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71.
A general reaction of glycosyl cyanides with liquid hydrogen sulfide in the presence of 4-dimethylaminopyridine to provide the corresponding glycosylthiocarboxamides is described. These glycosylthiocarboxamides were utilized as the precursors for the synthesis of 2-D-ribofuranosylthiazole-4-carboxamide and 2-beta-D-ribofuranosylthiazole-5-carboxamide (23). The structural modification of 2-beta-D-ribofuranosylthiazole-4-carboxamide (12) into 2-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)thiazole-4-carboxamide (15), 2-beta-D-ribofuranosylthiazole-4-thiocarboxamide (17), and 2-(5-deoxy-beta-D-ribofuranosyl)thiazole-4-carboxamide (19) is also described. These thiazole nucleosides were tested for in vitro activity against type 1 herpes virus, type 3 parainfluenza virus, and type 13 rhinovirus and an in vivo experiment was run against parainfluenza virus. They were also evaluated as potential inhibitors of purine nucleotide biosynthesis. It was shown that the compounds (12 and 15) which possessed the most significant antiviral activity were also active inhibitors (40-70%) of guanine nucleotide biosynthesis.  相似文献   
72.
Metastatic pancreatic ductal adenocarcinoma and primary cholangiocarcinoma are morphologically very similar and, therefore, challenging to distinguish in liver biopsies. The distinction is important because surgical management and prognosis differ significantly. Several immunohistochemical markers have been evaluated to aid this diagnosis, but aside from N-cadherin, which labels cholangiocarcinoma, few provide the combination of good sensitivity and specificity. Our laboratory recently developed the novel monoclonal antibody human pancreatic cancer fusion #2 (HPC2) that recognizes pancreatic cancer. We hypothesized that the combination of our new marker and N-cadherin can assist in distinguishing metastatic pancreatic cancer from cholangiocarcinoma. We immunostained resections of 60 pancreatic ductal adenocarcinomas and 31 cholangiocarcinomas for the HPC2 and N-cadherin antigens. We also stained 24 gallbladder adenocarcinomas, 11 ampullary adenocarcinomas, and 10 metastatic colonic adenocarcinomas to the liver. Sections were independently scored by 2 pathologists with good agreement using both markers (κ statistics, 0.62-0.64; P < .0001). HPC2 was observed in 80% of pancreatic cancers (48/60), 82% of ampullary (9/11), and 32% (10/31) of cholangiocarcinomas. N-cadherin stained 27% (16/60) of the pancreas cases and 58% (18/31) of the cholangiocarcinomas. Gallbladder and colon cancers were usually double negative (18/24 and 8/10, respectively). Each marker provided significant likelihood ratios to separate pancreatic cancer (HPC2, 2.48 [1.46-4.19]; P < .0001) from cholangiocarcinoma (N-cadherin, 2.17 [1.3-3.64]; P < .01). The combination of both markers provided even better specificity and positive likelihood ratios. We conclude that HPC2 and N-cadherin significantly improve accurate classification of pancreatic cancer and cholangiocarcinoma.  相似文献   
73.
Both name and source information provide a context for the perceptual evaluation of odorants (Herz, J Exp Psychol 132(4): 595?C606, 2003) that may also affect memory (Lyman and McDaniel, J Exp Psychol 16(4): 656?C664, 1986). The current study asked whether appropriate information about the context in which an odor source is found would affect short-term memory for the odor. Fifty-four participants were presented with pairs of olfactory stimuli and visual contextual information that either matched each other or did not. There were two types of visual stimuli, either a pictorial representation of a contextual location for an odor source or a written representation of the name of that location. Stimulus presentation was followed by a verbal interference task (Peterson and Peterson, J Exp Psychol 58: 193?C198, 1959). A recognition test for the olfactory stimuli conducted immediately afterwards revealed that participants who had been presented with visual representations of non-matching odor source contexts were more likely to falsely remember odors appropriate to the visual context. These findings suggest that participants either relied heavily on encoding of the visually presented source contextual information, to the detriment of memory, for olfactory stimuli or suffered from the semantic-based memory error of misattribution.  相似文献   
74.
Children and adolescents with maltreatment-related posttraumatic stress disorder (PTSD) exhibit smaller intracranial tissue volume than controls. Linear relationships have also been observed between intracranial tissue volume and the age of maltreatment onset. The authors explored associations among adult PTSD, early trauma, and cerebral volumes in 99 combat veterans. A bone-based estimate of cranial volume was developed to adjust for variation in body size. Posttraumatic stress disorder was not associated with smaller cerebral tissue volume, but rather with smaller cerebrospinal fluid (CSF) and cranial volumes. These findings co-occurred with expected effects of alcoholism and aging on cerebral tissue and CSF volumes. The results point to early developmental divergences between groups with and without PTSD following adult trauma.  相似文献   
75.

Background and purpose:

Lipid rafts and caveolae are membrane microdomains with important roles in cell survival signalling involving the Akt pathway. Cholesterol is important for the structure and function of these microdomains. The ginsenoside Rh2 exhibits anti-tumour activity. Because Rh2 is structurally similar to cholesterol, we investigated the possibility that Rh2 exerted its anti-tumour effect by modulating rafts and caveolae.

Experimental approach:

A431 cells (human epidermoid carcinoma cell line) were treated with Rh2 and the effects on cell apoptosis, raft localization and Akt activation measured. We also examined the effects of over-expression of Akt and active-Akt on Rh2-induced cell death.

Key results:

Rh2 induced apoptosis concentration- and time-dependently. Rh2 reduced the levels of rafts and caveolae in the plasma membrane and increased their internalization. Furthermore, Akt activity was decreased and consequently, Akt-dependent phosphorylation of Bad, a pro-survival protein, was decreased whereas the pro-apoptotic proteins, Bim and Bax, were increased upon Rh2 treatment. Unlike microdomain internalization induce by cholesterol depletion, Rh2-mediated internalization of rafts and caveolae was not reversed by cholesterol addition. Also, cholesterol addition did not restore Akt activation or rescue cells from Rh2-induced cell death. Rh2-induced cell death was attenuated in MDA-MB-231 cells over-expressing either wild-type or dominant-active Akt.

Conclusions and implications:

Rh2 induced internalization of rafts and caveolae, leading to Akt inactivation, and ultimately apoptosis. Because elevated levels of membrane rafts and caveolae, and Akt activation have been correlated with cancer development, internalization of these microdomains by Rh2 could potentially be used as an anti-cancer therapy.  相似文献   
76.
77.
This paper argues that at the turn of the 19th century, nurses at the State Hospital in Morganton, North Carolina (now called Broughton Hospital) played critical roles in successfully implementing the best-known therapeutic methods of the time. They were also instrumental in developing the hospital's visibility and acceptance in rural western North Carolina. When the Hospital established its first nurse training school in 1895, this corps of first-generation western North Carolinians practising institutional nursing was highly esteemed in their field. Their skills not only served the community outside of the Hospital's walls, but were also sought out by other private and state asylums.  相似文献   
78.
Objectives:Congenital heart defects (CHD) are the most prevalent congenital anomalies. This study aims to examine the association between maternal occupational exposures to organic and mineral dust, solvents, pesticides, and metal dust and fumes and CHD in the offspring, assessing several subgroups of CHD.Methods:For this case–control study, we examined 1174 cases with CHD from EUROCAT Northern Netherlands and 5602 controls without congenital anomalies from the Lifelines cohort study. Information on maternal jobs held early in pregnancy was collected via self-administered questionnaires, and job titles were linked to occupational exposures using a job exposure matrix.Results:An association was found between organic dust exposure and coarctation of aorta [adjusted odds ratio (ORadj) 1.90, 95% confidence interval (CI) 1.01–3.59] and pulmonary (valve) stenosis in combination with ventricular septal defect (ORadj 2.68, 95% CI 1.07–6.73). Mineral dust exposure was associated with increased risk of coarctation of aorta (ORadj 2.94, 95% CI 1.21–7.13) and pulmonary valve stenosis (ORadj 1.99, 95% CI 1.10–3.62). Exposure to metal dust and fumes was infrequent but was associated with CHD in general (ORadj 2.40, 95% CI 1.09–5.30). Exposure to both mineral dust and metal dust and fumes was associated with septal defects (ORadj 3.23, 95% CI 1.14–9.11). Any maternal occupational exposure was associated with a lower risk of aortic stenosis (ORadj 0.32, 95% CI 0.11–0.94).Conclusions:Women should take preventive measures or avoid exposure to mineral and organic dust as well as metal dust and fumes early in pregnancy as this could possibly affect foetal heart development.  相似文献   
79.
Objectives. This report is an update on the outcomes in the management of pathologic Stage C (T3N0) prostate cancer (CaP) with postoperative irradiation.Methods. Between 1976 and 1994, 311 patients with pathologic Stage C CaP were treated with radical prostatectomy. Pathologic stage was as follows: C1, 60 patients (19%), C2, 146 patients (47%), and C3, 105 patients (34%). Gleason score was 2 to 4 in 10 patients (3.2%), 5 to 6 in 121 (39%), 7 in 101 (32%), and 8 to 10 in 76 (24%); median prostate-specific antigen (PSA) level was 11.9 ng/mL. Postoperative irradiation consisted of a median dose of 48 Gy. Follow-up was up to 18 years (median 5).Results. The 10-year actuarial survival was 81% and 10-year disease-free survival was 51%. Pathologic stage and Gleason score were independently predictive of recurrence, each with P >0.001 after controlling for the other. Patients with pathologic Stage C3 and Gleason score 7 to 10 were in the worst prognostic category and had 5.4 times the risk of recurrence compared with patients with pathologic Stage C1–C2, Gleason score 2 to 6. Preoperative PSA was a good (P = 0.02) predictor of disease-free survival. Clinical recurrence was seen in 28 patients (9%), including 10 (3.2%) with local recurrence. PSA recurrence (PSA greater than 0.05 ng/mL) developed in 68 patients (22%).Conclusions. With the known limitations of a nonrandomized clinical trial, on the basis of the experience of this study we recommend the use of moderate dose, limited-field postoperative radiotherapy in patients with pathologic Stage C disease with Gleason score greater than 4.  相似文献   
80.
Smartphone-based fluorescence imaging systems have the potential to provide convenient quantitative image guidance at the point of care. However, common approaches have required the addition of complex optical attachments, which reduce translation potential. In this study, a simple clip-on attachment appropriate for fluorescence imaging of protoporphyrin-IX (PpIX) in skin was designed using the built-in light source and ultrawide camera sensor of a smartphone. Software control for image acquisition and quantitative analysis was developed using the 10-bit video capability of the phone. Optical performance was characterized using PpIX in liquid tissue phantoms and endogenously produced PpIX in mice and human skin. The proposed system achieves a very compact form factor (<30 cm3) and can be readily fabricated using widely available low-cost materials. The limit of detection of PpIX in optical phantoms was <10 nM, with good signal linearity from 10 to 1000 nM (R2 >0.99). Both murine and human skin imaging verified that in vivo PpIX fluorescence was detected within 1 hour of applying aminolevulinic acid (ALA) gel. This ultracompact handheld system for quantification of PpIX in skin is well-suited for dermatology clinical workflows. Due to its simplicity and form factor, the proposed system can be readily adapted for use with other smartphone devices and fluorescence imaging applications. Hardware design and software for the system is made freely available on GitHub (https://github.com/optmed/CompactFluorescenceCam).  相似文献   
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