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991.
We report a case of torsion of an accessory lobe of the liver (ALL) in a 14-year-old girl. The patient was admitted for acute abdominal pain and laparotomy revealed an ALL, the pedicle of which was elongated with 180° torsion. The diagnosis was not made preoperatively because of the rarity of this condition. However, a close relationship between omphalocele repair and the development of ALL has been reported; thus, a history of omphalocele repair should alert the doctor to the possibility of this condition, which could be suggested by imaging findings preoperatively. Torsion of an ALL should be included in the differential diagnosis of a patient with a history of omphalocele, who presents with acute abdominal symptoms.  相似文献   
992.
A-76-year-old woman consulted for open biopsy for a pulmonary mass. Thoracoscopic wedge resection was performed. The lesion was histologically diagnosed as nonspecific inflammation. On the first postoperative day (POD1), the patient lost consciousness transiently. Eleven hours after the first stroke, the patient experienced a second stroke together with hypoxia. Pulmonary perfusion scan on POD2 showed multiple perfusion defects, and the patient was diagnosed with pulmonary embolism (PE). Thrombolitic therapy was started. Neurological symptoms didn’t improve, and cerebral angiography on POD3 showed delayed perfusion in superficial veins. The patient was diagnosed with cerebral venous thrombosis (CVT). Thrombolytic and anticoagulant therapy had been continued, and the patient was found to have hemorrhagic cerebral infarction on POD11. After persistent therapy, the patient was discharged on POD120. Although both PE and CVT are rare complications after thoracic surgery, we must consider these complications in patients undergoing thoracic operations including thoracoscopic surgery.  相似文献   
993.
Purpose  We have been developing a computer-aided detection (CAD) system for lung nodules on multidetector row computed tomography (MDCT). The scheme for nodule detection in this system is featured by three-dimensional analysis for nodule detection in nodules and their surroundings, which is designed to discriminate nodules from blood vessels. The purpose of this study was to evaluate the CAD system. Materials and methods  MDCT images from 30 patients with lung nodules were read twice, 3 weeks apart by a chest radiologist to detect noncalcified nodules of ≥4 mm. The first reading was without CAD, and the second reading was with CAD. Based on the reference standard later determined by another chest radiologist, the sensitivity of the former chest radiologist without or with CAD was obtained; the sensitivity and false-positive rate of the system alone were also obtained. Results  The reference standard consisted of 66 nodules. The sensitivity of the chest radiologist was 77% (51/66) without CAD and 91% (60/66) with CAD, showing a significant improvement. The CAD system alone showed a sensitivity of 79% (52/66) with the false-positive rate of 4.5 per patient. Conclusion  Although preliminary, these results indicate the efficacy of the CAD system.  相似文献   
994.
Background: We have investigated how recirculating lymphocytes patrol the liver in a normal steady state. Methods: Thoracic duct lymphocytes of congeneic rats were intravenously transferred to host rats and donor cell trafficking in the liver and hepatic lymph was examined. Host hepatic lymph nodes (HLNs) were selectively removed, which allowed liver‐derived donor cells to collect in the thoracic duct without transit in the intervening HLNs. Results: The number of donor cells in the thoracic duct lymph significantly increased over the baseline 3, 5 and 11 h after transfer in the HLN‐removed, non‐pretreated, and HLN‐ligated (in which a lymph efflux was blocked) groups, respectively. Histologically, donor cells appeared in the portal area from 0.5 h after transfer and frequently attached to the basal lamina of portal vein both externally and internally. Three hours after transfer, a few donor cells appeared in the subcapsular sinus of HLNs. Conclusion: The minimal transit time of rat recirculating lymphocytes is 3–4 h in the liver and 5–8 h in the hepatic LNs, in a normal steady state. Recirculating lymphocytes might transmigrate through the portal vein as well as the sinusoid in the periportal zone. This rapid transit might enable an efficient surveillance of the liver portal area by the recirculating lymphocytes.  相似文献   
995.
We report a case of endocrine carcinoma of the sigmoid colon. A 71-year-old man was admitted to our hospital because of constipation and bloody stool. Colonoscopy showed a mass lesion with irregular ulceration in the sigmoid colon. He was given a diagnosis of the poorly differentiated adenocarcinoma of the colon, and underwent sigmoidectomy with dissection of the lymph nodes. Histological and immunohistochemical examinations of the resected specimen revealed endocrine carcinoma. Endocrine carcinoma of the colon is rare, and the prognosis is very poor. We discuss this case with references.  相似文献   
996.
BACKGROUND: Although mutations in the interferon (IFN) sensitivity determining region (ISDR) of hepatitis C virus (HCV) have been reported to be useful as a predictive viral factor for IFN therapy in patients infected with HCV-1b, such laboratory research has not been favorably translated into the clinic. To promote such translation, we attempted the establishment of a rapid and simple polymerase chain reaction (PCR) combined with melting curve analysis (MCA) to screen for mutations in the ISDR and for the monitoring of HCV quasispecies. METHODS: A PCR-MCA protocol was established using in-house primers and hybridization probes designed according to the results of direct sequencing of 34 HCV-1b samples. Then, the performance of PCR-MCA was verified by comparing with mutation profiles obtained by direct sequencing and sequencing after cloning. RESULTS: The MCA assay revealed that melting temperature (Tm) was inversely correlated with the number of nucleotide (nt) and amino acid substitutions in the ISDR deduced on the basis of the results of direct sequencing. A boundary Tm of 58.0 degrees C allowed us to discriminate HCV genomes into two groups: one with a Tm >58.0 degrees C had no or a low number of nt substitutions, while the other genomes with a Tm <58.0 degrees C had a high number of nt substitutions, corresponding to wild-type in the former and mutant-type in the latter in respect of a clinical setting for IFN therapy. Moreover, this MCA assay provided precise discrimination of Tm between clones, reflecting the degree of the genetic complexity of HCV genomes. CONCLUSIONS: This study indicates that the MCA assay is useful to rapidly and simply screen the mutational status of the ISDR of HCV, as well as in using the ISDR as one of the targets for discriminating the genetic complexity of HCV genomes. The MCA assay could also be applicable as a convenient and useful screen of the genetic heterogeneity of clones relating to HCV quasispecies.  相似文献   
997.
Abstract: Fullerene‐C60 (C60) is mainly applied in the aqueous phase by wrapping with water‐soluble polymer or by water‐solublizing chemical‐modification, whereas C60 dissolved in oil is scarcely applied; still less explicable is its toxicity. We dissolved C60 in squalane at near‐saturated or higher concentrations (220–500 ppm), named LipoFullerene (LF‐SQ), and examined its biological safety. LF‐SQ was administered at doses of 0.49–1000 µg/ml to fibroblast cells Balb/3T3, and showed that cell viability was almost equal to that of the control regardless of the UVA‐ or sham‐irradiation, indicating no phototoxicity. Reverse mutation by LF‐SQ was examined on four histidine‐demanding strains of Salmonella typhimurium and a tryptophan‐demanding strain of Escherichia coli. As for the dosages of LF‐SQ (313–5000 µg/plate), the dose‐dependency of the number of reverse mutation colonies of each strain did not show a marked difference when compared with the negative control, regardless of the metabolic activation, in contrast to twice or more differences for five positive controls (sodium azide, N‐ethyl‐N′‐nitro‐N‐nitrosoguanidine, 2‐nitrofluorene, 9‐aminoacridine, and 2‐aminoanthracene). In human skin biopsy built in a diffusion chamber, C60 permeated into the epidermis at 33.6 nmol/g tissue (24.2 ppm), on administration with LF‐SQ containing 223 ppm of C60, but not detected in the dermis even after 24 hrs, as analysed by HPLC. It is presumed that LF‐SQ can permeate into the epidermis via the corneum but can not penetrate the basement membrane, and so can not reach into the dermis, suggesting no necessity for considering a toxicity of C60 due to systemic circulation via dermal veins. Thus, C60 dissolved in squalane may not give any significant biological toxic effects such as photocytotoxicity, bacterial reverse mutagenicity, and permeability into the human skin.  相似文献   
998.
Nitrate biosynthesis is a known mammalian process, and macrophages from mice treated with Escherichia coli lipopolysaccharide (LPS) have been shown to be capable of nitrate synthesis. Cell culture studies showed that macrophages produce nitrite as well as nitrate. We report here N-nitrosamine formation by stimulated macrophages. Experiments were carried out with the macrophage cell lines, J774.1, WEHI-3 and RAW 264. Macrophages were cultured in Dulbecco's modified Eagle's medium (pH 7.5) supplemented with calf serum (10%). The concentration of nitrate in the supernatant was measured. N-nitrosamines were extracted with dichloromethane and the extracts were analysed by gas chromatography-thermal energy analysis. When J774.1 (1.5 X 10(6) cells/ml) were incubated with LPS (10 micrograms/ml) and morpholine (15 mM) for 72 h at 37 degrees C, N-nitrosomorpholine (NMOR) was produced (0.8 microM). The amount of nitrite produced was 50 microM. RAW 264 and WEHI-3 also produced NMOR; LPS was required for nitrite and NMOR formation. gamma-Interferon (IFN) promoted both NMOR (2.5 microM) and nitrite (70 microM) formation. Nitrite (150 microM) incubated with morpholine and the medium did not form NMOR. Kinetics of LPS-induced nitrite and NMOR formation in J774.1 showed that the rate of NMOR formation was highest in the middle incubation period (24-36 h), although the nitrite concentration was highest in the latter incubation period (48-60 h). Our results showed that macrophages may be capable of nitrosamine formation under physiological conditions that do not normally permit this reaction.  相似文献   
999.
Abstract: Specific types of early gastric cancer were investigated in accordance with the cancer surface area and the degree of penetration by means of quantitative measurements of the surface area of early gastric cancer using the interactive image analysis system. The results indicated a significant correlation between the surface area and the penetration depth in ordinary early gastric cancer. However these correlations were not observed in both well and poorly differentiated adenocarcinoma cases of the so-called PEN and SUPER types, which showed a significant specificity when compared with ordinary early gastric cancer. The PEN and SUPER types of early gastric cancer also exhibited various clinicopathological characteristics, and it was suggested that the poorly differentiated PEN type might be the initial lesion of a linitis plastica type gastric cancer. Examination of the conditions of the mucosa surrounding the cancer revealed a difference between the PEN and the SUPER types, and this suggested that the environment at the site of a cancer growth influences the type of growth and the spread of early gastric cancer.  相似文献   
1000.
A-49-year-old man was admitted because of a lower abdominal mass. During the five days prior to admission, he had noted fever and lower abdominal pain. Palpation of the abdomen revealed a tender mass, 10 cm in diameter, in the suprapubic region. An x-ray revealed an irregular collection of gas, 9 cm in diameter, in the pelvic cavity, which appeared as a mirror image when the patient was upright. Based on the physical finding and the results of a barium enema, abdominal CT, MRI, and small intestine imaging, a diagnosis of leiomyosarcoma of the ileum was made. Excision of the tumor and part of the small intestine was performed. A saccular tumor, 11 x 6 x 5 cm, was found 1.0 m from the cecum and growing out of the wall of the ileum. A large amount of pus was found inside the cavity. The pathological diagnosis was leiomyosarcoma.  相似文献   
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