolic and morphologic changes occur in the bilateral frontal lobe and temporal lobe with a limited asymmetry whereas
there was considerable discordance in the AD group. 相似文献
145.
Rosai-Dorfman disease presenting with multiple intracranial and intraspinal masses: a case report 总被引:2,自引:0,他引:2
Sato A Sakurada K Sonoda Y Saito S Kayama T Jokura H Yoshimoto T Nakazato Y 《No shinkei geka. Neurological surgery》2003,31(11):1199-1204
Rosai-Dorfman disease (RDD), a systemic histioproliferative disorder, was first described by Rosai and Dorfman in 1969. However, only 41 cases involving the central nervous system have been reported. The authors present a rare case of RDD with multiple intracranial and spinal lesions mimicking multiple meningioma. A 59-year-old woman was admitted to our hospital with a history of bilateral visual impairment. MRI demonstrated multiple central nervous system lesions in the suprasellar region, right temporal convexity, left frontal convexity, left cerebello-pontine angle and C5 level of the spinal cord. Preoperative neuro-imaging studies suggested multiple meningioma. Subtotal removal of the suprasellar lesion was performed, followed by gamma knife radiosurgery to the residual lesion and the other intracranial lesions. All intracranial lesions disappeared following gamma knife radiotherapy. The spinal lesion, however, was completely excised one year after the initial operation following the appearance of sensory disturbance. Both intracranial and spinal lesions were diagnosed as RDD on histological examination. No recurrences have been detected on MRI two years after the initial operation. Seeing the good results already achieved by surgical removal of RDD, this case suggests that the combination of surgery and gamma knife radiotherapy might improve further. 相似文献
146.
Kobayashi N Inamori M Fujita K Fujisawa T Fujisawa N Takahashi H Yoneda M Abe Y Kawamura H Shimamura T Kirikoshi H Kubota K Sakaguchi T Saito S Saubermann LJ Nakajima A 《Journal of Hepato-Biliary-Pancreatic Surgery》2008,15(2):169-177
Background/Purpose Intraductal papillary-mucinous neoplasms (IPMNs) of the pancreas have a favorable prognosis. However, invasive ductal carcinomas
of the pancreas show a rapid progression. The aim of this study was to investigate gene mutations in pure pancreatic juice
from IPMN patients and to define these genetic mutations in relation to the histopathological and clinical features of IPMNs.
Methods Twenty-two patients with IPMN, 21 patients with ductal carcinoma, and 20 patients with normal pancreas or chronic pancreatitis
were recruited for this study. We measured the main pancreatic duct’s largest diameter and the maximum size of a dilated branch
was assessed by ultrasonography or endoscopic ultrasonography. Pure pancreatic juice was collected and was investigated for
K-ras, p16, and p53 mutations.
Results Mutant K-ras gene was detected in 13 of the 22 patients (59.1%) with IPMNs. Different kinds of mutations were detected in the same patient
in 4 cases. In the 13 patients with mutant K-ras gene, the diameter of the most dilated part of the main pancreatic duct was 2–8 mm (average, 4.5 mm) and in 7 patients with
wild-type K-ras gene, the diameter was 2–5 mm (average, 2.7 mm). There was a significant difference in the diameter of the main pancreatic
duct between patients with and without the mutant K-ras gene (P = 0.0323).
Conclusions The incidence of K-ras mutation may be associated with the hypersecretion of mucin. 相似文献
147.
Horiuchi A Watanabe Y Doi T Sato K Yukumi S Yoshida M Yamamoto Y Sugishita H Kawachi K 《Surgical endoscopy》2008,22(12):2720-2723
Background Conversion rate to open surgery is higher for patients with acute cholecystitis than in those without acute cholecystitis.
We attempted to develop a laparoscopic subtotal cholecystectomy to decrease this conversion rate.
Methods From 2000 to 2005, laparoscopic cholecystectomy for acute cholecystitis was performed in 60 patients (22 women, 38 men). Patients
were divided into two groups: group A (2000 to 2002, n = 22) and group B (2003 to 2005, n = 38). When significant difficulty was encountered dissecting the gallbladder from its bed, we incised the gallbladder wall
leaving the posterior wall and cauterizing the remnant mucosa (subtotal cholecystectomy, SC-1). When dissection of the gall
bladder neck and triangle of Calot was difficult, the neck of the gallbladder was sutured despite clipping (SC-2).
Results Mean duration from onset of symptoms to operation was 55.3 ± 52.0 days. SC-1 was performed in 8 patients in group A and 18
patients in group B. SC-2 was performed in three patients in Group B. Conversion rate was 18.1% (4/22) in group A and 0% (0/38)
in group B, compared to 0.4% (1/221) for patients without acute cholecystitis. No complications were associated with ablated
gallbladder mucosa.
Conclusion Laparoscopic subtotal cholecystectomy offers safe and effective treatment for acute cholecystitis. The conversion rate in
group B is decreased by avoiding hazardous dissection of the cystic duct. 相似文献
148.
Kazuhiko Iwahashi Atsushi Omura Toshihiro Kawahira Masayoshi Okada 《General thoracic and cardiovascular surgery》2008,56(12):599-601
A 46-year-old man with anomalous origin of the left coronary artery from the pulmonary artery (Bland-White-Garland syndrome)
is reported. We successfully performed coronary artery bypass grafting with the use of bilateral internal thoracic arteries
and ligation of the anomalous left coronary artery. The patient was discharged from the hospital after an uneventful postoperative
course and postoperative coronary angiography, which revealed patent internal thoracic arteries and no leakage of blood flow
from the anomalous left coronary artery to the pulmonary artery. This surgical procedure is technically simple and useful
for adult patients with Bland-White-Garland syndrome. To our knowledge, this is one of only a few reports on coronary artery
bypass grafting with bilateral internal thoracic arteries as a treatment of Bland-White-Garland syndrome. 相似文献
149.
Koda K Yasuda H Suzuki M Yamazaki M Tezuka T Kosugi C Higuchi R Sugimoto M Hirano A Uemura S Tsuchiya H 《Nihon Geka Gakkai zasshi》2008,109(5):274-277
After low anterior resection for rectal cancer, approximately 50% of patients experience defecatory malfunction such as multiple evacuations, urgency, and soiling. Since the neorectum is constructed with the remaining colonic segment, it can only substitute for the rectum to a limited extent. A straight anastomosis is most frequently used when the rectal remnant is sufficient, such as in high anterior resection. When the height of anastomosis is close to the anal sphincter, a J-pouch, a side-to-end, or a transverse coloplasty pouch are constructed to achieve better postoperative bowel function. The advantage of J-pouch reconstruction is not only the increased volume but also may be decreased motility when compared with straight reconstruction. In terms of postoperative function, the side-to-end and transverse coloplasty pouch have both been reported to exhibit similar functional results to J-pouch reconstruction. To obtain optimal functional results, pouch reconstruction should be considered, especially when the height of anastomosis is at the levator plane. 相似文献
150.
Nojima H Cho A Yamamoto H Nagata M Takiguchi N Kainuma O Souda H Gunji H Miyazaki A Ikeda A Matsumoto I Asano T Ryu M Nihei N Maruoka M 《Journal of Hepato-Biliary-Pancreatic Surgery》2008,15(2):209-212
Gallbladder involvement in patients with renal cell carcinoma (RCC) is extremely rare. We present a report of a 61-year-old
man with a synchronous RCC metastasis to the gallbladder presenting as an intraluminal polypoid mass simulating primary gallbladder
carcinoma. Enhanced abdominal computed tomography demonstrated a well-enhanced polypoid lesion in the gallbladder. Intraoperative
rapid pathological examination of the gallbladder tumor showed clear cell-type cancerous cells. Microscopically, tumor cells
of both the resected kidney and gallbladder had round uniform nuclei, clear cytoplasm, and well-defined cytoplasmic borders,
forming alveolar patterns. Immunohistochemically, the tumor cells were negative for cytokeratin 7 (CK7) and carcinoembryonic
antigen (CEA), which is usually positive in primary clear cell carcinoma of the gallbladder. Therefore, the final diagnosis
was RCC with a synchronous gallbladder metastasis. 相似文献