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871.
872.
Zinreich SJ; Wang H; Updike ML; Kumar AJ; Ahn HS; North RB; Rosenbaum AE 《Radiology》1985,157(2):387-390
The diagnostic usefulness, limitations, and adverse reactions associated with computed tomographic myelography using metrizamide were assessed for broad outpatient application. The initial approach was to examine inpatients (n = 38) with low-dose metrizamide (100 mgI/ml). This low dose was believed less likely to be associated with side effects. They were then treated as if they were outpatients, with the liberties this entailed. The consequences of needle puncture were minimized by using a 25-gauge disposable needle. Thirty-four (89%) patients remained free of side effects after the procedure. Subsequently, this technique was extended to 42 outpatients, 38 (90.5%) of whom remained asymptomatic. For comparison, 170 mgI/ml was used in another 25 outpatients, who evidenced more symptoms. The potential medical, economic, and therapeutic benefits of obviating hospitalization by safer outpatient CT myelography seem clear. 相似文献
873.
At diagnosis peripheral blood (PB) or bone marrow from patients with juvenile chronic myelogenous leukemia (JCML) have shown two reproducible abnormalities when studied in cell culture: impaired growth of normal hematopoietic progenitors and excessive proliferation of malignant monocyte-macrophage elements. We used these findings to assess quality of treatment response by serially studying PB specimens from four JCML patients (patients 5, 7, 8, and 9) in complete chemotherapy-induced remission. PB readily yielded high numbers of monocyte-macrophage colonies in CFU-C and CFU-GEMM assays when cultured in early remission, and the colonies were cytogenetically proven to have arisen from a malignant clone in patient 9. When studied later in remission, the abnormal cell proliferation persisted in three of the four patients, but in patient 8 PB colony growth resembled controls. Similarly, when PB from patient 8 was studied in liquid culture without using added growth factor, cell proliferation declined identical to controls, whereas PB from the other three patients showed exuberant growth of monocyte-macrophage elements. Patient 8 successfully completed therapy and has been in a long-term, disease-free remission. The other three had recurrent, ultimately fatal disease. The cell cultures have allowed detection of residual abnormal cells that circulate in PB of JCML patients in remission. Although patient numbers were small because of the rarity of JCML, the data suggested that persistence of leukemia cells in these patients had a bearing on clinical outcome. 相似文献
874.
Williams DE; Hangoc G; Cooper S; Boswell HS; Shadduck RK; Gillis S; Waheed A; Urdal D; Broxmeyer HE 《Blood》1987,70(2):401-403
Purified natural murine L cell (macrophage) colony-stimulating factor (nCSF-1) and purified recombinant murine interleukin-3 (rIL-3) were administered to normal or lactoferrin-pretreated mice 20 to 24 hours before sacrifice. rIL-3 and nCSF-1 administered separately increased the percentage of macrophage high-proliferative potential colony- forming cells (HPP-CFC) and low-proliferative potential colony-forming cells (LPP-CFC) in active cell cycle. Endotoxin was not detected in the samples of nCSF-1 or rIL-3 with the Limulus lysate test, and the in vitro and in vivo hematopoietic stimulatory effects of both molecules were abolished or markedly reduced by 30 minutes' treatment at 100 degrees C, which demonstrates that the effects noted in vivo were not due to endotoxin. Combinations of low concentrations of rIL-3 and nCSF- 1, which by themselves were inactive, increased the percentage of HPP- CFC and LPP-CFC in active cell cycle in a synergistic fashion. No significant change in the number of HPP-CFC or LPP-CFC per femur or femoral nucleated cellularity was observed. Thus, rIL-3 and nCSF-1 can synergize to effect the proliferation of the same cell populations in vivo. 相似文献
875.
Physiological insights gained in the 1980s into mechanisms of disease progression in experimental chronic nephropathies established the basis for therapeutic interventions to retard the progression of chronic renal disease in humans. In the 1990s, several large-scale clinical trials have confirmed the renoprotective effects of angiotensin-converting enzyme inhibitors in diabetic and nondiabetic nephropathies. Other studies have afforded strong support for the efficacy of dietary protein restriction in certain settings and underscored the importance of blood pressure control in proteinuric individuals. These interventions form the core of current strategies designed to preserve kidney function in patients with chronic renal disease. 相似文献
876.
877.
中药槐花米的化学成分研究[Ⅰ]槐花米甲素(1) 总被引:2,自引:0,他引:2
Hwai-Hua-Me has long been used as insecticide,dye-stuff,nutriment,heamosta- tic agent as well as remedies for haemorrhoids and brain hyperemia (apoplexy). Hitherto six substances have been isolated by the author from a sample ob- tainable in Shanghai. The presant paper deals with the study of Sorphorine-A,a yellowish crystal- line subtance.The yield is about 14%.The sample was first extracted with dilute alcohol,then washed with ether,acetone and petroleum ether,and the Product was recrystallized from alcohol and hot water,and then reated with methyl alcohol and ether mixture in order to remove Sorphorn-B,Sorphorin-C & etc.The substance thus obtained gives the following: m.p.180-182°(bulbing),185-188°(Changing forom),199-203°(Sintering with plastic appearance) and decomposing at 245-250°). [a]D24=+12°(0.5% C2H5OH);+5°(% CH3OH). Mol.formula:C29H36O17. Crystallization of water:7.16;7.33%;CH29H-(36)O17·3H2O. Crystallizion of methyl alcohol:4.86%,C29H36O17·CH3OH. Crystallization of ethyl alcohol:6.57%,C29H36O17·C2H5OH. Solubility:cold water(1:60,000);boiling water (1:167). cold methyl alcohol(1:1,080);boiling methyl alcohol(111:100). cold ethyl alcohol(1:600);boiling ethyl alcohol(3:5). cold acetone(1:600);boiling acetone(1:350). Pyridine(1:12). cold dioxan(1:12);boiling dioxan(1:15). cold ethyl acetate(trace);boiling ethyl acetate(small). cold amyl alcohol(slightly);hot amyl alcohol(slightly). Reactions:1.Tollen's reagent:black ppt. 2.Fehling's solution:no reaction. 3.HCl+Mg+C2H5OH:reddish purple coloration. 4.HAC+Mg+C2H5OH:greenish fluorescence. 5.Hydrolysis(1:100 HCl): a.yellowish brown crystals(yield 59%),306-308°(blackens),310-311° (melts),C17H13(14)O9(10). b.acetone Insoluble osazone:m.p.215-217°(D). c.acetone soluble osazone:m.p.188-189. 6.FeCl3 solution:dark green solution. 7.Lead acetate solution:Lemon-yellow ppt. 8.Basic lead acetate solution:yellowish Orange ppt. 9.Hydrolyzed product:yellowish brown crystal. a.FeCl3 solotion:bark green solution. b.Lead acetate:yellowish orange ppt. c.Tollen's reagent:black ppt. d.Fehling's solution:no reaction. e.Acetate,C27(28) H23(24)O14:m.p.198-203°,CH3CO%=44.4%;hydro- lyzed with KOH,give greenish yellow crystals,yield about 98% with m.p.310-312°(D). f.Methyated:(1)m.p.300-302° greenish yellow. (2)m.p.151-152° slight yellowish white. The spectrophotometric determination: As show in Fig.Vl (1) Hwai-hua-menine-A exhibits absorption at E1cm1% 258 mμ =353;E1cm1% 364 mμ=277.8(95% ethyl alcohol+1% 0.2N HAC),(Conc.1.551 mg/100CC.)(Beckman DU). (2) aglucone of Hwai-Hua-Menine-A exhibits absorpotion at: E1cm1% 258 mμ=660;E1c%1% 375 mμ=550. The paper chromatography determination: Solvent:n-butanol:acetic acid:water=4:1:5 for 10 hours. Rf.=0.68 (0.71-0.72) Aglucone:Rf=0.75.(0.73) Acetic acid:water(6:4 V/V), Rf.=0.71,0.72;Aglucone:Rf=0 The active Oh-groug of aglucone(Tschugajiff Zerrmettinoff's method 26.8%.) The mixed m.p.of rutin(obtained from leaf and stem of Fagoyprum esculentuni, Moench 蕎麦茎叶) and Hwai-Hua-Menine-A:154°(contract),180-190°(syrup), 240-250°(D). It may be concluded from the above results,that the compound is neither rutin, nor its homologues. 相似文献
878.
The administration of testosterone via Silastic capsules has been shown previously to maintain advanced spermatid number quantitatively in intact rats in which LH but not FSH was suppressed, but not in hypophysectomized rats, indicating that pituitary factors in addition to LH are required for the quantitative maintenance of spermatogenesis in the rat. The objective of the present study was to examine whether testosterone is capable of maintaining quantitatively normal spermatogenesis in rats in which both LH and FSH are suppressed. Intact adult male rats were actively immunized against GnRH by intradermal injection of GnRH conjugated to human serum globulin; control rats received intradermal injections of saline and adjuvant. Four weeks after the primary immunization, GnRH-immunized rats received the first booster injection and, at the same time, received testosterone-filled polydimethylsiloxane (PDS) implants of 4, 8, 12, or 24 cm or empty implants. Booster injections were repeated every 2 weeks for 8 weeks. At that time, rats were killed, and serum levels of LH, FSH, and testosterone, testicular advanced spermatid number, and seminiferous tubule fluid testosterone concentrations were determined. Four weeks after the initial administration of GnRH immunogen, i.e. before the first booster injection, serum levels of testosterone, LH, and FSH and the number of advanced spermatids per testis were not different from those in controls. Eight weeks after the first booster injection, serum LH and FSH and advanced spermatids were undetectable in all GnRH-immunized rats. The administration of testosterone-filled PDS implants of 4 and 8 cm to GnRH-immunized rats for 8 weeks resulted in the maintenance of 105 +/- 6 and 161 +/- 5 x 10(6) advanced spermatid/testis, respectively, significantly less than the control value (237 +/- 19 x 10(6)). In GnRH-immunized rats that received testosterone-filled PDS implants of 12 or 24 cm, the advanced spermatid numbers per testis (228 +/- 4 and 229 +/- 8 x 10(6), respectively) were not significantly different from those in controls. These results indicate that testosterone is capable of maintaining spermatogenesis quantitatively in the adult rats testis, in the absence of both radioimmunoassayable LH and FSH. 相似文献
879.
本文选择了6种香豆酮化合物(其中5种为呋喃香豆素),对不含粘合剂氧化鋁薄层层离法的一些条件进行了研究。結果采用細度小于160号篩孔,活性2—3級的酸性氧化鋁为吸附剂;石油醚:氯仿(1:1)、石油醚:二氧六环(10:2)、石油醚:乙醇(1:1)等溶剂为推进剂。在推进前不必进行蒸气飽和。此法可以应用于一些香豆酮化合物的鉴定和小量分离,并应用于前胡和藁本研究工作而获得一定結果。 相似文献