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91.
Human central and peripheral nerve cell tumors were examined in detail using antibodies to calcineurin, glial fibrillary acidic protein (GFAP) and neuron-specific enolase (NSE). Forty-eight formalin-fixed and paraffin-embedded specimens of human neuronal tumors, including 27 medulloblastomas, were examined. Calcineurin-positive cells were found in all peripheral nerve cell tumors and the two gangliogliomas, whereas 20 of the 27 medulloblastomas and one of the two cerebral neuroblastomas did not contain calcineurin-positive cells. Differentiation of cells along the neuronal lines was positively correlated with calcineurin immunoreactivity. NSE-positive cells were found in all of the tumors with the exception of the one cerebral neuroblastoma. NSE immunoreactivity was not invariably consistent with calcineurin immunoreactivity and non-neuronal cells were often positive. Calcineurin-positive cells were all devoid of GFAP, but NSE-positive cells expressed GFAP in some tumors. GFAP-immunoreactive cells were found only in central nerve cell tumors, and not in peripheral tumors. In addition, GFAP-positive cells in some tumors such as retinoblastoma and medulloblastoma morphologically revealed not only neoplastic but also reactive astrocytic features. 相似文献
92.
Relationship between tumor DNA ploidy and regional lymph node changes in lung cancer. 总被引:1,自引:0,他引:1
Seventy-four patients with lung cancer, resected consecutively from April 1989 to August 1990, were divided into (1) 21 with diploid tumors having a single G0/G1 peak and a coefficient of variation (CV) of 4.9 or less, (2) 18 with peridiploid tumors having a single G0/G1 peak and a CV at 5.0 or more, and (3) 35 with aneuploid tumors having multiple G0/G1 peaks. Aneuploid tumors had higher frequencies of lymphatic invasion and metastasis to the mediastinal lymph nodes. To evaluate the relationship between ploidy tumor status and immunologic competence of the regional lymph nodes, histologic findings and the proportion of killer T-lymphocytes were examined in the dissected lymph nodes. Aneuploid tumors had significantly lower proportions of paracortical hyperplasia and killer T-lymphocytes than did diploid and peridiploid ones in the nonmetastatic lymph nodes of N0 and N1 disease. These findings suggest the possibility that a decline in the antitumor competence of these lymph nodes could cause metastasis to the nodes. The recurrence rates were 19% in diploid, 33% in peridiploid, and 54% in aneuploid tumors, and the 2-year survival rates were 87%, 78%, and 44%, respectively. Peridiploid tumors showed intermediate values between diploid and aneuploid in terms of immunologic competence, recurrence rate, and survival. They were assumed to have a different proportion of aneuploid cells than the other two. 相似文献
93.
Unwoven cloth coated with 32 mg/g of a copolymer of N-benzyl-4-vinyl-pyridinium chloride and styrene was found to be effective in removing micro-organisms from water. In experiments demonstrating removal of Escherichia coli by filtration through ten sheets of the unwoven cloth, the rate of removal was 99.99% at a filtration rate of 2.6 cm/h, and remained at 99% even at a high filtration rate of 300 cm/h and a low influent concentration of the bacterial cells such as 10(3) cells/ml. The rate of removal tended to increase with a decrease in the influent bacterial concentration. Seven other bacteria and two yeasts were effectively removed by filtration through the unwoven cloth. Filtration through the unwoven cloth was also effective in removing spores of fungi from water but was not very effective in removing bacteriophage T4 from aqueous solution. 相似文献
94.
95.
T Inoue 《Shinrigaku kenkyu : The Japanese journal of psychology》1991,62(4):244-250
The structure of lexical representations in semantic memory and their processes were investigated through phonological priming effects in lexical decision task. The SOA condition between prime stimuli and target stimuli was varied in three experiments. In each experiment, subjects were 16 graduate or undergraduate students, and 24 three-letter-words (phonologically related/unrelated) or plus signs (neutral) were used as prime, followed by target composed of 12 three-letter-words and 12 three-letter-nonwords. The priming effects occurred in all the experiments, particularly when prime and target shared adjacent two letters. The effects at SOA 400 ms were not stable enough. At SOA 700 ms, only facilitation effects were obtained, but at SOA 1,000 ms, the effects of both facilitation and inhibition were obtained. These results suggested that in lexical representations phonologically similar words were closely related to each other in their structure, and that especially the phonological similarity between the sets of adjacent two letters was important regarding three-letter-words. The results also suggested that it might take longer time to spread activation in lexical representation than in conceptual representation. 相似文献
96.
Microsurgical and magnetic resonance imaging anatomy of the cerebello-medullary fissure and its application during fourth ventricle surgery. 总被引:3,自引:0,他引:3
The cerebellomedullary fissure, the only entrance or exit to the fourth ventricle, is surrounded rostrally by the cerebellar tonsils and the biventral lobules and caudally by the medulla oblongata, the tela choroidea, and the lateral recesses. This fissure is an important route in operations on the fourth ventricle. We studied the microsurgical and magnetic resonance imaging (MRI) anatomy of the fissure by using autopsied normal cerebellum. MRI revealed that the fissure is visible as a slit and is indicated by the enhanced choroid plexus and the flocculus. Oriented by the anatomical information thus obtained, we have surgically treated nine patients with a tumor either in or around the fourth ventricle. Preoperative MRI clearly demonstrated the tumors in relation to the cerebellomedullary fissure. It revealed the precise anatomical location and extension of the tumor, not only its inferior extension but also its lateral one. The MRI findings and microsurgical anatomy of the cerebellomedullary fissure were quite useful for the removal of the tumors in the fourth ventricle. 相似文献
97.
K Pak C J Kim H Inoue Y Wakabayashi J Watanabe Y Arai T Konishi T Tomoyoshi H Sako K Okino 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1990,81(10):1500-1505
To study the hemodialysis period following cadaveric renal transplantation, we reviewed 18 consecutive cadaver donor kidney pairs of which one kidney was transplanted at Shiga University of Medical Science (SUMS) while the contralateral kidney was transplanted at Kyoto Prefectural Medical University (KPMU) between January 1983 and September 1988. Of these 18 pairs, graft function was satisfactory and the recipient was free from hemodialysis in 13 pairs. However, the postoperative hemodialysis periods were different between the two centers. To clarify the factors causing this difference, recipient factors, such as age, HLA matching, total ischemic time of the graft (TIT), immunosuppression, onset of diuresis and postoperative complications were studied. There were no significant differences in age, HLA matching, or immunosuppression. TIT of cases at SUMS was significantly longer than that of cases at KPMU. The postoperative hemodialysis period at SUMS was 25.8 days and that at KPMU was 17.8 days, however, the difference was not statistically significant. The results of this study indicate that TIT seems to be a major factor relating to delayed graft function in cadaveric renal transplantation. 相似文献
98.
Y Iwai A Hakuba J Katsuyama Y Nagata S Nishimura K Abe T Asakura Y Inoue 《No shinkei geka. Neurological surgery》1990,18(1):71-75
Ectopic pituitary adenomas are very rare and only 17 cases have been reported. In this paper we present a case of large pituitary adenoma originating in the suprasellar region. A 26-year-old man was admitted to our clinic with a chief complaint of headaches. Neurological examination revealed slight disorientation and bilateral choked disk. Hormonal study revealed that the serum prolactin level was 3300ng/ml and serum growth hormone level was 29.5ng/ml. Computed tomography showed a large mass in the suprasellar region extending upward to the third ventricle and backward to the pons. T1-weighted MR imaging revealed that the intensity of the mass was the same as that of the cerebral cortex and the pituitary gland was showing high intensity in the pituitary fossa. The tumor was radically removed via the transpetrosal transtentorial approach. Histologically, the tumor was a prolactin-growth hormones producing pituitary adenoma. The literature was reviewed and the origin of the tumor was discussed. 相似文献
99.
Ryo Aeba Toshiyuki Katogi Kenichi Hashizume Yoshimi Iino Kiyoshi Koizumi Kentaro Hotoda Shinya Inoue Hideki Matayoshi Akihiro Yoshitake Ryohei Yozu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2003,51(7):302-307
OBJECTIVE: Severe aortic arch obstruction including an interrupted aortic arch in congenital complex heart anomalies remains a challenge in surgical management. METHODS: Treatment and outcomes in 75 consecutive patients who underwent an aortic arch repair as the first step of the staged repair protocol between 1975 and 2000 were reviewed. Their ages at repair ranged from 1 day to 8.5 months. RESULTS: Cross-sectional postoperative follow-up data were available in all the patients. The follow-up period ranged from 0 to 27.6 years (mean: 7.3 +/- 7.3 years). There were 20 postoperative hospital deaths (27%) and 7 late deaths. The Kaplan-Meier estimate of survival was 81.3% +/- 4.5% at 1 month, 68.0% +/- 5.4% at 1 year, 65.0% +/- 5.5% at 5 years, 63.1% +/- 5.7% at 10 years, 63.1% +/- 5.7% at 20 years. By Cox regression analysis, body weight of 2.5 kg or less is the only independent determinant of postoperative mortality (p = 0.04, multivariable odds ratio: 2.50, [95% confidence interval: 1.02-6.1]). The aortic arch morphology, the primary cardiac lesion, or date of operation did not reach a statistically significant level to show correlation with mortality. Reintervention to reconstruct the aortic arch was performed at 9 occasions in 8 of the 55 patients who survived the primary operation (14.5%). The Kaplan-Meier estimate of the reintervention-free rate was 91.3% +/- 4.2% at 5 years, 85.5% +/- 5.6% at 10 years, 75.6% +/- 8.2% at 20 years. Using multivariable Cox regression analysis, interrupted aortic arch (versus aortic coarctation) was the only independent predictor of a shorter time to reintervention (p = 0.001, multivariable odds ratio: 16.1, [95% confidence interval: 3.2-80.2]). CONCLUSIONS: The staged repair protocol was associated with significant limitations in patient survival and with the development of recurrent aortic arch obstruction. Thus, a primary repair protocol may serve as an alternate approach, especially in patients with low weight or with an interrupted aortic arch. 相似文献
100.
The effects of neurokinin A (NKA) on freshly isolated smooth muscle cells from the rat vas deferens were investigated electrophysiologically. NKA (10(-7) M) prolonged the duration of action potentials without affecting resting potentials. Under voltage-clamp conditions, NKA (10(-7) M) suppressed an outward K+ current activated by depolarizing voltage steps. Substance P (SP, 10(-7) M) did not affect the K+ current, suggesting that NKA is more potent in suppressing the K+ current than SP is, as is also true for the contractions of smooth muscles of the rat vas deferens. The suppression of the K+ conductance now reported may contribute to NKA-induced smooth muscle contraction. 相似文献