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31.
Harrath R Douche-Aourik F Bourlet T Ismail A Omar S Aouni M Pozzetto B 《Annales de biologie clinique》2004,62(1):33-39
Many mouse models of human enterovirus disease have been pro- posed, concerning both acute and persistent infection. However, rather paradoxically since the usual way of contamination is fecal-oral, most of them used a systemic route of infection. The aim of the present work was to follow the development of an experimental enterovirus infection and to study the viral persistence at the organ level. Twenty-eight female 3-week old BALB/c mice were infected with 5 x 10(4) TCID(50) of coxsackievirus B3 (CV-B3), Nancy strain, by oral route using a rigid cannula introduced into the stomach. The kinetics of infection was studied by sacrificing 2 animals at different times post infection (from 1 hour to 90 days). The presence of the virus in various organs (small intestine, heart, pancreas, lung, spleen, kidney, liver) was studied by cell culture and RT-PCR. As soon as one hour post infection, the virus was detected in the small intestine. In the heart, the virus was present at 24 and 48 hours post infection by RT-PCR and culture, respectively. At 5 days post infection, all the organs but the liver were found infected. The virus was detected up to 15 days in kidney, 21 days in pancreas, 30 days in lung and spleen, and 45 days in intestine, by both culture and PCR. The heart was still found infected 90 days post infection by both techniques. These results show the dramatic cardiotropism of CV-B3 inoculated by oral route, with a detection of the virus very soon in the course of infection (24 hours) and a persistence of the virus for more than 3 months. The intestine, the initial target of enterovirus infection, can also be considered as a site of viral persistence. 相似文献
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33.
Nawawi HM Yazid TN Ismail NM Mohamad AR Nirwana SI Khalid BA 《The Malaysian journal of pathology》2001,23(2):79-88
The objectives of this study were to: (i) evaluate the diagnostic sensitivity and specificity of the biochemical bone markers: serum total alkaline phosphatase (TALP), bone specific alkaline phosphatase (BSALP) and urinary deoxypyridinoline (Dpyr) in postmenopausal osteoporosis, (ii) compare the bone turnover of postmenopausal osteoporotic patients without and with hormone replacement therapy (HRT) against controls and (iii) identify the correlation between these bone markers and bone mineral density (BMD). We examined 42 postmenopausal women with BMD proven osteoporosis and 35 control subjects. Serum TALP, BSALP and urinary Dpyr were measured. All three biochemical bone markers showed comparable moderate diagnostic sensitivity but Dpyr had the highest diagnostic specificity. There were significantly higher serum TALP, BSALP and urinary Dpyr levels in non-HRT treated patients compared to controls (p<0.005, <0.0001 and <0.005 respectively). There were no significant differences in the levels of all three bone markers between HRT treated patients and control subjects. There was no significant correlation between TALP, BSALP or Dpyr and BMD in both controls and patients. In conclusion, the biochemical bone markers are not useful in diagnosis of postmenopausal osteoporosis but may have a role in monitoring progress and response to treatment. HRT treatment reduces bone turnover of postmenopausal osteoporosis. 相似文献
34.
Marc Fischer Gabriele Wiest Ismail Tekesin Kerstin Amann Johannes Mann Christian Hasslacher Harald Derks Gerhard Mall 《Virchows Archiv : an international journal of pathology》1992,420(6):499-506
Summary The effects of combined renovascular hypertension and diabetes mellitus on the rat heart were investigated in order to detect possible synergistic effects of the two conditions. Hypertensive diabetic and hypertensive non-diabetic animals were compared to diabetic and non-diabetic controls. Hypertension was established for 12 weeks by a surgical stenosis of the left renal artery; diabetes mellitus was maintained for 8 weeks by a single intraperitoneal injection of 60 mg/kg streptozotocin. Light microscopic stereology did not reveal significant divergences between diabetic hypertensives and non-diabetic hypertensives. Hypertension induced a focal perivascular and interstitial fibrosis with increased volume densities of non-vascular interstitium and fibrosis (P<0.001). Capillary density (QA) was decreased in transverse sections (P<0.01) and increased in longitudinal sections (P<0.01). This indicates a three-dimensional remodelling of the capillary bed with an increased number of obliquely running capillaries. At least the length density (LV) of capillaries (mm/mm3) tends to be normalized in long-term renovascular hypertension. At the ultrastructural level, a synergism of hypertension and diabetes mellitus was observed: the volume ratio of mitochondria to myofibrils was significantly decreased in hypertensive diabetics, but not in non-diabetic hypertensives or in diabetics. This may enhance the risk of cardiac deterioration. We conclude that the primary target of the synergistic damage in hypertensive diabetic heart muscle disease is the myocardial cell and not the cardiac interstitium.Preliminary results of this study have been published in: Mall G (1991) Morphometric study on the rat heart in combined renovascular hypertension and diabetes mellitus. In: Nagano N, Dhalla NS (eds) The diabetic heart. Raven Press, New York, pp 115–124Dedicated to Prof. Dr. med. G. Seifert on the occasion of his 70th birthday 相似文献
35.
36.
T. Gaafar S. Ismail M. Helmy A. Afifi N. Guirguis R. El Ridi 《Parasitology research》1993,79(2):103-108
Schistosoma haematobium soluble egg antigens (SH SEAs) induce intense granulomas in human hosts that often culminate in severe disease. In an attempt to identify the SH SEA fractions that are responsible for pathology, we combined T-cell Western blotting and an in vitro model of granuloma formation. Whole SH SEAs were dotted onto nitrocellulose pieces or were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and electrotransferred onto nitrocellulose paper. Horizontal strips bearing the separated antigens were solubilized in dimethylsulfoxide and precipitated in carbonate/bicarbonate buffer. Antigen-free and antigen-bearing particles were used to stimulate peripheral blood mononuclear cells (PBMCs) obtained fromS. haematobium-infected patients and sex- and agematched healthy controls to form granulomas in vitro. Whole SH SEA-bearing nitrocellulose particles elicited in vitro formation of granulomas by PBMCs from infected donors. The response was similar in sensitivity, specificity, and reproducibility to that evoked by SH SEA-bound polyacrylamide beads. The results obtained in samples from 30 patients and 10 controls tested with SH SEA-separated fractions revealed that SEA bands of 84 000, 63 000, 57 000, 55 000, 40 000, 30 000, and 28 000 Da elicited in vitro granuloma reactions by PBMCs of almost all infected patients. Conversely, separated soluble adult-worm antigens failed to stimulate PBMCs of infected patients to form granulomas. This study is the first to identify the SH SEA fractions that evok in vitro granuloma formation and represents an initial step toward the development of an anti-urinary schistosomiasis pathology vaccine. 相似文献
37.
After 20-day-old rats are placed on a vitamin-A-deficient diet (VAD) for a period of 10 weeks, the seminiferous tubules are found to contain only Sertoli cells and a small number of spermatogonia and spermatocytes. Retinol administration of VAD rats reinitiates spermatogenesis, but a stage-synchronization of the seminiferous epithelium throughout the testis of these rats is observed. In order to determine which cell type is responsible for this synchronization, the germ cell population has been analyzed in whole mounts of seminiferous tubules dissected from the testes of rats submitted to the following treatments. Twenty-day-old rats received a VAD diet for 10 weeks and then were divided into three groups of six rats. In group 1, all animals were sacrificed immediately; in group 2, the rats were injected once with retinol and sacrificed 3 hr later; in group 3, the rats were injected once with retinol, placed on a retinol-containing diet for 7 days and 3 hr, and then sacrificed. Three rats from each group had one testis injected with 3H-thymidine 3 hr (groups 1 and 2) or 7 days and 3 hr (group 3) before sacrifice. Three normal adult rats (approximately 100 days old) served as controls. Labeled and unlabeled germinal cells were mapped and scored in isolated seminiferous tubules. In group 1, type A1 and type A0 spermatogonia as well as some preleptotene spermatocytes were present; type A2 A3 A4 In, and B spermatogonia were completely eliminated from the testis. Neither type A1 mitotic figures nor 3H-thymidine-labeled-type A1 nuclei were seen. Three hr after retinol injection (group 2), type A1 mitoses, but no labeled type A1 nuclei were observed. At 7 days and 3 hr after retinol administration (group 3), type A4 and In Spermatogonia as well as type A1 spermatogonia were present. A few residual pachytene spermatocytes were found, and some type A0 cells were labeled. These results indicate that VAD caused, in addition to an impairment of spermatogenesis at the preleptotene spermatocyte step, a selective momentary arrest of surviving type A1 spermatogonia at the G2 phase of their cell cycle. Following administration of vitamin A to VAD rats, these type A1 cells reinitiated spermatogenesis synchronously and, after several cycless of proliferation and renewai, reconstituted the seminiferous epithelium in a stage-synchronized manner. 相似文献
38.
SM Ismail 《Journal of clinical pathology》1993,46(11):1067-1068
39.
40.
Effects of alpha-adrenoceptor agonists and antagonists on insulin secretion, calcium uptake, and rubidium efflux in mouse pancreatic islets 总被引:4,自引:0,他引:4
N A Ismail E S El-Denshary L A Idahl P Lindstr?m J Sehlin I B T?ljedal 《Acta physiologica Scandinavica》1983,118(2):167-174
Epinephrine, norepinephrine or the more selective alpha-2 adrenoceptor agonist, clonidine, inhibited insulin release from isolated pancreatic islets of lean mice or obese mice homozygous for the gene ob. Clonidine was highly effective at 0.1 mumol/l. In contrast, the preferential alpha-1 adrenoceptor agonist, phenylephrine, had no or only a modest effect at 10 mumol/l. The effects of norepinephrine or clonidine were counteracted by yohimbine, a preferential blocker of alpha-2 receptors, but not by prazosine, an alpha-1 receptor blocker. The glucose-stimulated uptake of 45Ca2+ in the islets was only consistently inhibited by epinephrine. This effect was counteracted by yohimbine. Clonidine had no effect on the release of 86Rb+ from preloaded islets. It is concluded that insulin secretion is suppressed by alpha-2 receptor agonism in the pancreatic beta-cells and that this effect is mediated by mechanisms other than the transmembrane fluxes of calcium or potassium ions. 相似文献