全文获取类型
收费全文 | 194810篇 |
免费 | 1851篇 |
国内免费 | 93篇 |
专业分类
耳鼻咽喉 | 1255篇 |
儿科学 | 6926篇 |
妇产科学 | 3222篇 |
基础医学 | 18738篇 |
口腔科学 | 2126篇 |
临床医学 | 13584篇 |
内科学 | 35474篇 |
皮肤病学 | 1021篇 |
神经病学 | 17934篇 |
特种医学 | 9850篇 |
外科学 | 32264篇 |
综合类 | 2400篇 |
一般理论 | 1篇 |
预防医学 | 18759篇 |
眼科学 | 3224篇 |
药学 | 10899篇 |
中国医学 | 647篇 |
肿瘤学 | 18430篇 |
出版年
2022年 | 194篇 |
2021年 | 331篇 |
2020年 | 210篇 |
2019年 | 281篇 |
2018年 | 22184篇 |
2017年 | 17562篇 |
2016年 | 19752篇 |
2015年 | 1204篇 |
2014年 | 1169篇 |
2013年 | 1287篇 |
2012年 | 7747篇 |
2011年 | 21861篇 |
2010年 | 19290篇 |
2009年 | 11909篇 |
2008年 | 20238篇 |
2007年 | 22523篇 |
2006年 | 1496篇 |
2005年 | 3063篇 |
2004年 | 4233篇 |
2003年 | 5087篇 |
2002年 | 3291篇 |
2001年 | 1146篇 |
2000年 | 1303篇 |
1999年 | 920篇 |
1998年 | 469篇 |
1997年 | 404篇 |
1996年 | 310篇 |
1995年 | 240篇 |
1994年 | 240篇 |
1993年 | 180篇 |
1992年 | 560篇 |
1991年 | 568篇 |
1990年 | 597篇 |
1989年 | 538篇 |
1988年 | 460篇 |
1987年 | 442篇 |
1986年 | 428篇 |
1985年 | 417篇 |
1984年 | 249篇 |
1983年 | 203篇 |
1982年 | 113篇 |
1980年 | 97篇 |
1979年 | 181篇 |
1978年 | 118篇 |
1977年 | 105篇 |
1974年 | 97篇 |
1973年 | 96篇 |
1970年 | 128篇 |
1969年 | 111篇 |
1968年 | 102篇 |
排序方式: 共有10000条查询结果,搜索用时 20 毫秒
991.
Takuya Nagata Yutaka Shimada Takeshi Miwa Isaya Hashimoto Hirofumi Kojima Tomoyuki Okumura Kazuhiro Tsukada 《Surgery today》2016,46(5):575-582
Purpose
Several video-assisted and robotic surgery techniques have been reported for resection of the thyroid and parathyroid glands. Our institute has started performing endoscopic thyroidectomy using the Lap-protector and E·Z-access system, referred to as E·Z-access using video-assisted neck surgery (EZ-VANS). In this report, we evaluate the safety and efficacy of this technique.Methods
From January 2007 to September 2014, 110 patients underwent resection of a primary thyroid tumor, 73 who underwent a cervical collar incision (the Open group) and 37 underwent EZ-VANS (the EZ-VANS group).Results
The average operating time was 159 and 172 min in the Open group and EZ-VANS group, respectively; the amount of blood loss was 46.5 and 54.7 ml, respectively; and the length of hospital stay after surgery was 4.3 and 5.2 days, respectively, with no significant differences observed between the two groups. The learning curve for the EZ-VANS technique was shorter than for open surgery.Conclusions
We confirmed that the EZ-VANS technique is a safe and useful method for resection of benign and early malignant thyroid tumors.992.
Harunobu Sato Kunihiro Toyama Yoshikazu Koide Shinji Ozeki Kouhei Hatta Kotaro Maeda 《Surgery today》2016,46(7):860-871
Purpose
We devised a simple dichotomous classification system and showed sufficient reproducibility to indicate treatment strategies for peritoneal metastasis of colorectal cancer.Methods
We included 67 patients with peritoneal metastasis of colorectal cancer and classified them according to the largest lesion size, number of lesions and number of regional peritoneal metastases. The oncological data were recorded and compared.Results
According to the univariate analyses, the prognoses were significantly better in patients with ≤3 disseminated lesions than in those with ≥4, and in patients with disseminated lesions in only one region than in those with ≥2 lesions. A multivariate analysis showed that primary tumor resection and the presence of peritoneal metastases in only one region were favorable factors for the patient survival. Patients with disseminated lesions in only one region (localized group) and those with nonlocalized lesions had three-year survival rates of 45.6 and 12.2 %, respectively. Finally, primary tumor resection improved the prognoses in both the localized and nonlocalized groups.Conclusions
Colorectal cancer patients were categorized into localized and nonlocalized groups according to the number of regions with peritoneal metastasis, and significant prognostic associations were demonstrated. Subsequent analyses of the oncological data suggested that primary tumor resection contributes to an improved prognosis in all patients with synchronous peritoneal metastases.993.
Takekazu Iwata Kaoru Nagato Takahiro Nakajima Hidemi Suzuki Shigetoshi Yoshida Ichiro Yoshino 《Surgery today》2016,46(8):877-886
Postoperative atrial fibrillation (POAF), the most frequent arrhythmia after pulmonary resection, is a cause of both morbidity and mortality. Being able to predict the risk of POAF before surgery would help us evaluate the surgical risk and plan prophylaxis. We investigated the reported preoperative risk factors associated with the incidence of POAF and found that the recommended predictive factors were quite variable. Therefore, we evaluated the previously reported preoperative risk factors for POAF using our institutional data. We discuss our findings in this short review. Male gender, resected lung volume, brain natriuretic peptide (BNP), and left ventricular early transmitral velocity/mitral annular early diastolic velocity (E/e′) calculated by echocardiography were suggested as independent predictors for POAF, but the predictive values of each individual parameter were not high. The lack of definitive predictors for POAF warrants further investigations by gathering the reported knowledge, to establish an effective preoperative examination strategy. 相似文献
994.
Simon Dagenais Shawn Garbedian Eugene K. Wai 《Clinical orthopaedics and related research》2009,467(3):623-637
Hip osteoarthritis is a common cause of musculoskeletal pain in older adults and may result in decreased mobility and quality of life. Although the presentation of hip osteoarthritis varies, surgical management is required when the disease is severe, longstanding, and unresponsive to nonoperative treatments. For stakeholders to plan for the expected increased demand for surgical procedures related to hip osteoarthritis, including arthroplasty, it is important to first understand its prevalence. We conducted a systematic review by searching MEDLINE® and EMBASE to identify recent English language articles reporting on the prevalence of radiographic primary hip osteoarthritis in the general adult population; references including studies and primary studies from previous systematic reviews were also searched. This strategy yielded 23 studies reporting 39 estimates of overall prevalence ranging from 0.9% to 27% with a mean of 8.0% and a standard deviation of 7.0%. Heterogeneity was noted in study populations, eligibility criteria, age and gender distribution, type of radiographs, and method of diagnosis. Although the association between radiographic hip osteoarthritis and the need for eventual surgical management is still unclear, this study supports assertions that hip osteoarthritis is a prevalent condition whose treatment will continue to place important demands on health services. 相似文献
995.
Bal Krishna Ojha Mazhar Husain Manu Rastogi Anil Chandra Ashish Chugh Nuzahat Husain 《Acta neurochirurgica》2009,151(7):843-847
Objective This is the first report of the simultaneous combined use of trans-sphenoidal and trans-ventricular-endoscopic route for decompression
of a giant pituitary adenoma.
Method A 38 year old man presented to us with symptoms of raised intracranial pressure along with visual and hypothalamic disturbances.
The CT scan revealed destruction of the sella by a large (5 × 3.5 × 2.5 cm) well defined enhancing mass in the sella and suprasellar
region extending laterally up to the cavernous sinuses and both carotid arteries and superiorly into the lumen of the 3rd
ventricle producing obstructive hydrocephalus. On T2WI of the non-contrast MRI scan the mass was iso-intense to grey matter
suggesting the possibility of a firm nature of the adenoma. The tumour was first approached by the standard trans-sphenoidal
route and as predicted from the pre-operative MRI, the tumour was found to be firm and not amenable to suction. After decompression
of the intra-sellar part of the tumour, the intracranial pressure was raised in an attempt to make the remainder of the tumour
descend into the sella but without success. The suprasellar part of the tumour was then simultaneously addressed via a trans-ventricular-endoscopic
route but the firm tumour did not yield to endoscopic instruments viz. biopsy forceps, angiographic catheter and electrosurgical
probes. It was then gently pushed down towards the sella and decompressed piecemeal by using trans-sphenoidal instruments.
The sellar cavity was reconstructed using fat, fascia lata graft and a piece of septal bone.
Results Post-operatively, the patient showed a remarkable improvement of his symptoms of raised intracranial pressure, hypothalamic
dysfunction and visual disturbances. Follow-up imaging at 2 months and 1 year, did not show any residual or recurrent tumour.
Conclusions This novel technique of the combined trans-sphenoidal and simultaneous trans-ventricular-endoscopic approach is a viable option
for patients with giant fibrous pituitary adenoma when the tumour is not yielding to the trans-sphenoidal route alone. 相似文献
996.
Objective To assess the main characteristics of late relapsing malignant germ cell tumors (MGCTs). These tumors are rare and occur by
definition 2 years or later after successful treatment.
Methods We present relevant literature on relapsing MGCT in order to highlight the following issues: incidence, impact of initial
treatment on the subsequent risk of late relapse, treatment, and survival.
Results A pooled analysis of 5,880 patients with MGCT revealed late relapses in 119 of 3,704 (3.2%) and in 31 of 2,176 (1.4%) patients
with non-seminoma and seminoma, respectively. The retroperitoneal space is the predominant site of relapse in both histological
types. The initial treatment is important for the risk and localization of late relapses. Patients with single site teratoma
are usually cured by surgery alone, whereas viable MGCT or teratoma with malignant transformation may require multimodal treatment
with chemo- and/or radiotherapy as well as surgery. Surgery is the most important part in the treatment of late relapses.
Salvage chemotherapy should, if feasible, be based on a representative biopsy. Five-year cancer-specific survival is above
50% in the recent large series and reaches 100% in case of single site teratoma.
Conclusions Treatment of late relapsing MGCT patients is challenging and should be performed in experienced centers only. Referral of
late relapsing patients to high-volume institutions ensures the best chances of cure and enables multimodal treatment, and
contributes to increased knowledge of tumor biology as well experience with the clinical course of these patients. 相似文献
997.
Kentaro Umezu Satoshi Saito Kenji Yamazaki Akihiko Kawai Hiromi Kurosawa 《General thoracic and cardiovascular surgery》2009,57(4):197-202
Purpose There has been a changing preference for bioprosthetic valves over mechanical valves in dialysis patients, but there is still
much controversy. We reviewed our 17-year experience and assessed the influence of prosthesis choice.
Methods From 1990 to 2007, a total of 63 consecutive dialysis patients who underwent valvular surgery (64 operations including one
reoperation) at our hospital were retrospectively reviewed. The mean age of the patients was 58.3 ± 9.0 years. The reasons
for dialysis were glomerulonephritis (n = 32) and diabetes (n = 10). The major preoperative diagnosis was aortic stenosis (n = 44). The surgical procedures included aortic valve replacement (n = 44), mitral valve replacement (n = 7), double valvular replacement (n = 7), and mitral valve repair (n = 5). Prostheses for valve replacement were mechanical valves (n = 37) or bioprosthetic valves (n = 22). Follow-up was accomplished in 95.2%, and the mean follow-up period was 49 months.
Results Actuarial survivals at 1, 5, and 10 years were 85%, 64%, and 45% respectively. Freedom from cardiovascular events at 1 and
5 years was 61% and 41%, respectively. Mechanical valve patients had significantly higher early mortality than bioprosthetic
valve patients (P = 0.03). However, both mechanical and bioprosthetic valve patients had similar survival and event-free rates (P = 0.87 and P = 0.27, respectively) in the midterm results. The mechanical group had a higher rate of bleeding events. There was no structural
valve deterioration up to the 5-year follow-up.
Conclusion The choice of prosthesis did not influence the surgical outcome except for early mortality. Careful consideration of preventive
measures against bleeding is important, and prosthesis selection should be based on the patient’s profile as well as the criteria
for nondialysis patients. 相似文献
998.
Seung-Yeob Yang Dong Gyu Kim Hyun-Tai Chung Sun Ha Paek Jae Hyo Park Dae Hee Han 《Acta neurochirurgica》2009,151(2):113-124
Background Radiosurgery is an effective treatment option for patients with small to medium sized arteriovenous malformations. However,
it is not generally accepted as an effective tool for larger (>14 cm3) arteriovenous malformations because of low obliteration rates. The authors assessed the applicability and effectiveness
of radiosurgery for large arteriovenous malformations.
Method We performed a retrospective study of 46 consecutive patients with more than 14 ml of arteriovenous malformations who were
treated with radiosurgery using a linear accelerator and gamma knife (GK). They were grouped according to their initial clinical
presentation—17 presented with and 29 without haemorrhage. To assess the effect of embolization, these 46 patients were also
regrouped into two subgroups—25 with and 21 without preradiosurgical embolization. Arteriovenous malformations found to have
been incompletely obliterated after 3-year follow-up neuroimaging studies were re-treated using a GK.
Findings The mean treatment volume was 29.5 ml (range, 14.0–65.0) and the mean marginal dose was 14.1 Gy (range, 10.0–20.0). The mean
clinical follow-up periods after initial radiosurgery was 78.1 months (range, 34.0–166.4). Depending on the results of the
angiography, 11 of 33 patients after the first radiosurgery and three of four patients after the second radiosurgery showed
complete obliteration. Twenty patients received the second radiosurgery and their mean volume was significantly smaller than
their initial volume (P = 0.017). The annual haemorrhage rate after radiosurgery was 2.9% in the haemorrhage group (mean follow-up 73.3 months) and
3.1% in the nonhaemorrhage group (mean follow-up 66.5 months) (P = 0.941). Preradiosurgical embolization increased the risk of haemorrhage for the nonhaemorrhage group (HR, 28.03; 95% CI,
1.08–6,759.64; P = 0.039), whereas it had no effect on the haemorrhage group. Latency period haemorrhage occurred in eight patients in the
embolization group, but in no patient in the nonembolization group (P = 0.004).
Conclusions Radiosurgery may be a safe and effective arteriovenous malformation treatment method that is worth considering as an alternative
treatment option for a large arteriovenous malformation. 相似文献
999.
1000.
In this prospective study, our aim was to compare the clinical outcome of posterior lumbar interbody fusion (PLIF) and posterolateral fusion (PLF) in spondylolisthesis. A total of 138 patients with spondylolisthesis were randomly assigned to two groups: those operated on with pedicle screw fixation and posterior lumbar interbody fusion by autografting (PLIF), and those operated on with pedicle screw fixation and posterolateral fusion by autografting (PLF). The patients were followed-up for four years. Clinical evaluation was carried out using the Oswestry disability index (ODI) and pain index (VAS). Radiography was performed preoperatively and postoperatively to assess the fusion. Both surgical procedures were effective, but the PLF group showed more complications related to hardware biomechanics. There was no significant statistical difference in clinical and functional outcome in the two groups. The PLIF group presented a better fusion rate than the PLF group. 相似文献