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71.
Criteria for the diagnosis of serrated colorectal lesions (hyperplastic polyp, sessile serrated adenoma without or with dysplasia—which we called mixed polyp—and traditional serrated adenoma) for which consensus has been reached should be validated for applicability in daily practice in terms of inter-observer reproducibility and their association with clinical features and (epi)genetic events. A study set was created from a consecutive series of colorectal polyps (n?=?1,926) by selecting all sessile serrated adenomas, traditional serrated adenomas and mixed polyps. We added consecutive series of hyperplastic polyps, classical adenomas and normal mucosa samples for a total of 200 specimens. With this series, we conducted an inter-observer study, encompassing ten pathologists with gastrointestinal pathology experience from five European countries, in three rounds in which all cases were microscopically evaluated. An assessment of single morphological criteria was included, and these were correlated with clinical parameters and the mutation status of KRAS, BRAF and PIK3CA and the methylation status of MLH1. Gender, age and localisation were significantly associated with certain types of lesions. Kappa statistics revealed moderate to good inter-observer agreement for polyp classification (κ = 0.56 to 0.63), but for single criteria, this varied considerably (κ = 0.06 to 0.82). BRAF mutations were frequently found in hyperplastic polyps (86 %, 62/72) and sessile serrated adenomas (80 %, 41/51). KRAS mutations occurred more frequently in traditional serrated adenomas (78 %, 7/9) and less so in classical adenomas (20 %, 10/51). Single morphological criteria for sessile serrated adenomas showed significant correlation with BRAF mutation (all p?≤?0.001), and those for classical adenomas or traditional serrated adenoma correlated significantly with KRAS mutation (all p?<?0.001). Therefore, single well-defined morphological criteria are predictive for genetic alterations in colorectal polyps.  相似文献   
72.
73.
Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an established treatment for advanced Parkinson's disease (PD) with disabling motor complications. However, stimulation may be beneficial at an earlier stage of PD when motor fluctuations and dyskinesia are only mild and psychosocial competence is still maintained. The EARLYSTIM trial was conducted in patients with recent onset of levodopa-induced motor complications (≤3 years) whose social and occupational functioning remained preserved. This is called ‘early’ here. The study was a randomized, multicenter, bi–national pivotal trial with a 2 year observation period. Quality of life was the main outcome measure, and a video-based motor score was a blinded secondary outcome of the study. Motor, neuropsychological, psychiatric and psychosocial aspects were captured by established scales and questionnaires. The patient group randomized here is the earliest in the disease course and the youngest recruited in controlled DBS trials so far. The methodological innovation for DBS-studies of this study lies in novel procedures developed and used for monitoring best medical treatment, neurosurgical consistency, best management of stimulation programming, blinded video assessment of motor disability, and prevention of suicidal behaviors.  相似文献   
74.
Aim: The study aims to provide objective data for the displacement of titanium screw implants in trabecular bone specimens. One hundred Semados implants (Bego, Bremen, Germany) were inserted in bovine type IV bone specimens. All implants had a diameter of 3.75 mm; 50 implants had a length of 8.5 mm and 50 implants had a length of 15 mm. Insertion torque was determined at intervals of 10, 20, and 30 Ncm. Implants were loaded horizontally with 10, 20, and 30 N for 2 seconds. An indicator strip was attached to the implant abutment to allow direct observation of implant movement relative to the bone surface. Horizontal displacement was assessed with an accuracy of measurement of 10 µm. Seven implants got lost by visible loosening. Degree of displacement was subject to evaluation with all others. Those implants showed a mean displacement of 59 µm for 10 N (n = 100), 173 µm for 20 N (n = 99), and 211 µm for 30 N (n = 93). The mean displacement of 15‐mm implants (16, 37, 51 µm) was significantly lower compared with 8.5‐mm implants (103, 311, 396 µm) corresponding to 10, 20, and 30 N as lateral loads. Conclusions: Displacement of screw implants in trabecular bone can be detected and visualized using commercially available endoscopes with a high magnification. A lateral load of 20 N indicates a mean displacement of over 100 µm and therefore results in a critical displacement.  相似文献   
75.
Introduction : Peritoneal carcinomatosis represents a clinical condition with a limited perspective concerning long term survival. The combination of surgical cytoreduction and hyperthermic intraperitoneal chemotherapy (HIPEC) represents a complex multimodal therapeutic management concept with promising results for prolongation of survival. For the identification of pitfalls during implementation of the HIPEC procedure into clinical practice an observational study was conducted.

Methods : Between 2005 and 2009 data from all patients treated with cytoreductive surgery and HIPEC for peritoneal carcinomatosis was prospectively collected and analysed.

Results : During the observational interval a total of 42 patients underwent surgical treatment for peritoneal carcinomatosis. In 34 patients the complete procedure with surgical cytoreduction and HIPEC was performed. Perioperative mortality (6%) and morbidity (35%) was similar to other reported series. Twenty-five patients (76%) survived the 18 months follow-up period after complete procedure.

Conclusion : The multimodal therapeutic treatment concept of surgical cytoreduction and following HIPEC leads to promising results for patients suffering from peritoneal carcinomatosis. However this treatment concept is afflicted with a relevant risk of postoperative complications.  相似文献   
76.
77.
Published literature on fracture in dialysis patients seldom addressed the effect of co‐morbidity and malnutrition. In this study, we reported the incidence and risk factors for fracture in peritoneal dialysis patients. Peritoneal dialysis patients who had fractures between 2006 and 2011 were recruited. Demographic data, details of fracture, Charlson Co‐morbidity Index (CCI) and biochemical parameters were also collected. Non‐fracture controls, matched for age, gender and duration of dialysis, were also recruited at ratio 1:1 for fracture risk analysis. The incidence of fracture was 1 in 37 patient‐years. The commonest site of fracture was neck of femur (n = 16, 55.2%). Twenty‐four patients (82.8%) developed fracture after slip and fall injury. Eight out of 17 self‐ambulatory patients (47.1%) became non‐ambulatory after fracture. Infection was the commonest complication during hospitalization. Univariant analysis demonstrated high CCI (P = 0.001), hypoalbuminaemia (P < 0.001), loss of self autonomy (P = 0.006) and non‐ambulatory state (P = 0.011) significantly associated with increased fracture risk. However, only CCI (odds ratio (OR) 1.373, P = 0.028) and albumin (OR 0.893, P = 0.025) increased fracture risk significantly on multivariant analysis. Bone profile and parathyroid hormone were not significant risk factors. To conclude, fracture associated with adverse outcome in peritoneal dialysis patients. High CCI score and hypoalbuminaemia significantly increase risk of fracture.  相似文献   
78.

Background

Despite significant improvements in perioperative mortality as well as response rates to multimodality treatment, results after surgical resection of pancreatic adenocarcinoma with respect to long-term outcomes remain disappointing. Patient recruitment for prospective international trials on adjuvant and neoadjuvant regimens is challenging for various reasons. We set out to assess the preconditions and potential to perform perioperative trials for pancreatic cancer within a well-established Austrian nationwide network of surgical and medical oncologists (Austrian Breast & Colorectal Cancer Study Group).

Methods

From 2005 to 2010 five high-volume centers and one medium-volume center completed standardized data entry forms with 33 parameters (history and patient related data, preoperative clinical staging and work-up, surgical details and intraoperative findings, postoperative complications, reinterventions, reoperations, 30-day mortality, histology, and timing of multimodality treatment). Outside of the study group, in Austria pancreatic resections are performed in three “high-volume” centers (>10 pancreatic resections per year), three “medium-volume” centers (5–10 pancreatic resections per year), and the rest in various low-volume centers (<5 pancreatic resections per year) in Austria. Nationwide data for prevalence of and surgical resections for pancreatic adenocarcinoma were contributed by the National Cancer Registry of Statistics of Austria and the Austrian Health Institute.

Results

In total, 492 consecutive patients underwent pancreatic resection for ductal adenocarcinoma. All postoperative complications leading to hospital readmission were treated at the primary surgical department and documented in the database. Overall morbidity and pancreatic fistula rate were 45.5 % and 10.1 %, respectively. Within the entire cohort there were 9.8 % radiological reinterventions and 10.4 % reoperations. Length of stay was 16 days in median (0–209); 12 of 492 patients died within 30 days after operation, resulting in a 30-day mortality rate of 2.4 %. Seven of the total 19 deaths (36.8 %) occurred after 30 days, during hospitalization at the surgical department, resulting in a hospital mortality rate of 3.9 % (19/492). With a standardized histopathological protocol, there were 70 % (21/30) R0 resections, 30 % (9/30) R1 resections, and no R2 resections in Vienna and 62.7 % (32/51) R0 resections, 35.3 % (18/51) R1 resections, and 2 % (1/51) R2 resections in Salzburg. Resection margin status with nonstandardized protocols was classified as R0 in 82 % (339/411), R1 in 16 % (16/411), and R2 in 1.2 % (5/411). Perioperative chemotherapy was administered in 81.1 % of patients (8.3 % neoadjuvant; 68.5 % adjuvant; 4.3 % palliative); chemoradiotherapy (1.6 % neoadjuvant; 3 % adjuvant; 0.2 % palliative), in 4.9 % of patients. The six centers that contributed to this registry initiative provided surgical treatment to 40 % of all Austrian patients, resulting in a median annual recruitment of 85 (51–104) patients for the entire ABCSG-group and a median of 11.8 (0–38) surgeries for each individual department.

Conclusions

Surgical quality data of the ABCSG core pancreatic group are in line with international standards. With continuing centralization the essential potential to perform prospective clinical trials for pancreatic adenocarcinoma is given in Austria. Several protocol proposals aiming at surgical and multimodality research questions are currently being discussed.  相似文献   
79.

Introduction

The median survival of patients with glioblastoma multiforme (astrocytoma grade 4) remains less than 18 months despite radical surgery, radiotherapy and systemic chemotherapy. Surgical implantation of chemotherapy eluting wafers into the resection cavity has been shown to improve length of survival but the current licensed therapy has several drawbacks. This paper investigates in vivo efficacy of a novel drug eluting paste in glioblastoma.

Methods

Poly(lactic-co-glycolic acid)/poly(ethylene glycol) (PLGA/PEG) self-sintering paste was loaded with the chemotherapeutic agent etoposide and delivered surgically into partially resected tumours in a flank murine glioblastoma xenograft model.

Results

Surgical delivery of the paste was successful and practical, with no toxicity or surgical morbidity to the animals. The paste was retained in the tumour cavity, and preliminary results suggest a useful antitumour and antiangiogenic effect, particularly at higher doses. Bioluminescent imaging was not affected significantly by the presence of the paste in the tumour.

Conclusions

Chemotherapy loaded PLGA/PEG paste seems to be a promising technology capable of delivering active drugs into partially resected tumours. The preliminary results of this study suggest efficacy with no toxicity and will lead to larger scale efficacy studies in orthotopic glioblastoma models.  相似文献   
80.
To define an optimal regimen for mobilizing and collecting peripheral blood progenitor cells (PBPC) for use in allogeneic transplantation, we evaluated the kinetics of mobilization by filgrastim (recombinant met- human granulocyte colony-stimulating factor [r-metHuG-CSF]) in normal volunteers. Filgrastim was injected subcutaneously for up to 10 days at a dose of 3 (n = 10), 5 (n = 5), or 10 micrograms/kg/d (n = 15). A subset of volunteers from each dose cohort underwent a 7L leukapheresis on study day 6 (after 5 days of filgrastim). Granulocyte-macrophage colony-forming cell (GM-CFC) numbers in the blood were maximal after 5 days of filgrastim; a broader peak was evident for CD34+ cells between days 4 and 6. The 95% confidence intervals (CI) for mean number of PBPC per milliliter of blood in the three dose cohorts overlapped on each study day. However, on the peak day, CD34+ cells were significantly higher in the 10 micrograms/kg/d cohort than in a pool of the 3 and 5 micrograms/kg/d cohorts. Mobilization was not significantly influenced by volunteer age or sex. Leukapheresis products obtained at the 10 micrograms/kg/d dose level contained a median GM-CFC number of 93 x 10(4)/kg (range, 50 x 10(4)/kg to 172 x 10(4)/kg). Collections from volunteers receiving lower doses of filgrastim contained a median GM- CFC number of 36 x 10(4)/kg (range, 5 x 10(4)/kg to 204 x 10(4)/kg). The measurement of CD34+ cells per milliliter of blood on the day of leukapheresis predicted the total yield of PBPC in the leukapheresis product (r = .87, P < .0001). Assuming a minimum GM-CFC requirement of 50 x 10(4)/kg (based on our experience with autologous PBPC transplantation), all seven leukapheresis products obtained at the 10 micrograms/kg/d dose level were potentially sufficient for allogeneic transplantation purposes. We conclude that in normal donors, filgrastim 10 micrograms/kg/d for 5 days with a single leukapheresis on the following day is a highly effective regimen for PBPC mobilization and collection. Further studies are required to determine whether PBPC collected with this regimen reliably produce rapid and sustained engraftment in allogeneic recipients.  相似文献   
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