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1.
We studied choline acetyltransferase (CAT) activity in a rat model of brachial plexus injury. In experiment 1, we found that the CAT activity was remarkably high in the anterior roots and low in the posterior roots. In experiment 2, nerve root segments were extracted and examined for CAT activity in the root avulsion group (group A) and the plexus severance group (group B). CAT activity decreased day by day in group A, reaching about 1/20 of the normal 5 days postoperatively. By contrast, in group B activity decreased only slightly, and even at 90 days postoperatively was about 6,000 cpm (one-half normal level). As a result, CAT activity enabled us to distinghish postganglionic from preganglionic injury of the cervical roots. Furthermore, it was a useful adjunct for minimizing nerve loss in intercostal nerve transfer, distinguishing motor and sensory branches of the intercostal nerve, and evaluating the motor nerve activity. © 1995 Wiley-Liss, Inc. 相似文献
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Yasutake Saekt Kouichi Shiozawa Cheol -Ho Paik Keiji Yanagisawa 《Journal of muscle research and cell motility》1991,12(2):152-160
Summary To clarify the activation-dependence of dynamic mechanical characteristics of contracting cardiac muscle, we analysed the healthy central segment length (SL) response to step decrease in tension at two different levels of barium contracture (0.2 mM and 0.5 mM Ba2+) in rat papillary muscles with a fixed initial SL. The time course of this response is thought to reflect the kinetics of actin-myosin interaction. The muscle was released stepwise from the steady contracture tension (Tc) to new steady tension levels (Tr) of varying magnitudes at 22° C. The SL responses consisted of four phases at Tr/Tc > 0.3. The amplitude of shortening in the second phase, after the initial rapid and minute shortening in the first phase, increased with an increase in amplitude of step tension reduction, and was greater at the higher activation level when compared at an identical amount of Tr/Tc. The fourth phase, after the remarkable lengthening in the third phase, was an extremely slow and minute shortening toward a new steady SL under the new tension. The duration of the second and third phase was quite insensitive to activation level at Tr/Tc > 0.85, but became longer at the higher activation level with larger amounts of tension reduction. The velocity measured from the initial quasi-steady SL shortening in the second phase increased significantly with the increase in activation level. These results are discussed in terms of cross-bridge kinetics underlying the isotonic SL transients at two different activation levels. 相似文献
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Kouichi Kanagawa Hiroshi Ishikura Alcihiro Ishitu Chisa Kimura Toshimori Seki Tomohiko Kayanagi Takashi Yoshiki 《Pathology international》1995,45(3):196-201
Rat kidneys were perfused with anti-intercellular adhesion molecule-1 (anti-ICAM-1) monoclonal antibody prior to allo-transplantation. In the two strain combinations examined, LEJ-to-WKAH transplants resulted in accelerated graft loss, and no prolongation of graft survival. The accelerated graft logs was the resut of frequent occurrence of necrotizing arterttis wlthln the grafts. In contrast, TO-to-WKAH transplants resulted in no change In graft survival and no arteritis. Necratidng vasculitis in the LEJ-to-WKAH grafts was characterlzed by flbrinoid necrosis, collection of cellular infiltrates and serum macromolecular protein entrapment. The F(ab')2 form of anti-ICAM-1 antlbody partially preserved the antibody's capacity to accelerate graft loss. Therefore, although endothelial injury by Fc-mediated cytotoxicity may be involved in vascular damage, other mechanisms also come into play. The amount and distribution pattern of ICAM-1 antigen were identical in both TO and LEJ strains. Intravenous anti-CAM-1 antibody administration combined with lipopolysaccharide, Poly(1)-Poly(C), warm ischemia to the kidney, or subcutaneous immunization with allogeneic spleen cells, but without renal transplantation, did not generate necrotizing vasculitis or proteinuria. These observations plus our previous data on the rat liver transplantation model clearly show that graft perfusion with anti-ICAM-1 monoclonal antibody invokes extensive vascular damage within allografts by Fc-mediated and Fc-independent mechanisms, depending on the donor-to-host combination. 相似文献
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The proliferative responses of Peyer's patch (PP) T cells from aged BALB/c mice to concanavalin A (Con A) are considerably reduced, as compared to those of the young (P < 0.001). This reduced reactivity of aged T cells could be partly, but not entirely, corrected by interleukin 2 (IL-2) (P < 0.001). PP T cells from aged mice responded synergistically to a protein kinase C (PKC) activator, phorbol myristate acetate (PHA), plus a calcium ionophore, ionomycin, at much lower concentrations than to Con A (P < 0.001); however, the maximal proliferative response still remained nearly at 8/10th of the young (P < 0.01) and higher levels of PMA (but not of ionomycin) were required (P < 0.001). Addition of IL-2 restored the diminished response to the levels of the young T cells (P < 0.05), but that of Con A did not (P > 0.05). The proliferative responses of PP B cells to lipopolysaccharide (LPS) do not differ from those of the young (P > 0.05), but the spontaneous proliferation of aged (unstimulated) B cells is enhanced nearly twofold versus that of the young (P < 0.001). Like the PP T cells, PP B cells from aged mice also responded synergistically to PMA plus ionomycin but to a lesser degree than those of the young under the same stimulation (P < 0.01). Their maximal proliferation required higher levels of PMA, but not of ionomycin and was also diminished (P < 0.01), compared to that of the young. B cell stimulatory co-factors, IL-4 and IL-6, failed to affect the response of aged and young B cells to PMA plus ionomycin (P > 0.05), whereas LPS remediates the reduced response of aged B cells to PMA plus ionomycin. Thus, T and B cells from senescent PP demonstrate an impaired proliferative responsiveness via the Ca-dependent PKC pathway. A T cell mitogen and B cell stimulatory cytokines did not alter this activation pathway, once optimally stimulated. Whereas, T cell stimulatory cytokine IL-2 and B cell mitogen LPS could restore the age-associated decline of the corresponding lymphocyte subsets, T and B cells, in activation of the Ca-dependent pathway. The altered transmembrane signal transduction appears to be intrinsically defective in these aged PP T and B cells. 相似文献
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Hyperthermo-chemotherapy combined with cytoreductive surgery for the treatment of gastric cancer with peritoneal dissemination 总被引:6,自引:0,他引:6
Yutaka Yonemura M.D. Takashi Fujimura M.D. Sachio Fushida M.D. Shigeru Takegawa M.D. Toru Kamata M.D. Kanji Katayama M.D. Takeo Kosaka M.D. Akio Yamaguchi M.D. Kouichi Miwa M.D. Ituo Miyazaki M.D. 《World journal of surgery》1991,15(4):530-535
Continuous hyperthermic peritoneal perfusion (CHPP) with anticancer agents (mitomycin C and cisplatin) in warm saline was performed in patients with peritoneal dissemination of gastric cancer following resection of the primary lesion. The effect of CHPP was examined by a second-look operation. This study includes 41 cases of gastric cancer with peritoneal dissemination but without liver metastasis treated during the past 6 years. The overall median survival was 14.6 months to 64.2 months from CHPP to death and the 3-year survival rate was 28.5%. Second look surgery revealed a remarkable diminution in the degree of peritoneal dissemination in 7 (50%) of 14 patients with disappearance of ascites after only one course of CHPP in 7 (77.8%) of 9 patients. Long-term 3 year-survival was noted in 4 (9.8%) patients on CHPP. Side effects were renal insufficiency in 2 (5%) patients, leukopenia in 2 (5%) patients, and perforation of the small intestine in 1 (2%) patient. These results suggest the effectiveness of CHPP in the treatment of gastric cancer with peritoneal dissemination.
Resumen La perfusión hipertérmica continua (PHTC) con agentes anticancerosos (mitocina G y cisplatino) y solutión salina fue realizada en pacientes con cáncer gástrico con diseminación peritoneal después de resección de la lesión primaria, y el efecto de PHTC fue determinado mediante reexploración (operación de second look, OSL). La población de pacientes está constituída por 41 casos de cáncer gástrico con diseminación peritoneal pero sin metástasis hepáticas, tratdos en el curso de los últimos 6 años. La sobrevida media global fue de 437 dias (rango 28 a 1925 días) desde la PHTC hasta la muerte y la tasa de sobrevida a 3 años fue 28.5%. La OSL reveló una notoria disminución de la diseminación peritoneal en 7 (50%) de 14 casos y desaparición de la ascites después de sólo un ciclo de PHTC en 7 de 9 casos con ascitis. Sobrevida de 3 años ocurrió en 4 casos. Los efectos colaterales fueron insuficiencia renal en 2 casos (5%), leucopenia en 2 casos (5%) y perforación del intestino delgado en 1 caso (2%). Los anteriores resultados sugieren que la PHTC es eficaz en el tratamiento del cáncer gástrico con diseminación peritoneal.
Résumé La perfusion péritonéale continue hyperthermique (PPCH) avec des agents anticancéreux comme le mitomycine C et la cis-platine avec sérum physiologique chauffé a été instaurée lorsqu'une carcinose d'origine gastrique a été trouvée. Les effets de la PCH ont été évalués chez 16 patients lors d'un second-look (SL). Cette étude concerne 41 patients avec carcinose péritonéale sans métastase hépatique observés au cours des 6 dernières années. La survie globale médiane était de 437 jours (extrêmes 28 à 1925 jours): le taux de survie a 3 ans était de 28.5%. Les lésions avaient diminué de façon notable chez 7 (50%) de 14 patients. L'ascite a disparu dans 7 des 9 cas. Une survie à long terme (3 ans) a été notée dans 4 cas. Les effets secondaires ont été une insuffisance rénale dans 2 cas (5%), une leucopénie dans 2 cas (5%) et une perforation de l'intestin grêle dans un cas (2%). Les résultats suggèrent que la PPCH est efficace dans le traitement du cancer gastrique avec dissémination péritonéale.相似文献
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Yahata N Kawanishi Y Okabe S Kimura Y Okada T Otani M Shimizu T Nakao T Ohyashiki K 《American journal of nephrology》2000,20(5):402-407
A 66-year-old woman was admitted to our hospital for evaluation of edema of the extremities. Laboratory findings suggested that she had nephrotic syndrome and chronic lymphocytic leukemia (CLL). Renal biopsy (with PAM staining) showed a spike formation in the capillary wall. Immunofluorescent staining revealed deposition of immunoglobulin G (IgG) and the third component of complement in the glomerular basement membrane. Electron microscopy showed fibrillary deposits in the subepithelium. These findings indicated membranous glomerulonephritis (MGN). In addition, focal segmental sclerosis and interstitial lymphocytic infiltration were observed in the renal biopsy specimen. In CLL patients nephrotic syndrome occurs rarely. Even if the complication occurs, MGN is not frequent. Both diseases are suspected to occur in association with each other, and immunologic abnormality contributes to their coexistence. Although administration of prednisolone and endoxan improved leukocytosis, proteinuria was not sufficiently improved with combination therapy. 相似文献
10.
Kawanishi M; Kohno T; Otsuka T; Adachi J; Sone S; Noguchi M; Hirohashi S; Yokota J 《Carcinogenesis》1997,18(11):2057-2062
Allelotype and replication error (RER) phenotype analyses were performed to
clarify the pathogenetic significance of inactivation of tumor suppressor
genes and genomic instability in the genesis and progression of small cell
lung carcinoma (SCLC). We examined 37 cases of SCLC for loss of
heterozygosity (LOH) and microsatellite instability at 49 loci on all 39
nonacrocentric chromosomal arms. LOH was frequently (>70%) detected on
chromosomes 3p (29/32, 90.6%), 5q (15/21, 71.4%), 13q (25/26, 96.2%), 17p
(22/25, 88.0%), and 22q (24/33, 72.7%). Frequent LOH (>70%) on these
loci was observed even among seven cases of stage I tumors. The incidence
of LOH on all 39 nonacrocentric chromosomal arms was not significantly
different between primary tumors and metastases. These results suggest that
inactivation of multiple tumor suppressor genes accumulates relatively
early during progression of SCLC and it may be responsible for clinically
and biologically aggressive phenotype of SCLC. RER was observed in 6/37
(16.2%) of SCLC, however, RER at multiple loci was observed only in two
cases. Therefore, it was indicated that genomic instability is uncommon,
but might play a role in the genesis of a small subset of SCLC.
相似文献