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排序方式: 共有1419条查询结果,搜索用时 31 毫秒
81.
Relapsing polychondritis studied by computed tomography 总被引:1,自引:0,他引:1
Computed tomographic findings in a patient with relapsing polychondritis are described. Collapse of the cartilage of the nose and calcification in cartilages of the ears were clearly demonstrated. CT scanning was also helpful in evaluating the tracheobronchial tree for airway compromise, which could prove fatal in this condition. 相似文献
82.
83.
PURPOSE OF REVIEW: This review examines the biochemical parameters of early pregnancy failure and the role that biochemical markers have to play in the selection of patients for expectant management. RECENT FINDINGS: Earlier studies have concentrated on the role that human chorionic gonadotrophin and progesterone have to play in early pregnancy failure. Recent studies, however, have explored newer markers such as the inhibins and insulin growth factor binding proteins. Diagnostic models have now been created incorporating demographic, morphological, and biochemical parameters for the prediction of successful expectant management of early pregnancy failure. SUMMARY: Examining the role of newer biochemical markers in early pregnancy failure has led to an improved understanding of the mechanisms behind it. Incorporation of these newer markers into diagnostic models has aided selection of patients for whom expectant management is appropriate. 相似文献
84.
Clarke S Wakeley C Duddy J Sharif M Watt I Ellingham K Elson CJ Nickols G Kirwan JR 《Skeletal radiology》2004,33(10):588-595
Objective Plain X-ray is an imprecise tool for monitoring the subchondral bony changes associated with the development of knee osteoarthritis (OA). Our objective was to develop and validate a technique for assessing tibial subchondral bone density (BMD) in knee OA using dual energy X-ray absorptiometry (DXA).Design Patients with OA of at least one knee underwent DXA scanning of both knees. Regions of interest (ROI) were placed in the lateral and medial compartments of tibial subchondral bone. Weight-bearing plain X-rays and Te 99m scintiscans of both knees were obtained and scored.Results One hundred and twelve patients (223 knees) underwent DXA and radiography. Intra-observer CV% was 2.4% and 1.0% for the medial and lateral ROI respectively. Definite OA (Kellgren and Lawrence Grade 2, 3 or 4) was correlated with age-related preservation of subchondral BMD compared to radiographically normal knees. Raised BMD was also associated with subchondral sclerosis, and positive scintigraphy.Conclusion DXA may provide a safe, rapid and reliable means of assessing knee OA. Cross-sectional age-related subchondral tibial BMD loss is attenuated by knee OA.Work completed at Bristol Royal Infirmary, Bristol, BS2 8HW, UK 相似文献
85.
O'Brien TJ So EL Cascino GD Hauser MF Marsh WR Meyer FB Sharbrough FW Mullan BP 《Epilepsia》2004,45(4):367-376
PURPOSE: To determine the extent to which periictal subtraction single-photon emission computed tomography (SPECT) may improve detection and definition of the epileptogenic zone in patients with focal malformations of cortical development (MCDs). METHODS: Subtraction SPECT coregistered to magnetic resonance (MR) images (SISCOM) were constructed for 22 consecutive patients with focal MCDs who underwent periictal SPECT injection (18 ictal and four postictal). In the 17 patients who had epilepsy surgery, concordance between the site of SISCOM localization and site of surgical resection was determined by coregistration of SISCOM images with postoperative MRIs. RESULTS: SISCOM images were localizing in 19 (86%) patients, including eight of the 10 with nonlocalizing MRI. Concordance of SISCOM localization was 91% with MRI localization, 93% with scalp ictal EEG localization, and 100% with intracranial EEG localization. Eight patients whose SISCOM localization was concordant with the surgical resection site had lower postoperative seizure frequency scores (SFSs; p = 0.04) and greater postoperative improvement in SFSs (p = 0.05) than the nine patients whose SISCOM was either nonconcordant or nonlocalizing. On multiple regression analysis, a model combining SISCOM concordance with surgical resection site and extent of MRI lesion resection was predictive of postoperative SFS (R2 = 0.47; p = 0.03). CONCLUSIONS: Periictal subtraction SPECT using the SISCOM technique provides useful information for seizure localization in patients with focal MCDs, even when MRI is nonlocalizing. 相似文献
86.
Banerjee S Aslam N Woelfer B Lawrence A Elson J Jurkovic D 《BJOG : an international journal of obstetrics and gynaecology》2001,108(2):158-163
Objective To assess prospectively the ability of two multiparameter diagnostic models and their individual components to predict the outcome of early pregnancies which could not be identified on transvaginal ultrasound scan.
Design Prospective observational study.
Setting Dedicated early pregnancy unit in an inner city teaching hospital.
Population Women with a positive urine pregnancy test and clinical suspicion of early pregnancy complications.
Methods A full medical history, clinical examination and transvaginal ultrasound scan were carried out at the initial visit. When the location of the pregnancy could not be ascertained by ultrasound, serum beta-human chorionic gonadotrophin ( β -hCG) and progesterone levels were measured. All women were managed expectantly until either a normal pregnancy was visualised on scan; the pregnancy resolved spontaneously or intervention was required due to a worsening of clinical symptoms or non-declining β -hCG levels.
Main outcome measures Spontaneous resolution of pregnancy (i.e. cessation of symptoms and decline in serum β -hCG level to < 20 iu/L) without need for any active intervention.
Results Of the 104 women recruited, 72 (69%) pregnancies resolved spontaneously. Both multiparameter diagnostic models identified resolving pregnancies with positive predictive values ≥ 95% . Their performances were not significantly better compared with individual progesterone levels which achieved a positive predictive value of 97% using a cutoff level of 20 nmol/L.
Conclusion Serum progesterone measurement alone is as accurate as more complex diagnostic models for the prediction of successful expectant management in pregnancies of unknown location. 相似文献
Design Prospective observational study.
Setting Dedicated early pregnancy unit in an inner city teaching hospital.
Population Women with a positive urine pregnancy test and clinical suspicion of early pregnancy complications.
Methods A full medical history, clinical examination and transvaginal ultrasound scan were carried out at the initial visit. When the location of the pregnancy could not be ascertained by ultrasound, serum beta-human chorionic gonadotrophin ( β -hCG) and progesterone levels were measured. All women were managed expectantly until either a normal pregnancy was visualised on scan; the pregnancy resolved spontaneously or intervention was required due to a worsening of clinical symptoms or non-declining β -hCG levels.
Main outcome measures Spontaneous resolution of pregnancy (i.e. cessation of symptoms and decline in serum β -hCG level to < 20 iu/L) without need for any active intervention.
Results Of the 104 women recruited, 72 (69%) pregnancies resolved spontaneously. Both multiparameter diagnostic models identified resolving pregnancies with positive predictive values ≥ 95% . Their performances were not significantly better compared with individual progesterone levels which achieved a positive predictive value of 97% using a cutoff level of 20 nmol/L.
Conclusion Serum progesterone measurement alone is as accurate as more complex diagnostic models for the prediction of successful expectant management in pregnancies of unknown location. 相似文献
87.
Cholera toxin (CT), the enterotoxin of Vibrio cholerae, is a potent mucosal and systemic immunogen and adjuvant. The precise mechanism of the adjuvanticity of CT is poorly understood. Our previous work has showed that CT up-regulates B7.2, but not B7.1 expression on macrophages, and thus increases their co-stimulatory activity. In the current study, the effects of CT on macrophage co-stimulatory cytokine production were investigated. Bone marrow macrophages were generated by culturing bone marrow cells with macrophage colony-stimulating factor. CT treatment increased endotoxin-stimulated macrophage IL-10, IL-6, and IL-1beta production, whereas it decreased IL-12, TNF-alpha and nitric oxide production. Antibody blocking experiments showed that CT inhibition of IL-12 and TNF-alpha production was mediated by increased IL-10 production, in that addition of anti-IL-10 monoclonal antibody abrogated CT inhibition. The decrease in nitric oxide production was in turn secondary to inhibition of TNF-alpha production. Taken together, our study demonstrated that CT has differential effects on various macrophage co-stimulatory cytokines, effects that are likely to contribute to its adjuvanticity. 相似文献
88.
Belinson JL Pretorius RG Zhang WH Wu LY Qiao YL Elson P 《Obstetrics and gynecology》2001,98(3):441-444
OBJECTIVE: To estimate the sensitivity and specificity of visual inspection using acetic acid as a primary screen for cervical intraepithelial neoplasia (CIN). METHODS: Visual inspection was done on 1997 women aged 35-45 years in a screening trial in rural China. Each women had colposcopy and at least five cervical biopsies (directed biopsy of lesions, one biopsy at 2, 4, 8, or 10 o'clock at the squamocolumnar junction in each normal quadrant, and an endocervical curettage). RESULTS: Forty-three women had biopsy-proven CIN II, 31 had CIN III, and 12 had invasive cancer. In two women only the endocervix was positive (one with CIN II and one with CIN III). Visual inspection yielded normal results in 1445 women (72%), low-grade intraepithelial neoplasia in 525 (26%), high-grade in 21 (1%), and cancer in six (0.3%). With abnormal visual inspection defined as low-grade intraepithelial neoplasia or worse, the sensitivity for detecting biopsy proven CIN II or worse was 71% (61 of 86, 95% confidence interval [CI] 60%, 80%); the specificity was 74% (1420 of 1911, 95% CI 72%, 76%); the sensitivity was 65% for smaller lesions (37 of 57, 95% CI 51%, 77%), and 89% for larger lesions (24 of 27, 95% CI 71%, 98%) (P =.03). CONCLUSION: The sensitivity of visual inspection equaled or exceeded reported rates for conventional cervical cytology. Visual inspection and colposcopy have similar specificity profiles for CIN II and greater. The benefit of an inexpensive point-of-care diagnosis and treatment algorithm will be a powerful incentive to pursue visual inspection for cervical cancer screening in developing countries. 相似文献
89.
Elson A 《Oncogene》1999,18(52):7535-7542
Accurate phosphorylation of tyrosine residues in proteins plays a central role in regulation of cellular function. Although connections between aberrant tyrosine kinase activity and malignancy are well-established, significantly less is known about the roles of protein tyrosine phosphatases (PTPases) in tumorigenesis. We have previously shown that the transmembranal form of PTPase Epsilon (PTPepsilon) is upregulated in mouse mammary tumors initiated specifically by ras or neu, suggesting that PTPepsilon may play a role in transformation by these two oncogenes. In order to test this notion in vivo, we created transgenic mice that express elevated levels of PTPepsilon in their mammary epithelium by use of the MMTV promoter/enhancer. Following several cycles of pregnancy female MMTV-PTPepsilon mice uniformly developed pronounced and persistent mammary hyperplasia which was accompanied by residual milk production. Solitary mammary tumors were often detected secondary to mammary hyperplasia. The sporadic nature of the tumors, the long latency period prior to their development, and low levels of transgene expression in the tumors indicate that PTPepsilon provides a necessary, but insufficient, signal for oncogenesis. The results provide genetic evidence that PTPepsilon plays an accessory role in production of mammary tumors in a manner consistent with its upregulation in mammary tumors induced by ras or neu. 相似文献
90.