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91.
We examined the action of high (2×10–8M) and low (6×10–9M) concentrations of atrial natriuretic factor (ANF) on water and urea transport in the rat inner medullary collecting duct (IMCD) using the in vitro microperfusion technique. We measured the hydraulic conductivity (Lp ×10–6 cm/atm per second) and both lumen-to-bath (P u(lb)) and bath-to-lumen (P u(bl)) 14C-urea permeabilities (P u× 10–5 cm/s) in the absence and in the presence of vasopressin (VP). High concentrations of ANF were able to inhibit the maximum activity of (50 U/ml) VP-stimulated L p but physiological concentration of ANF inhibit only submaximum activity (10 U/ml) of VP-stimulated L p. The hydrosmotic effect of dibutyryl-cyclic 3,5 adenosine monophosphate (cAMP) (10–4M) was unchanged by high concentrations of ANF (2×10–8M). Also we found that high (10–4M) and low (10–6M) concentrations of exogenous cyclic 3,5-guanosine monophosphate (GMP) while unable to change the Lp in the absence of VP, decreased the maximum activity of VP-stimulated Lp significantly. We also found that ANF inhibits partially and in a reversible manner the VP-stimulated P u(lb) but not the VP-stimulated P u(bl). These results demonstrated that plasma concentrations of ANF observed during volume expansion (10–10M) are able to inhibit submaximum activity of VP-stimulated (10 U/ml) L p in the rat IMCD, this effect seems to occur before cAMP formation and it appears to be mediated by cGMP. ANF (6× 10–9M) also reduced the VP-stimulated urea outflux. Therefore, the increase in water excretion produced by ANF could be explained, at least in part, by the inhibition by ANF of vasopressin effects on water and urea transport in the IMCD.This study was presented in part at the VI Latin American Congress of Nephrology, Brazil, October 1985 and at the Xth International Congress of Nephrology, London, July 1987.  相似文献   
92.
The ionic conductive properties were studied of epithelia of collecting duct principal cells which had been grown in primary tissue culture from renal cortex/capsule explants. When pretreated with aldosterone (10–6 mol/l) and bathed on either surface with isotonic HCO 3 -free Ringer's solution, the transepithelial voltage,V te, varied between –21 and –72 mV (apical surface negative) while the transepithelial resistance,R te, ranged from 0.4 to 1.5 kcm2. By 10:1 step-changes in Na+ concentration the apical cell membrane was shown to have a high conductivity for sodium, inhibitable by amiloride, 10–6 mol/l. However, contrary to observations in natural collecting duct under control conditions, amiloride never reversed the polarity ofV te even at 10–4 mol/l. Both the apical and the basolateral cell membranes were conductive for potassium and both conductivities were inhibitable by Ba2+ (5 mmol/l). 10:1 reduction of apical Cl concentration strongly hyperpolarizedV te with a monophasic time course suggesting the presence of a paracellular shunt conductance for Cl. In addition there may be a small Cl conductance present in the apical cell membrane since apical application of the chloride channel blocker 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPAB) at 10–7 mol/l produced a minute but significant hyperpolarization. On the other hand, 10:1 reduction of basolateral Cl concentration caused a biphasic change inV te (initial depolarization, followed by repolarization) which indicates the presence of a large Cl conductance in the basolateral cell membrane. The latter was not inhibitable by 10–7 mol/l NPPAB. Higher concentrations of this and of an other Cl channel blocker produced non-specific effects. In conclusion, our studies of a pure principal cell epithelium confirm findings described for the intact cortical collecting duct and add new information concerning chloride conductivity and related blocking agents.Dedicated to Prof. Dr. H. Sitte, Homburg, FRG, upon his 60th birthday.  相似文献   
93.
肠系膜淋巴管结扎对MODS大鼠体液免疫功能的影响   总被引:1,自引:2,他引:1  
目的观察结扎肠系膜淋巴管对二次打击致大鼠多器官功能障碍综合征(MODS)体液免疫功能的影响,探讨淋巴途径在MODS发病学中的意义。方法雄性Wistar大鼠均分为结扎组、未结扎组、假手术组三组。前两组以失血-LPS二次打击方法,复制大鼠MODS模型。所有动物实验前后的血清均以免疫比浊法检测IgG、IgA、IgM、C3、C4含量,同时以放射免疫法检测血清TNFα作为反映炎症的指标。结果成功复制了MODS大鼠模型。二次打击后,未结扎组大鼠血清IgG、IgA、IgM、C3、C4及TNFα均显著高于结扎组、假手术组及实验前(P<0.01~0.05),而结扎组与假手术组无显著差异(P>0.05)。结论失血-LPS二次打击可使大鼠免疫球蛋白及补体增多,反映炎症反应剧烈及抗炎反应增强,而肠系膜淋巴管结扎可缓解炎症与抗炎反应,提高存活率,对机体有较好的保护作用。  相似文献   
94.
输精管精索部的应用解剖   总被引:1,自引:0,他引:1  
目的:为输精管结扎术、吻合术的临床应用提供形态学基础。方法:选用30具成人男性尸体对输精管精索部进行了解剖学观测。结果:输精管精索部位于精索后方,睾丸动脉位于中央,静脉位于最前方,生殖股神经生殖支位于输精管精索部外侧。输精管精索部长左侧7.6±2.9(50~11.3)cm;右侧7.3±3.2(5.2~11.0)cm。其内径左、右侧均为0.6±0.1(0.4~0.8)mm。经统计学处理(P>0.05)左右侧均无显著性差异。结论:在输精管结扎术、吻合术手术时应注意保护输精管外侧的生殖股神经生殖支、输精管精索部管径小、壁厚、吻合成功率高。因管径小、术后不宜安放支架,以免术后引起管腔阻塞。  相似文献   
95.
用31具成人正常肝标本人工镂空,赛璐璐灌注正常新鲜尸肝6具,观察和测量了1~3级肝管长度、周径和夹角以及与肝动脉、门静脉相互关系;正常尸肝15具和30例肝内胆管结石并狭窄的肝标本,光镜观察各级肝管壁组织结构和病理改变。讨论了胆管结石存在部位,高位肝管剖开取石和行胆肠吻合术的术式选择及注意事项。  相似文献   
96.
A case of papillary adenocarcinoma arising in Caroli's disease (CD) in a 25-yr-old woman is reported. The diagnosis of malignancy was made by ultrasound-guided, fine-needle aspiration biopsy (FNAB). As there were no metastasis, a liver transplant was performed and the diagnosis was histologically confirmed. Only 22 cases of malignant transformation of CD have been reported to date, all among middle-aged subjects (mean age: 52 yr) of both sexes. Most of these reported cases (83%) were found to be bile duct adenocarcinomas with occasional reports of hepatocellular and undifferentiated carcinomas. Our case is the youngest reported to date and the first to be diagnosed cytologically.  相似文献   
97.
Intraductal shock-wave lithotripsy in complicated common bile duct stones   总被引:1,自引:0,他引:1  
Summary Intracorporeal shockwave lithotripsy was performed in 36 patients with problematic common bile duct stones. All of the patients had undergone unsuccessful mechanical lithotripsy prior to this procedure. In 29 patients (80.6%), the stones were fragmented under cholangioscopic control and subsequently extracted with a Dormia basket. In seven patients, the procedure failed due to stone impaction or failure to intubate the common bile duct with a nasobiliary tube. No complications were observed. Cholangioscopically guided intracorporeal shockwave lithotripsy is a highly effective and safe procedure for the conservative treatment of complicated common bile duct stones.Abbreviations ESWL extracorporeal shock-wave lithotripsy - ISWL intracorporeal shock-wave lithotripsy Dedicated to Prof. Dr. med. Ludwig Demling on the occasion of his 70th birthday  相似文献   
98.
肝尾状叶脉管构筑的应用解剖   总被引:9,自引:1,他引:9  
应用55例成人肝剥离标本及45例胎儿、新生儿肝管道铸型,研究了肝尾状叶的鞘系及静脉回流。尾状叶有两个恒定的蒂、接受左、右侧鞘系的双重供应,以左侧为主;而尾状突主要由右后叶鞘系分布。15例肝铸型标本的尾状叶左、右侧动脉形成吻合弓。尾状叶动脉供应形式可分为三种,静脉可分为三型并直接汇入下腔静脉。由于血管吻合的存在,在病理状态下,尾状叶也应是沟通门一腔静脉的桥梁。  相似文献   
99.
Most models suggest that the cell of origin of papillary carcinoma is the mature thyroid follicular epithelial cell. In a recent study, p63 was detected in papillary carcinoma, Hashimoto's thyroiditis, and in squamoid aggregates and solid cell nests (SCNs), embryonic remnants found sporadically in the fully developed thyroid. In the present study, the relationship between solid cell nests and papillary carcinoma was investigated further. Four-micrometer sections from 88 routinely fixed and processed archival thyroidectomy specimens were pretreated with citric acid pH 6.0 for antigen retrieval, then incubated overnight with anti-p63 monoclonal antibody 4A4. Slides were stained with a streptavidin-biotin kit and diaminobenzidine as chromogen and were counterstained with hematoxylin. Squamoid aggregates or SCNs were noted in 21 specimens. Several morphologic variants of SCNs were found, all of which displayed p63 positivity. These included undifferentiated SCNs and those displaying commitment toward squamoid and ciliated glandular differentiation. Small, morphologically inconspicuous aggregates of p63-positive cells were commonly found in Hashimoto's thyroiditis. Commitment of p63-positive undifferentiated cells toward thyroid follicular epithelial differentiation was occasionally noted. One SCN variant, also associated with Hashimoto's thyroiditis, was a floretlike arrangement of p63-positive cells with fusiform nuclei. p63 staining was strong and uniform in some SCNs, but in other SCNs it was compartmentalized and homologous to stem cell-staining patterns in normal squamous or bronchial epithelia. Stem cell-like staining, associated with compartmentalized p63 staining or p63-positive undifferentiated cells, was noted in 7 of 27 papillary carcinomas. p63 immunostaining is a highly sensitive means of detecting SCNs. p63 expression patterns in SCNs and a subset of papillary carcinomas are closely homologous to stem cell-associated p63 staining patterns that have been described elsewhere in squamous and bronchial epithelia. We propose a stem-cell-associated model of papillary carcinoma oncogenesis that suggests that (1) p63-positive embryonal remnants rather than mature follicular cells are the cells of origin of a subset of papillary carcinomas; (2) these p63-positive cells are pluripotent and may stay undifferentiated or undergo benign squamoid or glandular maturation, may undergo thyroid follicular epithelial differentiation, may undergo oncogenic change leading to papillary carcinoma, or may trigger an immune reaction, resulting in lymphoid infiltration and Hashimoto's thyroiditis; and (3) Hashimoto's thyroiditis and papillary carcinoma may therefore be linked etiologically, because both disorders may be initiated by the same population of pluripotent p63-positive embryonal stem cell remnants.  相似文献   
100.
左肝管全程剖开手术,必须熟悉左肝管与邻近血管的局部解剖关系.为此我们用 ABS 丙酮溶液灌注塑型了6具新鲜成人尸肝脏,解剖40例(成人30,儿童10)肝脏标本,测量了左肝管长度和管径,左肝管与肝总管夹角。全程剖开左肝管与右肝管,并观察左肝管与右肝管、左肝动脉、门静脉左干和肝圆韧带的关系,提出了右肝管全程剖开手术方法和注意事项。  相似文献   
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